fix: nand: Replace hardcoded page chunk size with calculated one

Replace the hardcoded value of page chink with value that
depends on flash page size and ECC strength.
This fixes nand access errors for 2K page flashes with 8-bit ECC.
Move the initial flash commannd function assignment past the ECC
structures initialization for eliminating usage of hardcoded page
chunk size value.

Signed-off-by: Konstantin Porotchkin <kostap@marvell.com>
Reviewed-by: Igal Liberman <igall@marvell.com>
Cc: Stefan Roese <sr@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Signed-off-by: Stefan Roese <sr@denx.de>

drivers/mtd/nand/pxa3xx_nand.c

@@ -24,7 +24,6 @@ DECLARE_GLOBAL_DATA_PTR;
 #define TIMEOUT_DRAIN_FIFO	5	/* in ms */
 #define	CHIP_DELAY_TIMEOUT	200
 #define NAND_STOP_DELAY		40
-#define PAGE_CHUNK_SIZE		(2048)
 
 /*
  * Define a buffer size for the initial command that detects the flash device:
@@ -703,7 +702,7 @@ static void set_command_address(struct pxa3xx_nand_info *info,
 		unsigned int page_size, uint16_t column, int page_addr)
 {
 	/* small page addr setting */
-	if (page_size < PAGE_CHUNK_SIZE) {
+	if (page_size < info->chunk_size) {
 		info->ndcb1 = ((page_addr & 0xFFFFFF) << 8)
 				| (column & 0xFF);
 
@@ -813,9 +812,9 @@ static int prepare_set_command(struct pxa3xx_nand_info *info, int command,
 		 * which is either naked-read or last-read according to the
 		 * state.
 		 */
-		if (mtd->writesize == PAGE_CHUNK_SIZE) {
+		if (mtd->writesize == info->chunk_size) {
 			info->ndcb0 |= NDCB0_DBC | (NAND_CMD_READSTART << 8);
-		} else if (mtd->writesize > PAGE_CHUNK_SIZE) {
+		} else if (mtd->writesize > info->chunk_size) {
 			info->ndcb0 |= NDCB0_DBC | (NAND_CMD_READSTART << 8)
 					| NDCB0_LEN_OVRD
 					| NDCB0_EXT_CMD_TYPE(ext_cmd_type);
@@ -835,7 +834,7 @@ static int prepare_set_command(struct pxa3xx_nand_info *info, int command,
 		 * Multiple page programming needs to execute the initial
 		 * SEQIN command that sets the page address.
 		 */
-		if (mtd->writesize > PAGE_CHUNK_SIZE) {
+		if (mtd->writesize > info->chunk_size) {
 			info->ndcb0 |= NDCB0_CMD_TYPE(0x1)
 				| NDCB0_EXT_CMD_TYPE(ext_cmd_type)
 				| addr_cycle
@@ -860,7 +859,7 @@ static int prepare_set_command(struct pxa3xx_nand_info *info, int command,
 		}
 
 		/* Second command setting for large pages */
-		if (mtd->writesize > PAGE_CHUNK_SIZE) {
+		if (mtd->writesize > info->chunk_size) {
 			/*
 			 * Multiple page write uses the 'extended command'
 			 * field. This can be used to issue a command dispatch
@@ -1286,7 +1285,6 @@ static int pxa3xx_nand_config_ident(struct pxa3xx_nand_info *info)
 	struct pxa3xx_nand_platform_data *pdata = info->pdata;
 
 	/* Configure default flash values */
-	info->chunk_size = PAGE_CHUNK_SIZE;
 	info->reg_ndcr = 0x0; /* enable all interrupts */
 	info->reg_ndcr |= (pdata->enable_arbiter) ? NDCR_ND_ARB_EN : 0;
 	info->reg_ndcr |= NDCR_RD_ID_CNT(READ_ID_BYTES);
@@ -1503,21 +1501,6 @@ static int pxa3xx_nand_scan(struct mtd_info *mtd)
 	chip->bbt_md = &bbt_mirror_descr;
 #endif
 
-	/*
-	 * If the page size is bigger than the FIFO size, let's check
-	 * we are given the right variant and then switch to the extended
-	 * (aka splitted) command handling,
-	 */
-	if (mtd->writesize > PAGE_CHUNK_SIZE) {
-		if (info->variant == PXA3XX_NAND_VARIANT_ARMADA370) {
-			chip->cmdfunc = nand_cmdfunc_extended;
-		} else {
-			dev_err(&info->pdev->dev,
-				"unsupported page size on this variant\n");
-			return -ENODEV;
-		}
-	}
-
 	if (pdata->ecc_strength && pdata->ecc_step_size) {
 		ecc_strength = pdata->ecc_strength;
 		ecc_step = pdata->ecc_step_size;
@@ -1537,6 +1520,21 @@ static int pxa3xx_nand_scan(struct mtd_info *mtd)
 	if (ret)
 		return ret;
 
+	/*
+	 * If the page size is bigger than the FIFO size, let's check
+	 * we are given the right variant and then switch to the extended
+	 * (aka split) command handling,
+	 */
+	if (mtd->writesize > info->chunk_size) {
+		if (info->variant == PXA3XX_NAND_VARIANT_ARMADA370) {
+			chip->cmdfunc = nand_cmdfunc_extended;
+		} else {
+			dev_err(&info->pdev->dev,
+				"unsupported page size on this variant\n");
+			return -ENODEV;
+		}
+	}
+
 	/* calculate addressing information */
 	if (mtd->writesize >= 2048)
 		host->col_addr_cycles = 2;