linux/arch/mips/kernel/traps.c

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/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1994 - 1999, 2000, 01, 06 Ralf Baechle
* Copyright (C) 1995, 1996 Paul M. Antoine
* Copyright (C) 1998 Ulf Carlsson
* Copyright (C) 1999 Silicon Graphics, Inc.
* Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
* Copyright (C) 2000, 01 MIPS Technologies, Inc.
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
* Copyright (C) 2002, 2003, 2004, 2005, 2007 Maciej W. Rozycki
*/
#include <linux/bug.h>
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
#include <linux/compiler.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
#include <linux/kallsyms.h>
#include <linux/bootmem.h>
#include <linux/interrupt.h>
#include <linux/ptrace.h>
#include <linux/kgdb.h>
#include <linux/kdebug.h>
#include <linux/kprobes.h>
#include <linux/notifier.h>
#include <linux/kdb.h>
#include <linux/irq.h>
#include <linux/perf_event.h>
#include <asm/bootinfo.h>
#include <asm/branch.h>
#include <asm/break.h>
#include <asm/cop2.h>
#include <asm/cpu.h>
#include <asm/dsp.h>
#include <asm/fpu.h>
#include <asm/fpu_emulator.h>
#include <asm/mipsregs.h>
#include <asm/mipsmtregs.h>
#include <asm/module.h>
#include <asm/pgtable.h>
#include <asm/ptrace.h>
#include <asm/sections.h>
#include <asm/tlbdebug.h>
#include <asm/traps.h>
#include <asm/uaccess.h>
#include <asm/watch.h>
#include <asm/mmu_context.h>
#include <asm/types.h>
#include <asm/stacktrace.h>
#include <asm/uasm.h>
extern void check_wait(void);
extern asmlinkage void r4k_wait(void);
extern asmlinkage void rollback_handle_int(void);
extern asmlinkage void handle_int(void);
extern asmlinkage void handle_tlbm(void);
extern asmlinkage void handle_tlbl(void);
extern asmlinkage void handle_tlbs(void);
extern asmlinkage void handle_adel(void);
extern asmlinkage void handle_ades(void);
extern asmlinkage void handle_ibe(void);
extern asmlinkage void handle_dbe(void);
extern asmlinkage void handle_sys(void);
extern asmlinkage void handle_bp(void);
extern asmlinkage void handle_ri(void);
extern asmlinkage void handle_ri_rdhwr_vivt(void);
extern asmlinkage void handle_ri_rdhwr(void);
extern asmlinkage void handle_cpu(void);
extern asmlinkage void handle_ov(void);
extern asmlinkage void handle_tr(void);
extern asmlinkage void handle_fpe(void);
extern asmlinkage void handle_mdmx(void);
extern asmlinkage void handle_watch(void);
extern asmlinkage void handle_mt(void);
extern asmlinkage void handle_dsp(void);
extern asmlinkage void handle_mcheck(void);
extern asmlinkage void handle_reserved(void);
extern int fpu_emulator_cop1Handler(struct pt_regs *xcp,
struct mips_fpu_struct *ctx, int has_fpu,
void *__user *fault_addr);
void (*board_be_init)(void);
int (*board_be_handler)(struct pt_regs *regs, int is_fixup);
void (*board_nmi_handler_setup)(void);
void (*board_ejtag_handler_setup)(void);
void (*board_bind_eic_interrupt)(int irq, int regset);
void (*board_ebase_setup)(void);
void __cpuinitdata(*board_cache_error_setup)(void);
static void show_raw_backtrace(unsigned long reg29)
{
unsigned long *sp = (unsigned long *)(reg29 & ~3);
unsigned long addr;
printk("Call Trace:");
#ifdef CONFIG_KALLSYMS
printk("\n");
#endif
while (!kstack_end(sp)) {
unsigned long __user *p =
(unsigned long __user *)(unsigned long)sp++;
if (__get_user(addr, p)) {
printk(" (Bad stack address)");
break;
}
if (__kernel_text_address(addr))
print_ip_sym(addr);
}
printk("\n");
}
#ifdef CONFIG_KALLSYMS
int raw_show_trace;
static int __init set_raw_show_trace(char *str)
{
raw_show_trace = 1;
return 1;
}
__setup("raw_show_trace", set_raw_show_trace);
#endif
static void show_backtrace(struct task_struct *task, const struct pt_regs *regs)
{
unsigned long sp = regs->regs[29];
unsigned long ra = regs->regs[31];
unsigned long pc = regs->cp0_epc;
if (raw_show_trace || !__kernel_text_address(pc)) {
show_raw_backtrace(sp);
return;
}
printk("Call Trace:\n");
do {
print_ip_sym(pc);
pc = unwind_stack(task, &sp, pc, &ra);
} while (pc);
printk("\n");
}
/*
* This routine abuses get_user()/put_user() to reference pointers
* with at least a bit of error checking ...
