[U-Boot] [PATCH 5/7] mmc: uniphier-sd: Add Renesas SDR104/HS200 tuning support
Masahiro Yamada
yamada.masahiro at socionext.com
Thu Jan 25 10:42:30 UTC 2018
2018-01-17 2:17 GMT+09:00 Marek Vasut <marek.vasut at gmail.com>:
> Add code for PHY tuning required for SDR104/HS200 support on Renesas RCar.
>
> Signed-off-by: Marek Vasut <marek.vasut+renesas at gmail.com>
> Cc: Jaehoon Chung <jh80.chung at samsung.com>
> Cc: Masahiro Yamada <yamada.masahiro at socionext.com>
> ---
> drivers/mmc/uniphier-sd.c | 290 ++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 290 insertions(+)
>
> diff --git a/drivers/mmc/uniphier-sd.c b/drivers/mmc/uniphier-sd.c
> index d828535b11..2af8244515 100644
> --- a/drivers/mmc/uniphier-sd.c
> +++ b/drivers/mmc/uniphier-sd.c
> @@ -143,6 +143,10 @@ struct uniphier_sd_priv {
> #endif
> };
>
> +#if CONFIG_IS_ENABLED(MMC_HS200_SUPPORT)
> +static void uniphier_sd_reset_tuning(struct uniphier_sd_priv *priv);
> +#endif
> +
> static u64 uniphier_sd_readq(struct uniphier_sd_priv *priv, unsigned int reg)
> {
> if (priv->caps & UNIPHIER_SD_CAP_64BIT)
> @@ -596,6 +600,7 @@ 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;
> @@ -695,6 +700,7 @@ 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);
> }
> #endif
>
> @@ -720,6 +726,11 @@ static int uniphier_sd_set_ios(struct udevice *dev)
> uniphier_sd_set_clk_rate(priv, mmc);
> uniphier_sd_set_pins(dev);
>
> +#if CONFIG_IS_ENABLED(MMC_HS200_SUPPORT)
> + if (priv->caps & UNIPHIER_SD_CAP_RCAR_UHS)
> + uniphier_sd_reset_tuning(priv);
> +#endif
> +
> return 0;
> }
>
> @@ -734,10 +745,284 @@ static int uniphier_sd_get_cd(struct udevice *dev)
> UNIPHIER_SD_INFO1_CD);
> }
>
> +/*
> + * Renesas RCar SDR104 / HS200
> + */
> +#if CONFIG_IS_ENABLED(MMC_HS200_SUPPORT)
> +
> +/* 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;
> +}
> +#endif
> +
> 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,
> +#if CONFIG_IS_ENABLED(MMC_HS200_SUPPORT)
> + .execute_tuning = uniphier_sd_execute_tuning,
> +#endif
> };
>
> static void uniphier_sd_host_init(struct uniphier_sd_priv *priv)
> @@ -855,6 +1140,11 @@ static int uniphier_sd_probe(struct udevice *dev)
>
> upriv->mmc = &plat->mmc;
>
> +#if CONFIG_IS_ENABLED(MMC_HS200_SUPPORT)
> + if (priv->caps & UNIPHIER_SD_CAP_RCAR_UHS)
> + uniphier_sd_reset_tuning(priv);
> +#endif
> +
> return 0;
> }
>
> --
Honestly, I am terrified by this huge Renesas-specific code.
The HS200 support is Renesas's own extension.
Split the code into your file?
--
Best Regards
Masahiro Yamada
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