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| author | Sascha Hauer <s.hauer@pengutronix.de> | 2015-02-26 13:44:50 +0100 |
|---|---|---|
| committer | Sascha Hauer <s.hauer@pengutronix.de> | 2015-02-27 13:17:31 +0100 |
| commit | b42a3e2f68f97464d60110c58ba5f5f0e4bc333b (patch) | |
| tree | bbae588bdc9fb5ba9ba7992792d6a5acd6c4ba88 /arch | |
| parent | 86759346bac4477c6b3b34bbfc47bb42c46046a1 (diff) | |
| download | barebox-b42a3e2f68f97464d60110c58ba5f5f0e4bc333b.tar.gz barebox-b42a3e2f68f97464d60110c58ba5f5f0e4bc333b.tar.xz | |
ARM: Allow to mask data aborts
Sometimes it's useful to test if a memory operation works or
aborts. This adds data_abort_mask() to ignore data aborts and
data_abort_unmask() to enable them again. This is used in the
next step for the 'md' command so that illegal addresses just
show 'xxxxxxxx' instead of crashing the system.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/cpu/exceptions.S | 22 | ||||
| -rw-r--r-- | arch/arm/cpu/interrupts.c | 17 | ||||
| -rw-r--r-- | arch/arm/include/asm/barebox.h | 4 |
3 files changed, 43 insertions, 0 deletions
diff --git a/arch/arm/cpu/exceptions.S b/arch/arm/cpu/exceptions.S index 167c8d1fe2..f17f1e11e4 100644 --- a/arch/arm/cpu/exceptions.S +++ b/arch/arm/cpu/exceptions.S @@ -88,6 +88,21 @@ movs pc, lr .endm + .macro try_data_abort + ldr r13, =arm_ignore_data_abort @ check try mode + ldr r13, [r13] + cmp r13, #0 + beq do_abort_\@ + ldr r13, =arm_data_abort_occurred + str r13, [r13] + mrs r13, spsr @ read saved CPSR + tst r13, #1<<5 @ check Thumb mode + subeq lr, #4 @ next ARM instr + subne lr, #6 @ next Thumb instr + movs pc, lr +do_abort_\@: + .endm + .macro get_irq_stack @ setup IRQ stack ldr sp, IRQ_STACK_START .endm @@ -122,6 +137,7 @@ prefetch_abort: .align 5 data_abort: + try_data_abort get_bad_stack bad_save_user_regs bl do_data_abort @@ -202,5 +218,11 @@ _fiq: .word fiq .section .data .align 4 +.global arm_ignore_data_abort +arm_ignore_data_abort: +.word arm_ignore_data_abort /* When != 0 data aborts are ignored */ +.global arm_data_abort_occurred +arm_data_abort_occurred: +.word arm_data_abort_occurred /* set != 0 by the data abort handler */ abort_stack: .space 8 diff --git a/arch/arm/cpu/interrupts.c b/arch/arm/cpu/interrupts.c index 6e60adc43a..c437af7188 100644 --- a/arch/arm/cpu/interrupts.c +++ b/arch/arm/cpu/interrupts.c @@ -23,6 +23,7 @@ */ #include <common.h> +#include <abort.h> #include <asm/ptrace.h> #include <asm/unwind.h> @@ -161,3 +162,19 @@ void do_irq (struct pt_regs *pt_regs) printf ("interrupt request\n"); do_exception(pt_regs); } + +extern volatile int arm_ignore_data_abort; +extern volatile int arm_data_abort_occurred; + +void data_abort_mask(void) +{ + arm_data_abort_occurred = 0; + arm_ignore_data_abort = 1; +} + +int data_abort_unmask(void) +{ + arm_ignore_data_abort = 0; + + return arm_data_abort_occurred != 0; +} diff --git a/arch/arm/include/asm/barebox.h b/arch/arm/include/asm/barebox.h index 2b08d68909..31a8e15630 100644 --- a/arch/arm/include/asm/barebox.h +++ b/arch/arm/include/asm/barebox.h @@ -5,4 +5,8 @@ #define ARCH_HAS_STACK_DUMP #endif +#ifdef CONFIG_ARM_EXCEPTIONS +#define ARCH_HAS_DATA_ABORT_MASK +#endif + #endif /* _BAREBOX_H_ */ |