The MMC startup process currently handles 4 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 --- drivers/mmc/mmc.c | 241 +++++++++++++++++++++++++++++++++--------------------- include/mmc.h | 11 +++ 2 files changed, 158 insertions(+), 94 deletions(-)
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c index b8e726a..7361447 100644 --- a/drivers/mmc/mmc.c +++ b/drivers/mmc/mmc.c @@ -202,6 +202,7 @@ static int mmc_select_mode(struct mmc *mmc, enum bus_mode mode) { mmc->selected_mode = mode; mmc->tran_speed = mmc_mode2freq(mmc, mode); + mmc->ddr_mode = mmc_is_mode_ddr(mode); debug("selecting mode %s (freq : %d MHz)\n", mmc_mode_name(mode), mmc->tran_speed / 1000000); return 0; @@ -605,11 +606,47 @@ int mmc_switch(struct mmc *mmc, u8 set, u8 index, u8 value)
}
-static int mmc_change_freq(struct mmc *mmc) +static int mmc_set_card_speed(struct mmc *mmc, enum bus_mode mode) { - ALLOC_CACHE_ALIGN_BUFFER(u8, ext_csd, MMC_MAX_BLOCK_LEN); - char cardtype; int err; + int speed_bits; + + ALLOC_CACHE_ALIGN_BUFFER(u8, test_csd, MMC_MAX_BLOCK_LEN); + + switch (mode) { + case MMC_HS: + case MMC_HS_52: + case MMC_DDR_52: + speed_bits = EXT_CSD_TIMING_HS; + case MMC_LEGACY: + speed_bits = EXT_CSD_TIMING_LEGACY; + break; + default: + return -EINVAL; + } + err = mmc_switch(mmc, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_HS_TIMING, + speed_bits); + if (err) + return err; + + if ((mode == MMC_HS) || (mode == MMC_HS_52)) { + /* Now check to see that it worked */ + err = mmc_send_ext_csd(mmc, test_csd); + if (err) + return err; + + /* No high-speed support */ + if (!test_csd[EXT_CSD_HS_TIMING]) + return -ENOTSUPP; + } + + return 0; +} + +static int mmc_get_capabilities(struct mmc *mmc) +{ + u8 *ext_csd = mmc->ext_csd; + char cardtype;
mmc->card_caps = MMC_MODE_1BIT;
@@ -620,38 +657,23 @@ static int mmc_change_freq(struct mmc *mmc) if (mmc->version < MMC_VERSION_4) return 0;
- mmc->card_caps |= MMC_MODE_4BIT | MMC_MODE_8BIT; - - err = mmc_send_ext_csd(mmc, ext_csd); + if (!ext_csd) { + error("No ext_csd found!\n"); /* this should enver happen */ + return -ENOTSUPP; + }
- if (err) - return err; + mmc->card_caps |= MMC_MODE_4BIT | MMC_MODE_8BIT;
cardtype = ext_csd[EXT_CSD_CARD_TYPE] & 0xf;
- err = mmc_switch(mmc, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_HS_TIMING, 1); - - if (err) - return err; - - /* Now check to see that it worked */ - err = mmc_send_ext_csd(mmc, ext_csd); - - if (err) - return err; - - /* No high-speed support */ - if (!ext_csd[EXT_CSD_HS_TIMING]) - return 0; - /* High Speed is set, there are two types: 52MHz and 26MHz */ if (cardtype & EXT_CSD_CARD_TYPE_52) { - if (cardtype & EXT_CSD_CARD_TYPE_DDR_1_8V) + if (cardtype & EXT_CSD_CARD_TYPE_DDR_52) mmc->card_caps |= MMC_MODE_DDR_52MHz; - mmc->card_caps |= MMC_MODE_HS_52MHz | MMC_MODE_HS; - } else { - mmc->card_caps |= MMC_MODE_HS; + mmc->card_caps |= MMC_MODE_HS_52MHz; } + if (cardtype & EXT_CSD_CARD_TYPE_26) + mmc->card_caps |= MMC_MODE_HS;
