ARM / mach-shmobile: Invalidate caches when booting secondary cores

Make sure L1 caches are invalidated when booting secondary
cores. Needed to boot all mach-shmobile SMP systems that
are using Cortex-A9 including sh73a0, r8a7779 and EMEV2.

Thanks to imx and tegra guys for actual code.

Signed-off-by: Magnus Damm <damm@opensource.se>
Tested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
This commit is contained in:
Magnus Damm 2012-05-09 16:24:59 +09:00 committed by Rafael J. Wysocki
parent d6720003c3
commit e994d5eb7c

View File

@ -16,6 +16,59 @@
__CPUINIT
/* Cache invalidation nicked from arch/arm/mach-imx/head-v7.S, thanks!
*
* The secondary kernel init calls v7_flush_dcache_all before it enables
* the L1; however, the L1 comes out of reset in an undefined state, so
* the clean + invalidate performed by v7_flush_dcache_all causes a bunch
* of cache lines with uninitialized data and uninitialized tags to get
* written out to memory, which does really unpleasant things to the main
* processor. We fix this by performing an invalidate, rather than a
* clean + invalidate, before jumping into the kernel.
*
* This funciton is cloned from arch/arm/mach-tegra/headsmp.S, and needs
* to be called for both secondary cores startup and primary core resume
* procedures. Ideally, it should be moved into arch/arm/mm/cache-v7.S.
*/
ENTRY(v7_invalidate_l1)
mov r0, #0
mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
mcr p15, 2, r0, c0, c0, 0
mrc p15, 1, r0, c0, c0, 0
ldr r1, =0x7fff
and r2, r1, r0, lsr #13
ldr r1, =0x3ff
and r3, r1, r0, lsr #3 @ NumWays - 1
add r2, r2, #1 @ NumSets
and r0, r0, #0x7
add r0, r0, #4 @ SetShift
clz r1, r3 @ WayShift
add r4, r3, #1 @ NumWays
1: sub r2, r2, #1 @ NumSets--
mov r3, r4 @ Temp = NumWays
2: subs r3, r3, #1 @ Temp--
mov r5, r3, lsl r1
mov r6, r2, lsl r0
orr r5, r5, r6 @ Reg = (Temp<<WayShift)|(NumSets<<SetShift)
mcr p15, 0, r5, c7, c6, 2
bgt 2b
cmp r2, #0
bgt 1b
dsb
isb
mov pc, lr
ENDPROC(v7_invalidate_l1)
ENTRY(shmobile_invalidate_start)
bl v7_invalidate_l1
b secondary_startup
ENDPROC(shmobile_invalidate_start)
/*
* Reset vector for secondary CPUs.
* This will be mapped at address 0 by SBAR register.
@ -24,4 +77,5 @@
.align 12
ENTRY(shmobile_secondary_vector)
ldr pc, 1f
1: .long secondary_startup - PAGE_OFFSET + PLAT_PHYS_OFFSET
1: .long shmobile_invalidate_start - PAGE_OFFSET + PLAT_PHYS_OFFSET
ENDPROC(shmobile_secondary_vector)