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sd: Enables High Speed Timing for MMC protocol

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- Enables HS Timing Mode for MMC protocol.
- Reads data about HS modes from EXT_CSD for MMC.

Signed-off-by: Declan Snyder <declan.snyder@nxp.com>
This commit is contained in:
Declan Snyder 2022-09-07 15:07:54 -05:00 • committed by Carles Cufí
commit 496ded03f1
1 changed files with 57 additions and 32 deletions
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89
subsys/sd/mmc.c
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@ -75,7 +75,7 @@ static inline int mmc_set_max_freq(struct sd_card *card, struct sd_csd *card_csd
static int mmc_set_bus_width(struct sd_card *card);
/* Sets card to the fastest timing mode (using CMD6) and SDHC to max frequency */
static int mmc_set_timing(struct sd_card *card);
static int mmc_set_timing(struct sd_card *card, struct mmc_ext_csd *card_ext_csd);
/*
* Initialize MMC card for use with subsystem
@ -170,7 +170,7 @@ int mmc_card_init(struct sd_card *card)
}
/* Set timing to fastest supported */
ret = mmc_set_timing(card);
ret = mmc_set_timing(card, &card_ext_csd);
if (ret) {
return ret;
}
@ -351,35 +351,6 @@ static inline int mmc_set_max_freq(struct sd_card *card, struct sd_csd *card_csd
return 0;
}
static int mmc_set_timing(struct sd_card *card)
{
int ret;
struct sdhc_command cmd = {0};
/* Change Card Timing Mode */
cmd.opcode = SD_SWITCH;
cmd.arg = MMC_SWITCH_HS_TIMING_ARG;
cmd.response_type = SD_RSP_TYPE_R1b;
cmd.timeout_ms = CONFIG_SD_CMD_TIMEOUT;
ret = sdhc_request(card->sdhc, &cmd, NULL);
if (ret) {
LOG_DBG("Error setting bus timing: %d", ret);
return ret;
}
sdmmc_wait_ready(card);
/* Max frequency in HS mode is 52 MHz */
card->bus_io.clock = 52000000;
card->bus_io.timing = SDHC_TIMING_HS;
/* Change SDHC bus timing */
ret = sdhc_set_io(card->sdhc, &card->bus_io);
if (ret) {
return ret;
}
return 0;
}
static int mmc_set_bus_width(struct sd_card *card)
{
int ret;
@ -392,7 +363,7 @@ static int mmc_set_bus_width(struct sd_card *card)
cmd.arg = MMC_SWITCH_4_BIT_BUS_ARG;
card->bus_io.bus_width = SDHC_BUS_WIDTH4BIT;
} else {
/* If only 1 bit bus is supoprted, nothing to be done */
/* If only 1 bit bus is supported, nothing to be done */
return 0;
}
@ -414,9 +385,54 @@ static int mmc_set_bus_width(struct sd_card *card)
return ret;
}
return ret;
}
static int mmc_set_hs_timing(struct sd_card *card)
{
int ret;
struct sdhc_command cmd = {0};
/* Change Card Timing Mode */
cmd.opcode = SD_SWITCH;
cmd.arg = MMC_SWITCH_HS_TIMING_ARG;
cmd.response_type = SD_RSP_TYPE_R1b;
cmd.timeout_ms = CONFIG_SD_CMD_TIMEOUT;
ret = sdhc_request(card->sdhc, &cmd, NULL);
if (ret) {
LOG_DBG("Error setting bus timing: %d", ret);
return ret;
}
sdmmc_wait_ready(card);
/* Max frequency in HS mode is 52 MHz */
card->bus_io.clock = MMC_CLOCK_52MHZ;
card->bus_io.timing = SDHC_TIMING_HS;
/* Change SDHC bus timing */
ret = sdhc_set_io(card->sdhc, &card->bus_io);
if (ret) {
return ret;
}
return 0;
}
static int mmc_set_timing(struct sd_card *card, struct mmc_ext_csd *ext)
{
int ret;
if (ext->device_type.MMC_HS_52_DV) {
return mmc_set_HS_timing(card);
} else if (ext->device_type.MMC_HS_26_DV) {
/* Nothing to do, card is already configured for this */
return 0;
} else {
return -ENOTSUP;
}
return ret;
}
static int mmc_read_ext_csd(struct sd_card *card, struct mmc_ext_csd *card_ext_csd)
{
int ret;
@ -454,6 +470,15 @@ static inline void mmc_decode_ext_csd(struct mmc_ext_csd *ext, uint8_t *raw)
(raw[215U] << 24U) + (raw[214U] << 16U) + (raw[213U] << 8U) + (raw[212U] << 0U);
ext->bus_width = raw[183U];
ext->hs_timing = raw[185U];
ext->device_type.MMC_HS400_DDR_1200MV = ((1 << 7U) & raw[196U]);
ext->device_type.MMC_HS400_DDR_1800MV = ((1 << 6U) & raw[196U]);
ext->device_type.MMC_HS200_SDR_1200MV = ((1 << 5U) & raw[196U]);
ext->device_type.MMC_HS200_SDR_1800MV = ((1 << 4U) & raw[196U]);
ext->device_type.MMC_HS_DDR_1200MV = ((1 << 3U) & raw[196U]);
ext->device_type.MMC_HS_DDR_1800MV = ((1 << 2U) & raw[196U]);
ext->device_type.MMC_HS_52_DV = ((1 << 1U) & raw[196U]);
ext->device_type.MMC_HS_26_DV = ((1 << 0U) & raw[196U]);
ext->rev = raw[192U];
ext->power_class = (raw[187] & 0x0F);
ext->mmc_driver_strengths = raw[197U];
}