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powerpc: Properly handshake CPUs going out of boot spin loop

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We need to wait a bit for them to have done their CPU setup
or we might end up with translation and EE on with different
LPCR values between threads

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Benjamin Herrenschmidt
2011-03-16 14:54:35 +11:00
parent ad0693ee72
commit 9d07bc841c
5 changed files with 37 additions and 23 deletions
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18
arch/powerpc/kernel/head_64.S
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@@ -242,23 +242,31 @@ generic_secondary_common_init:
ld r23,0(r23)
ld r23,CPU_SPEC_RESTORE(r23)
cmpdi 0,r23,0
beq 4f
beq 3f
ld r23,0(r23)
mtctr r23
bctrl
3: HMT_LOW
3: LOAD_REG_ADDR(r3, boot_cpu_count) /* Decrement boot_cpu_count */
lwarx r4,0,r3
subi r4,r4,1
stwcx. r4,0,r3
bne 3b
isync
4: HMT_LOW
lbz r23,PACAPROCSTART(r13) /* Test if this processor should */
/* start. */
#ifndef CONFIG_SMP
b 3b /* Never go on non-SMP */
b 4b /* Never go on non-SMP */
#else
cmpwi 0,r23,0
beq 3b /* Loop until told to go */
beq 4b /* Loop until told to go */
sync /* order paca.run and cur_cpu_spec */
isync /* In case code patching happened */
4: /* Create a temp kernel stack for use before relocation is on. */
/* Create a temp kernel stack for use before relocation is on. */
ld r1,PACAEMERGSP(r13)
subi r1,r1,STACK_FRAME_OVERHEAD