*/
static void show_stacktrace(struct task_struct *task,
const struct pt_regs *regs)
{
const int field = 2 * sizeof(unsigned long);
long stackdata;
int i;
unsigned long __user *sp = (unsigned long __user *)regs->regs[29];
printk("Stack :");
i = 0;
while ((unsigned long) sp & (PAGE_SIZE - 1)) {
if (i && ((i % (64 / field)) == 0))
printk("\n ");
if (i > 39) {
printk(" ...");
break;
}
if (__get_user(stackdata, sp++)) {
printk(" (Bad stack address)");
break;
}
printk(" %0*lx", field, stackdata);
i++;
}
printk("\n");
show_backtrace(task, regs);
}
void show_stack(struct task_struct *task, unsigned long *sp)
{
struct pt_regs regs;
if (sp) {
regs.regs[29] = (unsigned long)sp;
regs.regs[31] = 0;
regs.cp0_epc = 0;
} else {
if (task && task != current) {
regs.regs[29] = task->thread.reg29;
regs.regs[31] = 0;
regs.cp0_epc = task->thread.reg31;
#ifdef CONFIG_KGDB_KDB
} else if (atomic_read(&kgdb_active) != -1 &&
kdb_current_regs) {
memcpy(&regs, kdb_current_regs, sizeof(regs));
#endif /* CONFIG_KGDB_KDB */
} else {
prepare_frametrace(&regs);
}
}
show_stacktrace(task, &regs);
}
/*
* The architecture-independent dump_stack generator
*/
void dump_stack(void)
{
struct pt_regs regs;
prepare_frametrace(&regs);
show_backtrace(current, &regs);
}
EXPORT_SYMBOL(dump_stack);
static void show_code(unsigned int __user *pc)
{
long i;
unsigned short __user *pc16 = NULL;
printk("\nCode:");
if ((unsigned long)pc & 1)
pc16 = (unsigned short __user *)((unsigned long)pc & ~1);
for(i = -3 ; i < 6 ; i++) {
unsigned int insn;
if (pc16 ? __get_user(insn, pc16 + i) : __get_user(insn, pc + i)) {
printk(" (Bad address in epc)\n");
break;
}
printk("%c%0*x%c", (i?' ':'<'), pc16 ? 4 : 8, insn, (i?' ':'>'));
}
}
static void __show_regs(const struct pt_regs *regs)
{
const int field = 2 * sizeof(unsigned long);
unsigned int cause = regs->cp0_cause;
int i;
printk("Cpu %d\n", smp_processor_id());
/*
* Saved main processor registers
*/
for (i = 0; i < 32; ) {
if ((i % 4) == 0)
printk("$%2d :", i);
if (i == 0)
printk(" %0*lx", field, 0UL);
else if (i == 26 || i == 27)
printk(" %*s", field, "");
else
printk(" %0*lx", field, regs->regs[i]);
i++;
if ((i % 4) == 0)
printk("\n");
}
#ifdef CONFIG_CPU_HAS_SMARTMIPS
printk("Acx : %0*lx\n", field, regs->acx);
#endif
printk("Hi : %0*lx\n", field, regs->hi);
printk("Lo : %0*lx\n", field, regs->lo);
/*
* Saved cp0 registers
*/
printk("epc : %0*lx %pS\n", field, regs->cp0_epc,
(void *) regs->cp0_epc);
printk(" %s\n", print_tainted());
printk("ra : %0*lx %pS\n", field, regs->regs[31],
(void *) regs->regs[31]);
printk("Status: %08x ", (uint32_t) regs->cp0_status);
if (current_cpu_data.isa_level == MIPS_CPU_ISA_I) {
if (regs->cp0_status & ST0_KUO)
printk("KUo ");
if (regs->cp0_status & ST0_IEO)
printk("IEo ");
if (regs->cp0_status & ST0_KUP)
printk("KUp ");
if (regs->cp0_status & ST0_IEP)
printk("IEp ");
if (regs->cp0_status & ST0_KUC)
printk("KUc ");
if (regs->cp0_status & ST0_IEC)
printk("IEc ");
} else {
if (regs->cp0_status & ST0_KX)
printk("KX ");
if (regs->cp0_status & ST0_SX)
printk("SX ");
if (regs->cp0_status & ST0_UX)
printk("UX ");
switch (regs->cp0_status & ST0_KSU) {
case KSU_USER:
printk("USER ");
break;
case KSU_SUPERVISOR:
printk("SUPERVISOR ");
break;
case KSU_KERNEL:
printk("KERNEL ");
break;
default:
printk("BAD_MODE ");
break;
}
if (regs->cp0_status & ST0_ERL)
printk("ERL ");
if (regs->cp0_status & ST0_EXL)
printk("EXL ");
if (regs->cp0_status & ST0_IE)
printk("IE ");
}
printk("\n");
printk("Cause : %08x\n", cause);
cause = (cause & CAUSEF_EXCCODE) >> CAUSEB_EXCCODE;
if (1 <= cause && cause <= 5)
printk("BadVA : %0*lx\n", field, regs->cp0_badvaddr);
printk("PrId : %08x (%s)\n", read_c0_prid(),
cpu_name_string());
}
/*
* FIXME: really the generic show_regs should take a const pointer argument.
*/
void show_regs(struct pt_regs *regs)
{
__show_regs((struct pt_regs *)regs);
}
void show_registers(struct pt_regs *regs)
{
const int field = 2 * sizeof(unsigned long);
__show_regs(regs);
print_modules();
printk("Process %s (pid: %d, threadinfo=%p, task=%p, tls=%0*lx)\n",
current->comm, current->pid, current_thread_info(), current,
field, current_thread_info()->tp_value);
if (cpu_has_userlocal) {
unsigned long tls;
tls = read_c0_userlocal();
if (tls != current_thread_info()->tp_value)
printk("*HwTLS: %0*lx\n", field, tls);
}
show_stacktrace(current, regs);
show_code((unsigned int __user *) regs->cp0_epc);
printk("\n");
}
static int regs_to_trapnr(struct pt_regs *regs)
{
return (regs->cp0_cause >> 2) & 0x1f;
}
static DEFINE_RAW_SPINLOCK(die_lock);
void __noreturn die(const char *str, struct pt_regs *regs)
{
static int die_counter;
int sig = SIGSEGV;
#ifdef CONFIG_MIPS_MT_SMTC
unsigned long dvpret;
#endif /* CONFIG_MIPS_MT_SMTC */
oops_enter();
if (notify_die(DIE_OOPS, str, regs, 0, regs_to_trapnr(regs), SIGSEGV) == NOTIFY_STOP)
sig = 0;
console_verbose();
raw_spin_lock_irq(&die_lock);
#ifdef CONFIG_MIPS_MT_SMTC
dvpret = dvpe();
#endif /* CONFIG_MIPS_MT_SMTC */
bust_spinlocks(1);
#ifdef CONFIG_MIPS_MT_SMTC
mips_mt_regdump(dvpret);
#endif /* CONFIG_MIPS_MT_SMTC */
printk("%s[#%d]:\n", str, ++die_counter);
show_registers(regs);
add_taint(TAINT_DIE);
raw_spin_unlock_irq(&die_lock);
oops_exit();
if (in_interrupt())
panic("Fatal exception in interrupt");
if (panic_on_oops) {
printk(KERN_EMERG "Fatal exception: panic in 5 seconds");
ssleep(5);
panic("Fatal exception");
}
do_exit(sig);
}
extern struct exception_table_entry __start___dbe_table[];
extern struct exception_table_entry __stop___dbe_table[];
__asm__(
" .section __dbe_table, \"a\"\n"
" .previous \n");
/* Given an address, look for it in the exception tables. */
static const struct exception_table_entry *search_dbe_tables(unsigned long addr)
{
const struct exception_table_entry *e;
e = search_extable(__start___dbe_table, __stop___dbe_table - 1, addr);
if (!e)
e = search_module_dbetables(addr);
return e;
}
asmlinkage void do_be(struct pt_regs *regs)
{
const int field = 2 * sizeof(unsigned long);
const struct exception_table_entry *fixup = NULL;
int data = regs->cp0_cause & 4;
int action = MIPS_BE_FATAL;
/* XXX For now. Fixme, this searches the wrong table ... */
if (data && !user_mode(regs))
fixup = search_dbe_tables(exception_epc(regs));
if (fixup)
action = MIPS_BE_FIXUP;
if (board_be_handler)
action = board_be_handler(regs, fixup != NULL);
switch (action) {
case MIPS_BE_DISCARD:
return;
case MIPS_BE_FIXUP:
if (fixup) {
regs->cp0_epc = fixup->nextinsn;
return;
}
break;
default:
break;
}
/*
* Assume it would be too dangerous to continue ...
