Commit 52d0974e authored by Subhash Jadavani's avatar Subhash Jadavani Committed by Chris Ball
Browse files

mmc: core: hs200 fixes 



This patch fixes following issues when HS200 is enabled:

1. If executing_tuning() host ops is called without mmc_host_clk_hold(),
   card clocks might get turned off (if MMC_CLK_GATING is enabled)
   while execute_tuning() is in progress. So this patch makes sure
   that execute_tuning() is called with mmc_host_clk_hold().

2. If host timing mode is set to HS200 mode, there should not be
   any communication with the card until execute_tuning() is completed.
   But there is a chance that CMD6 might be sent to enable set HPI_EN
   (of HPI_MGMT field in EXT_CSD) before execute_tuning() is called.
   So this patch moves this operation after execute_tuning() is completed.

Signed-off-by: default avatarSubhash Jadavani <subhashj@codeaurora.org>
Reviewed-by: default avatar <girish.shivananjappa@linaro.org>
Signed-off-by: default avatarChris Ball <cjb@laptop.org>
parent 37f6190d

drivers/mmc/core/mmc.c

+21 −17
Original line number Diff line number Diff line
@@ -1046,22 +1046,6 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, 
		}

	}



	/*

	 * Enable HPI feature (if supported)

	 */

	if (card->ext_csd.hpi) {

		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,

			EXT_CSD_HPI_MGMT, 1, 0);

		if (err && err != -EBADMSG)

			goto free_card;

		if (err) {

			pr_warning("%s: Enabling HPI failed\n",

				   mmc_hostname(card->host));

			err = 0;

		} else

			card->ext_csd.hpi_en = 1;

	}



	/*

	 * Compute bus speed.

	 */
@@ -1111,9 +1095,12 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, 
		 * 4. execute tuning for HS200

		 */

		if ((host->caps2 & MMC_CAP2_HS200) &&

		    card->host->ops->execute_tuning)

		    card->host->ops->execute_tuning) {

			mmc_host_clk_hold(card->host);

			err = card->host->ops->execute_tuning(card->host,

				MMC_SEND_TUNING_BLOCK_HS200);

			mmc_host_clk_release(card->host);

		}

		if (err) {

			pr_warning("%s: tuning execution failed\n",

				   mmc_hostname(card->host));
@@ -1232,6 +1219,23 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, 
		}

	}



	/*

	 * Enable HPI feature (if supported)

	 */

	if (card->ext_csd.hpi) {

		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,

				EXT_CSD_HPI_MGMT, 1,

				card->ext_csd.generic_cmd6_time);

		if (err && err != -EBADMSG)

			goto free_card;

		if (err) {

			pr_warning("%s: Enabling HPI failed\n",

				   mmc_hostname(card->host));

			err = 0;

		} else

			card->ext_csd.hpi_en = 1;

	}



	/*

	 * If cache size is higher than 0, this indicates

	 * the existence of cache and it can be turned on.

CRA Git | Maintained and supported by SUSTech CRA and CCSE