[MTD] NAND: Add ECC debugging for CAFÉ

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

diff --git a/drivers/mtd/nand/cafe_ecc.c b/drivers/mtd/nand/cafe_ecc.c
index 4621460..2d29265 100644 (file)
--- a/drivers/mtd/nand/cafe_ecc.c
+++ b/drivers/mtd/nand/cafe_ecc.c
@@ -19,6 +19,7 @@
  */
 
 #include <linux/kernel.h>
+#include <linux/module.h>
 #include <linux/errno.h>
 
 static unsigned short gf4096_mul(unsigned short, unsigned short);
@@ -1322,16 +1323,43 @@ void correct_12bit_symbol(unsigned char *buf, unsigned short sym,
                buf[2+(3*(sym-2))/2] ^= (val >> 8);
                buf[3+(3*(sym-2))/2] ^= (val & 0xff);
        }
-
-               
 }
 
+static int debugecc = 0;
+module_param(debugecc, int, 0644);
+
 int cafe_correct_ecc(unsigned char *buf,
                     unsigned short *chk_syndrome_list)
 {
        unsigned short err_info[9];
        int i;
 
+       if (debugecc) {
+               printk(KERN_WARNING "cafe_correct_ecc invoked. Syndromes %x %x %x %x %x %x %x %x\n",
+                      chk_syndrome_list[0], chk_syndrome_list[1],
+                      chk_syndrome_list[2], chk_syndrome_list[3],
+                      chk_syndrome_list[4], chk_syndrome_list[5],
+                      chk_syndrome_list[6], chk_syndrome_list[7]);
+               for (i=0; i < 2048; i+=16) {
+                       printk(KERN_WARNING "D %04x: %02x %02x %02x %02x %02x %02x %02x %02x  %02x %02x %02x %02x %02x %02x %02x %02x\n",
+                              i,
+                              buf[i], buf[i+1], buf[i+2], buf[i+3],
+                              buf[i+4], buf[i+5], buf[i+6], buf[i+7],
+                              buf[i+8], buf[i+9], buf[i+10], buf[i+11],
+                              buf[i+12], buf[i+13], buf[i+14], buf[i+15]);
+               }
+               for ( ; i < 2112; i+=16) {
+                       printk(KERN_WARNING "O   %02x: %02x %02x %02x %02x %02x %02x %02x %02x  %02x %02x %02x %02x %02x %02x %02x %02x\n",
+                              i - 2048,
+                              buf[i], buf[i+1], buf[i+2], buf[i+3],
+                              buf[i+4], buf[i+5], buf[i+6], buf[i+7],
+                              buf[i+8], buf[i+9], buf[i+10], buf[i+11],
+                              buf[i+12], buf[i+13], buf[i+14], buf[i+15]);
+               }
+       }
+                       
+
+
        if (chk_no_err_only(chk_syndrome_list, err_info) &&
            chk_1_err_only(chk_syndrome_list, err_info) &&
            chk_2_err_only(chk_syndrome_list, err_info) &&
@@ -1340,8 +1368,13 @@ int cafe_correct_ecc(unsigned char *buf,
                return -EIO;
        }
 
-       for (i=0; i < err_info[0]; i++)
+       for (i=0; i < err_info[0]; i++) {
+               if (debugecc)
+                       printk(KERN_WARNING "Correct symbol %d with 0x%03x\n",
+                              err_info[1+i], err_info[5+i]);
+
                correct_12bit_symbol(buf, err_info[1+i], err_info[5+i]);
+       }
 
        return err_info[0];
 }