*/
printk(KERN_ALERT "%s bus error, epc == %0*lx, ra == %0*lx\n",
data ? "Data" : "Instruction",
field, regs->cp0_epc, field, regs->regs[31]);
if (notify_die(DIE_OOPS, "bus error", regs, 0, regs_to_trapnr(regs), SIGBUS)
== NOTIFY_STOP)
return;
die_if_kernel("Oops", regs);
force_sig(SIGBUS, current);
}
/*
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
* ll/sc, rdhwr, sync emulation
*/
#define OPCODE 0xfc000000
#define BASE 0x03e00000
#define RT 0x001f0000
#define OFFSET 0x0000ffff
#define LL 0xc0000000
#define SC 0xe0000000
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
#define SPEC0 0x00000000
#define SPEC3 0x7c000000
#define RD 0x0000f800
#define FUNC 0x0000003f
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
#define SYNC 0x0000000f
#define RDHWR 0x0000003b
/*
* The ll_bit is cleared by r*_switch.S
*/
unsigned int ll_bit;
struct task_struct *ll_task;
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
static inline int simulate_ll(struct pt_regs *regs, unsigned int opcode)
{
unsigned long value, __user *vaddr;
long offset;
/*
* analyse the ll instruction that just caused a ri exception
* and put the referenced address to addr.
*/
/* sign extend offset */
offset = opcode & OFFSET;
offset <<= 16;
offset >>= 16;
vaddr = (unsigned long __user *)
((unsigned long)(regs->regs[(opcode & BASE) >> 21]) + offset);
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
if ((unsigned long)vaddr & 3)
return SIGBUS;
if (get_user(value, vaddr))
return SIGSEGV;
preempt_disable();
if (ll_task == NULL || ll_task == current) {
ll_bit = 1;
} else {
ll_bit = 0;
}
ll_task = current;
preempt_enable();
regs->regs[(opcode & RT) >> 16] = value;
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
return 0;
}
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
static inline int simulate_sc(struct pt_regs *regs, unsigned int opcode)
{
unsigned long __user *vaddr;
unsigned long reg;
long offset;
/*
* analyse the sc instruction that just caused a ri exception
* and put the referenced address to addr.
*/
/* sign extend offset */
offset = opcode & OFFSET;
offset <<= 16;
offset >>= 16;
vaddr = (unsigned long __user *)
((unsigned long)(regs->regs[(opcode & BASE) >> 21]) + offset);
reg = (opcode & RT) >> 16;
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
if ((unsigned long)vaddr & 3)
return SIGBUS;
preempt_disable();
if (ll_bit == 0 || ll_task != current) {
regs->regs[reg] = 0;
preempt_enable();
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
return 0;
}
preempt_enable();
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
if (put_user(regs->regs[reg], vaddr))
return SIGSEGV;
regs->regs[reg] = 1;
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
return 0;
}
/*
* ll uses the opcode of lwc0 and sc uses the opcode of swc0. That is both
* opcodes are supposed to result in coprocessor unusable exceptions if
* executed on ll/sc-less processors. That's the theory. In practice a
* few processors such as NEC's VR4100 throw reserved instruction exceptions
* instead, so we're doing the emulation thing in both exception handlers.
*/
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
static int simulate_llsc(struct pt_regs *regs, unsigned int opcode)
{
if ((opcode & OPCODE) == LL) {
perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
1, regs, 0);
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
return simulate_ll(regs, opcode);
}
if ((opcode & OPCODE) == SC) {
perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
1, regs, 0);
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
return simulate_sc(regs, opcode);
}
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
return -1; /* Must be something else ... */
}
/*
* Simulate trapping 'rdhwr' instructions to provide user accessible
* registers not implemented in hardware.
*/
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
static int simulate_rdhwr(struct pt_regs *regs, unsigned int opcode)
{
struct thread_info *ti = task_thread_info(current);
if ((opcode & OPCODE) == SPEC3 && (opcode & FUNC) == RDHWR) {
int rd = (opcode & RD) >> 11;
int rt = (opcode & RT) >> 16;
perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
1, regs, 0);
switch (rd) {
case 0: /* CPU number */
regs->regs[rt] = smp_processor_id();
return 0;
case 1: /* SYNCI length */
regs->regs[rt] = min(current_cpu_data.dcache.linesz,
current_cpu_data.icache.linesz);
return 0;
case 2: /* Read count register */
regs->regs[rt] = read_c0_count();
return 0;
case 3: /* Count register resolution */
switch (current_cpu_data.cputype) {
case CPU_20KC:
case CPU_25KF:
regs->regs[rt] = 1;
break;
default:
regs->regs[rt] = 2;
}
return 0;
case 29:
regs->regs[rt] = ti->tp_value;
return 0;
default:
return -1;
}
}
/* Not ours. */
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
return -1;
}
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
static int simulate_sync(struct pt_regs *regs, unsigned int opcode)
{
if ((opcode & OPCODE) == SPEC0 && (opcode & FUNC) == SYNC) {
perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
1, regs, 0);
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
return 0;
}
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
return -1; /* Must be something else ... */
}
asmlinkage void do_ov(struct pt_regs *regs)
{
siginfo_t info;
die_if_kernel("Integer overflow", regs);
info.si_code = FPE_INTOVF;
info.si_signo = SIGFPE;
info.si_errno = 0;
info.si_addr = (void __user *) regs->cp0_epc;
force_sig_info(SIGFPE, &info, current);
}
static int process_fpemu_return(int sig, void __user *fault_addr)
{
if (sig == SIGSEGV || sig == SIGBUS) {
struct siginfo si = {0};
si.si_addr = fault_addr;
si.si_signo = sig;
if (sig == SIGSEGV) {
if (find_vma(current->mm, (unsigned long)fault_addr))
si.si_code = SEGV_ACCERR;
else
si.si_code = SEGV_MAPERR;
} else {
si.si_code = BUS_ADRERR;
}
force_sig_info(sig, &si, current);
return 1;
} else if (sig) {
force_sig(sig, current);
return 1;
} else {
return 0;
}
}
/*
* XXX Delayed fp exceptions when doing a lazy ctx switch XXX
*/
asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31)
{
siginfo_t info = {0};
if (notify_die(DIE_FP, "FP exception", regs, 0, regs_to_trapnr(regs), SIGFPE)
== NOTIFY_STOP)
return;
die_if_kernel("FP exception in kernel code", regs);
if (fcr31 & FPU_CSR_UNI_X) {
int sig;
void __user *fault_addr = NULL;
/*
* Unimplemented operation exception. If we've got the full
* software emulator on-board, let's use it...
*
* Force FPU to dump state into task/thread context. We're
* moving a lot of data here for what is probably a single
* instruction, but the alternative is to pre-decode the FP
* register operands before invoking the emulator, which seems
* a bit extreme for what should be an infrequent event.
*/
/* Ensure 'resume' not overwrite saved fp context again. */
lose_fpu(1);
/* Run the emulator */
sig = fpu_emulator_cop1Handler(regs, &current->thread.fpu, 1,
&fault_addr);
/*
* We can't allow the emulated instruction to leave any of
* the cause bit set in $fcr31.
