On 05/13/2017 03:16 AM, Jean-Jacques Hiblot wrote:
> 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 <jjhib...@ti.com>
> ---
> drivers/mmc/mmc.c | 238
> +++++++++++++++++++++++++++++++++---------------------
> include/mmc.h | 15 +++-
> 2 files changed, 157 insertions(+), 96 deletions(-)
>
> diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
> index f42a0fe..2931871 100644
> --- a/drivers/mmc/mmc.c
> +++ b/drivers/mmc/mmc.c
> @@ -200,6 +200,7 @@ 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;
> @@ -602,11 +603,46 @@ 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;
>
> @@ -617,38 +653,23 @@ 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;
> }
> @@ -1320,33 +1341,58 @@ static int mmc_read_and_compare_ext_csd(struct mmc
> *mmc)
> }
>
>
> -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_BUS_WIDTH_8 | EXT_CSD_DDR},
> + {MMC_MODE_4BIT, true, EXT_CSD_BUS_WIDTH_4 | EXT_CSD_DDR},
> + {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 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 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 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;
>
> @@ -1357,60 +1403,64 @@ static int mmc_select_bus_freq_width(struct mmc *mmc)
> if (mmc->version < MMC_VERSION_4)
> return 0;
>
> +
> if (!mmc->ext_csd) {
> error("No ext_csd found!\n"); /* this should enver happen */
> 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];
> + 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);
>
> - /*
> - * 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);
> + /* 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);
> + 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) {
> + 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)
> @@ -1747,7 +1797,7 @@ 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 1ffa7ec..3c6971d 100644
> --- a/include/mmc.h
> +++ b/include/mmc.h
> @@ -213,9 +213,10 @@
> #define EXT_CSD_BUS_WIDTH_1 0 /* Card is in 1 bit mode */
> #define EXT_CSD_BUS_WIDTH_4 1 /* Card is in 4 bit mode */
> #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 4 /* Card is in DDR mode */
Why do you change to 4 as 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)
> @@ -424,6 +425,16 @@ 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().
>
_______________________________________________
U-Boot mailing list
U-Boot@lists.denx.de
https://lists.denx.de/listinfo/u-boot
