mirror of https://gitee.com/openkylin/linux.git
270 lines
6.5 KiB
C
270 lines
6.5 KiB
C
/*
|
|
* SMP support for pSeries machines.
|
|
*
|
|
* Dave Engebretsen, Peter Bergner, and
|
|
* Mike Corrigan {engebret|bergner|mikec}@us.ibm.com
|
|
*
|
|
* Plus various changes from other IBM teams...
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/smp.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/init.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/cache.h>
|
|
#include <linux/err.h>
|
|
#include <linux/device.h>
|
|
#include <linux/cpu.h>
|
|
|
|
#include <asm/ptrace.h>
|
|
#include <linux/atomic.h>
|
|
#include <asm/irq.h>
|
|
#include <asm/page.h>
|
|
#include <asm/pgtable.h>
|
|
#include <asm/io.h>
|
|
#include <asm/prom.h>
|
|
#include <asm/smp.h>
|
|
#include <asm/paca.h>
|
|
#include <asm/machdep.h>
|
|
#include <asm/cputable.h>
|
|
#include <asm/firmware.h>
|
|
#include <asm/rtas.h>
|
|
#include <asm/mpic.h>
|
|
#include <asm/vdso_datapage.h>
|
|
#include <asm/cputhreads.h>
|
|
#include <asm/xics.h>
|
|
#include <asm/dbell.h>
|
|
#include <asm/plpar_wrappers.h>
|
|
|
|
#include "pseries.h"
|
|
#include "offline_states.h"
|
|
|
|
|
|
/*
|
|
* The Primary thread of each non-boot processor was started from the OF client
|
|
* interface by prom_hold_cpus and is spinning on secondary_hold_spinloop.
|
|
*/
|
|
static cpumask_var_t of_spin_mask;
|
|
|
|
/*
|
|
* If we multiplex IPI mechanisms, store the appropriate XICS IPI mechanism here
|
|
*/
|
|
static void (*xics_cause_ipi)(int cpu, unsigned long data);
|
|
|
|
/* Query where a cpu is now. Return codes #defined in plpar_wrappers.h */
|
|
int smp_query_cpu_stopped(unsigned int pcpu)
|
|
{
|
|
int cpu_status, status;
|
|
int qcss_tok = rtas_token("query-cpu-stopped-state");
|
|
|
|
if (qcss_tok == RTAS_UNKNOWN_SERVICE) {
|
|
printk_once(KERN_INFO
|
|
"Firmware doesn't support query-cpu-stopped-state\n");
|
|
return QCSS_HARDWARE_ERROR;
|
|
}
|
|
|
|
status = rtas_call(qcss_tok, 1, 2, &cpu_status, pcpu);
|
|
if (status != 0) {
|
|
printk(KERN_ERR
|
|
"RTAS query-cpu-stopped-state failed: %i\n", status);
|
|
return status;
|
|
}
|
|
|
|
return cpu_status;
|
|
}
|
|
|
|
/**
|
|
* smp_startup_cpu() - start the given cpu
|
|
*
|
|
* At boot time, there is nothing to do for primary threads which were
|
|
* started from Open Firmware. For anything else, call RTAS with the
|
|
* appropriate start location.
|
|
*
|
|
* Returns:
|
|
* 0 - failure
|
|
* 1 - success
|
|
*/
|
|
static inline int smp_startup_cpu(unsigned int lcpu)
|
|
{
|
|
int status;
|
|
unsigned long start_here = __pa((u32)*((unsigned long *)
|
|
generic_secondary_smp_init));
|
|
unsigned int pcpu;
|
|
int start_cpu;
|
|
|
|
if (cpumask_test_cpu(lcpu, of_spin_mask))
|
|
/* Already started by OF and sitting in spin loop */
|
|
return 1;
|
|
|
|
pcpu = get_hard_smp_processor_id(lcpu);
|
|
|
|
/* Check to see if the CPU out of FW already for kexec */
|
|
if (smp_query_cpu_stopped(pcpu) == QCSS_NOT_STOPPED){
|
|
cpumask_set_cpu(lcpu, of_spin_mask);
|
|
return 1;
|
|
}
|
|
|
|
/* Fixup atomic count: it exited inside IRQ handler. */
|
|
task_thread_info(paca[lcpu].__current)->preempt_count = 0;
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
if (get_cpu_current_state(lcpu) == CPU_STATE_INACTIVE)
|
|
goto out;
|
|
#endif
|
|
/*
|
|
* If the RTAS start-cpu token does not exist then presume the
|
|
* cpu is already spinning.
