+ /* disable pecr protection */
+ write_uint32(sl->q_buf, 0x89abcdef);
+ stlink_write_mem32(sl, STM32L_FLASH_PEKEYR, sizeof(uint32_t));
+ write_uint32(sl->q_buf, 0x02030405);
+ stlink_write_mem32(sl, STM32L_FLASH_PEKEYR, sizeof(uint32_t));
+
+ /* check pecr.pelock is cleared */
+ stlink_read_mem32(sl, STM32L_FLASH_PECR, sizeof(uint32_t));
+ val = read_uint32(sl->q_buf, 0);
+ if (val & (1 << 0)) {
+ fprintf(stderr, "pecr.pelock not clear\n");
+ return -1;
+ }
+
+ /* unlock program memory */
+ write_uint32(sl->q_buf, 0x8c9daebf);
+ stlink_write_mem32(sl, STM32L_FLASH_PRGKEYR, sizeof(uint32_t));
+ write_uint32(sl->q_buf, 0x13141516);
+ stlink_write_mem32(sl, STM32L_FLASH_PRGKEYR, sizeof(uint32_t));
+
+ /* check pecr.prglock is cleared */
+ stlink_read_mem32(sl, STM32L_FLASH_PECR, sizeof(uint32_t));
+ val = read_uint32(sl->q_buf, 0);
+ if (val & (1 << 1)) {
+ fprintf(stderr, "pecr.prglock not clear\n");
+ return -1;
+ }
+
+ /* write a word in program memory */
+ for (off = 0; off < len; off += sizeof(uint32_t)) {
+ if (sl->verbose >= 1) {
+ if ((off & (sl->flash_pgsz - 1)) == 0) {
+ /* show progress. writing procedure is slow
+ and previous errors are misleading */
+ const uint32_t pgnum = off / sl->flash_pgsz;
+ const uint32_t pgcount = len / sl->flash_pgsz;
+ fprintf(stdout, "%u pages written out of %u\n", pgnum, pgcount);
+ }
+ }
+
+ memcpy(sl->q_buf, (const void*)(base + off), sizeof(uint32_t));
+ stlink_write_mem32(sl, addr + off, sizeof(uint32_t));
+
+ /* wait for sr.busy to be cleared */
+ while (1) {
+ stlink_read_mem32(sl, STM32L_FLASH_SR, sizeof(uint32_t));
+ if ((read_uint32(sl->q_buf, 0) & (1 << 0)) == 0) break ;
+ }