*/
current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X;
/* Restore the hardware register state */
own_fpu(1); /* Using the FPU again. */
/* If something went wrong, signal */
process_fpemu_return(sig, fault_addr);
return;
} else if (fcr31 & FPU_CSR_INV_X)
info.si_code = FPE_FLTINV;
else if (fcr31 & FPU_CSR_DIV_X)
info.si_code = FPE_FLTDIV;
else if (fcr31 & FPU_CSR_OVF_X)
info.si_code = FPE_FLTOVF;
else if (fcr31 & FPU_CSR_UDF_X)
info.si_code = FPE_FLTUND;
else if (fcr31 & FPU_CSR_INE_X)
info.si_code = FPE_FLTRES;
else
info.si_code = __SI_FAULT;
info.si_signo = SIGFPE;
info.si_errno = 0;
info.si_addr = (void __user *) regs->cp0_epc;
force_sig_info(SIGFPE, &info, current);
}
static void do_trap_or_bp(struct pt_regs *regs, unsigned int code,
const char *str)
{
siginfo_t info;
char b[40];
#ifdef CONFIG_KGDB_LOW_LEVEL_TRAP
if (kgdb_ll_trap(DIE_TRAP, str, regs, code, regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP)
return;
#endif /* CONFIG_KGDB_LOW_LEVEL_TRAP */
if (notify_die(DIE_TRAP, str, regs, code, regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP)
return;
/*
* A short test says that IRIX 5.3 sends SIGTRAP for all trap
* insns, even for trap and break codes that indicate arithmetic
* failures. Weird ...
* But should we continue the brokenness??? --macro
*/
switch (code) {
case BRK_OVERFLOW:
case BRK_DIVZERO:
scnprintf(b, sizeof(b), "%s instruction in kernel code", str);
die_if_kernel(b, regs);
if (code == BRK_DIVZERO)
info.si_code = FPE_INTDIV;
else
info.si_code = FPE_INTOVF;
info.si_signo = SIGFPE;
info.si_errno = 0;
info.si_addr = (void __user *) regs->cp0_epc;
force_sig_info(SIGFPE, &info, current);
break;
case BRK_BUG:
die_if_kernel("Kernel bug detected", regs);
force_sig(SIGTRAP, current);
break;
case BRK_MEMU:
/*
* Address errors may be deliberately induced by the FPU
* emulator to retake control of the CPU after executing the
* instruction in the delay slot of an emulated branch.
*
* Terminate if exception was recognized as a delay slot return
* otherwise handle as normal.
*/
if (do_dsemulret(regs))
return;
die_if_kernel("Math emu break/trap", regs);
force_sig(SIGTRAP, current);
break;
default:
scnprintf(b, sizeof(b), "%s instruction in kernel code", str);
die_if_kernel(b, regs);
force_sig(SIGTRAP, current);
}
}
asmlinkage void do_bp(struct pt_regs *regs)
{
unsigned int opcode, bcode;
if (__get_user(opcode, (unsigned int __user *) exception_epc(regs)))
goto out_sigsegv;
/*
* There is the ancient bug in the MIPS assemblers that the break
* code starts left to bit 16 instead to bit 6 in the opcode.
* Gas is bug-compatible, but not always, grrr...
* We handle both cases with a simple heuristics. --macro
*/
bcode = ((opcode >> 6) & ((1 << 20) - 1));
if (bcode >= (1 << 10))
bcode >>= 10;
/*
* notify the kprobe handlers, if instruction is likely to
* pertain to them.
*/
switch (bcode) {
case BRK_KPROBE_BP:
if (notify_die(DIE_BREAK, "debug", regs, bcode, regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP)
return;
else
break;
case BRK_KPROBE_SSTEPBP:
if (notify_die(DIE_SSTEPBP, "single_step", regs, bcode, regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP)
return;
else
break;
default:
break;
}
do_trap_or_bp(regs, bcode, "Break");
return;
out_sigsegv:
force_sig(SIGSEGV, current);
}
asmlinkage void do_tr(struct pt_regs *regs)
{
unsigned int opcode, tcode = 0;
if (__get_user(opcode, (unsigned int __user *) exception_epc(regs)))
goto out_sigsegv;
/* Immediate versions don't provide a code. */
if (!(opcode & OPCODE))
tcode = ((opcode >> 6) & ((1 << 10) - 1));
do_trap_or_bp(regs, tcode, "Trap");
return;
out_sigsegv:
force_sig(SIGSEGV, current);
}
asmlinkage void do_ri(struct pt_regs *regs)
{
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
unsigned int __user *epc = (unsigned int __user *)exception_epc(regs);
unsigned long old_epc = regs->cp0_epc;
unsigned int opcode = 0;
int status = -1;
if (notify_die(DIE_RI, "RI Fault", regs, 0, regs_to_trapnr(regs), SIGILL)
== NOTIFY_STOP)
return;
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
die_if_kernel("Reserved instruction in kernel code", regs);
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
if (unlikely(compute_return_epc(regs) < 0))
return;
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
if (unlikely(get_user(opcode, epc) < 0))
status = SIGSEGV;
if (!cpu_has_llsc && status < 0)
status = simulate_llsc(regs, opcode);
if (status < 0)
status = simulate_rdhwr(regs, opcode);
if (status < 0)
status = simulate_sync(regs, opcode);
if (status < 0)
status = SIGILL;
if (unlikely(status > 0)) {
regs->cp0_epc = old_epc; /* Undo skip-over. */
force_sig(status, current);
}
}
/*
* MIPS MT processors may have fewer FPU contexts than CPU threads. If we've
* emulated more than some threshold number of instructions, force migration to
* a "CPU" that has FP support.
*/
static void mt_ase_fp_affinity(void)
{
#ifdef CONFIG_MIPS_MT_FPAFF
if (mt_fpemul_threshold > 0 &&
((current->thread.emulated_fp++ > mt_fpemul_threshold))) {
/*
* If there's no FPU present, or if the application has already
* restricted the allowed set to exclude any CPUs with FPUs,
* we'll skip the procedure.
*/
if (cpus_intersects(current->cpus_allowed, mt_fpu_cpumask)) {
cpumask_t tmask;
current->thread.user_cpus_allowed
= current->cpus_allowed;
cpus_and(tmask, current->cpus_allowed,
mt_fpu_cpumask);
set_cpus_allowed_ptr(current, &tmask);
set_thread_flag(TIF_FPUBOUND);
}
}
#endif /* CONFIG_MIPS_MT_FPAFF */
}
/*
* No lock; only written during early bootup by CPU 0.
