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 <n...@ti.com>
---
Change since V4:
        - push and pop r5 too
        - bl to handler instead of b
 README                     |    1 +
 arch/arm/cpu/armv7/start.S |   13 +++++++++++++
 2 files changed, 14 insertions(+)

diff --git a/README b/README
index 82f7e10c71d6..e7e90a08145e 100644
--- a/README
+++ b/README
@@ -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
 
 - Driver Model
diff --git a/arch/arm/cpu/armv7/start.S b/arch/arm/cpu/armv7/start.S
index a5739f392bca..9b8d3cf2595a 100644
--- a/arch/arm/cpu/armv7/start.S
+++ b/arch/arm/cpu/armv7/start.S
@@ -215,6 +215,19 @@ skip_errata_454179:
 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
 ENDPROC(cpu_init_cp15)
 
-- 
1.7.9.5

_______________________________________________
U-Boot mailing list
U-Boot@lists.denx.de
http://lists.denx.de/mailman/listinfo/u-boot

Reply via email to