From mboxrd@z Thu Jan 1 00:00:00 1970 From: Magnus Damm Date: Wed, 09 May 2012 07:24:59 +0000 Subject: [PATCH] mach-shmobile: Invalidate caches when booting secondary cores Message-Id: <20120509072459.20583.11420.sendpatchset@w520> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-sh@vger.kernel.org From: Magnus Damm 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 --- This should really be moved into a common location. Feel free to point me in the right direction and I will be happy to submit a patch that unifies the code. Tested on EMEV2. arch/arm/mach-shmobile/headsmp.S | 57 +++++++++++++++++++++++++++++++++++++- 1 file changed, 56 insertions(+), 1 deletion(-) --- 0001/arch/arm/mach-shmobile/headsmp.S +++ work/arch/arm/mach-shmobile/headsmp.S 2012-05-09 16:13:07.000000000 +0900 @@ -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<