mmc: support hs400 enhanced strobe mode

eMMC 5.1+ supports HS400 Enhances Strobe mode without the need for
tuning procedure.
The flow is as following:
 - set HS_TIMIMG (Highspeed)
 - Host change freq to <= 52Mhz
 - set the bus width to Enhanced strobe and DDR8Bit(CMD6),
   EXT_CSD[183] = 0x86 instead of 0x80
 - set HS_TIMING to 0x3 (HS400)
 - Host change freq to <= 200Mhz
 - Host select HS400 enhanced strobe complete

Signed-off-by: Peng Fan <peng.fan@nxp.com>

diff --git a/drivers/mmc/Kconfig b/drivers/mmc/Kconfig
index a4a6a6c085d7f459aa94d3b930f0517aefadfd15..890ef358a004aa56c93f7abe26e195a17dbe2a10 100644 (file)
--- a/drivers/mmc/Kconfig
+++ b/drivers/mmc/Kconfig
@@ -135,6 +135,18 @@ config SPL_MMC_UHS_SUPPORT
          cards. The IO voltage must be switchable from 3.3v to 1.8v. The bus
          frequency can go up to 208MHz (SDR104)
 
+config MMC_HS400_ES_SUPPORT
+       bool "enable HS400 Enhanced Strobe support"
+       help
+         The HS400 Enhanced Strobe mode is support by some eMMC. The bus
+         frequency is up to 200MHz. This mode does not tune the IO.
+
+config SPL_MMC_HS400_ES_SUPPORT
+       bool "enable HS400 Enhanced Strobe support in SPL"
+       help
+         The HS400 Enhanced Strobe mode is support by some eMMC. The bus
+         frequency is up to 200MHz. This mode does not tune the IO.
+
 config MMC_HS400_SUPPORT
        bool "enable HS400 support"
        select MMC_HS200_SUPPORT

diff --git a/drivers/mmc/mmc-uclass.c b/drivers/mmc/mmc-uclass.c
index 9327c8302de6b3fd922a3dea2b4f4df05cbcb01d..8bf63bbd9caba6d09e93e13cba01027f3dc0994a 100644 (file)
--- a/drivers/mmc/mmc-uclass.c
+++ b/drivers/mmc/mmc-uclass.c
@@ -105,6 +105,23 @@ int mmc_execute_tuning(struct mmc *mmc, uint opcode)
 }
 #endif
 
+#if CONFIG_IS_ENABLED(MMC_HS400_ES_SUPPORT)
+int dm_mmc_set_enhanced_strobe(struct udevice *dev)
+{
+       struct dm_mmc_ops *ops = mmc_get_ops(dev);
+
+       if (ops->set_enhanced_strobe)
+               return ops->set_enhanced_strobe(dev);
+
+       return -ENOTSUPP;
+}
+
+int mmc_set_enhanced_strobe(struct mmc *mmc)
+{
+       return dm_mmc_set_enhanced_strobe(mmc->dev);
+}
+#endif
+
 int mmc_of_parse(struct udevice *dev, struct mmc_config *cfg)
 {
        int val;

diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 2a1ba6e51dc9cbf7a5c91f7a64bf298e2ca9691b..c9aa13b409ac9d4a6ff7b63af4ac86646aa7e44c 100644 (file)
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -148,6 +148,7 @@ const char *mmc_mode_name(enum bus_mode mode)
              [MMC_DDR_52]      = "MMC DDR52 (52MHz)",
              [MMC_HS_200]      = "HS200 (200MHz)",
              [MMC_HS_400]      = "HS400 (200MHz)",
+             [MMC_HS_400_ES]   = "HS400ES (200MHz)",
        };
 
        if (mode >= MMC_MODES_END)
@@ -173,6 +174,7 @@ static uint mmc_mode2freq(struct mmc *mmc, enum bus_mode mode)
              [UHS_SDR104]      = 208000000,
              [MMC_HS_200]      = 200000000,
              [MMC_HS_400]      = 200000000,
+             [MMC_HS_400_ES]   = 200000000,
        };
 
