From: Nitin Garg <[email protected]>

A short loop including a DMB instruction might cause a denial of
service on another processor which executes a CP15 broadcast operation.
Exists on r1, r2, r3, r4 revisions.

Signed-off-by: Nitin Garg <[email protected]>
---
 README                     |    1 +
 arch/arm/cpu/armv7/start.S |    5 +++++
 2 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/README b/README
index 7cb7c4f..a496c65 100644
--- a/README
+++ b/README
@@ -566,6 +566,7 @@ The following options need to be configured:
                CONFIG_ARM_ERRATA_742230
                CONFIG_ARM_ERRATA_743622
                CONFIG_ARM_ERRATA_751472
+               CONFIG_ARM_ERRATA_794072
 
                If set, the workarounds for these ARM errata are applied early
                during U-Boot startup. Note that these options force the
diff --git a/arch/arm/cpu/armv7/start.S b/arch/arm/cpu/armv7/start.S
index ac1e55a..b87a378 100644
--- a/arch/arm/cpu/armv7/start.S
+++ b/arch/arm/cpu/armv7/start.S
@@ -222,6 +222,11 @@ ENTRY(cpu_init_cp15)
        orr     r0, r0, #1 << 11        @ set bit #11
        mcr     p15, 0, r0, c15, c0, 1  @ write diagnostic register
 #endif
+#ifdef CONFIG_ARM_ERRATA_794072
+       mrc     p15, 0, r0, c15, c0, 1  @ read diagnostic register
+       orr     r0, r0, #1 << 4         @ set bit #4
+       mcr     p15, 0, r0, c15, c0, 1  @ write diagnostic register
+#endif
 
        mov     pc, lr                  @ back to my caller
 ENDPROC(cpu_init_cp15)
-- 
1.7.4.1


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