From dd43e2a6bdfa2d21bb2cef07a93c43f819759888 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Fri, 12 Jan 2018 18:10:38 +0900 Subject: [PATCH] mmc: sdhci-cadence: add HS200 support Add HS200 timing setting and the MMC tuning callback. Signed-off-by: Masahiro Yamada Signed-off-by: Jaehoon Chung --- drivers/mmc/sdhci-cadence.c | 90 ++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 81 insertions(+), 9 deletions(-) diff --git a/drivers/mmc/sdhci-cadence.c b/drivers/mmc/sdhci-cadence.c index 921095b..0b174fc 100644 --- a/drivers/mmc/sdhci-cadence.c +++ b/drivers/mmc/sdhci-cadence.c @@ -52,6 +52,13 @@ #define SDHCI_CDNS_PHY_DLY_HSMMC 0x0c #define SDHCI_CDNS_PHY_DLY_STROBE 0x0d +/* + * The tuned val register is 6 bit-wide, but not the whole of the range is + * available. The range 0-42 seems to be available (then 43 wraps around to 0) + * but I am not quite sure if it is official. Use only 0 to 39 for safety. + */ +#define SDHCI_CDNS_MAX_TUNING_LOOP 40 + struct sdhci_cdns_plat { struct mmc_config cfg; struct mmc mmc; @@ -135,20 +142,18 @@ static void sdhci_cdns_set_control_reg(struct sdhci_host *host) * The mode should be decided by MMC_TIMING_* like Linux, but * U-Boot does not support timing. Use the clock frequency instead. */ - if (clock <= 26000000) + if (clock <= 26000000) { mode = SDHCI_CDNS_HRS06_MODE_SD; /* use this for Legacy */ - else if (clock <= 52000000) { + } else if (clock <= 52000000) { if (mmc->ddr_mode) mode = SDHCI_CDNS_HRS06_MODE_MMC_DDR; else mode = SDHCI_CDNS_HRS06_MODE_MMC_SDR; } else { - /* - * REVISIT: - * The IP supports HS200/HS400, revisit once U-Boot support it - */ - printf("unsupported frequency %d\n", clock); - return; + if (mmc->ddr_mode) + mode = SDHCI_CDNS_HRS06_MODE_MMC_HS400; + else + mode = SDHCI_CDNS_HRS06_MODE_MMC_HS200; } tmp = readl(plat->hrs_addr + SDHCI_CDNS_HRS06); @@ -161,6 +166,69 @@ static const struct sdhci_ops sdhci_cdns_ops = { .set_control_reg = sdhci_cdns_set_control_reg, }; +static int sdhci_cdns_set_tune_val(struct sdhci_cdns_plat *plat, + unsigned int val) +{ + void __iomem *reg = plat->hrs_addr + SDHCI_CDNS_HRS06; + u32 tmp; + + if (WARN_ON(!FIELD_FIT(SDHCI_CDNS_HRS06_TUNE, val))) + return -EINVAL; + + tmp = readl(reg); + tmp &= ~SDHCI_CDNS_HRS06_TUNE; + tmp |= FIELD_PREP(SDHCI_CDNS_HRS06_TUNE, val); + tmp |= SDHCI_CDNS_HRS06_TUNE_UP; + writel(tmp, reg); + + return readl_poll_timeout(reg, tmp, !(tmp & SDHCI_CDNS_HRS06_TUNE_UP), + 1); +} + +static int __maybe_unused sdhci_cdns_execute_tuning(struct udevice *dev, + unsigned int opcode) +{ + struct sdhci_cdns_plat *plat = dev_get_platdata(dev); + struct mmc *mmc = &plat->mmc; + int cur_streak = 0; + int max_streak = 0; + int end_of_streak = 0; + int i; + + /* + * This handler only implements the eMMC tuning that is specific to + * this controller. The tuning for SD timing should be handled by the + * SDHCI core. + */ + if (!IS_MMC(mmc)) + return -ENOTSUPP; + + if (WARN_ON(opcode != MMC_CMD_SEND_TUNING_BLOCK_HS200)) + return -EINVAL; + + for (i = 0; i < SDHCI_CDNS_MAX_TUNING_LOOP; i++) { + if (sdhci_cdns_set_tune_val(plat, i) || + mmc_send_tuning(mmc, opcode, NULL)) { /* bad */ + cur_streak = 0; + } else { /* good */ + cur_streak++; + if (cur_streak > max_streak) { + max_streak = cur_streak; + end_of_streak = i; + } + } + } + + if (!max_streak) { + dev_err(dev, "no tuning point found\n"); + return -EIO; + } + + return sdhci_cdns_set_tune_val(plat, end_of_streak - max_streak / 2); +} + +static struct dm_mmc_ops sdhci_cdns_mmc_ops; + static int sdhci_cdns_bind(struct udevice *dev) { struct sdhci_cdns_plat *plat = dev_get_platdata(dev); @@ -189,6 +257,10 @@ static int sdhci_cdns_probe(struct udevice *dev) host->ioaddr = plat->hrs_addr + SDHCI_CDNS_SRS_BASE; host->ops = &sdhci_cdns_ops; host->quirks |= SDHCI_QUIRK_WAIT_SEND_CMD; + sdhci_cdns_mmc_ops = sdhci_ops; +#ifdef MMC_SUPPORTS_TUNING + sdhci_cdns_mmc_ops.execute_tuning = sdhci_cdns_execute_tuning; +#endif ret = mmc_of_parse(dev, &plat->cfg); if (ret) @@ -223,5 +295,5 @@ U_BOOT_DRIVER(sdhci_cdns) = { .probe = sdhci_cdns_probe, .priv_auto_alloc_size = sizeof(struct sdhci_host), .platdata_auto_alloc_size = sizeof(struct sdhci_cdns_plat), - .ops = &sdhci_ops, + .ops = &sdhci_cdns_mmc_ops, };