powerpc: Unify the 32 and 64 bit idle loops
This unifies the 32-bit (ARCH=ppc and ARCH=powerpc) and 64-bit idle
loops. It brings over the concept of having a ppc_md.power_save
function from 32-bit to ARCH=powerpc, which lets us get rid of
native_idle(). With this we will also be able to simplify the idle
handling for pSeries and cell.
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index 80e9fe2..f2c47e9 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -12,12 +12,12 @@
obj-y := semaphore.o cputable.o ptrace.o syscalls.o \
irq.o align.o signal_32.o pmc.o vdso.o \
- init_task.o process.o systbl.o
+ init_task.o process.o systbl.o idle.o
obj-y += vdso32/
obj-$(CONFIG_PPC64) += setup_64.o binfmt_elf32.o sys_ppc32.o \
signal_64.o ptrace32.o \
paca.o cpu_setup_power4.o \
- firmware.o sysfs.o idle_64.o
+ firmware.o sysfs.o
obj-$(CONFIG_PPC64) += vdso64/
obj-$(CONFIG_ALTIVEC) += vecemu.o vector.o
obj-$(CONFIG_POWER4) += idle_power4.o
@@ -34,6 +34,7 @@
obj-$(CONFIG_GENERIC_TBSYNC) += smp-tbsync.o
obj64-$(CONFIG_PPC_MULTIPLATFORM) += nvram_64.o
obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
+obj-$(CONFIG_6xx) += idle_6xx.o
ifeq ($(CONFIG_PPC_MERGE),y)
@@ -51,7 +52,6 @@
obj-$(CONFIG_PPC_MULTIPLATFORM) += prom_init.o
obj-$(CONFIG_MODULES) += ppc_ksyms.o
obj-$(CONFIG_BOOTX_TEXT) += btext.o
-obj-$(CONFIG_6xx) += idle_6xx.o
obj-$(CONFIG_SMP) += smp.o
obj-$(CONFIG_KPROBES) += kprobes.o
obj-$(CONFIG_PPC_UDBG_16550) += legacy_serial.o udbg_16550.o
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 4827ca1..b3a9794 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -135,10 +135,10 @@
mfspr r11,SPRN_HID0
mtcr r11
BEGIN_FTR_SECTION
- bt- 8,power_save_6xx_restore /* Check DOZE */
+ bt- 8,4f /* Check DOZE */
END_FTR_SECTION_IFSET(CPU_FTR_CAN_DOZE)
BEGIN_FTR_SECTION
- bt- 9,power_save_6xx_restore /* Check NAP */
+ bt- 9,4f /* Check NAP */
END_FTR_SECTION_IFSET(CPU_FTR_CAN_NAP)
#endif /* CONFIG_6xx */
.globl transfer_to_handler_cont
@@ -157,6 +157,10 @@
SYNC
RFI /* jump to handler, enable MMU */
+#ifdef CONFIG_6xx
+4: b power_save_6xx_restore
+#endif
+
/*
* On kernel stack overflow, load up an initial stack pointer
* and call StackOverflow(regs), which should not return.
diff --git a/arch/powerpc/kernel/idle_64.c b/arch/powerpc/kernel/idle.c
similarity index 64%
rename from arch/powerpc/kernel/idle_64.c
rename to arch/powerpc/kernel/idle.c
index b879d30..e9f321d 100644
--- a/arch/powerpc/kernel/idle_64.c
+++ b/arch/powerpc/kernel/idle.c
@@ -2,13 +2,17 @@
* Idle daemon for PowerPC. Idle daemon will handle any action
* that needs to be taken when the system becomes idle.
*
- * Originally Written by Cort Dougan (cort@cs.nmt.edu)
+ * Originally written by Cort Dougan (cort@cs.nmt.edu).
+ * Subsequent 32-bit hacking by Tom Rini, Armin Kuster,
+ * Paul Mackerras and others.
