diff mbox

[06/12] mmc: sd: add support for uhs bus speed mode selection

Message ID 1297762510-2696-7-git-send-email-arindam.nath@amd.com (mailing list archive)
State New, archived
Headers show

Commit Message

Arindam Nath Feb. 15, 2011, 9:35 a.m. UTC
None
diff mbox

Patch

diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index 9e4574d..e681385 100644
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -464,6 +464,83 @@  static int sd_select_driver_type(struct mmc_card *card, u8 *status)
 	return 0;
 }
 
+static int sd_set_bus_speed_mode(struct mmc_card *card, u8 *status)
+{
+	unsigned int bus_speed, timing;
+	int err;
+
+	/*
+	 * If the host doesn't support any of the UHS-I modes, fallback on
+	 * default speed.
+	 */
+	if (!(card->host->caps & (MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR104 |
+	    MMC_CAP_UHS_DDR50)))
+		return 0;
+
+	if (card->host->caps & MMC_CAP_UHS_SDR104) {
+		if (card->sw_caps.uhs_bus_mode & SD_MODE_UHS_SDR104) {
+			bus_speed = UHS_SDR104_BUS_SPEED;
+			timing = MMC_TIMING_UHS_SDR104;
+			card->sw_caps.uhs_max_dtr = UHS_SDR104_MAX_DTR;
+		} else if (card->sw_caps.uhs_bus_mode & SD_MODE_UHS_SDR50) {
+			bus_speed = UHS_SDR50_BUS_SPEED;
+			timing = MMC_TIMING_UHS_SDR50;
+			card->sw_caps.uhs_max_dtr = UHS_SDR50_MAX_DTR;
+		} else if (card->sw_caps.uhs_bus_mode & SD_MODE_UHS_DDR50) {
+			bus_speed = UHS_DDR50_BUS_SPEED;
+			timing = MMC_TIMING_UHS_DDR50;
+			card->sw_caps.uhs_max_dtr = UHS_DDR50_MAX_DTR;
+		} else if (card->sw_caps.uhs_bus_mode & SD_MODE_UHS_SDR25) {
+			bus_speed = UHS_SDR25_BUS_SPEED;
+			timing = MMC_TIMING_UHS_SDR25;
+			card->sw_caps.uhs_max_dtr = UHS_SDR25_MAX_DTR;
+		}
+	} else if (card->host->caps & MMC_CAP_UHS_SDR50) {
+		if ((card->sw_caps.uhs_bus_mode & SD_MODE_UHS_SDR104) ||
+		    (card->sw_caps.uhs_bus_mode & SD_MODE_UHS_SDR50)) {
+			bus_speed = UHS_SDR50_BUS_SPEED;
+			timing = MMC_TIMING_UHS_SDR50;
+			card->sw_caps.uhs_max_dtr = UHS_SDR50_MAX_DTR;
+		} else if (card->sw_caps.uhs_bus_mode & SD_MODE_UHS_DDR50) {
+			bus_speed = UHS_DDR50_BUS_SPEED;
+			timing = MMC_TIMING_UHS_DDR50;
+			card->sw_caps.uhs_max_dtr = UHS_DDR50_MAX_DTR;
+		} else if (card->sw_caps.uhs_bus_mode & SD_MODE_UHS_SDR25) {
+			bus_speed = UHS_SDR25_BUS_SPEED;
+			timing = MMC_TIMING_UHS_SDR25;
+			card->sw_caps.uhs_max_dtr = UHS_SDR25_MAX_DTR;
+		}
+	} else if (card->host->caps & MMC_CAP_UHS_DDR50) {
+		if ((card->sw_caps.uhs_bus_mode & SD_MODE_UHS_SDR104) ||
+		    (card->sw_caps.uhs_bus_mode & SD_MODE_UHS_SDR50) ||
+		    (card->sw_caps.uhs_bus_mode & SD_MODE_UHS_DDR50)) {
+			bus_speed = UHS_DDR50_BUS_SPEED;
+			timing = MMC_TIMING_UHS_DDR50;
+			card->sw_caps.uhs_max_dtr = UHS_DDR50_MAX_DTR;
+		} else if (card->sw_caps.uhs_bus_mode & SD_MODE_UHS_SDR25) {
+			bus_speed = UHS_SDR25_BUS_SPEED;
+			timing = MMC_TIMING_UHS_SDR25;
+			card->sw_caps.uhs_max_dtr = UHS_SDR25_MAX_DTR;
+		}
+	}
+
+	err = mmc_sd_switch(card, 1, 0, bus_speed, status);
+	if (err)
+		return err;
+
+	if ((status[16] & 0xF) != bus_speed)
+		printk(KERN_WARNING "%s: Problem setting bus speed mode!\n",
+			mmc_hostname(card->host));
+	else {
+		if (bus_speed) {
+			mmc_set_timing(card->host, timing);
+			mmc_set_clock(card->host, card->sw_caps.uhs_max_dtr);
+		}
+	}
+
+	return 0;
+}
+
 /*
  * UHS-I specific initialization procedure
  */
@@ -499,6 +576,11 @@  static int mmc_sd_init_uhs_card(struct mmc_card *card)
 