        if (mode == MMC_LEGACY)
@@ -838,6 +840,11 @@ static int mmc_set_card_speed(struct mmc *mmc, enum bus_mode mode,
        case MMC_HS_400:
                speed_bits = EXT_CSD_TIMING_HS400;
                break;
+#endif
+#if CONFIG_IS_ENABLED(MMC_HS400_ES_SUPPORT)
+       case MMC_HS_400_ES:
+               speed_bits = EXT_CSD_TIMING_HS400;
+               break;
 #endif
        case MMC_LEGACY:
                speed_bits = EXT_CSD_TIMING_LEGACY;
@@ -909,7 +916,8 @@ static int mmc_get_capabilities(struct mmc *mmc)
                mmc->card_caps |= MMC_MODE_HS200;
        }
 #endif
-#if CONFIG_IS_ENABLED(MMC_HS400_SUPPORT)
+#if CONFIG_IS_ENABLED(MMC_HS400_SUPPORT) || \
+       CONFIG_IS_ENABLED(MMC_HS400_ES_SUPPORT)
        if (cardtype & (EXT_CSD_CARD_TYPE_HS400_1_2V |
                        EXT_CSD_CARD_TYPE_HS400_1_8V)) {
                mmc->card_caps |= MMC_MODE_HS400;
@@ -923,6 +931,13 @@ static int mmc_get_capabilities(struct mmc *mmc)
        if (cardtype & EXT_CSD_CARD_TYPE_26)
                mmc->card_caps |= MMC_MODE_HS;
 
+#if CONFIG_IS_ENABLED(MMC_HS400_ES_SUPPORT)
+       if (ext_csd[EXT_CSD_STROBE_SUPPORT] &&
+           (mmc->card_caps & MMC_MODE_HS400)) {
+               mmc->card_caps |= MMC_MODE_HS400_ES;
+       }
+#endif
+
        return 0;
 }
 #endif
@@ -1799,6 +1814,7 @@ static int mmc_set_lowest_voltage(struct mmc *mmc, enum bus_mode mode,
        u32 card_mask = 0;
 
        switch (mode) {
+       case MMC_HS_400_ES:
        case MMC_HS_400:
        case MMC_HS_200:
                if (mmc->cardtype & (EXT_CSD_CARD_TYPE_HS200_1_8V |
@@ -1841,6 +1857,12 @@ static inline int mmc_set_lowest_voltage(struct mmc *mmc, enum bus_mode mode,
 #endif
 
 static const struct mode_width_tuning mmc_modes_by_pref[] = {
+#if CONFIG_IS_ENABLED(MMC_HS400_ES_SUPPORT)
+       {
+               .mode = MMC_HS_400_ES,
+               .widths = MMC_MODE_8BIT,
+       },
+#endif
 #if CONFIG_IS_ENABLED(MMC_HS400_SUPPORT)
        {
                .mode = MMC_HS_400,
@@ -1938,6 +1960,47 @@ static int mmc_select_hs400(struct mmc *mmc)
 }
 #endif
 
+#if CONFIG_IS_ENABLED(MMC_HS400_ES_SUPPORT)
+#if !CONFIG_IS_ENABLED(DM_MMC)
+static int mmc_set_enhanced_strobe(struct mmc *mmc)
+{
+       return -ENOTSUPP;
+}
+#endif
+static int mmc_select_hs400es(struct mmc *mmc)
+{
+       int err;
+
+       err = mmc_set_card_speed(mmc, MMC_HS, true);
+       if (err)
+               return err;
+
+       err = mmc_switch(mmc, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_BUS_WIDTH,
+                        EXT_CSD_BUS_WIDTH_8 | EXT_CSD_DDR_FLAG |
+                        EXT_CSD_BUS_WIDTH_STROBE);
+       if (err) {
+               printf("switch to bus width for hs400 failed\n");
+               return err;
+       }
+       /* TODO: driver strength */
+       err = mmc_set_card_speed(mmc, MMC_HS_400_ES, false);
+       if (err)
+               return err;
+
+       mmc_select_mode(mmc, MMC_HS_400_ES);
+       err = mmc_set_clock(mmc, mmc->tran_speed, false);
+       if (err)
+               return err;
+
+       return mmc_set_enhanced_strobe(mmc);
+}
+#else
+static int mmc_select_hs400es(struct mmc *mmc)
+{
+       return -ENOTSUPP;
+}
+#endif
+
 #define for_each_supported_width(caps, ddr, ecbv) \
        for (ecbv = ext_csd_bus_width;\
            ecbv < ext_csd_bus_width + ARRAY_SIZE(ext_csd_bus_width);\
@@ -2016,6 +2079,13 @@ static int mmc_select_mode_and_width(struct mmc *mmc, uint card_caps)
                                        printf("Select HS400 failed %d\n", err);
                                        goto error;
                                }
+                       } else if (mwt->mode == MMC_HS_400_ES) {
+                               err = mmc_select_hs400es(mmc);
+                               if (err) {
+                                       printf("Select HS400ES failed %d\n",
+                                              err);
+                                       goto error;
+                               }
                        } else {
                                /* configure the bus speed (card) */
                                err = mmc_set_card_speed(mmc, mwt->mode, false);

