292 lines
7.3 KiB
C
292 lines
7.3 KiB
C
|
/*
|
||
|
|
* pseries CPU Hotplug infrastructure.
|
||
|
|
*
|
||
|
|
* Split out from arch/powerpc/platforms/pseries/setup.c
|
||
|
|
* arch/powerpc/kernel/rtas.c, and arch/powerpc/platforms/pseries/smp.c
|
||
|
|
*
|
||
|
|
* Peter Bergner, IBM March 2001.
|
||
|
|
* Copyright (C) 2001 IBM.
|
||
|
|
* Dave Engebretsen, Peter Bergner, and
|
||
|
|
* Mike Corrigan {engebret|bergner|mikec}@us.ibm.com
|
||
|
|
* Plus various changes from other IBM teams...
|
||
|
|
*
|
||
|
|
* Copyright (C) 2006 Michael Ellerman, IBM Corporation
|
||
|
|
*
|
||
|
|
* 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/delay.h>
|
||
|
|
#include <linux/cpu.h>
|
||
|
|
#include <asm/system.h>
|
||
|
|
#include <asm/prom.h>
|
||
|
|
#include <asm/rtas.h>
|
||
|
|
#include <asm/firmware.h>
|
||
|
|
#include <asm/machdep.h>
|
||
|
|
#include <asm/vdso_datapage.h>
|
||
|
|
#include <asm/pSeries_reconfig.h>
|
||
|
|
#include "xics.h"
|
||
|
|
#include "plpar_wrappers.h"
|
||
|
|
|
||
|
|
/* This version can't take the spinlock, because it never returns */
|
||
|
|
static struct rtas_args rtas_stop_self_args = {
|
||
|
|
.token = RTAS_UNKNOWN_SERVICE,
|
||
|
|
.nargs = 0,
|
||
|
|
.nret = 1,
|
||
|
|
.rets = &rtas_stop_self_args.args[0],
|
||
|
|
};
|
||
|
|
|
||
|
|
static void rtas_stop_self(void)
|
||
|
|
{
|
||
|
|
struct rtas_args *args = &rtas_stop_self_args;
|
||
|
|
|
||
|
|
local_irq_disable();
|
||
|
|
|
||
|
|
BUG_ON(args->token == RTAS_UNKNOWN_SERVICE);
|
||
|
|
|
||
|
|
printk("cpu %u (hwid %u) Ready to die...\n",
|
||
|
|
smp_processor_id(), hard_smp_processor_id());
|
||
|
|
enter_rtas(__pa(args));
|
||
|
|
|
||
|
|
panic("Alas, I survived.\n");
|
||
|
|
}
|
||
|
|
|
||
|
|
static void pseries_mach_cpu_die(void)
|
||
|
|
{
|
||
|
|
local_irq_disable();
|
||
|
|
idle_task_exit();
|
||
|
|
xics_teardown_cpu();
|
||
|
|
unregister_slb_shadow(hard_smp_processor_id(), __pa(get_slb_shadow()));
|
||
|
|
rtas_stop_self();
|
||
|
|
/* Should never get here... */
|
||
|
|
BUG();
|
||
|
|
for(;;);
|
||
|
|
}
|
||
|
|
|
||
|
|
static int qcss_tok; /* query-cpu-stopped-state token */
|
||
|
|
|
||
|
|
/* Get state of physical CPU.
|
||
|
|
* Return codes:
|
||
|
|
* 0 - The processor is in the RTAS stopped state
|
||
|
|
* 1 - stop-self is in progress
|
||
|
|
* 2 - The processor is not in the RTAS stopped state
|
||
|
|
* -1 - Hardware Error
|
||
|
|
* -2 - Hardware Busy, Try again later.