 	/* Set the driver strength for the card */
 	err = sd_select_driver_type(card, status);
+	if (err)
+		goto out;
+
+	/* Set bus speed mode of the card */
+	err = sd_set_bus_speed_mode(card, status);
 
 out:
 	kfree(status);
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 5db0109..ae91c6b 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1281,7 +1281,13 @@  static void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 		ctrl &= ~SDHCI_CTRL_HISPD;
 
 	if (host->version >= SDHCI_SPEC_300) {
-		u16 ctrl_2;
+		u16 clk, ctrl_2;
+
+		/* In case of UHS-I modes, set High Speed Enable */
+		if ((ios->timing == MMC_TIMING_UHS_SDR50) ||
+		    (ios->timing == MMC_TIMING_UHS_SDR104) ||
+		    (ios->timing == MMC_TIMING_UHS_DDR50))
+			ctrl |= SDHCI_CTRL_HISPD;
 
 		ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
 		if (!(ctrl_2 & SDHCI_CTRL_PRESET_VAL_ENABLE)) {
@@ -1303,7 +1309,6 @@  static void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 			 * need to reset SD Clock Enable before changing High
 			 * Speed Enable to avoid generating clock gliches.
 			 */
-			u16 clk;
 
 			/* Reset SD Clock Enable */
 			clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
@@ -1316,6 +1321,29 @@  static void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 			clk |= SDHCI_CLOCK_CARD_EN;
 			sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
 		}
+
+		ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
+
+		/* Select Bus Speed Mode for host */
+		if (ios->timing == MMC_TIMING_UHS_SDR25)
+			ctrl_2 |= SDHCI_CTRL_UHS_SDR25;
+		else if (ios->timing == MMC_TIMING_UHS_SDR50)
+			ctrl_2 |= SDHCI_CTRL_UHS_SDR50;
+		else if (ios->timing == MMC_TIMING_UHS_SDR104)
+			ctrl_2 |= SDHCI_CTRL_UHS_SDR104;
+		else if (ios->timing == MMC_TIMING_UHS_DDR50)
+			ctrl_2 |= SDHCI_CTRL_UHS_DDR50;
+
+		/* Reset SD Clock Enable */
+		clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+		clk &= ~SDHCI_CLOCK_CARD_EN;
+		sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+
+		sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
+
+		/* Re-enable SD Clock */
+		clk |= SDHCI_CLOCK_CARD_EN;
+		sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
 	} else
 		sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL1);
 
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index a407b5b..5bf244d 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -150,6 +150,11 @@ 
 #define SDHCI_ACMD12_ERR	0x3C
 
 #define SDHCI_HOST_CONTROL2		0x3E
+#define  SDHCI_CTRL_UHS_SDR12		0x0000
+#define  SDHCI_CTRL_UHS_SDR25		0x0001
+#define  SDHCI_CTRL_UHS_SDR50		0x0002
+#define  SDHCI_CTRL_UHS_SDR104		0x0003
+#define  SDHCI_CTRL_UHS_DDR50		0x0004
 #define  SDHCI_CTRL_VDD_180		0x0008
 #define  SDHCI_CTRL_DRV_TYPE_B		0x0000
 #define  SDHCI_CTRL_DRV_TYPE_A		0x0010
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index 2d7f7a3..0b24c41 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -75,7 +75,23 @@  struct sd_ssr {
 
 struct sd_switch_caps {
 	unsigned int		hs_max_dtr;
+	unsigned int		uhs_max_dtr;
+#define UHS_SDR104_MAX_DTR	208000000
+#define UHS_SDR50_MAX_DTR	100000000
+#define UHS_DDR50_MAX_DTR	50000000
+#define UHS_SDR25_MAX_DTR	50000000
 	unsigned int		uhs_bus_mode;
+#define UHS_SDR12_BUS_SPEED	0
+#define UHS_SDR25_BUS_SPEED	1
+#define UHS_SDR50_BUS_SPEED	2
+#define UHS_SDR104_BUS_SPEED	3
+#define UHS_DDR50_BUS_SPEED	4
+
+#define SD_MODE_UHS_SDR12	(1 << UHS_SDR12_BUS_SPEED)
+#define SD_MODE_UHS_SDR25	(1 << UHS_SDR25_BUS_SPEED)
+#define SD_MODE_UHS_SDR50	(1 << UHS_SDR50_BUS_SPEED)
+#define SD_MODE_UHS_SDR104	(1 << UHS_SDR104_BUS_SPEED)
+#define SD_MODE_UHS_DDR50	(1 << UHS_DDR50_BUS_SPEED)
 	unsigned int		uhs_drv_type;
 #define SD_DRIVER_TYPE_B	0x01
 #define SD_DRIVER_TYPE_A	0x02
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index e6ae4c4..0a21839 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -50,6 +50,10 @@  struct mmc_ios {
 #define MMC_TIMING_LEGACY	0
 #define MMC_TIMING_MMC_HS	1
 #define MMC_TIMING_SD_HS	2
+#define MMC_TIMING_UHS_SDR25	MMC_TIMING_SD_HS
+#define MMC_TIMING_UHS_SDR50	3
+#define MMC_TIMING_UHS_SDR104	4
+#define MMC_TIMING_UHS_DDR50	5
 
 	unsigned char	ddr;			/* dual data rate used */