From 9c46e71af2b03ccd721c56b1dc906ead702d6fb5 Mon Sep 17 00:00:00 2001 From: Mike Frysinger Date: Mon, 24 Aug 2009 20:48:04 -0400 Subject: 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 --- cpu/blackfin/interrupt.S | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'cpu') diff --git a/cpu/blackfin/interrupt.S b/cpu/blackfin/interrupt.S index dd2cc53..71e0fc6 100644 --- a/cpu/blackfin/interrupt.S +++ b/cpu/blackfin/interrupt.S @@ -5,6 +5,7 @@ * Licensed under the GPL-2 or later. */ +#include #include #include @@ -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) -- cgit v1.1