From 6900066cf67cb95503a922088eed4b31cccba8c2 Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Sat, 23 Nov 2019 13:36:23 +0100 Subject: [PATCH] mmc: tmio: sdhi: Add SCC error checking Check SCC for errors after check command if applicable and optionally adjust the bus skew settings accordingly. Signed-off-by: Marek Vasut Cc: Masahiro Yamada --- drivers/mmc/renesas-sdhi.c | 85 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 85 insertions(+) diff --git a/drivers/mmc/renesas-sdhi.c b/drivers/mmc/renesas-sdhi.c index 8c690a27b2..dcc77dd86c 100644 --- a/drivers/mmc/renesas-sdhi.c +++ b/drivers/mmc/renesas-sdhi.c @@ -34,7 +34,12 @@ #define RENESAS_SDHI_SCC_RVSCNTL_RVSEN BIT(0) #define RENESAS_SDHI_SCC_RVSREQ 0x814 #define RENESAS_SDHI_SCC_RVSREQ_RVSERR BIT(2) +#define RENESAS_SDHI_SCC_RVSREQ_REQTAPUP BIT(1) +#define RENESAS_SDHI_SCC_RVSREQ_REQTAPDOWN BIT(0) #define RENESAS_SDHI_SCC_SMPCMP 0x818 +#define RENESAS_SDHI_SCC_SMPCMP_CMD_ERR (BIT(24) | BIT(8)) +#define RENESAS_SDHI_SCC_SMPCMP_CMD_REQUP BIT(24) +#define RENESAS_SDHI_SCC_SMPCMP_CMD_REQDOWN BIT(8) #define RENESAS_SDHI_SCC_TMPPORT2 0x81c #define RENESAS_SDHI_SCC_TMPPORT2_HS400EN BIT(31) #define RENESAS_SDHI_SCC_TMPPORT2_HS400OSEL BIT(4) @@ -87,6 +92,84 @@ static void sd_scc_tmpport_write32(struct tmio_sd_priv *priv, u32 addr, u32 val) tmio_sd_writel(priv, 0, RENESAS_SDHI_SCC_TMPPORT4); } +static bool renesas_sdhi_check_scc_error(struct udevice *dev) +{ + struct tmio_sd_priv *priv = dev_get_priv(dev); + struct mmc *mmc = mmc_get_mmc_dev(dev); + unsigned long new_tap = priv->tap_set; + u32 reg, smpcmp; + + if ((priv->caps & TMIO_SD_CAP_RCAR_UHS) && + (mmc->selected_mode != UHS_SDR104) && + (mmc->selected_mode != MMC_HS_200) && + (mmc->selected_mode != MMC_HS_400) && + (priv->nrtaps != 4)) + return false; + + reg = tmio_sd_readl(priv, RENESAS_SDHI_SCC_RVSCNTL); + /* Handle automatic tuning correction */ + if (reg & RENESAS_SDHI_SCC_RVSCNTL_RVSEN) { + reg = tmio_sd_readl(priv, RENESAS_SDHI_SCC_RVSREQ); + if (reg & RENESAS_SDHI_SCC_RVSREQ_RVSERR) { + tmio_sd_writel(priv, 0, RENESAS_SDHI_SCC_RVSREQ); + return true; + } + + return false; + } + + /* Handle manual tuning correction */ + reg = tmio_sd_readl(priv, RENESAS_SDHI_SCC_RVSREQ); + if (!reg) /* No error */ + return false; + + tmio_sd_writel(priv, 0, RENESAS_SDHI_SCC_RVSREQ); + + if (mmc->selected_mode == MMC_HS_400) { + /* + * Correction Error Status contains CMD and DAT signal status. + * In HS400, DAT signal based on DS signal, not CLK. + * Therefore, use only CMD status. + */ + smpcmp = tmio_sd_readl(priv, RENESAS_SDHI_SCC_SMPCMP) & + RENESAS_SDHI_SCC_SMPCMP_CMD_ERR; + + switch (smpcmp) { + case 0: + return false; /* No error in CMD signal */ + case RENESAS_SDHI_SCC_SMPCMP_CMD_REQUP: + new_tap = (priv->tap_set + + priv->tap_num + 1) % priv->tap_num; + break; + case RENESAS_SDHI_SCC_SMPCMP_CMD_REQDOWN: + new_tap = (priv->tap_set + + priv->tap_num - 1) % priv->tap_num; + break; + default: + return true; /* Need re-tune */ + } + + priv->tap_set = new_tap; + } else { + if (reg & RENESAS_SDHI_SCC_RVSREQ_RVSERR) + return true; /* Need re-tune */ + else if (reg & RENESAS_SDHI_SCC_RVSREQ_REQTAPUP) + priv->tap_set = (priv->tap_set + + priv->tap_num + 1) % priv->tap_num; + else if (reg & RENESAS_SDHI_SCC_RVSREQ_REQTAPDOWN) + priv->tap_set = (priv->tap_set + + priv->tap_num - 1) % priv->tap_num; + else + return false; + } + + /* Set TAP position */ + tmio_sd_writel(priv, priv->tap_set >> ((priv->nrtaps == 4) ? 1 : 0), + RENESAS_SDHI_SCC_TAPSET); + + return false; +} + static void renesas_sdhi_adjust_hs400_mode_enable(struct tmio_sd_priv *priv) { u32 calib_code; @@ -536,6 +619,8 @@ static int renesas_sdhi_send_cmd(struct udevice *dev, struct mmc_cmd *cmd, CONFIG_IS_ENABLED(MMC_HS400_SUPPORT) struct tmio_sd_priv *priv = dev_get_priv(dev); + renesas_sdhi_check_scc_error(dev); + if (cmd->cmdidx == MMC_CMD_SEND_STATUS) renesas_sdhi_adjust_hs400_mode_enable(priv); #endif -- 2.39.5