cowond2.diff

diff --git a/firmware/drivers/fat.c b/firmware/drivers/fat.c
index 44e5ab2..2659c79 100644
--- a/firmware/drivers/fat.c
+++ b/firmware/drivers/fat.c
@@ -364,8 +364,9 @@ void dc_writeback_callback(IF_MV(int volume,) unsigned long sector, void *buf)
         int rc = storage_write_sectors(IF_MD(fat_bpb->drive,) sector, 1, buf);
         if (rc < 0)
         {
+            extern const char *sd_msg;
             panicf("%s() - Could not write sector %ld"
-                   " (error %d)\n", __func__, sector, rc);
+                   " (error %d %s)\n", __func__, sector, rc, sd_msg);
         }
 
         if (--copies == 0)
diff --git a/firmware/target/arm/tcc780x/sd-tcc780x.c b/firmware/target/arm/tcc780x/sd-tcc780x.c
index b7abea8..9b42501 100644
--- a/firmware/target/arm/tcc780x/sd-tcc780x.c
+++ b/firmware/target/arm/tcc780x/sd-tcc780x.c
@@ -511,6 +511,8 @@ sd_read_error:
     }
 }
 
+const char *sd_msg;
+
 int sd_write_sectors(IF_MD(int card_no,) unsigned long start, int count,
                       const void* outbuf)
 {
@@ -524,8 +526,11 @@ int sd_write_sectors(IF_MD(int card_no,) unsigned long start, int count,
     const unsigned char *buf_end;
     bool aligned;
 
+    sd_msg = "sd_write_sectors";
+
     if ((card_no == CARD_NUM_SLOT) && (GPIOA & 0x10))
     {
+        sd_msg = "EC_WRITE_PROTECT";
         /* write protect tab set */
         return -EC_WRITE_PROTECT;
     }
@@ -537,6 +542,7 @@ int sd_write_sectors(IF_MD(int card_no,) unsigned long start, int count,
 sd_write_retry:
     if ((card_no == CARD_NUM_SLOT) && !card_detect_target())
     {
+        sd_msg = "EC_NOCARD";
         /* no external sd-card inserted */
         ret = -EC_NOCARD;
         goto sd_write_error;
@@ -546,6 +552,7 @@ sd_write_retry:
 
     if (currcard->initialized < 0)
     {
+        sd_msg = "init_err";
         ret = currcard->initialized;
         goto sd_write_error;
     }
@@ -553,7 +560,10 @@ sd_write_retry:
     ret = sd_wait_for_state(SD_TRAN, EC_TRAN_WRITE_ENTRY);
     
     if (ret < 0)
+    {
+        sd_msg = "wait_error";
         goto sd_write_error;
+    }
 
     /* Use full SD clock for data transfer (PCK_SDMMC) */
     SDICLK = (1<<13) | (1<<12); /* bypass divider | enable */
@@ -570,7 +580,10 @@ sd_write_retry:
         ret = sd_command(SD_WRITE_MULTIPLE_BLOCK, start * 512, NULL, SDICMD_RES_TYPE1);
 
     if (ret < 0)
+    {
+        sd_msg = "cmd_error";
         goto sd_write_error;
+    }
 
     aligned = (((int)outbuf & 3) == 0);
 
@@ -602,6 +615,7 @@ sd_write_retry:
         /* Wait for the FIFO to empty */
         if (!sd_poll_status(SDISTATUS_FIFO_LOAD_REQ, 0x80000))
         {
+            sd_msg = "EC_FIFO_WR_EMPTY";
             ret = -EC_FIFO_WR_EMPTY;
             goto sd_write_error;
         }
@@ -611,17 +625,24 @@ sd_write_retry:
 
     if (!sd_poll_status(SDISTATUS_MULTIBLOCK_END, 0x80000))
     {
+        sd_msg = "EC_FIFO_WR_DONE";
         ret = -EC_FIFO_WR_DONE;
         goto sd_write_error;
     }
 
     ret = sd_command(SD_STOP_TRANSMISSION, 0, NULL, SDICMD_RES_TYPE1);
     if (ret < 0)
+    {
+        sd_msg = "stop_error";
         goto sd_write_error;
+    }
 
     ret = sd_wait_for_state(SD_TRAN, EC_TRAN_WRITE_EXIT);
     if (ret < 0)
+    {
+        sd_msg = "wait_error_2";
         goto sd_write_error;
+    }
 
     while (1)
     {