*/
static RAW_NOTIFIER_HEAD(cu2_chain);
int __ref register_cu2_notifier(struct notifier_block *nb)
{
return raw_notifier_chain_register(&cu2_chain, nb);
}
int cu2_notifier_call_chain(unsigned long val, void *v)
{
return raw_notifier_call_chain(&cu2_chain, val, v);
}
static int default_cu2_call(struct notifier_block *nfb, unsigned long action,
void *data)
{
struct pt_regs *regs = data;
switch (action) {
default:
die_if_kernel("Unhandled kernel unaligned access or invalid "
"instruction", regs);
/* Fall through */
case CU2_EXCEPTION:
force_sig(SIGILL, current);
}
return NOTIFY_OK;
}
asmlinkage void do_cpu(struct pt_regs *regs)
{
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
unsigned int __user *epc;
unsigned long old_epc;
unsigned int opcode;
unsigned int cpid;
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
int status;
unsigned long __maybe_unused flags;
die_if_kernel("do_cpu invoked from kernel context!", regs);
cpid = (regs->cp0_cause >> CAUSEB_CE) & 3;
switch (cpid) {
case 0:
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
epc = (unsigned int __user *)exception_epc(regs);
old_epc = regs->cp0_epc;
opcode = 0;
status = -1;
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
if (unlikely(compute_return_epc(regs) < 0))
return;
[MIPS] SYNC emulation for MIPS I processors Userland, including the C library and the dynamic linker, is keen to use the SYNC instruction, even for "generic" MIPS I binaries these days. Which makes it less than useful on MIPS I processors. This change adds the emulation, but as our do_ri() infrastructure was not really prepared to take yet another instruction, I have rewritten it and its callees slightly as follows. Now there is only a single place a possible signal is thrown from. The place is at the end of do_ri(). The instruction word is fetched in do_ri() and passed down to handlers. The handlers are called in sequence and return a result that lets the caller decide upon further processing. If the result is positive, then the handler has picked the instruction, but a signal should be thrown and the result is the signal number. If the result is zero, then the handler has successfully simulated the instruction. If the result is negative, then the handler did not handle the instruction; to make it more obvious the calls do not follow the usual 0/-Exxx result convention they now return -1 instead of -EFAULT. The calculation of the return EPC is now at the beginning. The reason is it is easier to handle it there as emulation callees may modify a register and an instruction may be located in delay slot of a branch whose result depends on the register. It has to be undone if a signal is to be raised, but it is not a problem as this is the slow-path case, and both actions are done in single places now rather than the former being scattered through emulation handlers. The part of do_cpu() being covered follows the changes to do_ri(). Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> ---
2007-10-17 01:43:26 +08:00
if (unlikely(get_user(opcode, epc) < 0))
status = SIGSEGV;
if (!cpu_has_llsc && status < 0)
status = simulate_llsc(regs, opcode);
if (status < 0)
status = simulate_rdhwr(regs, opcode);
if (status < 0)
status = SIGILL;
if (unlikely(status > 0)) {
regs->cp0_epc = old_epc; /* Undo skip-over. */
force_sig(status, current);
}
return;
case 1:
if (used_math()) /* Using the FPU again. */
own_fpu(1);
else { /* First time FPU user. */
init_fpu();
set_used_math();
}
if (!raw_cpu_has_fpu) {
int sig;
void __user *fault_addr = NULL;
sig = fpu_emulator_cop1Handler(regs,
&current->thread.fpu,
0, &fault_addr);
if (!process_fpemu_return(sig, fault_addr))
mt_ase_fp_affinity();
}
return;
case 2:
raw_notifier_call_chain(&cu2_chain, CU2_EXCEPTION, regs);
return;
case 3:
break;
}
force_sig(SIGILL, current);
}
asmlinkage void do_mdmx(struct pt_regs *regs)
{
force_sig(SIGILL, current);
}
/*
* Called with interrupts disabled.
*/
asmlinkage void do_watch(struct pt_regs *regs)
{
u32 cause;
/*
* Clear WP (bit 22) bit of cause register so we don't loop
* forever.
*/
cause = read_c0_cause();
cause &= ~(1 << 22);
write_c0_cause(cause);
/*
* If the current thread has the watch registers loaded, save
* their values and send SIGTRAP. Otherwise another thread
* left the registers set, clear them and continue.
*/
if (test_tsk_thread_flag(current, TIF_LOAD_WATCH)) {
mips_read_watch_registers();
local_irq_enable();
force_sig(SIGTRAP, current);
} else {
mips_clear_watch_registers();
local_irq_enable();
}
}
asmlinkage void do_mcheck(struct pt_regs *regs)
{
const int field = 2 * sizeof(unsigned long);
int multi_match = regs->cp0_status & ST0_TS;
show_regs(regs);
if (multi_match) {
printk("Index : %0x\n", read_c0_index());
printk("Pagemask: %0x\n", read_c0_pagemask());
printk("EntryHi : %0*lx\n", field, read_c0_entryhi());
printk("EntryLo0: %0*lx\n", field, read_c0_entrylo0());
printk("EntryLo1: %0*lx\n", field, read_c0_entrylo1());
printk("\n");
dump_tlb_all();
}
show_code((unsigned int __user *) regs->cp0_epc);
/*
* Some chips may have other causes of machine check (e.g. SB1
* graduation timer)
*/
panic("Caught Machine Check exception - %scaused by multiple "
"matching entries in the TLB.",
(multi_match) ? "" : "not ");
}
asmlinkage void do_mt(struct pt_regs *regs)
{
int subcode;
subcode = (read_vpe_c0_vpecontrol() & VPECONTROL_EXCPT)
>> VPECONTROL_EXCPT_SHIFT;
switch (subcode) {
case 0:
printk(KERN_DEBUG "Thread Underflow\n");
break;
case 1:
printk(KERN_DEBUG "Thread Overflow\n");
break;
case 2:
printk(KERN_DEBUG "Invalid YIELD Qualifier\n");
break;
case 3:
printk(KERN_DEBUG "Gating Storage Exception\n");
break;
case 4:
printk(KERN_DEBUG "YIELD Scheduler Exception\n");
break;
case 5:
printk(KERN_DEBUG "Gating Storage Scheduler Exception\n");
break;
default:
printk(KERN_DEBUG "*** UNKNOWN THREAD EXCEPTION %d ***\n",
subcode);
break;
}
die_if_kernel("MIPS MT Thread exception in kernel", regs);
force_sig(SIGILL, current);
}
asmlinkage void do_dsp(struct pt_regs *regs)
{
if (cpu_has_dsp)
panic("Unexpected DSP exception");
force_sig(SIGILL, current);
}
asmlinkage void do_reserved(struct pt_regs *regs)
{
/*
* Game over - no way to handle this if it ever occurs. Most probably
* caused by a new unknown cpu type or after another deadly
* hard/software error.
*/
show_regs(regs);
panic("Caught reserved exception %ld - should not happen.",
(regs->cp0_cause & 0x7f) >> 2);
}
static int __initdata l1parity = 1;
static int __init nol1parity(char *s)
{
l1parity = 0;
return 1;
}
__setup("nol1par", nol1parity);
static int __initdata l2parity = 1;
static int __init nol2parity(char *s)
{
l2parity = 0;
return 1;
}
__setup("nol2par", nol2parity);
/*
* Some MIPS CPUs can enable/disable for cache parity detection, but do
* it different ways.
