[PATCH 4/9] powerpc/85xx: support CPU hotplug for e500mc and e5500
Chenhui Zhao
chenhui.zhao at freescale.com
Fri Mar 7 15:58:00 EST 2014
Implemented CPU hotplug on e500mc and e5500. On e5500 both 32-bit and
64-bit modes can work. Used some callback functions implemented in RCPM
driver.
Signed-off-by: Chenhui Zhao <chenhui.zhao at freescale.com>
---
arch/powerpc/Kconfig | 2 +-
arch/powerpc/kernel/smp.c | 6 ++-
arch/powerpc/mm/tlb_nohash.c | 6 ++-
arch/powerpc/platforms/85xx/smp.c | 94 ++++++++++++++++++++++++++++++-------
4 files changed, 87 insertions(+), 21 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index a5e5d2e..05f6323 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -362,7 +362,7 @@ config SWIOTLB
config HOTPLUG_CPU
bool "Support for enabling/disabling CPUs"
depends on SMP && (PPC_PSERIES || \
- PPC_PMAC || PPC_POWERNV || (PPC_85xx && !PPC_E500MC))
+ PPC_PMAC || PPC_POWERNV || FSL_SOC_BOOKE)
---help---
Say Y here to be able to disable and re-enable individual
CPUs at runtime on SMP machines.
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index ac2621a..f3f4401 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -405,8 +405,12 @@ void generic_cpu_die(unsigned int cpu)
for (i = 0; i < 100; i++) {
smp_rmb();
- if (per_cpu(cpu_state, cpu) == CPU_DEAD)
+ if (per_cpu(cpu_state, cpu) == CPU_DEAD) {
+#ifdef CONFIG_PPC64
+ paca[cpu].cpu_start = 0;
+#endif
return;
+ }
msleep(100);
}
printk(KERN_ERR "CPU%d didn't die...\n", cpu);
diff --git a/arch/powerpc/mm/tlb_nohash.c b/arch/powerpc/mm/tlb_nohash.c
index b37a58e..d24e06c 100644
--- a/arch/powerpc/mm/tlb_nohash.c
+++ b/arch/powerpc/mm/tlb_nohash.c
@@ -648,8 +648,10 @@ static void __early_init_mmu(int boot_cpu)
num_cams = (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) / 4;
linear_map_top = map_mem_in_cams(linear_map_top, num_cams);
- /* limit memory so we dont have linear faults */
- memblock_enforce_memory_limit(linear_map_top);
+ if (boot_cpu) {
+ /* limit memory so we dont have linear faults */
+ memblock_enforce_memory_limit(linear_map_top);
+ }
if (book3e_htw_mode == PPC_HTW_NONE) {
patch_exception(0x1c0, exc_data_tlb_miss_bolted_book3e);
diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c
index 2e5911e..0047883 100644
--- a/arch/powerpc/platforms/85xx/smp.c
+++ b/arch/powerpc/platforms/85xx/smp.c
@@ -19,6 +19,7 @@
#include <linux/kexec.h>
#include <linux/highmem.h>
#include <linux/cpu.h>
+#include <linux/smp.h>
#include <asm/machdep.h>
#include <asm/pgtable.h>
@@ -46,6 +47,17 @@ static u64 timebase;
static int tb_req;
static int tb_valid;
+#ifdef CONFIG_PPC_E500MC
+/* specify the cpu PM state when cpu dies, PH15/NAP is the default */
+int qoriq_cpu_die_state = E500_PM_PH15;
+#endif
+
+#ifdef CONFIG_PPC_E500MC
+static void mpc85xx_timebase_freeze(int freeze)
+{
+ qoriq_pm_ops->freeze_time_base(freeze);
+}
+#else
static void mpc85xx_timebase_freeze(int freeze)
{
uint32_t mask;
@@ -58,6 +70,7 @@ static void mpc85xx_timebase_freeze(int freeze)
in_be32(&guts->devdisr);
}
+#endif
static void mpc85xx_give_timebase(void)
{
@@ -125,6 +138,34 @@ static void mpc85xx_take_timebase(void)
}
#ifdef CONFIG_HOTPLUG_CPU
+#ifdef CONFIG_PPC_E500MC
+static void qoriq_cpu_die(void)
+{
+ unsigned int cpu = smp_processor_id();
+
