/* * PARISC Architecture-dependent parts of process handling * based on the work for i386 * * Copyright (C) 1999-2003 Matthew Wilcox <willy at parisc-linux.org> * Copyright (C) 2000 Martin K Petersen <mkp at mkp.net> * Copyright (C) 2000 John Marvin <jsm at parisc-linux.org> * Copyright (C) 2000 David Huggins-Daines <dhd with pobox.org> * Copyright (C) 2000-2003 Paul Bame <bame at parisc-linux.org> * Copyright (C) 2000 Philipp Rumpf <prumpf with tux.org> * Copyright (C) 2000 David Kennedy <dkennedy with linuxcare.com> * Copyright (C) 2000 Richard Hirst <rhirst with parisc-linux.org> * Copyright (C) 2000 Grant Grundler <grundler with parisc-linux.org> * Copyright (C) 2001 Alan Modra <amodra at parisc-linux.org> * Copyright (C) 2001-2002 Ryan Bradetich <rbrad at parisc-linux.org> * Copyright (C) 2001-2007 Helge Deller <deller at parisc-linux.org> * Copyright (C) 2002 Randolph Chung <tausq with parisc-linux.org> * * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include <stdarg.h> #include <linux/elf.h> #include <linux/errno.h> #include <linux/kernel.h> #include <linux/mm.h> #include <linux/fs.h> #include <linux/module.h> #include <linux/personality.h> #include <linux/ptrace.h> #include <linux/sched.h> #include <linux/slab.h> #include <linux/stddef.h> #include <linux/unistd.h> #include <linux/kallsyms.h> #include <linux/uaccess.h> #include <asm/io.h> #include <asm/asm-offsets.h> #include <asm/pdc.h> #include <asm/pdc_chassis.h> #include <asm/pgalloc.h> #include <asm/unwind.h> #include <asm/sections.h> /* * The idle thread. There's no useful work to be * done, so just try to conserve power and have a * low exit latency (ie sit in a loop waiting for * somebody to say that they'd like to reschedule) */ void cpu_idle(void) { set_thread_flag(TIF_POLLING_NRFLAG); /* endless idle loop with no priority at all */ while (1) { while (!need_resched()) barrier(); schedule_preempt_disabled(); check_pgt_cache(); } } #define COMMAND_GLOBAL F_EXTEND(0xfffe0030) #define CMD_RESET 5 /* reset any module */ /* ** The Wright Brothers and Gecko systems have a H/W problem ** (Lasi...'nuf said) may cause a broadcast reset to lockup ** the system. An HVERSION dependent PDC call was developed ** to perform a "safe", platform specific broadcast reset instead ** of kludging up all the code. ** ** Older machines which do not implement PDC_BROADCAST_RESET will ** return (with an error) and the regular broadcast reset can be ** issued. Obviously, if the PDC does implement PDC_BROADCAST_RESET ** the PDC call will not return (the system will be reset). */ void machine_restart(char *cmd) { #ifdef FASTBOOT_SELFTEST_SUPPORT /* ** If user has modified the Firmware Selftest Bitmap, ** run the tests specified in the bitmap after the ** system is rebooted w/PDC_DO_RESET. ** ** ftc_bitmap = 0x1AUL "Skip destructive memory tests" ** ** Using "directed resets" at each processor with the MEM_TOC ** vector cleared will also avoid running destructive ** memory self tests. (Not implemented yet) */ if (ftc_bitmap) { pdc_do_firm_test_reset(ftc_bitmap); } #endif /* set up a new led state on systems shipped with a LED State panel */ pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN); /* "Normal" system reset */ pdc_do_reset(); /* Nope...box should reset with just CMD_RESET now */ gsc_writel(CMD_RESET, COMMAND_GLOBAL); /* Wait for RESET to lay us to rest. */ while (1) ; } void machine_halt(void) { /* ** The LED/ChassisCodes are updated by the led_halt() ** function, called by the reboot notifier chain. */ } void (*chassis_power_off)(void); /* * This routine is called from sys_reboot to actually turn off the * machine */ void machine_power_off(void) { /* If there is a registered power off handler, call it. */ if (chassis_power_off) chassis_power_off(); /* Put the soft power button back under hardware control. * If the user had already pressed the power button, the * following call will immediately power off. */ pdc_soft_power_button(0); pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN); /* It seems we have no way to power the system off via * software. The user has to press the button himself. */ printk(KERN_EMERG "System shut down completed.