Add code for PHY tuning required for SDR104/HS200 support on Renesas RCar.
Signed-off-by: Marek Vasut marek.vasut+renesas@gmail.com Cc: Jaehoon Chung jh80.chung@samsung.com Cc: Masahiro Yamada yamada.masahiro@socionext.com --- drivers/mmc/uniphier-sd.c | 280 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 280 insertions(+)
diff --git a/drivers/mmc/uniphier-sd.c b/drivers/mmc/uniphier-sd.c index 4456d0ed43..bb52315ec9 100644 --- a/drivers/mmc/uniphier-sd.c +++ b/drivers/mmc/uniphier-sd.c @@ -143,6 +143,8 @@ struct uniphier_sd_priv { #endif };
+static void uniphier_sd_reset_tuning(struct uniphier_sd_priv *priv); + static u64 uniphier_sd_readq(struct uniphier_sd_priv *priv, unsigned int reg) { if (priv->caps & UNIPHIER_SD_CAP_64BIT) @@ -596,6 +598,7 @@ static int uniphier_sd_set_bus_width(struct uniphier_sd_priv *priv, u32 val, tmp;
switch (mmc->bus_width) { + case 0: case 1: val = UNIPHIER_SD_OPTION_WIDTH_1; break; @@ -694,6 +697,7 @@ static void uniphier_sd_set_pins(struct udevice *dev) regulator_set_value(priv->vqmmc_dev, 1800000); else regulator_set_value(priv->vqmmc_dev, 3300000); + regulator_set_enable(priv->vqmmc_dev, true); }
if (mmc->signal_voltage == MMC_SIGNAL_VOLTAGE_180) @@ -718,6 +722,9 @@ static int uniphier_sd_set_ios(struct udevice *dev) uniphier_sd_set_clk_rate(priv, mmc); uniphier_sd_set_pins(dev);
+ if (priv->caps & UNIPHIER_SD_CAP_RCAR_UHS) + uniphier_sd_reset_tuning(priv); + return 0; }
@@ -732,10 +739,280 @@ static int uniphier_sd_get_cd(struct udevice *dev) UNIPHIER_SD_INFO1_CD); }
+/* + * Renesas RCar SDR104 / HS200 + */ + +/* SCC registers */ +#define SH_MOBILE_SDHI_SCC_DTCNTL 0x800 +#define SH_MOBILE_SDHI_SCC_DTCNTL_TAPEN BIT(0) +#define SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT 16 +#define SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_MASK 0xff +#define SH_MOBILE_SDHI_SCC_TAPSET 0x804 +#define SH_MOBILE_SDHI_SCC_DT2FF 0x808 +#define SH_MOBILE_SDHI_SCC_CKSEL 0x80c +#define SH_MOBILE_SDHI_SCC_CKSEL_DTSEL BIT(0) +#define SH_MOBILE_SDHI_SCC_RVSCNTL 0x810 +#define SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN BIT(0) +#define SH_MOBILE_SDHI_SCC_RVSREQ 0x814 +#define SH_MOBILE_SDHI_SCC_RVSREQ_RVSERR BIT(2) +#define SH_MOBILE_SDHI_SCC_SMPCMP 0x818 +#define SH_MOBILE_SDHI_SCC_TMPPORT2 0x81c + +#define SH_MOBILE_SDHI_MAX_TAP 3 + +static unsigned int uniphier_sd_init_tuning(struct uniphier_sd_priv *priv) +{ + u32 reg; + + /* Initialize SCC */ + uniphier_sd_writel(priv, 0, UNIPHIER_SD_INFO1); + + reg = uniphier_sd_readl(priv, UNIPHIER_SD_CLKCTL); + reg &= ~UNIPHIER_SD_CLKCTL_SCLKEN; + uniphier_sd_writel(priv, reg, UNIPHIER_SD_CLKCTL); + + /* Set sampling clock selection range */ + uniphier_sd_writel(priv, 0x8 << SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT, + SH_MOBILE_SDHI_SCC_DTCNTL); + + reg = uniphier_sd_readl(priv, SH_MOBILE_SDHI_SCC_DTCNTL); + reg |= SH_MOBILE_SDHI_SCC_DTCNTL_TAPEN; + uniphier_sd_writel(priv, reg, SH_MOBILE_SDHI_SCC_DTCNTL); + + reg = uniphier_sd_readl(priv, SH_MOBILE_SDHI_SCC_CKSEL); + reg |= SH_MOBILE_SDHI_SCC_CKSEL_DTSEL; + uniphier_sd_writel(priv, reg, SH_MOBILE_SDHI_SCC_CKSEL); + + reg = uniphier_sd_readl(priv, SH_MOBILE_SDHI_SCC_RVSCNTL); + reg &= ~SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN; + uniphier_sd_writel(priv, reg, SH_MOBILE_SDHI_SCC_RVSCNTL); + + uniphier_sd_writel(priv, 0x300 /* scc_tappos */, + SH_MOBILE_SDHI_SCC_DT2FF); + + reg = uniphier_sd_readl(priv, UNIPHIER_SD_CLKCTL); + reg |= UNIPHIER_SD_CLKCTL_SCLKEN; + uniphier_sd_writel(priv, reg, UNIPHIER_SD_CLKCTL); + + /* Read TAPNUM */ + return (uniphier_sd_readl(priv, SH_MOBILE_SDHI_SCC_DTCNTL) >> + SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT) & + SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_MASK; +} + +static void uniphier_sd_reset_tuning(struct uniphier_sd_priv *priv) +{ + u32 reg; + + /* Reset SCC */ + reg = uniphier_sd_readl(priv, UNIPHIER_SD_CLKCTL); + reg &= ~UNIPHIER_SD_CLKCTL_SCLKEN; + uniphier_sd_writel(priv, reg, UNIPHIER_SD_CLKCTL); + + reg = uniphier_sd_readl(priv, SH_MOBILE_SDHI_SCC_CKSEL); + reg &= ~SH_MOBILE_SDHI_SCC_CKSEL_DTSEL; + uniphier_sd_writel(priv, reg, SH_MOBILE_SDHI_SCC_CKSEL); + + reg = uniphier_sd_readl(priv, UNIPHIER_SD_CLKCTL); + reg |= UNIPHIER_SD_CLKCTL_SCLKEN; + uniphier_sd_writel(priv, reg, UNIPHIER_SD_CLKCTL); + + reg = uniphier_sd_readl(priv, SH_MOBILE_SDHI_SCC_RVSCNTL); + reg &= ~SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN; + uniphier_sd_writel(priv, reg, SH_MOBILE_SDHI_SCC_RVSCNTL); + + reg = uniphier_sd_readl(priv, SH_MOBILE_SDHI_SCC_RVSCNTL); + reg &= ~SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN; + uniphier_sd_writel(priv, reg, SH_MOBILE_SDHI_SCC_RVSCNTL); +} + +static void uniphier_sd_prepare_tuning(struct uniphier_sd_priv *priv, + unsigned long tap) +{ + /* Set sampling clock position */ + uniphier_sd_writel(priv, tap, SH_MOBILE_SDHI_SCC_TAPSET); +} + +static unsigned int sh_mobile_sdhi_compare_scc_data(struct uniphier_sd_priv *priv) +{ + /* Get comparison of sampling data */ + return uniphier_sd_readl(priv, SH_MOBILE_SDHI_SCC_SMPCMP); +} + +static int uniphier_sd_select_tuning(struct uniphier_sd_priv *priv, + unsigned int tap_num, unsigned int taps, + unsigned int smpcmp) +{ + unsigned long tap_cnt; /* counter of tuning success */ + unsigned long tap_set; /* tap position */ + unsigned long tap_start;/* start position of tuning success */ + unsigned long tap_end; /* end position of tuning success */ + unsigned long ntap; /* temporary counter of tuning success */ + unsigned long match_cnt;/* counter of matching data */ + unsigned long i; + bool select = false; + u32 reg; + + /* Clear SCC_RVSREQ */ + uniphier_sd_writel(priv, 0, SH_MOBILE_SDHI_SCC_RVSREQ); + + /* Merge the results */ + for (i = 0; i < tap_num * 2; i++) { + if (!(taps & BIT(i))) { + taps &= ~BIT(i % tap_num); + taps &= ~BIT((i % tap_num) + tap_num); + } + if (!