mtd: nand: pxa3xx: Fix READOOB implementation

Boris Brezillon · richardweinberger · commit fee4380f368e · 2018-01-06T23:06:58.000+01:00
In the current driver, OOB bytes are accessed in raw mode, and when a page access is done with NDCR_SPARE_EN set and NDCR_ECC_EN cleared, the driver must read the whole spare area (64 bytes in case of a 2k page, 16 bytes for a 512 page). The driver was only reading the free OOB bytes, which was leaving some unread data in the FIFO and was somehow leading to a timeout. We could patch the driver to read ->spare_size + ->ecc_size instead of just ->spare_size when READOOB is requested, but we'd better make in-band and OOB accesses consistent. Since the driver is always accessing in-band data in non-raw mode (with the ECC engine enabled), we should also access OOB data in this mode. That's particularly useful when using the BCH engine because in this mode the free OOB bytes are also ECC protected. Fixes: 43bcfd2 ("mtd: nand: pxa3xx: Add driver-specific ECC BCH support") Cc: stable@vger.kernel.org Reported-by: Sean Nyekjær <sean.nyekjaer@prevas.dk> Tested-by: Willy Tarreau <w@1wt.eu> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Acked-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> Tested-by: Sean Nyekjaer <sean.nyekjaer@prevas.dk> Acked-by: Robert Jarzmik <robert.jarzmik@free.fr> Signed-off-by: Richard Weinberger <richard@nod.at>
diff --git a/drivers/mtd/nand/pxa3xx_nand.c b/drivers/mtd/nand/pxa3xx_nand.c
@@ -963,6 +963,7 @@ static void prepare_start_command(struct pxa3xx_nand_info *info, int command)
 
 	switch (command) {
 	case NAND_CMD_READ0:
+	case NAND_CMD_READOOB:
 	case NAND_CMD_PAGEPROG:
 		info->use_ecc = 1;
 		break;
