From: Andreas Bießmann Date: Wed, 9 Jun 2010 12:13:45 +0000 (+0200) Subject: avr32: disable branch folding X-Git-Tag: v2010.09-rc1~107^2~5 X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=eb70d05d740c1d82474d2c31242a4e995584de24;p=oweals%2Fu-boot.git avr32: disable branch folding Due to a hardware bug mentioned in latest AP7000 datasheet errata (revision M from 09.09) branch folding is unreliable. This patch disables CPUCR.FE bitfield as stated in datasheet. Signed-off-by: Andreas Bießmann --- diff --git a/arch/avr32/cpu/start.S b/arch/avr32/cpu/start.S index d37a46eb18..99c9e06cb8 100644 --- a/arch/avr32/cpu/start.S +++ b/arch/avr32/cpu/start.S @@ -27,9 +27,10 @@ #define SYSREG_MMUCR_S_OFFSET 4 #define SR_INIT (SYSREG_BIT(GM) | SYSREG_BIT(EM) | SYSREG_BIT(M0)) -#define CPUCR_INIT (SYSREG_BIT(BI) | SYSREG_BIT(BE) \ - | SYSREG_BIT(FE) | SYSREG_BIT(RE) \ - | SYSREG_BIT(IBE) | SYSREG_BIT(IEE)) +/* due to errata (unreliable branch folding) clear FE bit explicitly */ +#define CPUCR_INIT ((SYSREG_BIT(BI) | SYSREG_BIT(BE) \ + | SYSREG_BIT(RE) | SYSREG_BIT(IBE) \ + | SYSREG_BIT(IEE)) & ~SYSREG_BIT(FE)) /* * To save some space, we use the same entry point for