ARM: Introduce erratum workaround for 621766

621766: Under a specific set of conditions, executing a sequence of
	NEON or vfp load instructions can cause processor deadlock
Impacts: Every Cortex-A8 processors with revision lower than r2p1
Work around: Set L1NEON 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 17:12:02 -05:00 committed by Tom Rini
parent 5902f4ce0f
commit 9b4d65f918
2 changed files with 14 additions and 0 deletions

1
README
View file

@ -695,6 +695,7 @@ The following options need to be configured:
specific checks, but expect no product checks.
CONFIG_ARM_ERRATA_430973
CONFIG_ARM_ERRATA_454179
CONFIG_ARM_ERRATA_621766
CONFIG_ARM_ERRATA_798870
- Tegra SoC options:

View file

@ -213,6 +213,19 @@ skip_errata_454179:
pop {r1-r5} @ Restore the cpu info - fall through
skip_errata_430973:
#endif
#ifdef CONFIG_ARM_ERRATA_621766
cmp r2, #0x21 @ Only on < r2p1
bge skip_errata_621766
mrc p15, 0, r0, c1, c0, 1 @ Read ACR
orr r0, r0, #(0x1 << 5) @ Set L1NEON 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_621766:
#endif
mov pc, r5 @ back to my caller