\n" "Please power this system off now."); } void (*pm_power_off)(void) = machine_power_off; EXPORT_SYMBOL(pm_power_off); /* * Create a kernel thread */ extern pid_t __kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) { /* * FIXME: Once we are sure we don't need any debug here, * kernel_thread can become a #define. */ return __kernel_thread(fn, arg, flags); } EXPORT_SYMBOL(kernel_thread); /* * Free current thread data structures etc.. */ void exit_thread(void) { } void flush_thread(void) { /* Only needs to handle fpu stuff or perf monitors. ** REVISIT: several arches implement a "lazy fpu state". */ } void release_thread(struct task_struct *dead_task) { } /* * Fill in the FPU structure for a core dump. */ int dump_fpu (struct pt_regs * regs, elf_fpregset_t *r) { if (regs == NULL) return 0; memcpy(r, regs->fr, sizeof *r); return 1; } int dump_task_fpu (struct task_struct *tsk, elf_fpregset_t *r) { memcpy(r, tsk->thread.regs.fr, sizeof(*r)); return 1; } /* Note that "fork()" is implemented in terms of clone, with parameters (SIGCHLD, regs->gr[30], regs). */ int sys_clone(unsigned long clone_flags, unsigned long usp, struct pt_regs *regs) { /* Arugments from userspace are: r26 = Clone flags. r25 = Child stack. r24 = parent_tidptr. r23 = Is the TLS storage descriptor r22 = child_tidptr However, these last 3 args are only examined if the proper flags are set. */ int __user *parent_tidptr = (int __user *)regs->gr[24]; int __user *child_tidptr = (int __user *)regs->gr[22]; /* usp must be word aligned. This also prevents users from * passing in the value 1 (which is the signal for a special * return for a kernel thread) */ usp = ALIGN(usp, 4); /* A zero value for usp means use the current stack */ if (usp == 0) usp = regs->gr[30]; return do_fork(clone_flags, usp, regs, 0, parent_tidptr, child_tidptr); } int sys_vfork(struct pt_regs *regs) { return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gr[30], regs, 0, NULL, NULL); } int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long unused, /* in ia64 this is "user_stack_size" */ struct task_struct * p, struct pt_regs * pregs) { struct pt_regs * cregs = &(p->thread.regs); void *stack = task_stack_page(p); /* We have to use void * instead of a function pointer, because * function pointers aren't a pointer to the function on 64-bit. * Make them const so the compiler knows they live in .text */ extern void * const ret_from_kernel_thread; extern void * const child_return; #ifdef CONFIG_HPUX extern void * const hpux_child_return; #endif *cregs = *pregs; /* Set the return value for the child. Note that this is not actually restored by the syscall exit path, but we put it here for consistency in case of signals. */ cregs->gr[28] = 0; /* child */ /* * We need to differentiate between a user fork and a * kernel fork. We can't use user_mode, because the * the syscall path doesn't save iaoq. Right now * We rely on the fact that kernel_thread passes * in zero for usp. */ if (usp == 1) { /* kernel thread */ cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN; /* Must exit via ret_from_kernel_thread in order * to call schedule_tail() */ cregs->kpc = (unsigned long) &ret_from_kernel_thread; /* * Copy function and argument to be called from * ret_from_kernel_thread. */ #ifdef CONFIG_64BIT cregs->gr[27] = pregs->gr[27]; #endif cregs->gr[26] = pregs->gr[26]; cregs->gr[25] = pregs->gr[25]; } else { /* user thread */ /* * Note that the fork wrappers are responsible * for setting gr[21]. */ /* Use same stack depth as parent */ cregs->ksp = (unsigned long)stack + (pregs->gr[21] & (THREAD_SIZE - 1)); cregs->gr[30] = usp; if (p->personality == PER_HPUX) { #ifdef CONFIG_HPUX cregs->kpc = (unsigned long) &hpux_child_return; #else BUG(); #endif } else { cregs->kpc = (unsigned long) &child_return; } /* Setup thread TLS area from the 4th parameter in clone */ if (clone_flags & CLONE_SETTLS) cregs->cr27 = pregs->gr[23]; } return 0; } unsigned long thread_saved_pc(struct task_struct *t) { return t->thread.regs.kpc; } /* * sys_execve() executes a new program. */ asmlinkage int sys_execve(struct pt_regs *regs) { int error; char *filename; filename = getname((const char __user *) regs->gr[26]); error = PTR_ERR(filename); if (IS_ERR(filename)) goto out; error = do_execve(filename, (const char __user *const __user *) regs->gr[25], (const char __user *const __user *) regs->gr[24], regs); putname(filename); out: return error; } extern int __execve(const char *filename, const char *const argv[], const char *const envp[], struct task_struct *task); int kernel_execve(const char *filename, const char *const argv[], const char *const envp[]) { return __execve(filename, argv, envp, current); } unsigned long get_wchan(struct task_struct *p) { struct unwind_frame_info info; unsigned long ip; int count = 0; if (!p || p == current || p->state == TASK_RUNNING) return 0; /* * These bracket the sleeping functions.. */ unwind_frame_init_from_blocked_task(&info, p); do { if (unwind_once(&info) < 0) return 0; ip = info.ip; if (!in_sched_functions(ip)) return ip; } while (count++ < 16); return 0; } #ifdef CONFIG_64BIT void *dereference_function_descriptor(void *ptr) { Elf64_Fdesc *desc = ptr; void *p; if (!probe_kernel_address(&desc->addr, p)) ptr = p; return ptr; } #endif