|
|
*/
|
|
start_cpu = rtas_token("start-cpu");
|
|
if (start_cpu == RTAS_UNKNOWN_SERVICE)
|
|
return 1;
|
|
|
|
status = rtas_call(start_cpu, 3, 1, NULL, pcpu, start_here, pcpu);
|
|
if (status != 0) {
|
|
printk(KERN_ERR "start-cpu failed: %i\n", status);
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
out:
|
|
#endif
|
|
return 1;
|
|
}
|
|
|
|
static void smp_xics_setup_cpu(int cpu)
|
|
{
|
|
if (cpu != boot_cpuid)
|
|
xics_setup_cpu();
|
|
if (cpu_has_feature(CPU_FTR_DBELL))
|
|
doorbell_setup_this_cpu();
|
|
|
|
if (firmware_has_feature(FW_FEATURE_SPLPAR))
|
|
vpa_init(cpu);
|
|
|
|
cpumask_clear_cpu(cpu, of_spin_mask);
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
set_cpu_current_state(cpu, CPU_STATE_ONLINE);
|
|
set_default_offline_state(cpu);
|
|
#endif
|
|
}
|
|
|
|
static int smp_pSeries_kick_cpu(int nr)
|
|
{
|
|
BUG_ON(nr < 0 || nr >= NR_CPUS);
|
|
|
|
if (!smp_startup_cpu(nr))
|
|
return -ENOENT;
|
|
|
|
/*
|
|
* The processor is currently spinning, waiting for the
|
|
* cpu_start field to become non-zero After we set cpu_start,
|
|
* the processor will continue on to secondary_start
|
|
*/
|
|
paca[nr].cpu_start = 1;
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
set_preferred_offline_state(nr, CPU_STATE_ONLINE);
|
|
|
|
if (get_cpu_current_state(nr) == CPU_STATE_INACTIVE) {
|
|
long rc;
|
|
unsigned long hcpuid;
|
|
|
|
hcpuid = get_hard_smp_processor_id(nr);
|
|
rc = plpar_hcall_norets(H_PROD, hcpuid);
|
|
if (rc != H_SUCCESS)
|
|
printk(KERN_ERR "Error: Prod to wake up processor %d "
|
|
"Ret= %ld\n", nr, rc);
|
|
}
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Only used on systems that support multiple IPI mechanisms */
|
|
static void pSeries_cause_ipi_mux(int cpu, unsigned long data)
|
|
{
|
|
if (cpumask_test_cpu(cpu, cpu_sibling_mask(smp_processor_id())))
|
|
doorbell_cause_ipi(cpu, data);
|
|
else
|
|
xics_cause_ipi(cpu, data);
|
|
}
|
|
|
|
static __init int pSeries_smp_probe(void)
|
|
{
|
|
int ret = xics_smp_probe();
|
|
|
|
if (cpu_has_feature(CPU_FTR_DBELL)) {
|
|
xics_cause_ipi = smp_ops->cause_ipi;
|
|
smp_ops->cause_ipi = pSeries_cause_ipi_mux;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static struct smp_ops_t pSeries_mpic_smp_ops = {
|
|
.message_pass = smp_mpic_message_pass,
|
|
.probe = smp_mpic_probe,
|
|
.kick_cpu = smp_pSeries_kick_cpu,
|
|
.setup_cpu = smp_mpic_setup_cpu,
|
|
};
|
|
|
|
static struct smp_ops_t pSeries_xics_smp_ops = {
|
|
.message_pass = NULL, /* Use smp_muxed_ipi_message_pass */
|
|
.cause_ipi = NULL, /* Filled at runtime by pSeries_smp_probe() */
|
|
.probe = pSeries_smp_probe,
|
|
.kick_cpu = smp_pSeries_kick_cpu,
|
|
.setup_cpu = smp_xics_setup_cpu,
|
|
.cpu_bootable = smp_generic_cpu_bootable,
|
|
};
|
|
|
|
/* This is called very early */
|
|
static void __init smp_init_pseries(void)
|
|
{
|
|
int i;
|
|
|
|
pr_debug(" -> smp_init_pSeries()\n");
|
|
|
|
alloc_bootmem_cpumask_var(&of_spin_mask);
|
|
|
|
/* Mark threads which are still spinning in hold loops. */
|
|
if (cpu_has_feature(CPU_FTR_SMT)) {
|
|
for_each_present_cpu(i) {
|
|
if (cpu_thread_in_core(i) == 0)
|
|
cpumask_set_cpu(i, of_spin_mask);
|
|
}
|
|
} else {
|
|
cpumask_copy(of_spin_mask, cpu_present_mask);
|
|
}
|
|
|
|
cpumask_clear_cpu(boot_cpuid, of_spin_mask);
|
|
|
|
/* Non-lpar has additional take/give timebase */
|
|
if (rtas_token("freeze-time-base") != RTAS_UNKNOWN_SERVICE) {
|
|
smp_ops->give_timebase = rtas_give_timebase;
|
|
smp_ops->take_timebase = rtas_take_timebase;
|
|
}
|
|
|
|
pr_debug(" <- smp_init_pSeries()\n");
|
|
}
|
|
|
|
void __init smp_init_pseries_mpic(void)
|
|
{
|
|
smp_ops = &pSeries_mpic_smp_ops;
|
|
|
|
smp_init_pseries();
|
|
}
|
|
|
|
void __init smp_init_pseries_xics(void)
|
|
{
|
|
smp_ops = &pSeries_xics_smp_ops;
|
|
|
|
smp_init_pseries();
|
|
}
|