The V bit of the c1 register of CP15 should not be cleared on DA850 SoCs since they have no valid memory at 0x00000000. This patch introduces a configuration option CONFIG_SYS_EXCEPTION_VECTORS_HIGH that allows setting the correct value for the V bit.
Signed-off-by: Christian Riesch christian.riesch@omicron.at Reported-by: Sughosh Ganu urwithsughosh@gmail.com Cc: Albert Aribaud albert.u.boot@aribaud.net Cc: Tom Rini trini@ti.com Cc: Sughosh Ganu urwithsughosh@gmail.com Cc: Heiko Schocher hs@denx.de --- README | 6 ++++++ arch/arm/cpu/arm926ejs/start.S | 7 ++++++- include/configs/da850evm.h | 1 + include/configs/enbw_cmc.h | 1 + include/configs/hawkboard.h | 1 + 5 files changed, 15 insertions(+), 1 deletions(-)
diff --git a/README b/README index 9d713e8..c5b0941 100644 --- a/README +++ b/README @@ -420,6 +420,12 @@ The following options need to be configured: XWAY SoCs for booting from NOR flash. The U-Boot image needs to be swapped if a flash programmer is used.
+- ARM options: + CONFIG_SYS_EXCEPTION_VECTORS_HIGH + + Select high exception vectors of the ARM core, e.g., do not + clear the V bit of the c1 register of CP15. + - Linux Kernel Interface: CONFIG_CLOCKS_IN_MHZ
diff --git a/arch/arm/cpu/arm926ejs/start.S b/arch/arm/cpu/arm926ejs/start.S index b39ed8a..525c112 100644 --- a/arch/arm/cpu/arm926ejs/start.S +++ b/arch/arm/cpu/arm926ejs/start.S @@ -372,8 +372,13 @@ flush_dcache: * disable MMU and D cache, and enable I cache */ mrc p15, 0, r0, c1, c0, 0 - bic r0, r0, #0x00002300 /* clear bits 13, 9:8 (--V- --RS) */ + bic r0, r0, #0x00000300 /* clear bits 9:8 (---- --RS) */ bic r0, r0, #0x00000087 /* clear bits 7, 2:0 (B--- -CAM) */ +#ifdef CONFIG_SYS_EXCEPTION_VECTORS_HIGH + orr r0, r0, #0x00002000 /* set bit 13 (--V- ----) */ +#else + bic r0, r0, #0x00002000 /* clear bit 13 (--V- ----) */ +#endif orr r0, r0, #0x00000002 /* set bit 2 (A) Align */ orr r0, r0, #0x00001000 /* set bit 12 (I) I-Cache */ mcr p15, 0, r0, c1, c0, 0 diff --git a/include/configs/da850evm.h b/include/configs/da850evm.h index f15a0a6..85016df 100644 --- a/include/configs/da850evm.h +++ b/include/configs/da850evm.h @@ -37,6 +37,7 @@ #define CONFIG_ARM926EJS /* arm926ejs CPU core */ #define CONFIG_SOC_DA8XX /* TI DA8xx SoC */ #define CONFIG_SOC_DA850 /* TI DA850 SoC */ +#define CONFIG_SYS_EXCEPTION_VECTORS_HIGH #define CONFIG_SYS_CLK_FREQ clk_get(DAVINCI_ARM_CLKID) #define CONFIG_SYS_OSCIN_FREQ 24000000 #define CONFIG_SYS_TIMERBASE DAVINCI_TIMER0_BASE diff --git a/include/configs/enbw_cmc.h b/include/configs/enbw_cmc.h index 21cf647..0c9ab4c 100644 --- a/include/configs/enbw_cmc.h +++ b/include/configs/enbw_cmc.h @@ -40,6 +40,7 @@ #define CONFIG_ARM926EJS /* arm926ejs CPU core */ #define CONFIG_SOC_DA8XX /* TI DA8xx SoC */ #define CONFIG_SOC_DA850 /* TI DA850 SoC */ +#define CONFIG_SYS_EXCEPTION_VECTORS_HIGH #define CONFIG_SYS_CLK_FREQ clk_get(DAVINCI_ARM_CLKID) #define CONFIG_SYS_OSCIN_FREQ 24000000 #define CONFIG_SYS_TIMERBASE DAVINCI_TIMER0_BASE diff --git a/include/configs/hawkboard.h b/include/configs/hawkboard.h index 12acb27..ce78d3c 100644 --- a/include/configs/hawkboard.h +++ b/include/configs/hawkboard.h @@ -35,6 +35,7 @@ #define CONFIG_ARM926EJS /* arm926ejs CPU core */ #define CONFIG_SOC_DA8XX /* TI DA8xx SoC */ #define CONFIG_SOC_DA850 /* TI DA850 SoC */ +#define CONFIG_SYS_EXCEPTION_VECTORS_HIGH #define CONFIG_SYS_CLK_FREQ clk_get(DAVINCI_ARM_CLKID) #define CONFIG_SYS_OSCIN_FREQ 24000000 #define CONFIG_SYS_TIMERBASE DAVINCI_TIMER0_BASE