return 0; } @@ -1334,33 +1356,60 @@ static int mmc_read_and_compare_ext_csd(struct mmc *mmc) return -EBADMSG; }
-static int mmc_select_bus_freq_width(struct mmc *mmc) +static const struct mode_width_tuning mmc_modes_by_pref[] = { + { + .mode = MMC_HS_200, + .widths = MMC_MODE_8BIT | MMC_MODE_4BIT, + }, + { + .mode = MMC_DDR_52, + .widths = MMC_MODE_8BIT | MMC_MODE_4BIT, + }, + { + .mode = MMC_HS_52, + .widths = MMC_MODE_8BIT | MMC_MODE_4BIT | MMC_MODE_1BIT, + }, + { + .mode = MMC_HS, + .widths = MMC_MODE_8BIT | MMC_MODE_4BIT | MMC_MODE_1BIT, + }, + { + .mode = MMC_LEGACY, + .widths = MMC_MODE_8BIT | MMC_MODE_4BIT | MMC_MODE_1BIT, + } +}; + +#define for_each_mmc_mode_by_pref(caps, mwt) \ + for (mwt = mmc_modes_by_pref;\ + mwt < mmc_modes_by_pref + ARRAY_SIZE(mmc_modes_by_pref);\ + mwt++) \ + if (caps & MMC_CAP(mwt->mode)) + +static const struct ext_csd_bus_width { + uint cap; + bool is_ddr; + uint ext_csd_bits; +} ext_csd_bus_width[] = { + {MMC_MODE_8BIT, true, EXT_CSD_DDR_BUS_WIDTH_8}, + {MMC_MODE_4BIT, true, EXT_CSD_DDR_BUS_WIDTH_4}, + {MMC_MODE_8BIT, false, EXT_CSD_BUS_WIDTH_8}, + {MMC_MODE_4BIT, false, EXT_CSD_BUS_WIDTH_4}, + {MMC_MODE_1BIT, false, EXT_CSD_BUS_WIDTH_1}, +}; + +#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);\ + ecbv++) \ + if ((ddr == ecbv->is_ddr) && (caps & ecbv->cap)) + +static int mmc_select_mode_and_width(struct mmc *mmc) { - /* An array of possible bus widths in order of preference */ - static const unsigned int ext_csd_bits[] = { - EXT_CSD_DDR_BUS_WIDTH_8, - EXT_CSD_DDR_BUS_WIDTH_4, - EXT_CSD_BUS_WIDTH_8, - EXT_CSD_BUS_WIDTH_4, - EXT_CSD_BUS_WIDTH_1, - }; - /* An array to map CSD bus widths to host cap bits */ - static const unsigned int ext_to_hostcaps[] = { - [EXT_CSD_DDR_BUS_WIDTH_4] = - MMC_MODE_DDR_52MHz | MMC_MODE_4BIT, - [EXT_CSD_DDR_BUS_WIDTH_8] = - MMC_MODE_DDR_52MHz | MMC_MODE_8BIT, - [EXT_CSD_BUS_WIDTH_4] = MMC_MODE_4BIT, - [EXT_CSD_BUS_WIDTH_8] = MMC_MODE_8BIT, - }; - /* An array to map chosen bus width to an integer */ - static const unsigned int widths[] = { - 8, 4, 8, 4, 1, - }; int err; - int idx; + const struct mode_width_tuning *mwt; + const struct ext_csd_bus_width *ecbw;
- err = mmc_change_freq(mmc); + err = mmc_get_capabilities(mmc); if (err) return err;
@@ -1376,54 +1425,58 @@ static int mmc_select_bus_freq_width(struct mmc *mmc) return -ENOTSUPP; }
- for (idx = 0; idx < ARRAY_SIZE(ext_csd_bits); idx++) { - unsigned int extw = ext_csd_bits[idx]; - unsigned int caps = ext_to_hostcaps[extw]; - /* - * If the bus width is still not changed, - * don't try to set the default again. - * Otherwise, recover from switch attempts - * by switching to 1-bit bus width. - */ - if (extw == EXT_CSD_BUS_WIDTH_1 && - mmc->bus_width == 1) { - err = 0; - break; - } - - /* - * Check to make sure the card and controller support - * these capabilities - */ - if ((mmc->card_caps & caps) != caps) - continue; - - err = mmc_switch(mmc, EXT_CSD_CMD_SET_NORMAL, - EXT_CSD_BUS_WIDTH, extw); + for_each_mmc_mode_by_pref(mmc->card_caps, mwt) { + for_each_supported_width(mmc->card_caps & mwt->widths, + mmc_is_mode_ddr(mwt->mode), ecbw) { + debug("trying mode %s width %d (at %d MHz)\n", + mmc_mode_name(mwt->mode), + bus_width(ecbw->cap), + mmc_mode2freq(mmc, mwt->mode) / 1000000); + /* configure the bus width (card + host) */ + err = mmc_switch(mmc, EXT_CSD_CMD_SET_NORMAL, + EXT_CSD_BUS_WIDTH, + ecbw->ext_csd_bits & ~EXT_CSD_DDR_FLAG); + if (err) + goto error; + mmc_set_bus_width(mmc, bus_width(ecbw->cap));
- if (err) - continue; + /* configure the bus speed (card) */ + err = mmc_set_card_speed(mmc, mwt->mode); + if (err) + goto error; + + /* + * configure the bus width AND the ddr mode (card) + * The host side will be taken care of in the next step + */ + if (ecbw->ext_csd_bits & EXT_CSD_DDR_FLAG) { + err = mmc_switch(mmc, EXT_CSD_CMD_SET_NORMAL, + EXT_CSD_BUS_WIDTH, + ecbw->ext_csd_bits); + if (err) + goto error; + }
- mmc->ddr_mode = (caps & MMC_MODE_DDR_52MHz) ? 1 : 0; - mmc_set_bus_width(mmc, widths[idx]); + /* configure the bus mode (host) */ + mmc_select_mode(mmc, mwt->mode); + mmc_set_clock(mmc, mmc->tran_speed);
- err = mmc_read_and_compare_ext_csd(mmc); - if (!err) - break; + /* do a transfer to check the configuration */ + err = mmc_read_and_compare_ext_csd(mmc); + if (!err) + return 0; +error: + /* if an error occured, revert to a safer bus mode */ + mmc_switch(mmc, EXT_CSD_CMD_SET_NORMAL, + EXT_CSD_BUS_WIDTH, EXT_CSD_BUS_WIDTH_1); + mmc_select_mode(mmc, MMC_LEGACY); + mmc_set_bus_width(mmc, 1); + } }
- if (err) - return err; - - if (mmc->card_caps & MMC_MODE_HS_52MHz) { - if (mmc->ddr_mode) - mmc_select_mode(mmc, MMC_DDR_52); - else - mmc_select_mode(mmc, MMC_HS_52); - } else if (mmc->card_caps & MMC_MODE_HS) - mmc_select_mode(mmc, MMC_HS); + error("unable to select a mode\n");
- return err; + return -ENOTSUPP; }
static int mmc_startup_v4(struct mmc *mmc) @@ -1762,7 +1815,7 @@ static int mmc_startup(struct mmc *mmc) if (IS_SD(mmc)) err = sd_select_mode_and_width(mmc); else - err = mmc_select_bus_freq_width(mmc); + err = mmc_select_mode_and_width(mmc);
if (err) return err; diff --git a/include/mmc.h b/include/mmc.h index 9fe6a87..988bf17 100644 --- a/include/mmc.h +++ b/include/mmc.h @@ -215,7 +215,10 @@ #define EXT_CSD_BUS_WIDTH_8 2 /* Card is in 8 bit mode */ #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_TIMING_LEGACY 0 /* no high speed */ +#define EXT_CSD_TIMING_HS 1 /* HS */ #define EXT_CSD_BOOT_ACK_ENABLE (1 << 6) #define EXT_CSD_BOOT_PARTITION_ENABLE (1 << 3) #define EXT_CSD_PARTITION_ACCESS_ENABLE (1 << 0) @@ -429,6 +432,14 @@ enum bus_mode { const char *mmc_mode_name(enum bus_mode mode); void mmc_dump_capabilities(const char *text, uint caps);
+static inline bool mmc_is_mode_ddr(enum bus_mode mode) +{ + if ((mode == MMC_DDR_52) || (mode == UHS_DDR50)) + return true; + else + return false; +} + /* * With CONFIG_DM_MMC enabled, struct mmc can be accessed from the MMC device * with mmc_get_mmc_dev().