spl mxc nand: Fix broken boot for correctable ECC errors

Do not stop boot as soon as an ECC error is detected. Only stop boot for
uncorrectable ECC errors.

This fixes boards no longer booting after some time because a NAND Flash bit has
flipped.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Cc: Scott Wood <scottwood@freescale.com>
Cc: Stefano Babic <sbabic@denx.de>
Signed-off-by: Scott Wood <scottwood@freescale.com>

diff --git a/nand_spl/nand_boot_fsl_nfc.c b/nand_spl/nand_boot_fsl_nfc.c
index 4c5a7feec1629aacc22d1c26ab1bd843339ea56c..ea05952eb5e1fd8c8617c742e8e1dc3f77e8332e 100644 (file)
--- a/nand_spl/nand_boot_fsl_nfc.c
+++ b/nand_spl/nand_boot_fsl_nfc.c
@@ -140,9 +140,21 @@ static void nfc_nand_data_output(void)
 static int nfc_nand_check_ecc(void)
 {
 #if defined(MXC_NFC_V1)
-       return readw(&nfc->ecc_status_result);
+       u16 ecc_status = readw(&nfc->ecc_status_result);
+       return (ecc_status & 0x3) == 2 || (ecc_status >> 2) == 2;
 #elif defined(MXC_NFC_V1_1)
-       return readl(&nfc->ecc_status_result);
+       u32 ecc_status = readl(&nfc->ecc_status_result);
+       int ecc_per_page = CONFIG_SYS_NAND_PAGE_SIZE / 512;
+       int err_limit = CONFIG_SYS_NAND_SPARE_SIZE / ecc_per_page > 16 ? 8 : 4;
+       int subpages = CONFIG_SYS_NAND_PAGE_SIZE / 512;
+
+       do {
+               if ((ecc_status & 0xf) > err_limit)
+                       return 1;
+               ecc_status >>= 4;
+       } while (--subpages);
+
+       return 0;
 #endif
 }