mmc: refactor SD startup to make it easier to support new modes

The SDcard startup process currently handles only 2 modes. To make it
easier to add support for more modes, let's make the process more generic
and use a list of the modes to try.
The major functional change is that when a mode fails we try the next one.
Not all modes are tried, only those supported by the card and the host.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Jean-Jacques Hiblot 2017-09-21 16:29:57 +02:00 committed by Jaehoon Chung
parent 7a96ec7459
commit d0c221fe73
2 changed files with 127 additions and 51 deletions

View File

@ -237,7 +237,8 @@ int mmc_send_status(struct mmc *mmc, int timeout)
(cmd.response[0] & MMC_STATUS_CURR_STATE) !=
MMC_STATE_PRG)
break;
else if (cmd.response[0] & MMC_STATUS_MASK) {
if (cmd.response[0] & MMC_STATUS_MASK) {
#if !defined(CONFIG_SPL_BUILD) || defined(CONFIG_SPL_LIBCOMMON_SUPPORT)
printf("Status Error: 0x%08X\n",
cmd.response[0]);
@ -610,7 +611,7 @@ static int mmc_change_freq(struct mmc *mmc)
char cardtype;
int err;
mmc->card_caps = 0;
mmc->card_caps = MMC_MODE_1BIT;
if (mmc_host_is_spi(mmc))
return 0;
@ -936,7 +937,7 @@ static int sd_switch(struct mmc *mmc, int mode, int group, u8 value, u8 *resp)
}
static int sd_change_freq(struct mmc *mmc)
static int sd_get_capabilities(struct mmc *mmc)
{
int err;
struct mmc_cmd cmd;
@ -945,7 +946,7 @@ static int sd_change_freq(struct mmc *mmc)
struct mmc_data data;
int timeout;
mmc->card_caps = 0;
mmc->card_caps = MMC_MODE_1BIT;
if (mmc_host_is_spi(mmc))
return 0;
@ -1022,26 +1023,53 @@ retry_scr:
}
/* If high-speed isn't supported, we return */
if (!(__be32_to_cpu(switch_status[3]) & SD_HIGHSPEED_SUPPORTED))
return 0;
if (__be32_to_cpu(switch_status[3]) & SD_HIGHSPEED_SUPPORTED)
mmc->card_caps |= MMC_CAP(SD_HS);
/*
* If the host doesn't support SD_HIGHSPEED, do not switch card to
* HIGHSPEED mode even if the card support SD_HIGHSPPED.
* This can avoid furthur problem when the card runs in different
* mode between the host.
*/
if (!((mmc->cfg->host_caps & MMC_MODE_HS_52MHz) &&
(mmc->cfg->host_caps & MMC_MODE_HS)))
return 0;
return 0;
}
static int sd_set_card_speed(struct mmc *mmc, enum bus_mode mode)
{
int err;
ALLOC_CACHE_ALIGN_BUFFER(uint, switch_status, 16);
err = sd_switch(mmc, SD_SWITCH_SWITCH, 0, 1, (u8 *)switch_status);
if (err)
return err;
if ((__be32_to_cpu(switch_status[4]) & 0x0f000000) == 0x01000000)
mmc->card_caps |= MMC_MODE_HS;
if ((__be32_to_cpu(switch_status[4]) & 0x0f000000) != 0x01000000)
return -ENOTSUPP;
return 0;
}
int sd_select_bus_width(struct mmc *mmc, int w)
{
int err;
struct mmc_cmd cmd;
if ((w != 4) && (w != 1))
return -EINVAL;
cmd.cmdidx = MMC_CMD_APP_CMD;
cmd.resp_type = MMC_RSP_R1;
cmd.cmdarg = mmc->rca << 16;
err = mmc_send_cmd(mmc, &cmd, NULL);
if (err)
return err;
cmd.cmdidx = SD_CMD_APP_SET_BUS_WIDTH;
cmd.resp_type = MMC_RSP_R1;
if (w == 4)
cmd.cmdarg = 2;
else if (w == 1)
cmd.cmdarg = 0;
err = mmc_send_cmd(mmc, &cmd, NULL);
if (err)
return err;
return 0;
}
@ -1133,6 +1161,18 @@ static const u8 multipliers[] = {
80,
};
static inline int bus_width(uint cap)
{
if (cap == MMC_MODE_8BIT)
return 8;
if (cap == MMC_MODE_4BIT)
return 4;
if (cap == MMC_MODE_1BIT)
return 1;
printf("invalid bus witdh capability 0x%x\n", cap);
return 0;
}
#if !CONFIG_IS_ENABLED(DM_MMC)
