Diff: nordic/bootloader_dfu/bootloader_util_arm.c

Revision:

69:61da91a52bd6

Parent:

66:b3680699d9a4

--- a/nordic/bootloader_dfu/bootloader_util_arm.c	Fri Sep 26 14:46:19 2014 +0100
+++ b/nordic/bootloader_dfu/bootloader_util_arm.c	Tue Nov 04 10:42:27 2014 +0000
@@ -17,16 +17,17 @@
 /**
  * @brief Function for aborting current handler mode and jump to to other application/bootloader.
  *
- * @details This functions will use the address provide (reset handler) to be executed after 
- *          handler mode is exited. It creates an initial stack to ensure correct reset behavior 
+ * @details This function will use the address provided (reset handler) to be executed after
+ *          handler mode is exited. It creates an initial stack to ensure correct reset behavior
  *          when the reset handler is executed.
  *
  * @param[in]  reset_handler  Address of the reset handler to be executed when handler mode exits.
  *
- * @note This function must never be called directly from 'C' but is intended only to be used from 
- *       \ref bootloader_util_reset. This function will never return but issue a reset into 
+ * @note This function must never be called directly from 'C' but is intended only to be used from
+ *       \ref bootloader_util_reset. This function will never return but issue a reset into
  *       provided address.
  */
+#ifdef TOOLCHAIN_ARM
 __asm void isr_abort(uint32_t reset_handler)
 {
 xPSR_RESET      EQU 0x21000000  ; Default value of xPSR after System Reset.
@@ -37,33 +38,59 @@
     MOV   R6, R0                ; Move address of reset handler to R6. Will be popped as PC when exiting ISR. Ensures the reset handler will be executed when exist ISR.
     LDR   R7,=xPSR_RESET        ; Move reset value of xPSR to R7. Will be popped as xPSR when exiting ISR.
     PUSH  {r4-r7}               ; Push everything to new stack to allow interrupt handler to fetch it on exiting the ISR.
-    
+
     LDR   R4,=MASK_ZEROS        ; Fill with zeros before jumping to reset handling. We be popped as R0 when exiting ISR (Cleaning up of the registers).
     LDR   R5,=MASK_ZEROS        ; Fill with zeros before jumping to reset handling. We be popped as R1 when exiting ISR (Cleaning up of the registers).
     LDR   R6,=MASK_ZEROS        ; Fill with zeros before jumping to reset handling. We be popped as R2 when exiting ISR (Cleaning up of the registers).
     LDR   R7,=MASK_ZEROS        ; Fill with zeros before jumping to reset handling. We be popped as R3 when exiting ISR (Cleaning up of the registers).
     PUSH  {r4-r7}               ; Push zeros (R4-R7) to stack to prepare for exiting the interrupt routine.
-    
+
     LDR   R0,=EXC_RETURN_CMD    ; Load the execution return command into register.
     BX    R0                    ; No return - Handler mode will be exited. Stack will be popped and execution will continue in reset handler initializing other application.
     ALIGN
 }
+#elif defined(TOOLCHAIN_GCC)
+void isr_abort(uint32_t reset_handler)
+{
+    asm(
+        ".equ xPSR_RESET, 0x21000000    \n\t"  /* Default value of xPSR after System Reset.       */
+        ".equ EXC_RETURN_CMD, 0xFFFFFFF9\n\t"  /* EXC_RETURN for ARM Cortex. When loaded to PC the current interrupt
+                                                * service routine (handler mode) willl exit and the stack will be
+                                                * popped. Execution will continue in thread mode. */
 
+        "LDR   R4,=MASK_ONES \n\t" /* Fill with ones before jumping to reset handling. We be popped as R12 when exiting ISR (Cleaning up the registers). */
+        "LDR   R5,=MASK_ONES \n\t" /* Fill with ones before jumping to reset handling. We be popped as LR when exiting ISR. Ensures no return to application. */
+        "MOV   R6, R0        \n\t" /* Move address of reset handler to R6. Will be popped as PC when exiting ISR. Ensures the reset handler will be executed when exist ISR. */
+        "LDR   R7,=xPSR_RESET\n\t" /* Move reset value of xPSR to R7. Will be popped as xPSR when exiting ISR. */
+        "PUSH  {r4-r7}       \n\t" /* Push everything to new stack to allow interrupt handler to fetch it on exiting the ISR. */
+
+        "LDR   R4,=MASK_ZEROS\n\t" /* Fill with zeros before jumping to reset handling. We be popped as R0 when exiting ISR (Cleaning up of the registers). */
+        "LDR   R5,=MASK_ZEROS\n\t" /* Fill with zeros before jumping to reset handling. We be popped as R1 when exiting ISR (Cleaning up of the registers). */
+        "LDR   R6,=MASK_ZEROS\n\t" /* Fill with zeros before jumping to reset handling. We be popped as R2 when exiting ISR (Cleaning up of the registers). */
+        "LDR   R7,=MASK_ZEROS\n\t" /* Fill with zeros before jumping to reset handling. We be popped as R3 when exiting ISR (Cleaning up of the registers). */
+        "PUSH  {r4-r7}       \n\t" /* Push zeros (R4-R7) to stack to prepare for exiting the interrupt routine. */
+
+        "LDR   R0,=EXC_RETURN_CMD\n\t" /* Load the execution return command into register. */
+        "BX    R0                \n\t" /* No return - Handler mode will be exited. Stack will be popped and execution will continue in reset handler initializing other application. */
+        );
+}
+#endif /* TOOLCHAIN_ARM */
 
