Working wolfBoot test-app startup!

Author: dgarske

hal/nxp_t2080.c

@@ -1006,7 +1006,16 @@ int RAMFUNCTION hal_flash_write(uint32_t address, const uint8_t *data, int len)
      * in command mode (e.g. after a timeout or incomplete operation) */
     FLASH_IO8_WRITE(0, 0, AMD_CMD_RESET);
     ram_udelay(50);
-    ram_putchar('r'); /* checkpoint: reset done, starting loop */
+    ram_putchar('r'); /* checkpoint: reset done */
+
+    /* Diagnostic: read erased data before write to verify both chips respond.
+     * Expected 0xFFFF after erase. If high byte != 0xFF, chip may be dead. */
+    {
+        uint16_t erased = FLASH_IO16_READ(address / FLASH_SECTOR_SIZE, 0);
+        ram_putchar('{');
+        ram_puthex16(erased);
+        ram_putchar('}');
+    }
 
     pos = 0;
     while (len > 0) {
@@ -1058,13 +1067,27 @@ int RAMFUNCTION hal_flash_write(uint32_t address, const uint8_t *data, int len)
         }
         if (ret != 0) {
             uint16_t readback;
-            /* Reset flash to read-array mode BEFORE reading back data */
+            /* Write-to-Buffer-Abort-Reset: plain AMD_CMD_RESET (0xF0) is
+             * IGNORED during an active WBP or WBP-abort state. Must use
+             * the unlock + reset sequence per S29GL01GS datasheet. */
+            hal_flash_unlock_sector(sector);
             FLASH_IO8_WRITE(sector, 0, AMD_CMD_RESET);
             ram_udelay(50);
             /* Read back offset 0 to see if data was actually written */
             readback = FLASH_IO16_READ(sector, 0);
             ram_putchar('=');
             ram_puthex16(readback);
+            /* Verify flash exited command mode (second read should match) */
+            {
+                uint16_t verify = FLASH_IO16_READ(sector, 0);
+                if (readback != verify) {
+                    ram_putchar('!'); /* still in command mode */
+                    /* Try one more reset */
+                    hal_flash_unlock_sector(sector);
+                    FLASH_IO8_WRITE(sector, 0, AMD_CMD_RESET);
+                    ram_udelay(50);
+                }
+            }
             wolfBoot_printf("\nFlash Write: %s at sector %d (ret %d)\n",
                 ret == -2 ? "DQ5 error" : "Timeout", sector, ret);
             break;