*
* iSeries supported added by Mike Corrigan <mikejc@us.ibm.com>
*
* Additional shared processor, SMT, and firmware support
* Copyright (c) 2003 Dave Engebretsen <engebret@us.ibm.com>
*
+ * 32-bit and 64-bit versions merged by Paul Mackerras <paulus@samba.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
@@ -29,18 +33,43 @@
#include <asm/machdep.h>
#include <asm/smp.h>
-extern void power4_idle(void);
+#ifdef CONFIG_HOTPLUG_CPU
+#define cpu_should_die() (cpu_is_offline(smp_processor_id()) && \
+ system_state == SYSTEM_RUNNING)
+#else
+#define cpu_should_die() 0
+#endif
-void default_idle(void)
+/*
+ * The body of the idle task.
+ */
+void cpu_idle(void)
{
- unsigned int cpu = smp_processor_id();
+ if (ppc_md.idle_loop)
+ ppc_md.idle_loop(); /* doesn't return */
+
set_thread_flag(TIF_POLLING_NRFLAG);
-
while (1) {
- if (!need_resched()) {
- while (!need_resched() && !cpu_is_offline(cpu)) {
- ppc64_runlatch_off();
+ ppc64_runlatch_off();
+ while (!need_resched() && !cpu_should_die()) {
+ if (ppc_md.power_save) {
+ clear_thread_flag(TIF_POLLING_NRFLAG);
+ /*
+ * smp_mb is so clearing of TIF_POLLING_NRFLAG
+ * is ordered w.r.t. need_resched() test.
+ */
+ smp_mb();
+ local_irq_disable();
+
+ /* check again after disabling irqs */
+ if (!need_resched() && !cpu_should_die())
+ ppc_md.power_save();
+
+ local_irq_enable();
+ set_thread_flag(TIF_POLLING_NRFLAG);
+
+ } else {
/*
* Go into low thread priority and possibly
* low power mode.
@@ -48,46 +77,18 @@
HMT_low();
HMT_very_low();
}
-
- HMT_medium();
}
+ HMT_medium();
ppc64_runlatch_on();
+ if (cpu_should_die())
+ cpu_die();
preempt_enable_no_resched();
schedule();
preempt_disable();
- if (cpu_is_offline(cpu) && system_state == SYSTEM_RUNNING)
- cpu_die();
}
}
-void native_idle(void)
-{
- while (1) {
- ppc64_runlatch_off();
-
- if (!need_resched())
- power4_idle();
-
- if (need_resched()) {
- ppc64_runlatch_on();
- preempt_enable_no_resched();
- schedule();
- preempt_disable();
- }
-
- if (cpu_is_offline(smp_processor_id()) &&
- system_state == SYSTEM_RUNNING)
- cpu_die();
- }
-}
-
-void cpu_idle(void)
-{
- BUG_ON(NULL == ppc_md.idle_loop);
- ppc_md.idle_loop();
-}
-
int powersave_nap;
#ifdef CONFIG_SYSCTL
diff --git a/arch/powerpc/kernel/idle_6xx.S b/arch/powerpc/kernel/idle_6xx.S
index 444fdcc..1647ea3 100644
--- a/arch/powerpc/kernel/idle_6xx.S
+++ b/arch/powerpc/kernel/idle_6xx.S
@@ -87,19 +87,6 @@
cmpwi 0,r3,0
beqlr
- /* Clear MSR:EE */
- mfmsr r7
- rlwinm r0,r7,0,17,15
- mtmsr r0
-
- /* Check current_thread_info()->flags */
- rlwinm r4,r1,0,0,18
- lwz r4,TI_FLAGS(r4)
- andi. r0,r4,_TIF_NEED_RESCHED
- beq 1f
- mtmsr r7 /* out of line this ? */
- blr
-1:
/* Some pre-nap cleanups needed on some CPUs */
andis. r0,r3,HID0_NAP@h
beq 2f