*/
static inline void parity_protection_init(void)
{
switch (current_cpu_type()) {
case CPU_24K:
case CPU_34K:
case CPU_74K:
case CPU_1004K:
{
#define ERRCTL_PE 0x80000000
#define ERRCTL_L2P 0x00800000
unsigned long errctl;
unsigned int l1parity_present, l2parity_present;
errctl = read_c0_ecc();
errctl &= ~(ERRCTL_PE|ERRCTL_L2P);
/* probe L1 parity support */
write_c0_ecc(errctl | ERRCTL_PE);
back_to_back_c0_hazard();
l1parity_present = (read_c0_ecc() & ERRCTL_PE);
/* probe L2 parity support */
write_c0_ecc(errctl|ERRCTL_L2P);
back_to_back_c0_hazard();
l2parity_present = (read_c0_ecc() & ERRCTL_L2P);
if (l1parity_present && l2parity_present) {
if (l1parity)
errctl |= ERRCTL_PE;
if (l1parity ^ l2parity)
errctl |= ERRCTL_L2P;
} else if (l1parity_present) {
if (l1parity)
errctl |= ERRCTL_PE;
} else if (l2parity_present) {
if (l2parity)
errctl |= ERRCTL_L2P;
} else {
/* No parity available */
}
printk(KERN_INFO "Writing ErrCtl register=%08lx\n", errctl);
write_c0_ecc(errctl);
back_to_back_c0_hazard();
errctl = read_c0_ecc();
printk(KERN_INFO "Readback ErrCtl register=%08lx\n", errctl);
if (l1parity_present)
printk(KERN_INFO "Cache parity protection %sabled\n",
(errctl & ERRCTL_PE) ? "en" : "dis");
if (l2parity_present) {
if (l1parity_present && l1parity)
errctl ^= ERRCTL_L2P;
printk(KERN_INFO "L2 cache parity protection %sabled\n",
(errctl & ERRCTL_L2P) ? "en" : "dis");
}
}
break;
case CPU_5KC:
write_c0_ecc(0x80000000);
back_to_back_c0_hazard();
/* Set the PE bit (bit 31) in the c0_errctl register. */
printk(KERN_INFO "Cache parity protection %sabled\n",
(read_c0_ecc() & 0x80000000) ? "en" : "dis");
break;
case CPU_20KC:
case CPU_25KF:
/* Clear the DE bit (bit 16) in the c0_status register. */
printk(KERN_INFO "Enable cache parity protection for "
"MIPS 20KC/25KF CPUs.\n");
clear_c0_status(ST0_DE);
break;
default:
break;
}
}
asmlinkage void cache_parity_error(void)
{
const int field = 2 * sizeof(unsigned long);
unsigned int reg_val;
/* For the moment, report the problem and hang. */
printk("Cache error exception:\n");
printk("cp0_errorepc == %0*lx\n", field, read_c0_errorepc());
reg_val = read_c0_cacheerr();
printk("c0_cacheerr == %08x\n", reg_val);
printk("Decoded c0_cacheerr: %s cache fault in %s reference.\n",
reg_val & (1<<30) ? "secondary" : "primary",
reg_val & (1<<31) ? "data" : "insn");
printk("Error bits: %s%s%s%s%s%s%s\n",
reg_val & (1<<29) ? "ED " : "",
reg_val & (1<<28) ? "ET " : "",
reg_val & (1<<26) ? "EE " : "",
reg_val & (1<<25) ? "EB " : "",
reg_val & (1<<24) ? "EI " : "",
reg_val & (1<<23) ? "E1 " : "",
reg_val & (1<<22) ? "E0 " : "");
printk("IDX: 0x%08x\n", reg_val & ((1<<22)-1));
#if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64)
if (reg_val & (1<<22))
printk("DErrAddr0: 0x%0*lx\n", field, read_c0_derraddr0());
if (reg_val & (1<<23))
printk("DErrAddr1: 0x%0*lx\n", field, read_c0_derraddr1());
#endif
panic("Can't handle the cache error!");
}
/*
* SDBBP EJTAG debug exception handler.
* We skip the instruction and return to the next instruction.
*/
void ejtag_exception_handler(struct pt_regs *regs)
{
const int field = 2 * sizeof(unsigned long);
unsigned long depc, old_epc;
unsigned int debug;
printk(KERN_DEBUG "SDBBP EJTAG debug exception - not handled yet, just ignored!\n");
depc = read_c0_depc();
debug = read_c0_debug();
printk(KERN_DEBUG "c0_depc = %0*lx, DEBUG = %08x\n", field, depc, debug);
if (debug & 0x80000000) {
/*
* In branch delay slot.
* We cheat a little bit here and use EPC to calculate the
* debug return address (DEPC). EPC is restored after the
* calculation.
*/
old_epc = regs->cp0_epc;
regs->cp0_epc = depc;
__compute_return_epc(regs);
depc = regs->cp0_epc;
regs->cp0_epc = old_epc;
} else
depc += 4;
write_c0_depc(depc);
#if 0
printk(KERN_DEBUG "\n\n----- Enable EJTAG single stepping ----\n\n");
write_c0_debug(debug | 0x100);
#endif
}
/*
* NMI exception handler.
* No lock; only written during early bootup by CPU 0.
*/
static RAW_NOTIFIER_HEAD(nmi_chain);
int register_nmi_notifier(struct notifier_block *nb)
{
return raw_notifier_chain_register(&nmi_chain, nb);
}
void __noreturn nmi_exception_handler(struct pt_regs *regs)
{
raw_notifier_call_chain(&nmi_chain, 0, regs);
bust_spinlocks(1);
printk("NMI taken!!!!\n");
die("NMI", regs);
}
#define VECTORSPACING 0x100 /* for EI/VI mode */
unsigned long ebase;
unsigned long exception_handlers[32];
unsigned long vi_handlers[64];
void __init *set_except_vector(int n, void *addr)
{
unsigned long handler = (unsigned long) addr;
unsigned long old_handler = exception_handlers[n];
exception_handlers[n] = handler;
if (n == 0 && cpu_has_divec) {
unsigned long jump_mask = ~((1 << 28) - 1);
u32 *buf = (u32 *)(ebase + 0x200);
unsigned int k0 = 26;
if ((handler & jump_mask) == ((ebase + 0x200) & jump_mask)) {
uasm_i_j(&buf, handler & ~jump_mask);
uasm_i_nop(&buf);
} else {
UASM_i_LA(&buf, k0, handler);
uasm_i_jr(&buf, k0);
uasm_i_nop(&buf);
}
local_flush_icache_range(ebase + 0x200, (unsigned long)buf);
}
return (void *)old_handler;
}
static asmlinkage void do_default_vi(void)
{
show_regs(get_irq_regs());
panic("Caught unexpected vectored interrupt.");
}
static void *set_vi_srs_handler(int n, vi_handler_t addr, int srs)
{
unsigned long handler;
unsigned long old_handler = vi_handlers[n];
int srssets = current_cpu_data.srsets;
u32 *w;
unsigned char *b;
BUG_ON(!cpu_has_veic && !cpu_has_vint);
if (addr == NULL) {
handler = (unsigned long) do_default_vi;
srs = 0;
} else
handler = (unsigned long) addr;
vi_handlers[n] = (unsigned long) addr;
b = (unsigned char *)(ebase + 0x200 + n*VECTORSPACING);
if (srs >= srssets)
panic("Shadow register set %d not supported", srs);
if (cpu_has_veic) {
if (board_bind_eic_interrupt)
board_bind_eic_interrupt(n, srs);
} else if (cpu_has_vint) {
/* SRSMap is only defined if shadow sets are implemented */
if (srssets > 1)
change_c0_srsmap(0xf << n*4, srs << n*4);
}
if (srs == 0) {
/*
* If no shadow set is selected then use the default handler
* that does normal register saving and a standard interrupt exit
*/
extern char except_vec_vi, except_vec_vi_lui;
extern char except_vec_vi_ori, except_vec_vi_end;
extern char rollback_except_vec_vi;
char *vec_start = (cpu_wait == r4k_wait) ?
