Blackfin arch: add supporting for double fault debug handling
Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
diff --git a/arch/blackfin/kernel/setup.c b/arch/blackfin/kernel/setup.c
index 7a82d10..8e639dc 100644
--- a/arch/blackfin/kernel/setup.c
+++ b/arch/blackfin/kernel/setup.c
@@ -52,7 +52,8 @@
#endif
char __initdata command_line[COMMAND_LINE_SIZE];
-unsigned int __initdata *__retx;
+void __initdata *init_retx, *init_saved_retx, *init_saved_seqstat,
+ *init_saved_icplb_fault_addr, *init_saved_dcplb_fault_addr;
/* boot memmap, for parsing "memmap=" */
#define BFIN_MEMMAP_MAX 128 /* number of entries in bfin_memmap */
@@ -782,16 +783,25 @@
_bfin_swrst = bfin_read_SWRST();
- /* If we double fault, reset the system - otherwise we hang forever */
- bfin_write_SWRST(DOUBLE_FAULT);
+#ifdef CONFIG_DEBUG_DOUBLEFAULT_PRINT
+ bfin_write_SWRST(_bfin_swrst & ~DOUBLE_FAULT);
+#endif
+#ifdef CONFIG_DEBUG_DOUBLEFAULT_RESET
+ bfin_write_SWRST(_bfin_swrst | DOUBLE_FAULT);
+#endif
- if (_bfin_swrst & RESET_DOUBLE)
- /*
- * don't decode the address, since you don't know if this
- * kernel's symbol map is the same as the crashing kernel
- */
- printk(KERN_INFO "Recovering from Double Fault event at %pF\n", __retx);
- else if (_bfin_swrst & RESET_WDOG)
+ if (_bfin_swrst & RESET_DOUBLE) {
+ printk(KERN_EMERG "Recovering from DOUBLE FAULT event\n");
+#ifdef CONFIG_DEBUG_DOUBLEFAULT
+ /* We assume the crashing kernel, and the current symbol table match */
+ printk(KERN_EMERG " While handling exception (EXCAUSE = 0x%x) at %pF\n",
+ (int)init_saved_seqstat & SEQSTAT_EXCAUSE, init_saved_retx);
+ printk(KERN_NOTICE " DCPLB_FAULT_ADDR: %pF\n", init_saved_dcplb_fault_addr);
+ printk(KERN_NOTICE " ICPLB_FAULT_ADDR: %pF\n", init_saved_icplb_fault_addr);
+#endif
+ printk(KERN_NOTICE " The instruction at %pF caused a double exception\n",
+ init_retx);
+ } else if (_bfin_swrst & RESET_WDOG)
printk(KERN_INFO "Recovering from Watchdog event\n");
else if (_bfin_swrst & RESET_SOFTWARE)
printk(KERN_NOTICE "Reset caused by Software reset\n");