+ local_irq_disable();
+#ifdef CONFIG_PPC64
+ __hard_irq_disable();
+#endif
+ idle_task_exit();
+
+ if (qoriq_pm_ops->irq_mask)
+ qoriq_pm_ops->irq_mask(cpu);
+
+ mtspr(SPRN_TCR, 0);
+ mtspr(SPRN_TSR, mfspr(SPRN_TSR));
+
+ generic_set_cpu_dead(cpu);
+
+ if (cur_cpu_spec && cur_cpu_spec->cpu_flush_caches)
+ cur_cpu_spec->cpu_flush_caches();
+
+ qoriq_pm_ops->cpu_enter_state(cpu, qoriq_cpu_die_state);
+
+ while (1)
+ ;
+}
+#else
static void smp_85xx_mach_cpu_die(void)
{
unsigned int cpu = smp_processor_id();
@@ -155,6 +196,7 @@ static void smp_85xx_mach_cpu_die(void)
;
}
#endif
+#endif
static inline void flush_spin_table(void *spin_table)
{
@@ -208,11 +250,8 @@ static int smp_85xx_kick_cpu(int nr)
spin_table = phys_to_virt(*cpu_rel_addr);
local_irq_save(flags);
-#ifdef CONFIG_PPC32
-#ifdef CONFIG_HOTPLUG_CPU
- /* Corresponding to generic_set_cpu_dead() */
- generic_set_cpu_up(nr);
+#ifdef CONFIG_HOTPLUG_CPU
if (system_state == SYSTEM_RUNNING) {
/*
* To keep it compatible with old boot program which uses
@@ -225,6 +264,12 @@ static int smp_85xx_kick_cpu(int nr)
out_be32(&spin_table->addr_l, 0);
flush_spin_table(spin_table);
+#ifdef CONFIG_PPC_E500MC
+ /* Due to an erratum, wake the core before reset. */
+ if (qoriq_pm_ops && qoriq_pm_ops->cpu_exit_state)
+ qoriq_pm_ops->cpu_exit_state(nr, qoriq_cpu_die_state);
+#endif
+
/*
* We don't set the BPTR register here since it already points
* to the boot page properly.
@@ -247,13 +292,30 @@ static int smp_85xx_kick_cpu(int nr)
/* clear the acknowledge status */
__secondary_hold_acknowledge = -1;
+
+#ifdef CONFIG_PPC_E500MC
+ if (qoriq_pm_ops->irq_unmask)
+ qoriq_pm_ops->irq_unmask(nr);
+#endif
}
+
+ /* Corresponding to generic_set_cpu_dead() */
+ generic_set_cpu_up(nr);
#endif
+
flush_spin_table(spin_table);
out_be32(&spin_table->pir, hw_cpu);
+#ifdef CONFIG_PPC32
out_be32(&spin_table->addr_l, __pa(__early_start));
+#else
+ out_be32(&spin_table->addr_h,
+ __pa(*(u64 *)generic_secondary_smp_init) >> 32);
+ out_be32(&spin_table->addr_l,
+ __pa(*(u64 *)generic_secondary_smp_init) & 0xffffffff);
+#endif
flush_spin_table(spin_table);
+#ifdef CONFIG_PPC32
/* Wait a bit for the CPU to ack. */
if (!spin_event_timeout(__secondary_hold_acknowledge == hw_cpu,
10000, 100)) {
@@ -262,17 +324,10 @@ static int smp_85xx_kick_cpu(int nr)
ret = -ENOENT;
goto out;
}
-out:
#else
smp_generic_kick_cpu(nr);
-
- flush_spin_table(spin_table);
- out_be32(&spin_table->pir, hw_cpu);
- out_be64((u64 *)(&spin_table->addr_h),
- __pa((u64)*((unsigned long long *)generic_secondary_smp_init)));
- flush_spin_table(spin_table);
#endif
-
+out:
local_irq_restore(flags);
if (ioremappable)
@@ -445,13 +500,18 @@ void __init mpc85xx_smp_init(void)
__func__);
return;
}
- smp_85xx_ops.give_timebase = mpc85xx_give_timebase;
- smp_85xx_ops.take_timebase = mpc85xx_take_timebase;
-#ifdef CONFIG_HOTPLUG_CPU
- ppc_md.cpu_die = smp_85xx_mach_cpu_die;
-#endif
}
+ smp_85xx_ops.give_timebase = mpc85xx_give_timebase;
+ smp_85xx_ops.take_timebase = mpc85xx_take_timebase;
+
+#ifdef CONFIG_HOTPLUG_CPU
+#ifdef CONFIG_PPC_E500MC
+ ppc_md.cpu_die = qoriq_cpu_die;
+#else
+ ppc_md.cpu_die = smp_85xx_mach_cpu_die;
+#endif
+#endif
smp_ops = &smp_85xx_ops;
#ifdef CONFIG_KEXEC
--
1.7.3
More information about the Linuxppc-dev
mailing list