iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

powerpc/powernv: Make it possible to skip the IRQHAPPENED check in power7_nap()

Browse Source 
To support split core we need to be able to force all secondaries into
nap, so the core can detect they are idle and do an unsplit.

Currently power7_nap() will return without napping if there is an irq
pending. We want to ignore the pending irq and nap anyway, we will deal
with the interrupt later.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Michael Ellerman 2014-05-23 18:15:26 +10:00 committed by Benjamin Herrenschmidt
parent 441c19c8a2
commit 8d6f7c5aa3
3 changed files with 11 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/powerpc/include/asm/processor.h
View File

@ -449,7 +449,7 @@ extern unsigned long cpuidle_disable;
enum idle_boot_override {IDLE_NO_OVERRIDE = 0, IDLE_POWERSAVE_OFF};
extern int powersave_nap; /* set if nap mode can be used in idle loop */
extern void power7_nap(void);
extern void power7_nap(int check_irq);
extern void power7_sleep(void);
extern void flush_instruction_cache(void);
extern void hard_reset_now(void);

9
arch/powerpc/kernel/idle_power7.S
View File

@ -39,6 +39,10 @@
* Pass requested state in r3:
* 0 - nap
* 1 - sleep
*
* To check IRQ_HAPPENED in r4
* 0 - don't check
* 1 - check
*/
_GLOBAL(power7_powersave_common)
/* Use r3 to pass state nap/sleep/winkle */
@ -71,6 +75,8 @@ _GLOBAL(power7_powersave_common)
lbz r0,PACAIRQHAPPENED(r13)
cmpwi cr0,r0,0
beq 1f
cmpwi cr0,r4,0
beq 1f
addi r1,r1,INT_FRAME_SIZE
ld r0,16(r1)
mtlr r0
@ -114,15 +120,18 @@ _GLOBAL(power7_idle)
lwz r4,ADDROFF(powersave_nap)(r3)
cmpwi 0,r4,0
beqlr
li r3, 1
/* fall through */
_GLOBAL(power7_nap)
mr r4,r3
li r3,0
b power7_powersave_common
/* No return */
_GLOBAL(power7_sleep)
li r3,1
li r4,0
b power7_powersave_common
/* No return */

2
arch/powerpc/platforms/powernv/smp.c
View File

@ -159,7 +159,7 @@ static void pnv_smp_cpu_kill_self(void)
mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) & ~(u64)LPCR_PECE1);
while (!generic_check_cpu_restart(cpu)) {
ppc64_runlatch_off();
power7_nap();
power7_nap(1);
ppc64_runlatch_on();
if (!generic_check_cpu_restart(cpu)) {
DBG("CPU%d Unexpected exit while offline !\n", cpu);