From 0678587fb6f517d40c461f1d43fe7a6ff430f168 Mon Sep 17 00:00:00 2001 From: Stephen Warren Date: Tue, 26 Feb 2013 12:28:27 +0000 Subject: 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 Acked-by: Simon Glass --- README | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'README') diff --git a/README b/README index d51ece946c..e45ae4a135 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 -- cgit v1.2.1