mtd: nand: mxs check maximum ecc that platfrom supports

Check maximum ecc strength for each platfrom to avoid the calculated ecc
exceed the limitation.

Signed-off-by: Peng Fan <Peng.Fan@freescale.com>
Signed-off-by: Han Xu <b45815@freescale.com>
Tested-By: Tim Harvey <tharvey at gateworks.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Acked-by: Scott Wood <scottwood@freescale.com>
Cc: Stefano Babic <sbabic@denx.de>

diff --git a/drivers/mtd/nand/mxs_nand.c b/drivers/mtd/nand/mxs_nand.c
index 1d68901..f15cf36 100644 (file)
--- a/drivers/mtd/nand/mxs_nand.c
+++ b/drivers/mtd/nand/mxs_nand.c
@@ -149,6 +149,13 @@ static inline uint32_t mxs_nand_get_ecc_strength(uint32_t page_data_size,
                                                uint32_t page_oob_size)
 {
        int ecc_strength;
+       int max_ecc_strength_supported;
+
+       /* Refer to Chapter 17 for i.MX6DQ, Chapter 18 for i.MX6SX */
+       if (is_cpu_type(MXC_CPU_MX6SX))
+               max_ecc_strength_supported = 62;
+       else
+               max_ecc_strength_supported = 40;
 
        /*
         * Determine the ECC layout with the formula:
@@ -162,7 +169,7 @@ static inline uint32_t mxs_nand_get_ecc_strength(uint32_t page_data_size,
                        / (galois_field *
                           mxs_nand_ecc_chunk_cnt(page_data_size));
 
-       return round_down(ecc_strength, 2);
+       return min(round_down(ecc_strength, 2), max_ecc_strength_supported);
 }
 
 static inline uint32_t mxs_nand_get_mark_offset(uint32_t page_data_size,