static void mmc_set_ios(struct mmc *mmc)
{
@ -1176,8 +1216,9 @@ void mmc_dump_capabilities(const char *text, uint caps)
printf("8, ");
if (caps & MMC_MODE_4BIT)
printf("4, ");
printf("1] modes [");
if (caps & MMC_MODE_1BIT)
printf("1, ");
printf("\b\b] modes [");
for (mode = MMC_LEGACY; mode < MMC_MODES_END; mode++)
if (MMC_CAP(mode) & caps)
printf("%s, ", mmc_mode_name(mode));
@ -1185,47 +1226,81 @@ void mmc_dump_capabilities(const char *text, uint caps)
}
#endif
static int sd_select_bus_freq_width(struct mmc *mmc)
struct mode_width_tuning {
enum bus_mode mode;
uint widths;
};
static const struct mode_width_tuning sd_modes_by_pref[] = {
{
.mode = SD_HS,
.widths = MMC_MODE_4BIT | MMC_MODE_1BIT,
},
{
.mode = SD_LEGACY,
.widths = MMC_MODE_4BIT | MMC_MODE_1BIT,
}
};
#define for_each_sd_mode_by_pref(caps, mwt) \
for (mwt = sd_modes_by_pref;\
mwt < sd_modes_by_pref + ARRAY_SIZE(sd_modes_by_pref);\
mwt++) \
if (caps & MMC_CAP(mwt->mode))
static int sd_select_mode_and_width(struct mmc *mmc)
{
int err;
struct mmc_cmd cmd;
uint widths[] = {MMC_MODE_4BIT, MMC_MODE_1BIT};
const struct mode_width_tuning *mwt;
err = sd_change_freq(mmc);
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->card_caps &= (mmc->cfg->host_caps | MMC_MODE_1BIT);
if (mmc->card_caps & MMC_MODE_4BIT) {
cmd.cmdidx = MMC_CMD_APP_CMD;
cmd.resp_type = MMC_RSP_R1;
cmd.cmdarg = mmc->rca << 16;
for_each_sd_mode_by_pref(mmc->card_caps, mwt) {
uint *w;
err = mmc_send_cmd(mmc, &cmd, NULL);
if (err)
return err;
for (w = widths; w < widths + ARRAY_SIZE(widths); w++) {
if (*w & mmc->card_caps & mwt->widths) {
debug("trying mode %s width %d (at %d MHz)\n",
mmc_mode_name(mwt->mode),
bus_width(*w),
mmc_mode2freq(mmc, mwt->mode) / 1000000);
cmd.cmdidx = SD_CMD_APP_SET_BUS_WIDTH;
cmd.resp_type = MMC_RSP_R1;
cmd.cmdarg = 2;
err = mmc_send_cmd(mmc, &cmd, NULL);
if (err)
return err;
/* configure the bus width (card + host) */
err = sd_select_bus_width(mmc, bus_width(*w));
if (err)
goto error;
mmc_set_bus_width(mmc, bus_width(*w));
mmc_set_bus_width(mmc, 4);
/* configure the bus mode (card) */
err = sd_set_card_speed(mmc, mwt->mode);
if (err)
goto error;
/* configure the bus mode (host) */
mmc_select_mode(mmc, mwt->mode);
mmc_set_clock(mmc, mmc->tran_speed);
err = sd_read_ssr(mmc);
if (!err)
return 0;
printf("bad ssr\n");
error:
/* revert to a safer bus speed */
mmc_select_mode(mmc, SD_LEGACY);
mmc_set_clock(mmc, mmc->tran_speed);
}
}
}
err = sd_read_ssr(mmc);
if (err)
return err;
if (mmc->card_caps & MMC_MODE_HS)
mmc_select_mode(mmc, SD_HS);
else
mmc_select_mode(mmc, SD_LEGACY);
return 0;
printf("unable to select a mode\n");
return -ENOTSUPP;
}
/*
@ -1290,7 +1365,7 @@ static int mmc_select_bus_freq_width(struct mmc *mmc)
return err;
/* Restrict card's capabilities by what the host can do */
mmc->card_caps &= mmc->cfg->host_caps;
mmc->card_caps &= (mmc->cfg->host_caps | MMC_MODE_1BIT);
/* Only version 4 of MMC supports wider bus widths */
if (mmc->version < MMC_VERSION_4)
@ -1685,7 +1760,7 @@ static int mmc_startup(struct mmc *mmc)
return err;
if (IS_SD(mmc))
err = sd_select_bus_freq_width(mmc);
err = sd_select_mode_and_width(mmc);
else
err = mmc_select_bus_freq_width(mmc);

View File

@ -59,6 +59,7 @@
#define MMC_MODE_8BIT BIT(30)
#define MMC_MODE_4BIT BIT(29)
#define MMC_MODE_1BIT BIT(28)
#define MMC_MODE_SPI BIT(27)