Commit 730a8128 authored Aug 10, 2012 by Will Deacon Committed by Russell King Aug 11, 2012

ARM: 7489/1: errata: fix workaround for erratum #720789 on UP systems



Commit 5a783cbc ("ARM: 7478/1: errata: extend workaround for erratum
 #720789") added workarounds for erratum #720789 to the range TLB
invalidation functions with the observation that the erratum only
affects SMP platforms. However, when running an SMP_ON_UP kernel on a
uniprocessor platform we must take care to preserve the ASID as the
workaround is not required.

This patch ensures that we don't set the ASID to 0 when flushing the TLB
on such a system, preserving the original behaviour with the workaround
disabled.

Cc: <stable@vger.kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

parent f5f2025e

arch/arm/mm/tlb-v7.S

+3 −3

Original line number	Diff line number	Diff line
		@@ -38,10 +38,10 @@ ENTRY(v7wbi_flush_user_tlb_range)
		dsb
		mov r0, r0, lsr #PAGE_SHIFT @ align address
		mov r1, r1, lsr #PAGE_SHIFT
		#ifdef CONFIG_ARM_ERRATA_720789
		mov r3, #0
		#else
		asid r3, r3 @ mask ASID
		#ifdef CONFIG_ARM_ERRATA_720789
		ALT_SMP(W(mov) r3, #0 )
		ALT_UP(W(nop) )
		#endif
		orr r0, r3, r0, lsl #PAGE_SHIFT @ Create initial MVA
		mov r1, r1, lsl #PAGE_SHIFT

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