diff --git a/drivers/mmc/am654_sdhci.c b/drivers/mmc/am654_sdhci.c index e86ef1a8b21..9549420c658 100644 --- a/drivers/mmc/am654_sdhci.c +++ b/drivers/mmc/am654_sdhci.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include #include @@ -368,7 +369,48 @@ static int am654_sdhci_deferred_probe(struct sdhci_host *host) return sdhci_probe(dev); } +#ifdef MMC_SUPPORTS_TUNING +#define ITAP_MAX 32 +static int am654_sdhci_execute_tuning(struct mmc *mmc, u8 opcode) +{ + struct udevice *dev = mmc->dev; + struct am654_sdhci_plat *plat = dev_get_plat(dev); + int cur_val, prev_val = 1, fail_len = 0, pass_window = 0, pass_len; + u32 itap; + + /* Enable ITAPDLY */ + regmap_update_bits(plat->base, PHY_CTRL4, ITAPDLYENA_MASK, + 1 << ITAPDLYENA_SHIFT); + + for (itap = 0; itap < ITAP_MAX; itap++) { + am654_sdhci_write_itapdly(plat, itap); + + cur_val = !mmc_send_tuning(mmc, opcode, NULL); + if (cur_val && !prev_val) + pass_window = itap; + + if (!cur_val) + fail_len++; + + prev_val = cur_val; + } + /* + * Having determined the length of the failing window and start of + * the passing window calculate the length of the passing window and + * set the final value halfway through it considering the range as a + * circular buffer + */ + pass_len = ITAP_MAX - fail_len; + itap = (pass_window + (pass_len >> 1)) % ITAP_MAX; + am654_sdhci_write_itapdly(plat, itap); + + return 0; +} +#endif const struct sdhci_ops am654_sdhci_ops = { +#ifdef MMC_SUPPORTS_TUNING + .platform_execute_tuning = am654_sdhci_execute_tuning, +#endif .deferred_probe = am654_sdhci_deferred_probe, .set_ios_post = &am654_sdhci_set_ios_post, .set_control_reg = &am654_sdhci_set_control_reg, @@ -408,6 +450,9 @@ static int j721e_4bit_sdhci_set_ios_post(struct sdhci_host *host) } const struct sdhci_ops j721e_4bit_sdhci_ops = { +#ifdef MMC_SUPPORTS_TUNING + .platform_execute_tuning = am654_sdhci_execute_tuning, +#endif .deferred_probe = am654_sdhci_deferred_probe, .set_ios_post = &j721e_4bit_sdhci_set_ios_post, };