cpu/gowin_emcu: Use crt0.c from cortex_m3.

enjoy-digital · Jan 4, 2024 · 386854c · 386854c
1 parent de6fbf1
commit 386854c
Showing 1 changed file with 59 additions and 8 deletions.
diff --git a/litex/soc/cores/cpu/gowin_emcu/crt0.c b/litex/soc/cores/cpu/gowin_emcu/crt0.c
@@ -8,6 +8,10 @@ void _start(void);
 void default_handler(void);
 
 void _start(void) {
+    __asm__(
+        "mov r0, %0\n"
+        "mov sp, r0\n" : : "r" (&_fstack)
+    );
     uint32_t *y = &_fdata_rom;
     for (uint32_t *x = &_fdata; x < &_edata; x ++)
         *x = *y ++;
@@ -22,26 +26,73 @@ void _start(void) {
     while(1);
 }
 
+
 void default_handler(void) {
     while(1);
 }
 
-
 const void* isr_vector[] __attribute__((__used__)) __attribute__((section(".isr_vector"))) = {
     &_fstack,
-    _start,
+    _start, // reset
+    default_handler, // nmi
+    default_handler, // hard fault
+    default_handler, // mem manage
+    default_handler, // bus fault
+    default_handler, // usage fault
+    (void *) 0x55, // reserved
+    0, // reserved
+    0, // reserved
+    0, // reserved
+    default_handler, // svc
+    default_handler, // debug mon
+    0, // reserved
+    default_handler, // pend sv
+    default_handler, // systick
+    // external
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
+    default_handler,
     default_handler,
     default_handler,
     default_handler,
     default_handler,
     default_handler,
-    0,
-    0,
-    0,
-    0,
     default_handler,
     default_handler,
-    0,
     default_handler,
-    default_handler
 };
+
+__asm__ (
+"__gnu_thumb1_case_uhi:\n"
+"push    {r0, r1}\n"
+"mov     r1, lr\n"
+"lsrs    r1, r1, #1\n"
+"lsls    r0, r0, #1\n"
+"lsls    r1, r1, #1\n"
+"ldrh    r1, [r1, r0]\n"
+"lsls    r1, r1, #1\n"
+"add     lr, lr, r1\n"
+"pop     {r0, r1}\n"
+"bx      lr\n"
+);