 /**
  * @brief Function for aborting current application/bootloader jump to to other app/bootloader.
  *
- * @details This functions will use the address provide to swap the stack pointer and then load 
- *          the address of the reset handler to be executed. It will check current system mode 
+ * @details This function will use the address provided to swap the stack pointer and then load
+ *          the address of the reset handler to be executed. It will check current system mode
  *          (thread/handler) and if in thread mode it will reset into other application.
- *          If in handler mode \ref isr_abort will be executed to ensure correct exit of handler 
+ *          If in handler mode \ref isr_abort will be executed to ensure correct exit of handler
  *          mode and jump into reset handler of other application.
  *
- * @param[in]  start_addr  Start address of other application. This address must point to the 
+ * @param[in]  start_addr  Start address of other application. This address must point to the
                initial stack pointer of the application.
  *
  * @note This function will never return but issue a reset into provided application.
  */
+#ifdef TOOLCHAIN_ARM
 __asm static void bootloader_util_reset(uint32_t start_addr)
 {
 MASK_ONES       EQU 0xFFFFFFFF  ; Ones, to be loaded into register as default value before reset.
@@ -72,9 +99,9 @@
     LDR   R1, [R0]              ; Get App initial MSP for bootloader.
     MSR   MSP, R1               ; Set the main stack pointer to the applications MSP.
     LDR   R0,[R0, #0x04]        ; Load Reset handler into register 0.
-    
+
     LDR   R2, =MASK_ZEROS       ; Load zeros to R2
-    MRS   R3, IPSR              ; Load IPSR to R3 to check for handler or thread mode 
+    MRS   R3, IPSR              ; Load IPSR to R3 to check for handler or thread mode
     CMP   R2, R3                ; Compare, if 0 then we are in thread mode and can continue to reset handler of bootloader
     BNE   isr_abort             ; If not zero we need to exit current ISR and jump to reset handler of bootloader
 
@@ -83,7 +110,31 @@
     BX    R0                    ; Branch to reset handler of bootloader
     ALIGN
 }
+#elif defined(TOOLCHAIN_GCC)
+static void bootloader_util_reset(uint32_t start_addr)
+{
+    asm(
+        ".equ MASK_ONES,  0xFFFFFFFF\n\t" /* Ones, to be loaded into register as default value before reset.  */
+        ".equ MASK_ZEROS, 0x00000000\n\t" /* Zeros, to be loaded into register as default value before reset. */
 
+        "LDR   r1, [r0]       \n\t"       /* Get App initial MSP for bootloader.                              */
+        "MSR   MSP, r1        \n\t"       /* Set the main stack pointer to the applications MSP.              */
+        "LDR   r0,[r0, #0x04] \n\t"       /* Load Reset handler into register 0.                              */
+
+        "LDR   r2, =MASK_ZEROS\n\t"       /* Load zeros to R2                                                 */
+        "MRS   r3, IPSR       \n\t"       /* Load IPSR to R3 to check for handler or thread mode              */
+        "CMP   r2, r3         \n\t"       /* Compare, if 0 then we are in thread mode and can continue to reset handler of bootloader */
+        "BNE   isr_abort      \n\t"       /* If not zero we need to exit current ISR and jump to reset handler of bootloader */
+
+        "LDR   r4, =MASK_ONES \n\t"       /* Load ones to R4 to be placed in Link Register.                   */
+        "MOV   LR, r4         \n\t"       /* Clear the link register and set to ones to ensure no return.     */
+        "BX    r0             \n\t"       /* Branch to reset handler of bootloader                            */
+        : /* output operands */
+        : /* input operands */
+        : "r0", "r1", "r2", "r3", "r4" /* clobber list */
+        );
+}
+#endif /* TOOLCHAIN_ARM */
 
 void bootloader_util_app_start(uint32_t start_addr)
 {