ARM: Introduce erratum workaround for 430973

430973: Stale prediction on replaced inter working branch causes
	Cortex-A8 to execute in the wrong ARM/Thumb state
Impacts: Every Cortex-A8 processors with revision lower than r2p1
Work around: Set IBE to 1

Based on ARM errata Document revision 20.0 (13 Nov 2010)

Signed-off-by: Nishanth Menon <nm@ti.com>
Tested-by: Matt Porter <mporter@konsulko.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
This commit is contained in:
Nishanth Menon 2015-03-09 17:12:01 -05:00 committed by Tom Rini
parent b45c48a7c3
commit 5902f4ce0f
2 changed files with 14 additions and 0 deletions

1
README
View File

@ -693,6 +693,7 @@ The following options need to be configured:
NOTE: The following can be machine specific errata. These
do have ability to provide rudimentary version and machine
specific checks, but expect no product checks.
CONFIG_ARM_ERRATA_430973
CONFIG_ARM_ERRATA_454179
CONFIG_ARM_ERRATA_798870

View File

@ -200,6 +200,19 @@ skip_errata_798870:
pop {r1-r5} @ Restore the cpu info - fall through
skip_errata_454179:
#endif
#ifdef CONFIG_ARM_ERRATA_430973
cmp r2, #0x21 @ Only on < r2p1
bge skip_errata_430973
mrc p15, 0, r0, c1, c0, 1 @ Read ACR
orr r0, r0, #(0x1 << 6) @ Set IBE bit
push {r1-r5} @ Save the cpu info registers
bl v7_arch_cp15_set_acr
pop {r1-r5} @ Restore the cpu info - fall through
skip_errata_430973:
#endif
mov pc, r5 @ back to my caller