System Calls cleanup, multiple Processes and context switch

[cortex-from-scratch] / start.asm

diff --git a/start.asm b/start.asm
index 180f9a4..65b67f5 100644 (file)
--- a/start.asm
+++ b/start.asm
@@ -5,12 +5,15 @@
  * Initial version 
  * 
  * $DESCRIPTION$
- *
- * */
+ */
+
+/* _start sets up the stack and jumps to the reset vector */
+
        .equ STACK_TOP, 0x20010000 /* placed at 64kB, top of SRAM */
        .text
        .global _start
        .global reset, nmi, hardfault
+       .global pendsv_handler
        .code 16
        .syntax unified
 _start:
@@ -26,22 +29,18 @@ reset:
 /* These are consequently the nmi and hardfault vector handlers
    before booting and entering main, these can actually be called
    (machine somehow has a failure). That's why they are included here.
-   Later the interrupt vector
-   will be relocated to SRAM and the will be copied / modified.  */
+   Later the interrupt vector will be relocated to SRAM and modified.  */
+
 
 nmi:
        b nmi
 
-hardfault: 
-       b hardfault
-.global stub
-stub:
-       ldr R0,=10
-       mov R1,#0
-       ldc2 11, cr0, [r1, #4]
-       udiv.w R2, R0, R1 
-
-       .data
-       .word 'x' 
+hardfault:
+       mov r5, 9
+       b hardfault2
+
+hardfault2:
+       b hardfault2
+
        .end