+#define CODE_BREAK_NUM 6
+
+#define CODE_BREAK_LOW 0x01
+#define CODE_BREAK_HIGH 0x02
+
+struct code_hw_breakpoint {
+ stm32_addr_t addr;
+ int type;
+};
+
+struct code_hw_breakpoint code_breaks[CODE_BREAK_NUM];
+
+static void init_code_breakpoints(struct stlink* sl) {
+ memset(sl->q_buf, 0, 4);
+ sl->q_buf[0] = 0x03; // KEY | ENABLE
+ stlink_write_mem32(sl, 0xe0002000, 4);
+
+ memset(sl->q_buf, 0, 4);
+ for(int i = 0; i < CODE_BREAK_NUM; i++) {
+ code_breaks[i].type = 0;
+ stlink_write_mem32(sl, 0xe0002008 + i * 4, 4);
+ }
+}
+
+static int update_code_breakpoint(struct stlink* sl, stm32_addr_t addr, int set) {
+ stm32_addr_t fpb_addr = addr & ~0x3;
+ int type = addr & 0x2 ? CODE_BREAK_HIGH : CODE_BREAK_LOW;
+
+ if(addr & 1) {
+ fprintf(stderr, "update_code_breakpoint: unaligned address %08x\n", addr);
+ return -1;
+ }
+
+ int id = -1;
+ for(int i = 0; i < CODE_BREAK_NUM; i++) {
+ if(fpb_addr == code_breaks[i].addr ||
+ (set && code_breaks[i].type == 0)) {
+ id = i;
+ break;
+ }
+ }
+
+ if(id == -1) {
+ if(set) return -1; // Free slot not found
+ else return 0; // Breakpoint is already removed
+ }
+
+ struct code_hw_breakpoint* brk = &code_breaks[id];
+
+ brk->addr = fpb_addr;
+
+ if(set) brk->type |= type;
+ else brk->type &= ~type;
+
+ memset(sl->q_buf, 0, 4);
+
+ if(brk->type == 0) {
+ #ifdef DEBUG
+ printf("clearing hw break %d\n", id);
+ #endif
+
+ stlink_write_mem32(sl, 0xe0002008 + id * 4, 4);
+ } else {
+ sl->q_buf[0] = ( brk->addr & 0xff) | 1;
+ sl->q_buf[1] = ((brk->addr >> 8) & 0xff);
+ sl->q_buf[2] = ((brk->addr >> 16) & 0xff);
+ sl->q_buf[3] = ((brk->addr >> 24) & 0xff) | (brk->type << 6);
+
+ #ifdef DEBUG
+ printf("setting hw break %d at %08x (%d)\n",
+ id, brk->addr, brk->type);
+ printf("reg %02x %02x %02x %02x\n",
+ sl->q_buf[3], sl->q_buf[2], sl->q_buf[1], sl->q_buf[0]);
+ #endif
+
+ stlink_write_mem32(sl, 0xe0002008 + id * 4, 4);
+ }
+
+ return 0;
+}
+