From a2a05c2f530c663f6f23cee1e57dc6d45a11a9e9 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 28 Nov 2018 14:27:36 +0900 Subject: mtd: rawnand: denali: remove ->dev_ready() hook The Denali NAND IP has no way to read out the current signal level of the R/B# pin. Instead, denali_dev_ready() checks if the R/B# transition has already happened. (The INTR__INT_ACT interrupt is asserted at the rising edge of the R/B# pin.) It is not a correct way to implement the ->dev_ready() hook. In fact, it has a drawback; in the nand_scan_ident phase, the chip detection iterates over maxchips until it fails to find a homogeneous chip. For the last loop, nand_reset() fails if no chip is there. If ->dev_ready hook exists, nand_command(_lp) calls nand_wait_ready() after NAND_CMD_RESET. However, we know denali_dev_ready() never returns 1 unless there exists a chip that toggles R/B# in that chip select. Then, nand_wait_ready() just ends up with wasting 400 msec, in the end, shows the "timeout while waiting for chip to become ready" warning. Let's remove the mis-implemented dev_ready hook, and fallback to sending the NAND_CMD_STATUS and nand_wait_status_ready(), which bails out more quickly. Signed-off-by: Masahiro Yamada Signed-off-by: Miquel Raynal --- drivers/mtd/nand/raw/denali.c | 23 +---------------------- 1 file changed, 1 insertion(+), 22 deletions(-) (limited to 'drivers/mtd/nand/raw/denali.c') diff --git a/drivers/mtd/nand/raw/denali.c b/drivers/mtd/nand/raw/denali.c index bad3b8ad5e0a..3f8ee9245adb 100644 --- a/drivers/mtd/nand/raw/denali.c +++ b/drivers/mtd/nand/raw/denali.c @@ -204,18 +204,6 @@ static uint32_t denali_wait_for_irq(struct denali_nand_info *denali, return denali->irq_status; } -static uint32_t denali_check_irq(struct denali_nand_info *denali) -{ - unsigned long flags; - uint32_t irq_status; - - spin_lock_irqsave(&denali->irq_lock, flags); - irq_status = denali->irq_status; - spin_unlock_irqrestore(&denali->irq_lock, flags); - - return irq_status; -} - static void denali_read_buf(struct nand_chip *chip, uint8_t *buf, int len) { struct mtd_info *mtd = nand_to_mtd(chip); @@ -288,8 +276,7 @@ static void denali_cmd_ctrl(struct nand_chip *chip, int dat, unsigned int ctrl) return; /* - * Some commands are followed by chip->legacy.dev_ready or - * chip->legacy.waitfunc. + * Some commands are followed by chip->legacy.waitfunc. * irq_status must be cleared here to catch the R/B# interrupt later. */ if (ctrl & NAND_CTRL_CHANGE) @@ -298,13 +285,6 @@ static void denali_cmd_ctrl(struct nand_chip *chip, int dat, unsigned int ctrl) denali->host_write(denali, DENALI_BANK(denali) | type, dat); } -static int denali_dev_ready(struct nand_chip *chip) -{ - struct denali_nand_info *denali = mtd_to_denali(nand_to_mtd(chip)); - - return !!(denali_check_irq(denali) & INTR__INT_ACT); -} - static int denali_check_erased_page(struct mtd_info *mtd, struct nand_chip *chip, uint8_t *buf, unsigned long uncor_ecc_flags, @@ -1360,7 +1340,6 @@ int denali_init(struct denali_nand_info *denali) chip->legacy.read_byte = denali_read_byte; chip->legacy.write_byte = denali_write_byte; chip->legacy.cmd_ctrl = denali_cmd_ctrl; - chip->legacy.dev_ready = denali_dev_ready; chip->legacy.waitfunc = denali_waitfunc; if (features & FEATURES__INDEX_ADDR) { -- cgit v1.2.3-55-g7522