diff --git a/include/mmc.h b/include/mmc.h
index 0ef891f5c26e01f0422517f1738399f9d42ac709..46422f41a484087e6909163444973d2b6b94a2e9 100644 (file)
--- a/include/mmc.h
+++ b/include/mmc.h
@@ -65,6 +65,7 @@
 #define MMC_MODE_DDR_52MHz     MMC_CAP(MMC_DDR_52)
 #define MMC_MODE_HS200         MMC_CAP(MMC_HS_200)
 #define MMC_MODE_HS400         MMC_CAP(MMC_HS_400)
+#define MMC_MODE_HS400_ES      MMC_CAP(MMC_HS_400_ES)
 
 #define MMC_CAP_NONREMOVABLE   BIT(14)
 #define MMC_CAP_NEEDS_POLL     BIT(15)
@@ -223,6 +224,7 @@ static inline bool mmc_is_tuning_cmd(uint cmdidx)
 #define EXT_CSD_BOOT_BUS_WIDTH         177
 #define EXT_CSD_PART_CONF              179     /* R/W */
 #define EXT_CSD_BUS_WIDTH              183     /* R/W */
+#define EXT_CSD_STROBE_SUPPORT         184     /* R/W */
 #define EXT_CSD_HS_TIMING              185     /* R/W */
 #define EXT_CSD_REV                    192     /* RO */
 #define EXT_CSD_CARD_TYPE              196     /* RO */
@@ -266,11 +268,13 @@ static inline bool mmc_is_tuning_cmd(uint cmdidx)
 #define EXT_CSD_DDR_BUS_WIDTH_4        5       /* Card is in 4 bit DDR mode */
 #define EXT_CSD_DDR_BUS_WIDTH_8        6       /* Card is in 8 bit DDR mode */
 #define EXT_CSD_DDR_FLAG       BIT(2)  /* Flag for DDR mode */
+#define EXT_CSD_BUS_WIDTH_STROBE BIT(7)        /* Enhanced strobe mode */
 
 #define EXT_CSD_TIMING_LEGACY  0       /* no high speed */
 #define EXT_CSD_TIMING_HS      1       /* HS */
 #define EXT_CSD_TIMING_HS200   2       /* HS200 */
 #define EXT_CSD_TIMING_HS400   3       /* HS400 */
+#define EXT_CSD_DRV_STR_SHIFT  4       /* Driver Strength shift */
 
 #define EXT_CSD_BOOT_ACK_ENABLE                        (1 << 6)
 #define EXT_CSD_BOOT_PARTITION_ENABLE          (1 << 3)
@@ -457,6 +461,11 @@ struct dm_mmc_ops {
         * @return 0 if dat0 is in the target state, -ve on error
         */
        int (*wait_dat0)(struct udevice *dev, int state, int timeout);
+
+#if CONFIG_IS_ENABLED(MMC_HS400_ES_SUPPORT)
+       /* set_enhanced_strobe() - set HS400 enhanced strobe */
+       int (*set_enhanced_strobe)(struct udevice *dev);
+#endif
 };
 
 #define mmc_get_ops(dev)        ((struct dm_mmc_ops *)(dev)->driver->ops)
@@ -475,6 +484,7 @@ int mmc_getcd(struct mmc *mmc);
 int mmc_getwp(struct mmc *mmc);
 int mmc_execute_tuning(struct mmc *mmc, uint opcode);
 int mmc_wait_dat0(struct mmc *mmc, int state, int timeout);
+int mmc_set_enhanced_strobe(struct mmc *mmc);
 
 #else
 struct mmc_ops {
@@ -520,6 +530,7 @@ enum bus_mode {
        UHS_SDR104,
        MMC_HS_200,
        MMC_HS_400,
+       MMC_HS_400_ES,
        MMC_MODES_END
 };
 
@@ -537,6 +548,10 @@ static inline bool mmc_is_mode_ddr(enum bus_mode mode)
 #if CONFIG_IS_ENABLED(MMC_HS400_SUPPORT)
        else if (mode == MMC_HS_400)
                return true;
+#endif
+#if CONFIG_IS_ENABLED(MMC_HS400_ES_SUPPORT)
+       else if (mode == MMC_HS_400_ES)
+               return true;
 #endif
        else
                return false;