On RK3399, a register bit must be set to enable Enhanced Strobe. Let the Rockchip SDHCI driver set it when Enhanced Strobe configuration is requested. However, having it set makes the lower-speed modes stop working and makes reinitialization fail, so let it be unset as needed in set_control_reg().
This is mostly ported from Linux's Arasan SDHCI driver which happens to be the underlying IP. (drivers/mmc/host/sdhci-of-arasan.c in Linux tree).
Signed-off-by: Alper Nebi Yasak alpernebiyasak@gmail.com ---
Changes in v4: - Add comment for Rockchip SDHCI set_enhanced_strobe() driver data op
Changes in v2: - Unset ES bit in rk3399 set_control_reg() to fix a reinit issue - Don't use unnecessary & for function pointer in ops struct - Rename rk3399_set_enhanced_strobe -> rk3399_sdhci_set_enhanced_strobe - Let set_enhanced_strobe() unset the ES bit if mode is not HS400_ES
drivers/mmc/rockchip_sdhci.c | 53 ++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+)
diff --git a/drivers/mmc/rockchip_sdhci.c b/drivers/mmc/rockchip_sdhci.c index b91df05de4ff..f4d5a59036a2 100644 --- a/drivers/mmc/rockchip_sdhci.c +++ b/drivers/mmc/rockchip_sdhci.c @@ -42,6 +42,9 @@ ((((x) >> PHYCTRL_DLLRDY_SHIFT) & PHYCTRL_DLLRDY_MASK) ==\ PHYCTRL_DLLRDY_DONE)
+#define ARASAN_VENDOR_REGISTER 0x78 +#define ARASAN_VENDOR_ENHANCED_STROBE BIT(0) + /* Rockchip specific Registers */ #define DWCMSHC_EMMC_DLL_CTRL 0x800 #define DWCMSHC_EMMC_DLL_CTRL_RESET BIT(1) @@ -117,6 +120,19 @@ struct sdhci_data { * Return: 0 if successful, -ve on error */ int (*set_ios_post)(struct sdhci_host *host); + + /** + * set_enhanced_strobe() - Set HS400 Enhanced Strobe config + * + * This is the set_enhanced_strobe() SDHCI operation that should + * be used for the hardware this driver data is associated with. + * Normally, this is used to set any host-specific configuration + * necessary for HS400 ES. + * + * @host: SDHCI host structure + * Return: 0 if successful, -ve on error + */ + int (*set_enhanced_strobe)(struct sdhci_host *host); };
static int rk3399_emmc_phy_init(struct udevice *dev) @@ -206,6 +222,21 @@ static int rk3399_emmc_get_phy(struct udevice *dev) return 0; }
+static int rk3399_sdhci_set_enhanced_strobe(struct sdhci_host *host) +{ + struct mmc *mmc = host->mmc; + u32 vendor; + + vendor = sdhci_readl(host, ARASAN_VENDOR_REGISTER); + if (mmc->selected_mode == MMC_HS_400_ES) + vendor |= ARASAN_VENDOR_ENHANCED_STROBE; + else + vendor &= ~ARASAN_VENDOR_ENHANCED_STROBE; + sdhci_writel(host, vendor, ARASAN_VENDOR_REGISTER); + + return 0; +} + static void rk3399_sdhci_set_control_reg(struct sdhci_host *host) { struct rockchip_sdhc *priv = container_of(host, struct rockchip_sdhc, host); @@ -217,6 +248,15 @@ static void rk3399_sdhci_set_control_reg(struct sdhci_host *host) rk3399_emmc_phy_power_off(priv->phy);
sdhci_set_control_reg(host); + + /* + * Reinitializing the device tries to set it to lower-speed modes + * first, which fails if the Enhanced Strobe bit is set, making + * the device impossible to use. Set the correct value here to + * let reinitialization attempts succeed. + */ + if (CONFIG_IS_ENABLED(MMC_HS400_ES_SUPPORT)) + rk3399_sdhci_set_enhanced_strobe(host); };
static int rk3399_sdhci_set_ios_post(struct sdhci_host *host) @@ -409,10 +449,22 @@ static int rockchip_sdhci_execute_tuning(struct mmc *mmc, u8 opcode) return ret; }
+static int rockchip_sdhci_set_enhanced_strobe(struct sdhci_host *host) +{ + struct rockchip_sdhc *priv = container_of(host, struct rockchip_sdhc, host); + struct sdhci_data *data = (struct sdhci_data *)dev_get_driver_data(priv->dev); + + if (data->set_enhanced_strobe) + return data->set_enhanced_strobe(host); + + return -ENOTSUPP; +} + static struct sdhci_ops rockchip_sdhci_ops = { .set_ios_post = rockchip_sdhci_set_ios_post, .platform_execute_tuning = &rockchip_sdhci_execute_tuning, .set_control_reg = rockchip_sdhci_set_control_reg, + .set_enhanced_strobe = rockchip_sdhci_set_enhanced_strobe, };
static int rockchip_sdhci_probe(struct udevice *dev) @@ -495,6 +547,7 @@ static const struct sdhci_data rk3399_data = { .emmc_phy_init = rk3399_emmc_phy_init, .set_control_reg = rk3399_sdhci_set_control_reg, .set_ios_post = rk3399_sdhci_set_ios_post, + .set_enhanced_strobe = rk3399_sdhci_set_enhanced_strobe, };
static const struct sdhci_data rk3568_data = {