@@ -220,8 +207,6 @@
_GLOBAL(nap_save_hid1)
.space 4*NR_CPUS
-_GLOBAL(powersave_nap)
- .long 0
_GLOBAL(powersave_lowspeed)
.long 0
diff --git a/arch/powerpc/kernel/idle_power4.S b/arch/powerpc/kernel/idle_power4.S
index c16b4af..692cf2e 100644
--- a/arch/powerpc/kernel/idle_power4.S
+++ b/arch/powerpc/kernel/idle_power4.S
@@ -49,21 +49,6 @@
cmpwi 0,r4,0
beqlr
- /* Clear MSR:EE */
- mfmsr r7
- li r4,0
- ori r4,r4,MSR_EE
- andc r0,r7,r4
- mtmsrd r0
-
- /* Check current_thread_info()->flags */
- clrrdi r4,r1,THREAD_SHIFT
- ld r4,TI_FLAGS(r4)
- andi. r0,r4,_TIF_NEED_RESCHED
- beq 1f
- mtmsrd r7 /* out of line this ? */
- blr
-1:
/* Go to NAP now */
BEGIN_FTR_SECTION
DSSALL
diff --git a/arch/powerpc/kernel/setup_32.c b/arch/powerpc/kernel/setup_32.c
index 676f894..e39f830 100644
--- a/arch/powerpc/kernel/setup_32.c
+++ b/arch/powerpc/kernel/setup_32.c
@@ -53,9 +53,6 @@
extern void platform_init(void);
extern void bootx_init(unsigned long r4, unsigned long phys);
-extern void ppc6xx_idle(void);
-extern void power4_idle(void);
-
boot_infos_t *boot_infos;
struct ide_machdep_calls ppc_ide_md;
@@ -194,7 +191,9 @@
platform_init();
#ifdef CONFIG_6xx
- ppc_md.power_save = ppc6xx_idle;
+ if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
+ cpu_has_feature(CPU_FTR_CAN_NAP))
+ ppc_md.power_save = ppc6xx_idle;
#endif
if (ppc_md.progress)
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 6c9b093..5b63a86 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -607,12 +607,6 @@
ppc_md.setup_arch();
- /* Use the default idle loop if the platform hasn't provided one. */
- if (NULL == ppc_md.idle_loop) {
- ppc_md.idle_loop = default_idle;
- printk(KERN_INFO "Using default idle loop\n");
- }
-
paging_init();
ppc64_boot_msg(0x15, "Setup Done");
}
diff --git a/arch/powerpc/platforms/maple/setup.c b/arch/powerpc/platforms/maple/setup.c
index ec5c1e1..137d606 100644
--- a/arch/powerpc/platforms/maple/setup.c
+++ b/arch/powerpc/platforms/maple/setup.c
@@ -290,7 +290,7 @@
.get_rtc_time = maple_get_rtc_time,
.calibrate_decr = generic_calibrate_decr,
.progress = maple_progress,
- .idle_loop = native_idle,
+ .power_save = power4_idle,
#ifdef CONFIG_KEXEC
.machine_kexec = default_machine_kexec,
.machine_kexec_prepare = default_machine_kexec_prepare,
diff --git a/arch/powerpc/platforms/powermac/setup.c b/arch/powerpc/platforms/powermac/setup.c
index 385aab9..c2696d0 100644
--- a/arch/powerpc/platforms/powermac/setup.c
+++ b/arch/powerpc/platforms/powermac/setup.c
@@ -733,7 +733,7 @@
.progress = udbg_progress,
#ifdef CONFIG_PPC64
.pci_probe_mode = pmac_pci_probe_mode,
- .idle_loop = native_idle,
+ .power_save = power4_idle,
.enable_pmcs = power4_enable_pmcs,
#ifdef CONFIG_KEXEC
.machine_kexec = default_machine_kexec,