|
||
|
|
*/
|
||
|
|
static int query_cpu_stopped(unsigned int pcpu)
|
||
|
|
{
|
||
|
|
int cpu_status, status;
|
||
|
|
|
||
|
|
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;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int pseries_cpu_disable(void)
|
||
|
|
{
|
||
|
|
int cpu = smp_processor_id();
|
||
|
|
|
||
|
|
set_cpu_online(cpu, false);
|
||
|
|
vdso_data->processorCount--;
|
||
|
|
|
||
|
|
/*fix boot_cpuid here*/
|
||
|
|
if (cpu == boot_cpuid)
|
||
|
|
boot_cpuid = any_online_cpu(cpu_online_map);
|
||
|
|
|
||
|
|
/* FIXME: abstract this to not be platform specific later on */
|
||
|
|
xics_migrate_irqs_away();
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void pseries_cpu_die(unsigned int cpu)
|
||
|
|
{
|
||
|
|
int tries;
|
||
|
|
int cpu_status;
|
||
|
|
unsigned int pcpu = get_hard_smp_processor_id(cpu);
|
||
|
|
|
||
|
|
for (tries = 0; tries < 25; tries++) {
|
||
|
|
cpu_status = query_cpu_stopped(pcpu);
|
||
|
|
if (cpu_status == 0 || cpu_status == -1)
|
||
|
|
break;
|
||
|
|
cpu_relax();
|
||
|
|
}
|
||
|
|
if (cpu_status != 0) {
|
||
|
|
printk("Querying DEAD? cpu %i (%i) shows %i\n",
|
||
|
|
cpu, pcpu, cpu_status);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Isolation and deallocation are definatly done by
|
||
|
|
* drslot_chrp_cpu. If they were not they would be
|
||
|
|
* done here. Change isolate state to Isolate and
|
||
|
|
* change allocation-state to Unusable.
|
||
|
|
*/
|
||
|
|
paca[cpu].cpu_start = 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Update cpu_present_map and paca(s) for a new cpu node. The wrinkle
|
||
|
|
* here is that a cpu device node may represent up to two logical cpus
|
||
|
|
* in the SMT case. We must honor the assumption in other code that
|
||
|
|
* the logical ids for sibling SMT threads x and y are adjacent, such
|
||
|
|
* that x^1 == y and y^1 == x.
|
||
|
|
*/
|
||
|
|
static int pseries_add_processor(struct device_node *np)
|
||
|
|
{
|
||
|
|
unsigned int cpu;
|
||
|
|
cpumask_t candidate_map, tmp = CPU_MASK_NONE;
|
||
|
|
int err = -ENOSPC, len, nthreads, i;
|
||
|
|
const u32 *intserv;
|
||
|
|
|
||
|
|
intserv = of_get_property(np, "ibm,ppc-interrupt-server#s", &len);
|
||
|
|
if (!intserv)
|
||
|
|
return 0;
|
||
|
|
|
||
|
|
nthreads = len / sizeof(u32);
|
||
|
|
for (i = 0; i < nthreads; i++)
|
||
|
|
cpu_set(i, tmp);
|
||
|
|
|
||
|
|
cpu_maps_update_begin();
|
||
|
|
|
||
|
|
BUG_ON(!cpus_subset(cpu_present_map, cpu_possible_map));
|
||
|
|
|
||
|
|
/* Get a bitmap of unoccupied slots. */
|
||
|
|
cpus_xor(candidate_map, cpu_possible_map, cpu_present_map);
|
||
|
|
if (cpus_empty(candidate_map)) {
|
||
|
|
/* If we get here, it most likely means that NR_CPUS is
|
||
|
|
* less than the partition's max processors setting.
|
||
|
|
*/
|
||
|
|
printk(KERN_ERR "Cannot add cpu %s; this system configuration"
|
||
|
|
" supports %d logical cpus.\n", np->full_name,
|
||
|
|
cpus_weight(cpu_possible_map));
|
||
|
|
goto out_unlock;
|
||
|
|
}
|
||
|
|
|
||
|
|
while (!cpus_empty(tmp))
|
||
|
|
if (cpus_subset(tmp, candidate_map))
|
||
|
|
/* Found a range where we can insert the new cpu(s) */
|
||
|
|
break;
|
||
|
|
else
|
||
|
|
cpus_shift_left(tmp, tmp, nthreads);
|
||
|
|
|
||
|
|
if (cpus_empty(tmp)) {
|
||
|
|
printk(KERN_ERR "Unable to find space in cpu_present_map for"
|
||
|
|
" processor %s with %d thread(s)\n", np->name,
|
||
|
|
nthreads);
|
||
|
|
goto out_unlock;
|
||
|
|
}
|
||
|
|
|
||
|
|
for_each_cpu_mask(cpu, tmp) {
|
||
|
|
BUG_ON(cpu_isset(cpu, cpu_present_map));
|
||
|
|
set_cpu_present(cpu, true);
|
||
|
|
set_hard_smp_processor_id(cpu, *intserv++);
|
||
|
|
}
|
||
|
|
err = 0;
|
||
|
|
out_unlock:
|
||
|
|
cpu_maps_update_done();
|
||
|
|
return err;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Update the present map for a cpu node which is going away, and set
|
||
|
|
* the hard id in the paca(s) to -1 to be consistent with boot time
|
||
|
|
* convention for non-present cpus.
