[U-Boot] [PATCH 20/22] mmc: Add support for UHS modes
Jean-Jacques Hiblot
jjhiblot at ti.com
Fri May 12 18:16:38 UTC 2017
Add UHS modes to the list of supported modes, get the UHS capabilites of
the SDcard and implement the procedure to switch the voltage (UHS modes
use 1v8 IO lines)
During the voltage switch procedure, DAT0 is used by the card to signal
when it's ready. The optional card_busy() callback can be used to get this
information from the host driver.
Signed-off-by: Jean-Jacques Hiblot <jjhiblot at ti.com>
---
drivers/mmc/mmc.c | 169 +++++++++++++++++++++++++++++++++++++++++++++++++++---
include/mmc.h | 27 ++++++++-
2 files changed, 188 insertions(+), 8 deletions(-)
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index f6509f1..074d286 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -31,6 +31,7 @@ static const unsigned int sd_au_size[] = {
};
static int mmc_set_signal_voltage(struct mmc *mmc, uint signal_voltage);
static void mmc_power_cycle(struct mmc *mmc);
+static int mmc_card_busy(struct mmc *mmc);
#if CONFIG_IS_ENABLED(MMC_TINY)
static struct mmc mmc_static;
@@ -403,7 +404,68 @@ static int mmc_go_idle(struct mmc *mmc)
return 0;
}
-static int sd_send_op_cond(struct mmc *mmc)
+static int mmc_switch_voltage(struct mmc *mmc, int signal_voltage)
+{
+ struct mmc_cmd cmd;
+ int err = 0;
+
+ /*
+ * Send CMD11 only if the request is to switch the card to
+ * 1.8V signalling.
+ */
+ if (signal_voltage == MMC_SIGNAL_VOLTAGE_330)
+ return mmc_set_signal_voltage(mmc, signal_voltage);
+
+ cmd.cmdidx = SD_CMD_SWITCH_UHS18V;
+ cmd.cmdarg = 0;
+ cmd.resp_type = MMC_RSP_R1;
+
+ err = mmc_send_cmd(mmc, &cmd, NULL);
+ if (err)
+ goto fail;
+
+ if (!mmc_host_is_spi(host) && (cmd.response[0] & MMC_STATUS_ERROR))
+ goto fail;
+
+ /*
+ * The card should drive cmd and dat[0:3] low immediately
+ * after the response of cmd11, but wait 1 ms to be sure
+ */
+ udelay(1000);
+ if (mmc_card_busy(mmc))
+ goto fail;
+
+ /*
+ * During a signal voltage level switch, the clock must be gated
+ * for 5 ms according to the SD spec
+ */
+ mmc_set_clock(mmc, mmc->clock, true);
+
+ err = mmc_set_signal_voltage(mmc, signal_voltage);
+ if (err)
+ goto fail;
+
+ /* Keep clock gated for at least 10 ms, though spec only says 5 ms */
+ udelay(10000);
+ mmc_set_clock(mmc, mmc->clock, false);
+
+ /* Wait for at least 1 ms according to spec */
+ udelay(1000);
+
+ /*
+ * Failure to switch is indicated by the card holding
+ * dat[0:3] low
+ */
+ if (mmc_card_busy(mmc))
+ goto fail;
+
+ return 0;
+
+fail:
+ return -EIO;
+}
+
+static int sd_send_op_cond(struct mmc *mmc, bool uhs_en)
{
int timeout = 1000;
int err;
@@ -435,6 +497,9 @@ static int sd_send_op_cond(struct mmc *mmc)
if (mmc->version == SD_VERSION_2)
cmd.cmdarg |= OCR_HCS;
+ if (uhs_en)
+ cmd.cmdarg |= OCR_S18R;
+
err = mmc_send_cmd(mmc, &cmd, NULL);
if (err)
@@ -465,6 +530,13 @@ static int sd_send_op_cond(struct mmc *mmc)
mmc->ocr = cmd.response[0];
+ if (!(mmc_host_is_spi(mmc)) && (cmd.response[0] & 0x41000000)
+ == 0x41000000) {
