From 3f225b7f52c428e6dccfd28f4cdd93dfe1c936c4 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Antoine=20T=C3=A9nart?= Date: Wed, 21 Oct 2015 10:29:02 +0200 Subject: [PATCH] mtd: pxa3xx_nand: add helpers to setup the timings Add helpers to setup the timings in the pxa3xx driver. These helpers allow to either make use of the nand framework nand_sdr_timings or the pxa3xx specific pxa3xx_nand_host, for compatibility reasons. Signed-off-by: Antoine Tenart Acked-by: Ezequiel Garcia Signed-off-by: Brian Norris --- drivers/mtd/nand/pxa3xx_nand.c | 122 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 122 insertions(+) diff --git a/drivers/mtd/nand/pxa3xx_nand.c b/drivers/mtd/nand/pxa3xx_nand.c index 91605c1..54f9283 100644 --- a/drivers/mtd/nand/pxa3xx_nand.c +++ b/drivers/mtd/nand/pxa3xx_nand.c @@ -418,6 +418,128 @@ static void pxa3xx_nand_set_timing(struct pxa3xx_nand_host *host, nand_writel(info, NDTR1CS0, ndtr1); } +static void pxa3xx_nand_set_sdr_timing(struct pxa3xx_nand_host *host, + const struct nand_sdr_timings *t) +{ + struct pxa3xx_nand_info *info = host->info_data; + struct nand_chip *chip = &host->chip; + unsigned long nand_clk = clk_get_rate(info->clk); + uint32_t ndtr0, ndtr1; + + u32 tCH_min = DIV_ROUND_UP(t->tCH_min, 1000); + u32 tCS_min = DIV_ROUND_UP(t->tCS_min, 1000); + u32 tWH_min = DIV_ROUND_UP(t->tWH_min, 1000); + u32 tWP_min = DIV_ROUND_UP(t->tWC_min - t->tWH_min, 1000); + u32 tREH_min = DIV_ROUND_UP(t->tREH_min, 1000); + u32 tRP_min = DIV_ROUND_UP(t->tRC_min - t->tREH_min, 1000); + u32 tR = chip->chip_delay * 1000; + u32 tWHR_min = DIV_ROUND_UP(t->tWHR_min, 1000); + u32 tAR_min = DIV_ROUND_UP(t->tAR_min, 1000); + + /* fallback to a default value if tR = 0 */ + if (!tR) + tR = 20000; + + ndtr0 = NDTR0_tCH(ns2cycle(tCH_min, nand_clk)) | + NDTR0_tCS(ns2cycle(tCS_min, nand_clk)) | + NDTR0_tWH(ns2cycle(tWH_min, nand_clk)) | + NDTR0_tWP(ns2cycle(tWP_min, nand_clk)) | + NDTR0_tRH(ns2cycle(tREH_min, nand_clk)) | + NDTR0_tRP(ns2cycle(tRP_min, nand_clk)); + + ndtr1 = NDTR1_tR(ns2cycle(tR, nand_clk)) | + NDTR1_tWHR(ns2cycle(tWHR_min, nand_clk)) | + NDTR1_tAR(ns2cycle(tAR_min, nand_clk)); + + info->ndtr0cs0 = ndtr0; + info->ndtr1cs0 = ndtr1; + nand_writel(info, NDTR0CS0, ndtr0); + nand_writel(info, NDTR1CS0, ndtr1); +} + +static int pxa3xx_nand_init_timings_compat(struct pxa3xx_nand_host *host, + unsigned int *flash_width, + unsigned int *dfc_width) +{ + struct nand_chip *chip = &host->chip; + struct pxa3xx_nand_info *info = host->info_data; + const struct pxa3xx_nand_flash *f = NULL; + int i, id, ntypes; + + ntypes = ARRAY_SIZE(builtin_flash_types); + + chip->cmdfunc(host->mtd, NAND_CMD_READID, 0x00, -1); + + id = chip->read_byte(host->mtd); + id |= chip->read_byte(host->mtd) << 0x8; + + for (i = 0; i < ntypes; i++) { + f = &builtin_flash_types[i]; + + if (f->chip_id == id) + break; + } + + if (i == ntypes) { + dev_err(&info->pdev->dev, "Error: timings not found\n"); + return -EINVAL; + } + + pxa3xx_nand_set_timing(host, f->timing); + + *flash_width = f->flash_width; + *dfc_width = f->dfc_width; + + return 0; +} + +static int pxa3xx_nand_init_timings_onfi(struct pxa3xx_nand_host *host, + int mode) +{ + const struct nand_sdr_timings *timings; + + mode = fls(mode) - 1; + if (mode < 0) + mode = 0; + + timings = onfi_async_timing_mode_to_sdr_timings(mode); + if (IS_ERR(timings)) + return PTR_ERR(timings); + + pxa3xx_nand_set_sdr_timing(host, timings); + + return 0; +} + +static int pxa3xx_nand_init(struct pxa3xx_nand_host *host) +{ + struct nand_chip *chip = &host->chip; + struct pxa3xx_nand_info *info = host->info_data; + unsigned int flash_width = 0, dfc_width = 0; + int mode, err; + + mode = onfi_get_async_timing_mode(chip); + if (mode == ONFI_TIMING_MODE_UNKNOWN) { + err = pxa3xx_nand_init_timings_compat(host, &flash_width, + &dfc_width); + if (err) + return err; + + if (flash_width == 16) { + info->reg_ndcr |= NDCR_DWIDTH_M; + chip->options |= NAND_BUSWIDTH_16; + } + + info->reg_ndcr |= (dfc_width == 16) ? NDCR_DWIDTH_C : 0; + } else { + err = pxa3xx_nand_init_timings_onfi(host, mode); + if (err) + return err; + } + + return 0; +} + /* * Set the data and OOB size, depending on the selected * spare and ECC configuration. -- 2.7.4