Commit 855c551f authored by Catalin Marinas's avatar Catalin Marinas Committed by Russell King

[ARM] 5490/1: ARM errata: Processor deadlock when a false hazard is created

This patch adds a workaround for the 458693 Cortex-A8 (r2p0)
erratum. It sets the corresponding bits in the auxiliary control
register so that the PLD instruction becomes a NOP.
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 7ce236fc
......@@ -765,6 +765,19 @@ config ARM_ERRATA_430973
Note that setting specific bits in the ACTLR register may not be
available in non-secure mode.
config ARM_ERRATA_458693
bool "ARM errata: Processor deadlock when a false hazard is created"
depends on CPU_V7
help
This option enables the workaround for the 458693 Cortex-A8 (r2p0)
erratum. For very specific sequences of memory operations, it is
possible for a hazard condition intended for a cache line to instead
be incorrectly associated with a different cache line. This false
hazard might then cause a processor deadlock. The workaround enables
the L1 caching of the NEON accesses and disables the PLD instruction
in the ACTLR register. Note that setting specific bits in the ACTLR
register may not be available in non-secure mode.
endmenu
source "arch/arm/common/Kconfig"
......
......@@ -187,6 +187,12 @@ __v7_setup:
mrc p15, 0, r10, c1, c0, 1 @ read aux control register
orr r10, r10, #(1 << 6) @ set IBE to 1
mcr p15, 0, r10, c1, c0, 1 @ write aux control register
#endif
#ifdef CONFIG_ARM_ERRATA_458693
mrc p15, 0, r10, c1, c0, 1 @ read aux control register
orr r10, r10, #(1 << 5) @ set L1NEON to 1
orr r10, r10, #(1 << 9) @ set PLDNOP to 1
mcr p15, 0, r10, c1, c0, 1 @ write aux control register
#endif
mov r10, #0
#ifdef HARVARD_CACHE
......
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