From cd72a950e0aaba0ea7e9cb1d03ff2f1ca0ca037a Mon Sep 17 00:00:00 2001 From: Roger Quadros Date: Tue, 11 Oct 2022 14:50:02 +0300 Subject: [PATCH] mtd: rawnand: omap_gpmc: Optimize NAND reads Rename omap_nand_read() to omap_nand_read_buf() to reflect actual behaviour. Use FIFO read address instead of raw read address for reads. The GPMC automatically converts 32-bit/16-bit reads to NAND device specific reads (8/16 bit). Use the largest possible read granularity size for more efficient reads. Signed-off-by: Roger Quadros Reviewed-by: Michael Trimarchi Link: https://lore.kernel.org/all/20221011115012.6181-5-rogerq@kernel.org Signed-off-by: Dario Binacchi --- drivers/mtd/nand/raw/omap_gpmc.c | 49 ++++++++++++++++++-------------- 1 file changed, 28 insertions(+), 21 deletions(-) diff --git a/drivers/mtd/nand/raw/omap_gpmc.c b/drivers/mtd/nand/raw/omap_gpmc.c index d62c3e6fce..b36fe762b3 100644 --- a/drivers/mtd/nand/raw/omap_gpmc.c +++ b/drivers/mtd/nand/raw/omap_gpmc.c @@ -55,6 +55,7 @@ struct omap_nand_info { enum omap_ecc ecc_scheme; uint8_t cs; uint8_t ws; /* wait status pin (0,1) */ + void __iomem *fifo; }; /* We are wasting a bit of memory but al least we are safe */ @@ -350,6 +351,20 @@ static int omap_calculate_ecc(struct mtd_info *mtd, const uint8_t *dat, return 0; } +static inline void omap_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + struct omap_nand_info *info = nand_get_controller_data(chip); + u32 alignment = ((uintptr_t)buf | len) & 3; + + if (alignment & 1) + readsb(info->fifo, buf, len); + else if (alignment & 3) + readsw(info->fifo, buf, len >> 1); + else + readsl(info->fifo, buf, len >> 2); +} + #ifdef CONFIG_NAND_OMAP_GPMC_PREFETCH #define PREFETCH_CONFIG1_CS_SHIFT 24 @@ -415,7 +430,7 @@ static int __read_prefetch_aligned(struct nand_chip *chip, uint32_t *buf, int le cnt = PREFETCH_STATUS_FIFO_CNT(cnt); for (i = 0; i < cnt / 4; i++) { - *buf++ = readl(CONFIG_SYS_NAND_BASE); + *buf++ = readl(info->fifo); len -= 4; } } while (len); @@ -425,16 +440,6 @@ static int __read_prefetch_aligned(struct nand_chip *chip, uint32_t *buf, int le return 0; } -static inline void omap_nand_read(struct mtd_info *mtd, uint8_t *buf, int len) -{ - struct nand_chip *chip = mtd_to_nand(mtd); - - if (chip->options & NAND_BUSWIDTH_16) - nand_read_buf16(mtd, buf, len); - else - nand_read_buf(mtd, buf, len); -} - static void omap_nand_read_prefetch(struct mtd_info *mtd, uint8_t *buf, int len) { int ret; @@ -447,7 +452,7 @@ static void omap_nand_read_prefetch(struct mtd_info *mtd, uint8_t *buf, int len) */ head = ((uintptr_t)buf) % 4; if (head) { - omap_nand_read(mtd, buf, head); + omap_nand_read_buf(mtd, buf, head); buf += head; len -= head; } @@ -461,10 +466,10 @@ static void omap_nand_read_prefetch(struct mtd_info *mtd, uint8_t *buf, int len) ret = __read_prefetch_aligned(chip, (uint32_t *)buf, len - tail); if (ret < 0) { /* fallback in case the prefetch engine is busy */ - omap_nand_read(mtd, buf, len); + omap_nand_read_buf(mtd, buf, len); } else if (tail) { buf += len - tail; - omap_nand_read(mtd, buf, tail); + omap_nand_read_buf(mtd, buf, tail); } } #endif /* CONFIG_NAND_OMAP_GPMC_PREFETCH */ @@ -1001,6 +1006,8 @@ int board_nand_init(struct nand_chip *nand) int32_t gpmc_config = 0; int cs = cs_next++; int err = 0; + struct omap_nand_info *info; + /* * xloader/Uboot's gpmc configuration would have configured GPMC for * nand type of memory. The following logic scans and latches on to the @@ -1029,9 +1036,12 @@ int board_nand_init(struct nand_chip *nand) nand->IO_ADDR_R = (void __iomem *)&gpmc_cfg->cs[cs].nand_dat; nand->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_cmd; - omap_nand_info[cs].control = NULL; - omap_nand_info[cs].cs = cs; - omap_nand_info[cs].ws = wscfg[cs]; + + info = &omap_nand_info[cs]; + info->control = NULL; + info->cs = cs; + info->ws = wscfg[cs]; + info->fifo = (void __iomem *)CONFIG_SYS_NAND_BASE; nand_set_controller_data(nand, &omap_nand_info[cs]); nand->cmd_ctrl = omap_nand_hwcontrol; nand->options |= NAND_NO_PADDING | NAND_CACHEPRG; @@ -1062,10 +1072,7 @@ int board_nand_init(struct nand_chip *nand) #ifdef CONFIG_NAND_OMAP_GPMC_PREFETCH nand->read_buf = omap_nand_read_prefetch; #else - if (nand->options & NAND_BUSWIDTH_16) - nand->read_buf = nand_read_buf16; - else - nand->read_buf = nand_read_buf; + nand->read_buf = omap_nand_read_buf; #endif nand->dev_ready = omap_dev_ready; -- 2.39.5