git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@450 35acf78f-673a-0410-8e92-d51de3d6d3f4

demos/ARMCM3-STM32F103-GCC/board.c

@@ -24,10 +24,11 @@
 #include "stm32_serial.h"
 
 /*
- * Hardware initialization goes here.
- * NOTE: Interrupts are still disabled.
+ * Early initialization code.
+ * This initialization is performed just after reset before BSS and DATA
+ * segments initialization.
  */
-void hwinit(void) {
+void hwinit0(void) {
 
   /*
    * Clocks and PLL initialization.
@@ -76,6 +77,14 @@ void hwinit(void) {
   GPIOD->CRL = VAL_GPIODCRL;
   GPIOD->CRH = VAL_GPIODCRH;
   GPIOD->ODR = VAL_GPIODODR;
+}
+
+/*
+ * Late initialization code.
+ * This initialization is performed after BSS and DATA segments initialization
+ * and before invoking the main() function.
+ */
+void hwinit1(void) {
 
   /*
    * NVIC/SCB initialization.
@@ -95,4 +104,9 @@ void hwinit(void) {
    * Other subsystems initialization.
    */
   InitSerial(0x80, 0x80, 0x80);
+
+  /*
+   * ChibiOS/RT initialization.
+   */
+  chSysInit();
 }

demos/ARMCM3-STM32F103-GCC/main.c

@@ -39,16 +39,11 @@ static msg_t Thread1(void *arg) {
 }
 
 /*
- * Entry point, the interrupts are disabled on entry.
+ * Entry point, note, the main() function is already a thread in the system
+ * on entry.
  */
 int main(int argc, char **argv) {
 
-  /*
-   * The main() function becomes a thread here then the interrupts are
-   * enabled and ChibiOS/RT goes live.
-   */
-  chSysInit();
-
   /*
    * Creates the blinker thread.
    */

ports/ARMCM3/crt0.s

@@ -47,6 +47,10 @@ ResetHandler:
         msr     PSP, r0
 //        ldr     r1, =__process_stack_size__
 //        sub     r0, r0, r1
+        /*
+         * Early initialization.
+         */
+        bl      hwinit0
         /*
          * Data initialization.
          * NOTE: It assumes that the DATA size is a multiple of 4.
@@ -82,9 +86,9 @@ bloop:
         msr     BASEPRI, r0
         cpsie   i
         /*
-         * Application-provided HW initialization routine.
+         * Late initialization.
          */
-        bl      hwinit
+        bl      hwinit1
         /*
          * main(0, NULL).
          */
@@ -92,3 +96,27 @@ bloop:
         mov     r1, r0
         bl      main
         bl      chSysHalt
+
+/*
+ * Default early initialization code. It is declared weak in order to be
+ * replaced by the real initialization code.
+ * Early initialization is performed just after reset before BSS and DATA
+ * segments initialization.
+ */
+.thumb_func
+.global hwinit0
+.weak hwinit0
+hwinit0:
+        bx      lr
+        
+/*
+ * Default late initialization code. It is declared weak in order to be
+ * replaced by the real initialization code.
+ * Late initialization is performed after BSS and DATA segments initialization
+ * and before invoking the main() function.
+ */
+.thumb_func
+.global hwinit1
+.weak hwinit1
+hwinit1:
+        bx      lr

readme.txt

@@ -75,6 +75,10 @@ Win32-MinGW            - ChibiOS/RT simulator and demo into a WIN32 process,
 *****************************************************************************
 
 *** 0.7.2 ***
+- CHANGE: Modified the CM3 startup file in order to implement an early
+  initializaiton phase: hwinit0, the late initialization phase is now named
+  hwinit1. The demo now initializes the PLL before initializing the BSS and
+  DATA segments, this greatly optimizes the system start up time.
 - Modified the STM32 demo makefile to use the latest YAGARTO toolchain as
   default (arm-elf-gcc).