From: Nitin Garg Date: Wed, 2 Apr 2014 13:55:01 +0000 (-0500) Subject: ARM: Add workaround for Cortex-A9 errata 794072 X-Git-Tag: v2014.04~18^2~2 X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=f71cbfe3ca5d;p=oweals%2Fu-boot.git ARM: Add workaround for Cortex-A9 errata 794072 A short loop including a DMB instruction might cause a denial of service on another processor which executes a CP15 broadcast operation. Exists on r1, r2, r3, r4 revisions. Signed-off-by: Nitin Garg Acked-by: Dirk Behme --- diff --git a/README b/README index 216f0c70aa..00127a75ef 100644 --- a/README +++ b/README @@ -566,6 +566,7 @@ The following options need to be configured: CONFIG_ARM_ERRATA_742230 CONFIG_ARM_ERRATA_743622 CONFIG_ARM_ERRATA_751472 + CONFIG_ARM_ERRATA_794072 If set, the workarounds for these ARM errata are applied early during U-Boot startup. Note that these options force the diff --git a/arch/arm/cpu/armv7/start.S b/arch/arm/cpu/armv7/start.S index ac1e55a708..f3830c8471 100644 --- a/arch/arm/cpu/armv7/start.S +++ b/arch/arm/cpu/armv7/start.S @@ -205,7 +205,7 @@ ENTRY(cpu_init_cp15) mcr p15, 0, r0, c1, c0, 0 @ write system control register #endif -#ifdef CONFIG_ARM_ERRATA_742230 +#if (defined(CONFIG_ARM_ERRATA_742230) || defined(CONFIG_ARM_ERRATA_794072)) mrc p15, 0, r0, c15, c0, 1 @ read diagnostic register orr r0, r0, #1 << 4 @ set bit #4 mcr p15, 0, r0, c15, c0, 1 @ write diagnostic register