u-boot/cpu/blackfin/interrupt.S
Mike Frysinger 9c46e71af2 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>
2009-09-02 05:58:38 -04:00

38 lines
810 B
ArmAsm

/*
* interrupt.S - trampoline default exceptions/interrupts to C handlers
*
* Copyright (c) 2005-2007 Analog Devices Inc.
* Licensed under the GPL-2 or later.
*/
#include <config.h>
#include <asm/blackfin.h>
#include <asm/entry.h>
.text
/* 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)
/* default entry point for interrupts */
ENTRY(_evt_default)
SAVE_ALL_SYS
r0 = sp; /* stack frame pt_regs pointer argument ==> r0 */
sp += -12;
call _bfin_panic;
sp += 12;
RESTORE_ALL_SYS
rti;
ENDPROC(_evt_default)