HS400 re-tuning must be done in HS200 mode. Add the ability to switch from HS400 mode to HS200 mode before re-tuning and switch back to HS400 after re-tuning. Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx> --- drivers/mmc/core/core.h | 2 ++ drivers/mmc/core/host.c | 17 ++++++++++ drivers/mmc/core/mmc.c | 88 +++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 107 insertions(+) diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h index cfba3c0..e6f2de7 100644 --- a/drivers/mmc/core/core.h +++ b/drivers/mmc/core/core.h @@ -88,6 +88,8 @@ void mmc_remove_card_debugfs(struct mmc_card *card); void mmc_init_context_info(struct mmc_host *host); int mmc_execute_tuning(struct mmc_card *card); +int mmc_hs200_to_hs400(struct mmc_card *card); +int mmc_hs400_to_hs200(struct mmc_card *card); #endif diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index 271986c..f480cb7 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -342,6 +342,7 @@ EXPORT_SYMBOL(mmc_retune_release); int mmc_retune(struct mmc_host *host) { + bool return_to_hs400 = false; int err; if (host->retune_now) @@ -356,8 +357,24 @@ int mmc_retune(struct mmc_host *host) host->doing_retune = 1; + if (host->ios.timing == MMC_TIMING_MMC_HS400) { + err = mmc_hs400_to_hs200(host->card); + if (err) + goto out; + + return_to_hs400 = true; + + if (host->ops->prepare_hs400_tuning) + host->ops->prepare_hs400_tuning(host, &host->ios); + } + err = mmc_execute_tuning(host->card); + if (err) + goto out; + if (return_to_hs400) + err = mmc_hs200_to_hs400(host->card); +out: host->doing_retune = 0; return err; diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index 53a9cb3..5a52b26 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -1091,6 +1091,94 @@ static int mmc_select_hs400(struct mmc_card *card) return 0; } +int mmc_hs200_to_hs400(struct mmc_card *card) +{ + return mmc_select_hs400(card); +} + +/* Caller must hold re-tuning */ +static int mmc_switch_status(struct mmc_card *card) +{ + u32 status; + int err; + + err = mmc_send_status(card, &status); + if (err) + return err; + + return mmc_switch_status_error(card->host, status); +} + +int mmc_hs400_to_hs200(struct mmc_card *card) +{ + struct mmc_host *host = card->host; + bool send_status = true; + unsigned int max_dtr; + int err; + + if (host->caps & MMC_CAP_WAIT_WHILE_BUSY) + send_status = false; + + /* Reduce frequency to HS */ + max_dtr = card->ext_csd.hs_max_dtr; + mmc_set_clock(host, max_dtr); + + /* Switch HS400 to HS DDR */ + err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_HS_TIMING, + EXT_CSD_TIMING_HS, card->ext_csd.generic_cmd6_time, + true, send_status, true); + if (err) + goto out_err; + + mmc_set_timing(host, MMC_TIMING_MMC_DDR52); + + if (!send_status) { + err = mmc_switch_status(card); + if (err) + goto out_err; + } + + /* Switch HS DDR to HS */ + err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_BUS_WIDTH, + EXT_CSD_BUS_WIDTH_8, card->ext_csd.generic_cmd6_time, + true, send_status, true); + if (err) + goto out_err; + + mmc_set_timing(host, MMC_TIMING_MMC_HS); + + if (!send_status) { + err = mmc_switch_status(card); + if (err) + goto out_err; + } + + /* Switch HS to HS200 */ + err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_HS_TIMING, + EXT_CSD_TIMING_HS200, + card->ext_csd.generic_cmd6_time, true, send_status, + true); + if (err) + goto out_err; + + mmc_set_timing(host, MMC_TIMING_MMC_HS200); + + if (!send_status) { + err = mmc_switch_status(card); + if (err) + goto out_err; + } + + mmc_set_bus_speed(card); + + return 0; + +out_err: + pr_err("%s: %s failed, error %d\n", mmc_hostname(card->host), + __func__, err); + return err; +} + /* * For device supporting HS200 mode, the following sequence * should be done before executing the tuning process. -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html