Re: [U-Boot] [PATCH v2] avr32: disable branch folding
Dear =?UTF-8?q?Andreas=20Bie=C3=9Fmann?=, In message 1276085625-7785-1-git-send-email-biessm...@corscience.de you wrote: 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 biessm...@corscience.de --- Changes since v1: - fix comment arch/avr32/cpu/start.S |7 --- 1 files changed, 4 insertions(+), 3 deletions(-) Applied to next branch. Thanks. Best regards, Wolfgang Denk -- DENX Software Engineering GmbH, MD: Wolfgang Denk Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: w...@denx.de Humanity has the stars in its future, and that future is too important to be lost under the burden of juvenile folly and ignorant superstition. - Isaac Asimov ___ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
[U-Boot] [PATCH v2] 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 biessm...@corscience.de --- Changes since v1: - fix comment arch/avr32/cpu/start.S |7 --- 1 files changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/avr32/cpu/start.S b/arch/avr32/cpu/start.S index d37a46e..99c9e06 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 -- 1.7.1 ___ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
