diff options
| author | Mike Frysinger <vapier@gentoo.org> | 2009-08-24 20:48:04 -0400 |
|---|---|---|
| committer | Mike Frysinger <vapier@gentoo.org> | 2009-09-02 05:58:38 -0400 |
| commit | 9c46e71af2b03ccd721c56b1dc906ead702d6fb5 (patch) | |
| tree | 4b97879f42b15dc48b15776d1ff672b090731de3 | |
| parent | 69a25ce3578f34c8accb476f70089f3a44b78ed9 (diff) | |
Blackfin: use scratch pad for exception stack
If the memory layout pushes the stack out of the default DCPLB coverage,
the exception handler may trigger a double fault by trying to push onto
the uncovered stack. So handle the exception stack similar to the kernel
by using the top of the scratch pad SRAM.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
| -rw-r--r-- | cpu/blackfin/interrupt.S | 5 | ||||
| -rw-r--r-- | include/asm-blackfin/config.h | 4 |
2 files changed, 9 insertions, 0 deletions
diff --git a/cpu/blackfin/interrupt.S b/cpu/blackfin/interrupt.S index dd2cc5320..71e0fc670 100644 --- a/cpu/blackfin/interrupt.S +++ b/cpu/blackfin/interrupt.S @@ -5,6 +5,7 @@ * Licensed under the GPL-2 or later. */ +#include <config.h> #include <asm/blackfin.h> #include <asm/entry.h> @@ -12,12 +13,16 @@ /* default entry point for exceptions */ ENTRY(_trap) + CONFIG_BFIN_SCRATCH_REG = sp; + sp.l = LO(L1_SRAM_SCRATCH_END - 20); + sp.h = HI(L1_SRAM_SCRATCH_END - 20); SAVE_ALL_SYS r0 = sp; /* stack frame pt_regs pointer argument ==> r0 */ sp += -12; call _trap_c; sp += 12; RESTORE_ALL_SYS + sp = CONFIG_BFIN_SCRATCH_REG; rtx; ENDPROC(_trap) diff --git a/include/asm-blackfin/config.h b/include/asm-blackfin/config.h index 5739b1377..25794dd4b 100644 --- a/include/asm-blackfin/config.h +++ b/include/asm-blackfin/config.h @@ -14,6 +14,10 @@ # error CONFIG_BFIN_CPU: your board config needs to define this #endif +#ifndef CONFIG_BFIN_SCRATCH_REG +# define CONFIG_BFIN_SCRATCH_REG retn +#endif + /* Make sure the structure is properly aligned */ #if ((CONFIG_SYS_GBL_DATA_ADDR & -4) != CONFIG_SYS_GBL_DATA_ADDR) # error CONFIG_SYS_GBL_DATA_ADDR: must be 4 byte aligned |