|
||
|
|
*/
|
||
|
|
static void pseries_remove_processor(struct device_node *np)
|
||
|
|
{
|
||
|
|
unsigned int cpu;
|
||
|
|
int len, nthreads, i;
|
||
|
|
const u32 *intserv;
|
||
|
|
|
||
|
|
intserv = of_get_property(np, "ibm,ppc-interrupt-server#s", &len);
|
||
|
|
if (!intserv)
|
||
|
|
return;
|
||
|
|
|
||
|
|
nthreads = len / sizeof(u32);
|
||
|
|
|
||
|
|
cpu_maps_update_begin();
|
||
|
|
for (i = 0; i < nthreads; i++) {
|
||
|
|
for_each_present_cpu(cpu) {
|
||
|
|
if (get_hard_smp_processor_id(cpu) != intserv[i])
|
||
|
|
continue;
|
||
|
|
BUG_ON(cpu_online(cpu));
|
||
|
|
set_cpu_present(cpu, false);
|
||
|
|
set_hard_smp_processor_id(cpu, -1);
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
if (cpu == NR_CPUS)
|
||
|
|
printk(KERN_WARNING "Could not find cpu to remove "
|
||
|
|
"with physical id 0x%x\n", intserv[i]);
|
||
|
|
}
|
||
|
|
cpu_maps_update_done();
|
||
|
|
}
|
||
|
|
|
||
|
|
static int pseries_smp_notifier(struct notifier_block *nb,
|
||
|
|
unsigned long action, void *node)
|
||
|
|
{
|
||
|
|
int err = NOTIFY_OK;
|
||
|
|
|
||
|
|
switch (action) {
|
||
|
|
case PSERIES_RECONFIG_ADD:
|
||
|
|
if (pseries_add_processor(node))
|
||
|
|
err = NOTIFY_BAD;
|
||
|
|
break;
|
||
|
|
case PSERIES_RECONFIG_REMOVE:
|
||
|
|
pseries_remove_processor(node);
|
||
|
|
break;
|
||
|
|
default:
|
||
|
|
err = NOTIFY_DONE;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
return err;
|
||
|
|
}
|
||
|
|
|
||
|
|
static struct notifier_block pseries_smp_nb = {
|
||
|
|
.notifier_call = pseries_smp_notifier,
|
||
|
|
};
|
||
|
|
|
||
|
|
static int __init pseries_cpu_hotplug_init(void)
|
||
|
|
{
|
||
|
|
struct device_node *np;
|
||
|
|
const char *typep;
|
||
|
|
|
||
|
|
for_each_node_by_name(np, "interrupt-controller") {
|
||
|
|
typep = of_get_property(np, "compatible", NULL);
|
||
|
|
if (strstr(typep, "open-pic")) {
|
||
|
|
of_node_put(np);
|
||
|
|
|
||
|
|
printk(KERN_INFO "CPU Hotplug not supported on "
|
||
|
|
"systems using MPIC\n");
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
rtas_stop_self_args.token = rtas_token("stop-self");
|
||
|
|
qcss_tok = rtas_token("query-cpu-stopped-state");
|
||
|
|
|
||
|
|
if (rtas_stop_self_args.token == RTAS_UNKNOWN_SERVICE ||
|
||
|
|
qcss_tok == RTAS_UNKNOWN_SERVICE) {
|
||
|
|
printk(KERN_INFO "CPU Hotplug not supported by firmware "
|
||
|
|
"- disabling.\n");
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
ppc_md.cpu_die = pseries_mach_cpu_die;
|
||
|
|
smp_ops->cpu_disable = pseries_cpu_disable;
|
||
|
|
smp_ops->cpu_die = pseries_cpu_die;
|
||
|
|
|
||
|
|
/* Processors can be added/removed only on LPAR */
|
||
|
|
if (firmware_has_feature(FW_FEATURE_LPAR))
|
||
|
|
pSeries_reconfig_notifier_register(&pseries_smp_nb);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
arch_initcall(pseries_cpu_hotplug_init);
|