From: Dave Martin Date: Thu, 8 Dec 2011 12:41:06 +0000 (+0100) Subject: ARM: 7197/1: errata: Remove SMP dependency for erratum 751472 X-Git-Tag: firefly_0821_release~3680^2~3867^2~1 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=ba90c516bae79b5f8184d915bfce7eb280af61b1;p=firefly-linux-kernel-4.4.55.git ARM: 7197/1: errata: Remove SMP dependency for erratum 751472 Activation conditions for a workaround should not be encoded in the workaround's direct dependencies if this makes otherwise reasonable configuration choices impossible. This patches uses the SMP/UP patching facilities instead to compile out the workaround if the configuration means that it is definitely not needed. This means that configs for buggy silicon can simply select ARM_ERRATA_751472, without preventing a UP kernel from being built or duplicatiing knowledge about when to activate the workaround. This seems the correct way to do things, because the erratum is a property of the silicon, irrespective of what the kernel config happens to be. Signed-off-by: Dave Martin Signed-off-by: Russell King --- diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index d450692bc848..b259c7c644e3 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1282,7 +1282,7 @@ config ARM_ERRATA_743622 config ARM_ERRATA_751472 bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation" - depends on CPU_V7 && SMP + depends on CPU_V7 help This option enables the workaround for the 751472 Cortex-A9 (prior to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S index 2c559ac38142..e70a73731eaa 100644 --- a/arch/arm/mm/proc-v7.S +++ b/arch/arm/mm/proc-v7.S @@ -363,11 +363,13 @@ __v7_setup: orreq r10, r10, #1 << 6 @ set bit #6 mcreq p15, 0, r10, c15, c0, 1 @ write diagnostic register #endif -#ifdef CONFIG_ARM_ERRATA_751472 - cmp r6, #0x30 @ present prior to r3p0 +#if defined(CONFIG_ARM_ERRATA_751472) && defined(CONFIG_SMP) + ALT_SMP(cmp r6, #0x30) @ present prior to r3p0 + ALT_UP_B(1f) mrclt p15, 0, r10, c15, c0, 1 @ read diagnostic register orrlt r10, r10, #1 << 11 @ set bit #11 mcrlt p15, 0, r10, c15, c0, 1 @ write diagnostic register +1: #endif 3: mov r10, #0