&rollback_except_vec_vi : &except_vec_vi;
#ifdef CONFIG_MIPS_MT_SMTC
/*
* We need to provide the SMTC vectored interrupt handler
* not only with the address of the handler, but with the
* Status.IM bit to be masked before going there.
*/
extern char except_vec_vi_mori;
const int mori_offset = &except_vec_vi_mori - vec_start;
#endif /* CONFIG_MIPS_MT_SMTC */
const int handler_len = &except_vec_vi_end - vec_start;
const int lui_offset = &except_vec_vi_lui - vec_start;
const int ori_offset = &except_vec_vi_ori - vec_start;
if (handler_len > VECTORSPACING) {
/*
* Sigh... panicing won't help as the console
* is probably not configured :(
*/
panic("VECTORSPACING too small");
}
memcpy(b, vec_start, handler_len);
#ifdef CONFIG_MIPS_MT_SMTC
BUG_ON(n > 7); /* Vector index %d exceeds SMTC maximum. */
w = (u32 *)(b + mori_offset);
*w = (*w & 0xffff0000) | (0x100 << n);
#endif /* CONFIG_MIPS_MT_SMTC */
w = (u32 *)(b + lui_offset);
*w = (*w & 0xffff0000) | (((u32)handler >> 16) & 0xffff);
w = (u32 *)(b + ori_offset);
*w = (*w & 0xffff0000) | ((u32)handler & 0xffff);
local_flush_icache_range((unsigned long)b,
(unsigned long)(b+handler_len));
}
else {
/*
* In other cases jump directly to the interrupt handler
*
* It is the handlers responsibility to save registers if required
* (eg hi/lo) and return from the exception using "eret"
*/
w = (u32 *)b;
*w++ = 0x08000000 | (((u32)handler >> 2) & 0x03fffff); /* j handler */
*w = 0;
local_flush_icache_range((unsigned long)b,
(unsigned long)(b+8));
}
return (void *)old_handler;
}
void *set_vi_handler(int n, vi_handler_t addr)
{
return set_vi_srs_handler(n, addr, 0);
}
extern void tlb_init(void);
extern void flush_tlb_handlers(void);
/*
* Timer interrupt
*/
int cp0_compare_irq;
int cp0_compare_irq_shift;
/*
* Performance counter IRQ or -1 if shared with timer
*/
int cp0_perfcount_irq;
EXPORT_SYMBOL_GPL(cp0_perfcount_irq);
static int __cpuinitdata noulri;
static int __init ulri_disable(char *s)
{
pr_info("Disabling ulri\n");
noulri = 1;
return 1;
}
__setup("noulri", ulri_disable);
void __cpuinit per_cpu_trap_init(bool is_boot_cpu)
{
unsigned int cpu = smp_processor_id();
unsigned int status_set = ST0_CU0;
unsigned int hwrena = cpu_hwrena_impl_bits;
#ifdef CONFIG_MIPS_MT_SMTC
int secondaryTC = 0;
int bootTC = (cpu == 0);
/*
* Only do per_cpu_trap_init() for first TC of Each VPE.
* Note that this hack assumes that the SMTC init code
* assigns TCs consecutively and in ascending order.
*/
if (((read_c0_tcbind() & TCBIND_CURTC) != 0) &&
((read_c0_tcbind() & TCBIND_CURVPE) == cpu_data[cpu - 1].vpe_id))
secondaryTC = 1;
#endif /* CONFIG_MIPS_MT_SMTC */
/*
* Disable coprocessors and select 32-bit or 64-bit addressing
* and the 16/32 or 32/32 FPR register model. Reset the BEV
* flag that some firmware may have left set and the TS bit (for
* IP27). Set XX for ISA IV code to work.
*/
#ifdef CONFIG_64BIT
status_set |= ST0_FR|ST0_KX|ST0_SX|ST0_UX;
#endif
if (current_cpu_data.isa_level == MIPS_CPU_ISA_IV)
status_set |= ST0_XX;
if (cpu_has_dsp)
status_set |= ST0_MX;
change_c0_status(ST0_CU|ST0_MX|ST0_RE|ST0_FR|ST0_BEV|ST0_TS|ST0_KX|ST0_SX|ST0_UX,
status_set);
if (cpu_has_mips_r2)
hwrena |= 0x0000000f;
if (!noulri && cpu_has_userlocal)
hwrena |= (1 << 29);
if (hwrena)
write_c0_hwrena(hwrena);
#ifdef CONFIG_MIPS_MT_SMTC
if (!secondaryTC) {
#endif /* CONFIG_MIPS_MT_SMTC */
if (cpu_has_veic || cpu_has_vint) {
unsigned long sr = set_c0_status(ST0_BEV);
write_c0_ebase(ebase);
write_c0_status(sr);
/* Setting vector spacing enables EI/VI mode */
change_c0_intctl(0x3e0, VECTORSPACING);
}
if (cpu_has_divec) {
if (cpu_has_mipsmt) {
unsigned int vpflags = dvpe();
set_c0_cause(CAUSEF_IV);
evpe(vpflags);
} else
set_c0_cause(CAUSEF_IV);
}
/*
* Before R2 both interrupt numbers were fixed to 7, so on R2 only:
*
* o read IntCtl.IPTI to determine the timer interrupt
* o read IntCtl.IPPCI to determine the performance counter interrupt
*/
if (cpu_has_mips_r2) {
cp0_compare_irq_shift = CAUSEB_TI - CAUSEB_IP;
cp0_compare_irq = (read_c0_intctl() >> INTCTLB_IPTI) & 7;
cp0_perfcount_irq = (read_c0_intctl() >> INTCTLB_IPPCI) & 7;
if (cp0_perfcount_irq == cp0_compare_irq)
cp0_perfcount_irq = -1;
} else {
cp0_compare_irq = CP0_LEGACY_COMPARE_IRQ;
cp0_compare_irq_shift = cp0_compare_irq;
cp0_perfcount_irq = -1;
}
#ifdef CONFIG_MIPS_MT_SMTC
}
#endif /* CONFIG_MIPS_MT_SMTC */
if (!cpu_data[cpu].asid_cache)
cpu_data[cpu].asid_cache = ASID_FIRST_VERSION;
atomic_inc(&init_mm.mm_count);
current->active_mm = &init_mm;
BUG_ON(current->mm);
enter_lazy_tlb(&init_mm, current);
#ifdef CONFIG_MIPS_MT_SMTC
if (bootTC) {
#endif /* CONFIG_MIPS_MT_SMTC */
/* Boot CPU's cache setup in setup_arch(). */
if (!is_boot_cpu)
cpu_cache_init();
tlb_init();
#ifdef CONFIG_MIPS_MT_SMTC
} else if (!secondaryTC) {
/*
* First TC in non-boot VPE must do subset of tlb_init()
* for MMU countrol registers.
