Slightly more stable crash handler.

2 files changed, 20 insertions, 15 deletions

diff --git a/arch/arm/lpc17xx/handlers.c b/arch/arm/lpc17xx/handlers.c
index b3366e0..ffd01dc 100644
--- a/arch/arm/lpc17xx/handlers.c
+++ b/arch/arm/lpc17xx/handlers.c
@@ -11,24 +11,29 @@ enum FaultType {
     NMI = 2, HardFault, MemManage, BusFault, UsageFault,
 };
 
-struct fault_data_t {
-    uint32_t r4, r5, r6, r7, r8, r9, r10, r11, r0, r1, r2, r3, r12, lr, pc, xPSR;
+struct fault_data_cpu_t {
+    uint32_t r0, r1, r2, r3, r12, lr, pc, xPSR;
 };
 
-static void print_fault_data(struct fault_data_t * fault_data1, struct fault_data_t * fault_data2) {
+struct fault_data_extra_t {
+    uint32_t r4, r5, r6, r7, r8, r9, r10, r11;
+};
+
+static void print_fault_data(struct fault_data_cpu_t * fault_data_cpu, struct fault_data_extra_t * fault_data_extra) {
     // These ones are saved naturally by the CPU
-    DBGOUT("pc:   %p\r\n", fault_data1->pc);
-    DBGOUT("sp  = %p - lr  = %p - r12 = %p -xPSR = %p\r\n", fault_data1 + 1, fault_data1->lr, fault_data1->r12, fault_data1->xPSR);
-    DBGOUT("r0  = %p - r1  = %p - r2  = %p - r3  = %p\r\n", fault_data1->r0, fault_data1->r1, fault_data1->r2, fault_data1->r3);
+    DBGOUT("fd_cpu = %p - fd_extra = %p\r\n", fault_data_cpu, fault_data_extra);
+    DBGOUT("pc:   %p\r\n", fault_data_cpu->pc);
+    DBGOUT("sp  = %p - lr  = %p - r12 = %p -xPSR = %p\r\n", fault_data_cpu + 1, fault_data_cpu->lr, fault_data_cpu->r12, fault_data_cpu->xPSR);
+    DBGOUT("r0  = %p - r1  = %p - r2  = %p - r3  = %p\r\n", fault_data_cpu->r0, fault_data_cpu->r1, fault_data_cpu->r2, fault_data_cpu->r3);
     // These ones are saved by the ASM handler; hence the reason they are before in memory.
-    DBGOUT("r4  = %p - r5  = %p - r6  = %p - r7  = %p\r\n", fault_data2->r4, fault_data2->r5, fault_data2->r6, fault_data2->r7);
-    DBGOUT("r8  = %p - r9  = %p - r10 = %p - r11 = %p\r\n", fault_data2->r8, fault_data2->r9, fault_data2->r10, fault_data2->r11);
+    DBGOUT("r4  = %p - r5  = %p - r6  = %p - r7  = %p\r\n", fault_data_extra->r4, fault_data_extra->r5, fault_data_extra->r6, fault_data_extra->r7);
+    DBGOUT("r8  = %p - r9  = %p - r10 = %p - r11 = %p\r\n", fault_data_extra->r8, fault_data_extra->r9, fault_data_extra->r10, fault_data_extra->r11);
 }
 
-void general_C_handler(enum FaultType fault, struct fault_data_t * fault_data2) {
-    uintptr_t eflags = ((uintptr_t) __builtin_return_address(0)) & 15;
-    struct fault_data_t * fault_data1 = (eflags & 4 ? fault_data2 : (struct fault_data_t *) __get_MSP());
-    DBGOUT("***FAULT***\r\nType: ");
+void general_C_handler(enum FaultType fault, struct fault_data_extra_t * fault_data_extra, uintptr_t lr) {
+    uintptr_t eflags = lr & 15;
+    struct fault_data_cpu_t * fault_data_cpu = (struct fault_data_cpu_t *) ((eflags & 4) ? (void *) __get_PSP() : (void *) (fault_data_extra + 1));
+    DBGOUT("***FAULT***\r\neflags = 0x0%x\r\nPSP = %p\r\nType: ", eflags, __get_PSP());
     switch (fault) {
     case NMI:
         DBGOUT("NMI\r\n");
@@ -49,7 +54,7 @@ void general_C_handler(enum FaultType fault, struct fault_data_t * fault_data2)
         DBGOUT("Unknown\r\n");
     }
     
-    print_fault_data(fault_data1, fault_data2);
+    print_fault_data(fault_data_cpu, fault_data_extra);
     
     DBGOUT("HALTING\r\n");
     BoardExceptionHandler(-1);
diff --git a/arch/arm/lpc17xx/startup.s b/arch/arm/lpc17xx/startup.s
index d0917b6..86365c1 100644
--- a/arch/arm/lpc17xx/startup.s
+++ b/arch/arm/lpc17xx/startup.s
@@ -169,9 +169,9 @@ UsageFault_Handler:
     MOV     R0, 6
     .type   general_handler, %function
 general_handler:
-    MOV     R1, SP
-    SUB     R1, #32
     PUSH    {R4-R11}
+    MOV     R1, SP
+    MOV     R2, LR
     MOV     R4, LR
     BL      general_C_handler
     AND     R0, #7