+ err = mmc_switch_voltage(mmc, MMC_SIGNAL_VOLTAGE_180);
+ if (err)
+ return err;
+ }
+
mmc->high_capacity = ((mmc->ocr & OCR_HCS) == OCR_HCS);
mmc->rca = 0;
@@ -977,6 +1049,7 @@ static int sd_get_capabilities(struct mmc *mmc)
ALLOC_CACHE_ALIGN_BUFFER(uint, switch_status, 16);
struct mmc_data data;
int timeout;
+ u32 sd3_bus_mode;
mmc->card_caps = MMC_MODE_1BIT;
@@ -1058,6 +1131,22 @@ retry_scr:
if (__be32_to_cpu(switch_status[3]) & SD_HIGHSPEED_SUPPORTED)
mmc->card_caps |= MMC_CAP(SD_HS);
+ /* Version before 3.0 don't support UHS modes */
+ if (mmc->version < SD_VERSION_3)
+ return 0;
+
+ sd3_bus_mode = __be32_to_cpu(switch_status[3]) >> 16 & 0x1f;
+ if (sd3_bus_mode & SD_MODE_UHS_SDR104)
+ mmc->card_caps |= MMC_CAP(UHS_SDR104);
+ if (sd3_bus_mode & SD_MODE_UHS_SDR50)
+ mmc->card_caps |= MMC_CAP(UHS_SDR50);
+ if (sd3_bus_mode & SD_MODE_UHS_SDR25)
+ mmc->card_caps |= MMC_CAP(UHS_SDR25);
+ if (sd3_bus_mode & SD_MODE_UHS_SDR12)
+ mmc->card_caps |= MMC_CAP(UHS_SDR12);
+ if (sd3_bus_mode & SD_MODE_UHS_DDR50)
+ mmc->card_caps |= MMC_CAP(UHS_DDR50);
+
return 0;
}
@@ -1065,13 +1154,36 @@ static int sd_set_card_speed(struct mmc *mmc, enum bus_mode mode)
{
int err;
ALLOC_CACHE_ALIGN_BUFFER(uint, switch_status, 16);
+ int speed;
+
+ switch (mode) {
+ case SD_LEGACY:
+ case UHS_SDR12:
+ speed = UHS_SDR12_BUS_SPEED;
+ break;
+ case SD_HS:
+ case UHS_SDR25:
+ speed = UHS_SDR25_BUS_SPEED;
+ break;
+ case UHS_SDR50:
+ speed = UHS_SDR50_BUS_SPEED;
+ break;
+ case UHS_DDR50:
+ speed = UHS_DDR50_BUS_SPEED;
+ break;
+ case UHS_SDR104:
+ speed = UHS_SDR104_BUS_SPEED;
+ break;
+ default:
+ return -EINVAL;
+ }
- err = sd_switch(mmc, SD_SWITCH_SWITCH, 0, 1, (u8 *)switch_status);
+ err = sd_switch(mmc, SD_SWITCH_SWITCH, 0, speed, (u8 *)switch_status);
if (err)
return err;
- if ((__be32_to_cpu(switch_status[4]) & 0x0f000000) != 0x01000000)
+ if ((__be32_to_cpu(switch_status[4]) >> 24) != speed)
return -ENOTSUPP;
return 0;
@@ -1291,10 +1403,31 @@ static int mmc_set_signal_voltage(struct mmc *mmc, uint signal_voltage)
static const struct mode_width_tuning sd_modes_by_pref[] = {
{
+ .mode = UHS_SDR104,
+ .widths = MMC_MODE_4BIT | MMC_MODE_1BIT,
+ .tuning = MMC_SEND_TUNING_BLOCK
+ },
+ {
+ .mode = UHS_SDR50,
+ .widths = MMC_MODE_4BIT | MMC_MODE_1BIT,
+ },
+ {
+ .mode = UHS_DDR50,
+ .widths = MMC_MODE_4BIT | MMC_MODE_1BIT,
+ },
+ {
+ .mode = UHS_SDR25,
+ .widths = MMC_MODE_4BIT | MMC_MODE_1BIT,
+ },
+ {
.mode = SD_HS,
.widths = MMC_MODE_4BIT | MMC_MODE_1BIT,
},
{
+ .mode = UHS_SDR12,
+ .widths = MMC_MODE_4BIT | MMC_MODE_1BIT,
+ },
+ {
.mode = SD_LEGACY,
.widths = MMC_MODE_4BIT | MMC_MODE_1BIT,
}
@@ -1310,18 +1443,24 @@ static int sd_select_mode_and_width(struct mmc *mmc)
int err;
uint widths[] = {MMC_MODE_4BIT, MMC_MODE_1BIT};
const struct mode_width_tuning *mwt;
+ bool uhs_en = (mmc->ocr & OCR_S18R) ? true : false;
+ uint caps;
+
err = sd_get_capabilities(mmc);
if (err)
return err;
/* Restrict card's capabilities by what the host can do */
- mmc->card_caps &= (mmc->cfg->host_caps | MMC_MODE_1BIT);
