drivers/mmcsd/mmcsd.h|mmcsd_sdio.c|mmcsd_sdio.h: support MMC high speed SDR mode

According to the eMMC specification, in Backwards Compatibility
with legacy MMC card mode, the frequency of the SD clock must be
0-26 MHZ; in high speed SDR mode, it must be 0-52MHZ. So we should
switch to high speed SDR mode if the clock frequency is higher than
26MHZ.

Signed-off-by: Yinzhe Wu <Yinzhe.Wu@sony.com>
Reviewed-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Jacky Cao <Jacky.Cao@sony.com>
Tested-by: Yinzhe Wu <Yinzhe.Wu@sony.com>

Author: Windrow14

drivers/mmcsd/mmcsd.h

@@ -81,7 +81,7 @@ struct mmcsd_state_s
   uint8_t dma:1;                   /* true: hardware supports DMA */
 #endif
 
-  uint8_t mode:2;                  /* (See MMCSDMODE_* definitions) */
+  uint8_t mode:4;                  /* (See MMCSDMODE_* definitions) */
   uint8_t type:4;                  /* Card type (See MMCSD_CARDTYPE_* definitions) */
   uint8_t buswidth:4;              /* Bus widths supported (SD only) */
   sdio_capset_t caps;              /* SDIO driver capabilities/limitations */

drivers/mmcsd/mmcsd_sdio.c

@@ -2583,6 +2583,20 @@ static int mmcsd_widebus(FAR struct mmcsd_state_s *priv)
 #ifdef CONFIG_MMCSD_MMCSUPPORT
   else
     {
+      if (priv->caps & SDIO_CAPS_MMC_HS_MODE)
+        {
+          mmcsd_sendcmdpoll(priv, MMCSD_CMD6,
+                            MMC_CMD6_HS_TIMING(EXT_CSD_HS_TIMING_HS));
+          ret = mmcsd_recv_r1(priv, MMCSD_CMD6);
+          if (ret != OK)
+            {
+              ferr("ERROR: (MMCSD_CMD6) Setting MMC speed mode: %d\n", ret);
+              return ret;
+            }
+
+          priv->mode = EXT_CSD_HS_TIMING_HS;
+        }
+
       SDIO_CLOCK(priv->dev, CLOCK_MMC_TRANSFER);
     }
 #endif /* #ifdef CONFIG_MMCSD_MMCSUPPORT */

drivers/mmcsd/mmcsd_sdio.h

@@ -59,6 +59,7 @@
 #define MMC_CMD6_MODE_WRITE_BYTE    (0x03)  /* Set target to value */
 
 #define EXT_CSD_BUS_WIDTH           183     /* WO */
+#define EXT_CSD_HS_TIMING           185     /* R/W */
 
 /* EXT_CSD_BUS_WIDTH */
 #define EXT_CSD_BUS_WIDTH_1         (0x00)  /* Card is in 1 bit mode */
@@ -71,6 +72,16 @@
                                      MMC_CMD6_INDEX(EXT_CSD_BUS_WIDTH) | \
                                      MMC_CMD6_MODE(MMC_CMD6_MODE_WRITE_BYTE))
 
+/* EXT_CSD_HS_TIMING */
+#define EXT_CSD_HS_TIMING_BC        0
+#define EXT_CSD_HS_TIMING_HS        1
+#define EXT_CSD_HS_TIMING_HS200     2
+#define EXT_CSD_HS_TIMING_HS400     3
+
+#define MMC_CMD6_HS_TIMING(timing)  (MMC_CMD6_VALUE(timing) | \
+                                     MMC_CMD6_INDEX(EXT_CSD_HS_TIMING) | \
+                                     MMC_CMD6_MODE(MMC_CMD6_MODE_WRITE_BYTE))
+
 /* CMD8 Argument:
  *    [31:12]: Reserved (shall be set to '0')
  *    [11:8]: Supply Voltage (VHS) 0x1 (Range: 2.7-3.6 V)

include/nuttx/sdio.h

@@ -479,6 +479,7 @@
 #define SDIO_CAPS_4BIT            0x08 /* Bit 3=1: Supports 4 bit operation */
 #define SDIO_CAPS_8BIT            0x10 /* Bit 4=1: Supports 8 bit operation */
 #define SDIO_CAPS_4BIT_ONLY       0x20 /* Bit 5=1: Supports 4-bit only operation */
+#define SDIO_CAPS_MMC_HS_MODE     0x40 /* Bit 6=1: Supports eMMC high speed mode */
 
 /****************************************************************************
  * Name: SDIO_STATUS