*/
write_c0_pagemask(PM_DEFAULT_MASK);
write_c0_wired(0);
}
#endif /* CONFIG_MIPS_MT_SMTC */
TLBMISS_HANDLER_SETUP();
}
/* Install CPU exception handler */
void __cpuinit set_handler(unsigned long offset, void *addr, unsigned long size)
{
memcpy((void *)(ebase + offset), addr, size);
local_flush_icache_range(ebase + offset, ebase + offset + size);
}
static char panic_null_cerr[] __cpuinitdata =
"Trying to set NULL cache error exception handler";
/*
* Install uncached CPU exception handler.
* This is suitable only for the cache error exception which is the only
* exception handler that is being run uncached.
*/
void __cpuinit set_uncached_handler(unsigned long offset, void *addr,
unsigned long size)
{
unsigned long uncached_ebase = CKSEG1ADDR(ebase);
if (!addr)
panic(panic_null_cerr);
memcpy((void *)(uncached_ebase + offset), addr, size);
}
static int __initdata rdhwr_noopt;
static int __init set_rdhwr_noopt(char *str)
{
rdhwr_noopt = 1;
return 1;
}
__setup("rdhwr_noopt", set_rdhwr_noopt);
void __init trap_init(void)
{
extern char except_vec3_generic, except_vec3_r4000;
extern char except_vec4;
unsigned long i;
int rollback;
check_wait();
rollback = (cpu_wait == r4k_wait);
#if defined(CONFIG_KGDB)
if (kgdb_early_setup)
return; /* Already done */
#endif
if (cpu_has_veic || cpu_has_vint) {
unsigned long size = 0x200 + VECTORSPACING*64;
ebase = (unsigned long)
__alloc_bootmem(size, 1 << fls(size), 0);
} else {
ebase = CKSEG0;
if (cpu_has_mips_r2)
ebase += (read_c0_ebase() & 0x3ffff000);
}
if (board_ebase_setup)
board_ebase_setup();
per_cpu_trap_init(true);
/*
* Copy the generic exception handlers to their final destination.
* This will be overriden later as suitable for a particular
* configuration.
*/
set_handler(0x180, &except_vec3_generic, 0x80);
/*
* Setup default vectors
*/
for (i = 0; i <= 31; i++)
set_except_vector(i, handle_reserved);
/*
* Copy the EJTAG debug exception vector handler code to it's final
* destination.
*/
if (cpu_has_ejtag && board_ejtag_handler_setup)
board_ejtag_handler_setup();
/*
* Only some CPUs have the watch exceptions.
*/
if (cpu_has_watch)
set_except_vector(23, handle_watch);
/*
* Initialise interrupt handlers
*/
if (cpu_has_veic || cpu_has_vint) {
int nvec = cpu_has_veic ? 64 : 8;
for (i = 0; i < nvec; i++)
set_vi_handler(i, NULL);
}
else if (cpu_has_divec)
set_handler(0x200, &except_vec4, 0x8);
/*
* Some CPUs can enable/disable for cache parity detection, but does
* it different ways.
*/
parity_protection_init();
/*
* The Data Bus Errors / Instruction Bus Errors are signaled
* by external hardware. Therefore these two exceptions
* may have board specific handlers.
*/
if (board_be_init)
board_be_init();
set_except_vector(0, rollback ? rollback_handle_int : handle_int);
set_except_vector(1, handle_tlbm);
set_except_vector(2, handle_tlbl);
set_except_vector(3, handle_tlbs);
set_except_vector(4, handle_adel);
set_except_vector(5, handle_ades);
set_except_vector(6, handle_ibe);
set_except_vector(7, handle_dbe);
set_except_vector(8, handle_sys);
set_except_vector(9, handle_bp);
set_except_vector(10, rdhwr_noopt ? handle_ri :
(cpu_has_vtag_icache ?
handle_ri_rdhwr_vivt : handle_ri_rdhwr));
set_except_vector(11, handle_cpu);
set_except_vector(12, handle_ov);
set_except_vector(13, handle_tr);
if (current_cpu_type() == CPU_R6000 ||
current_cpu_type() == CPU_R6000A) {
/*
* The R6000 is the only R-series CPU that features a machine
* check exception (similar to the R4000 cache error) and
* unaligned ldc1/sdc1 exception. The handlers have not been
* written yet. Well, anyway there is no R6000 machine on the
* current list of targets for Linux/MIPS.
* (Duh, crap, there is someone with a triple R6k machine)
*/
//set_except_vector(14, handle_mc);
//set_except_vector(15, handle_ndc);
}
if (board_nmi_handler_setup)
board_nmi_handler_setup();
if (cpu_has_fpu && !cpu_has_nofpuex)
set_except_vector(15, handle_fpe);
set_except_vector(22, handle_mdmx);
if (cpu_has_mcheck)
set_except_vector(24, handle_mcheck);
if (cpu_has_mipsmt)
set_except_vector(25, handle_mt);
set_except_vector(26, handle_dsp);
if (board_cache_error_setup)
board_cache_error_setup();
if (cpu_has_vce)
/* Special exception: R4[04]00 uses also the divec space. */
memcpy((void *)(ebase + 0x180), &except_vec3_r4000, 0x100);
else if (cpu_has_4kex)
memcpy((void *)(ebase + 0x180), &except_vec3_generic, 0x80);
else
memcpy((void *)(ebase + 0x080), &except_vec3_generic, 0x80);
local_flush_icache_range(ebase, ebase + 0x400);
flush_tlb_handlers();
sort_extable(__start___dbe_table, __stop___dbe_table);
cu2_notifier(default_cu2_call, 0x80000000); /* Run last */
}