(smpcmp & BIT(i))) { + smpcmp &= ~BIT(i % tap_num); + smpcmp &= ~BIT((i % tap_num) + tap_num); + } + } + + /* + * Find the longest consecutive run of successful probes. If that + * is more than SH_MOBILE_SDHI_MAX_TAP probes long then use the + * center index as the tap. + */ + tap_cnt = 0; + ntap = 0; + tap_start = 0; + tap_end = 0; + for (i = 0; i < tap_num * 2; i++) { + if (taps & BIT(i)) + ntap++; + else { + if (ntap > tap_cnt) { + tap_start = i - ntap; + tap_end = i - 1; + tap_cnt = ntap; + } + ntap = 0; + } + } + + if (ntap > tap_cnt) { + tap_start = i - ntap; + tap_end = i - 1; + tap_cnt = ntap; + } + + /* + * If all of the TAP is OK, the sampling clock position is selected by + * identifying the change point of data. + */ + if (tap_cnt == tap_num * 2) { + match_cnt = 0; + ntap = 0; + tap_start = 0; + tap_end = 0; + for (i = 0; i < tap_num * 2; i++) { + if (smpcmp & BIT(i)) + ntap++; + else { + if (ntap > match_cnt) { + tap_start = i - ntap; + tap_end = i - 1; + match_cnt = ntap; + } + ntap = 0; + } + } + if (ntap > match_cnt) { + tap_start = i - ntap; + tap_end = i - 1; + match_cnt = ntap; + } + if (match_cnt) + select = true; + } else if (tap_cnt >= SH_MOBILE_SDHI_MAX_TAP) + select = true; + + if (select) + tap_set = ((tap_start + tap_end) / 2) % tap_num; + else + return -EIO; + + /* Set SCC */ + uniphier_sd_writel(priv, tap_set, SH_MOBILE_SDHI_SCC_TAPSET); + + /* Enable auto re-tuning */ + reg = uniphier_sd_readl(priv, SH_MOBILE_SDHI_SCC_RVSCNTL); + reg |= SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN; + uniphier_sd_writel(priv, reg, SH_MOBILE_SDHI_SCC_RVSCNTL); + + return 0; +} + +static int uniphier_sd_execute_tuning(struct udevice *dev, uint opcode) +{ + struct uniphier_sd_priv *priv = dev_get_priv(dev); + struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev); + struct mmc *mmc = upriv->mmc; + unsigned int tap_num; + unsigned int taps = 0, smpcmp = 0; + int i, ret = 0; + u32 caps; + + /* Only supported on Renesas RCar */ + if (!(priv->caps & UNIPHIER_SD_CAP_RCAR_UHS)) + return -EINVAL; + + /* clock tuning is not needed for upto 52MHz */ + if (!((mmc->selected_mode == MMC_HS_200) || + (mmc->selected_mode == UHS_SDR104) || + (mmc->selected_mode == UHS_SDR50))) + return 0; + + tap_num = uniphier_sd_init_tuning(priv); + if (!tap_num) + /* Tuning is not supported */ + goto out; + + if (tap_num * 2 >= sizeof(taps) * 8) { + dev_err(dev, + "Too many taps, skipping tuning. Please consider updating size of taps field of tmio_mmc_host\n"); + goto out; + } + + /* Issue CMD19 twice for each tap */ + for (i = 0; i < 2 * tap_num; i++) { + uniphier_sd_prepare_tuning(priv, i % tap_num); + + /* Force PIO for the tuning */ + caps = priv->caps; + priv->caps &= ~UNIPHIER_SD_CAP_DMA_INTERNAL; + + ret = mmc_send_tuning(mmc, opcode, NULL); + + priv->caps = caps; + + if (ret == 0) + taps |= BIT(i); + + ret = sh_mobile_sdhi_compare_scc_data(priv); + if (ret == 0) + smpcmp |= BIT(i); + + mdelay(1); + } + + ret = uniphier_sd_select_tuning(priv, tap_num, taps, smpcmp); + +out: + if (ret < 0) { + dev_warn(dev, "Tuning procedure failed\n"); + uniphier_sd_reset_tuning(priv); + } + + return ret; +} + static const struct dm_mmc_ops uniphier_sd_ops = { .send_cmd = uniphier_sd_send_cmd, .set_ios = uniphier_sd_set_ios, .get_cd = uniphier_sd_get_cd, + .execute_tuning = uniphier_sd_execute_tuning, };
static void uniphier_sd_host_init(struct uniphier_sd_priv *priv) @@ -852,6 +1129,9 @@ static int uniphier_sd_probe(struct udevice *dev)
upriv->mmc = &plat->mmc;
+ if (priv->caps & UNIPHIER_SD_CAP_RCAR_UHS) + uniphier_sd_reset_tuning(priv); + return 0; }