+ caps = mmc->card_caps & (mmc->cfg->host_caps | MMC_MODE_1BIT);
- for_each_sd_mode_by_pref(mmc->card_caps, mwt) {
+ if (!uhs_en)
+ caps &= ~UHS_CAPS;
+
+ for_each_sd_mode_by_pref(caps, mwt) {
uint *w;
for (w = widths; w < widths + ARRAY_SIZE(widths); w++) {
- if (*w & mmc->card_caps & mwt->widths) {
+ if (*w & caps & mwt->widths) {
debug("trying mode %s width %d (at %d MHz)\n",
mmc_mode_name(mwt->mode),
bus_width(*w),
@@ -1342,6 +1481,16 @@ static int sd_select_mode_and_width(struct mmc *mmc)
mmc_select_mode(mmc, mwt->mode);
mmc_set_clock(mmc, mmc->tran_speed, false);
+ /* execute tuning if needed */
+ if (mwt->tuning && !mmc_host_is_spi(mmc)) {
+ err = mmc_execute_tuning(mmc,
+ mwt->tuning);
+ if (err) {
+ debug("tuning failed\n");
+ goto error;
+ }
+ }
+
err = sd_read_ssr(mmc);
if (!err)
return 0;
@@ -1993,6 +2142,7 @@ static void mmc_power_cycle(struct mmc *mmc)
int mmc_start_init(struct mmc *mmc)
{
bool no_card;
+ bool uhs_en = supports_uhs(mmc->cfg->host_caps);
int err;
/* we pretend there's no card when init is NULL */
@@ -2028,6 +2178,7 @@ int mmc_start_init(struct mmc *mmc)
#endif
mmc->ddr_mode = 0;
+retry:
mmc_power_cycle(mmc);
/* Reset the Card */
@@ -2043,7 +2194,11 @@ int mmc_start_init(struct mmc *mmc)
err = mmc_send_if_cond(mmc);
/* Now try to get the SD card's operating condition */
- err = sd_send_op_cond(mmc);
+ err = sd_send_op_cond(mmc, uhs_en);
+ if (err && uhs_en) {
+ uhs_en = false;
+ goto retry;
+ }
/* If the command timed out, we check for an MMC card */
if (err == -ETIMEDOUT) {
diff --git a/include/mmc.h b/include/mmc.h
index b42f686..775c47e 100644
--- a/include/mmc.h
+++ b/include/mmc.h
@@ -87,6 +87,7 @@
#define MMC_CMD_SET_BLOCKLEN 16
#define MMC_CMD_READ_SINGLE_BLOCK 17
#define MMC_CMD_READ_MULTIPLE_BLOCK 18
+#define MMC_SEND_TUNING_BLOCK 19
#define MMC_SEND_TUNING_BLOCK_HS200 21
#define MMC_CMD_SET_BLOCK_COUNT 23
#define MMC_CMD_WRITE_SINGLE_BLOCK 24
@@ -117,7 +118,8 @@
static inline bool mmc_is_tuning_cmd(uint cmdidx)
{
- if (cmdidx == MMC_SEND_TUNING_BLOCK_HS200)
+ if ((cmdidx == MMC_SEND_TUNING_BLOCK_HS200) ||
+ (cmdidx == MMC_SEND_TUNING_BLOCK))
return true;
return false;
}
@@ -126,8 +128,22 @@ static inline bool mmc_is_tuning_cmd(uint cmdidx)
#define SD_HIGHSPEED_BUSY 0x00020000
#define SD_HIGHSPEED_SUPPORTED 0x00020000
+#define UHS_SDR12_BUS_SPEED 0
+#define HIGH_SPEED_BUS_SPEED 1
+#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)
+
#define OCR_BUSY 0x80000000
#define OCR_HCS 0x40000000
+#define OCR_S18R 0x1000000
#define OCR_VOLTAGE_MASK 0x007FFF80
#define OCR_ACCESS_MODE 0x60000000
@@ -490,6 +506,15 @@ static inline bool mmc_is_mode_ddr(enum bus_mode mode)
return false;
}
+#define UHS_CAPS (MMC_CAP(UHS_SDR12) | MMC_CAP(UHS_SDR25) | \
+ MMC_CAP(UHS_SDR50) | MMC_CAP(UHS_SDR104) | \
+ MMC_CAP(UHS_DDR50))
+
+static inline bool supports_uhs(uint caps)
+{
+ return (caps & UHS_CAPS) ? true : false;
+}
+
/*
* With CONFIG_DM_MMC enabled, struct mmc can be accessed from the MMC device
--
1.9.1
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