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authorStephen Warren <swarren@nvidia.com>2013-02-26 12:28:27 +0000
committerAlbert ARIBAUD <albert.u.boot@aribaud.net>2013-03-13 22:24:11 +0100
commit0678587fb6f517d40c461f1d43fe7a6ff430f168 (patch)
treef740ba06aaa5333ba187b291e687a03054bd936f /README
parentef123c525370463254a6f8e67563fdb0b0b46412 (diff)
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ARM: implement some Cortex-A9 errata workarounds
Various errata exist in the Cortex-A9 CPU, and may be worked around by setting some bits in a CP15 diagnostic register. Add code to implement the workarounds, enabled by new CONFIG_ options. This code was taken from the Linux kernel, v3.8, arch/arm/mm/proc-v7.S, and modified to remove the logic to conditionally apply the WAR (since we know exactly which CPU we're running on given the U-Boot configuration), and use r0 instead of r10 for consistency with the rest of U-Boot's cpu_init_cp15(). Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'README')
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1 files changed, 10 insertions, 0 deletions
diff --git a/README b/README
index d51ece9..e45ae4a 100644
--- a/README
+++ b/README
@@ -485,6 +485,16 @@ The following options need to be configured:
Thumb2 this flag will result in Thumb2 code generated by
GCC.
+ CONFIG_ARM_ERRATA_742230
+ CONFIG_ARM_ERRATA_743622
+ CONFIG_ARM_ERRATA_751472
+
+ If set, the workarounds for these ARM errata are applied early
+ during U-Boot startup. Note that these options force the
+ workarounds to be applied; no CPU-type/version detection
+ exists, unlike the similar options in the Linux kernel. Do not
+ set these options unless they apply!
+
- Linux Kernel Interface:
CONFIG_CLOCKS_IN_MHZ