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Commit 0a5b6438 authored by Seungwon Jeon's avatar Seungwon Jeon Committed by Chris Ball
Browse files

mmc: add support for HS400 mode of eMMC5.0 



This patch adds HS400 mode support for eMMC5.0 device.  HS400 mode is high
speed DDR interface timing from HS200.  Clock frequency is up to 200MHz
and only 8-bit bus width is supported. In addition, tuning process of
HS200 is required to synchronize the command response on the CMD line
because CMD input timing for HS400 mode is the same as HS200 mode.

Signed-off-by: default avatarSeungwon Jeon <tgih.jun@samsung.com>
Reviewed-by: default avatarJackey Shen <jackey.shen@amd.com>
Tested-by: default avatarJaehoon Chung <jh80.chung@samsung.com>
Acked-by: default avatarJaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: default avatarChris Ball <chris@printf.net>
parent 577fb131

drivers/mmc/core/bus.c

+1 −0
Original line number Diff line number Diff line
@@ -349,6 +349,7 @@ int mmc_add_card(struct mmc_card *card) 
			mmc_hostname(card->host),

			mmc_card_uhs(card) ? "ultra high speed " :

			(mmc_card_hs(card) ? "high speed " : ""),

			mmc_card_hs400(card) ? "HS400 " :

			(mmc_card_hs200(card) ? "HS200 " : ""),

			mmc_card_ddr52(card) ? "DDR " : "",

			uhs_bus_speed_mode, type, card->rca);

drivers/mmc/core/debugfs.c

+3 −0
Original line number Diff line number Diff line
@@ -141,6 +141,9 @@ static int mmc_ios_show(struct seq_file *s, void *data) 
	case MMC_TIMING_MMC_HS200:

		str = "mmc HS200";

		break;

	case MMC_TIMING_MMC_HS400:

		str = "mmc HS400";

		break;

	default:

		str = "invalid";

		break;

drivers/mmc/core/mmc.c

+93 −5
Original line number Diff line number Diff line
@@ -240,7 +240,7 @@ static int mmc_get_ext_csd(struct mmc_card *card, u8 **new_ext_csd) 
static void mmc_select_card_type(struct mmc_card *card)

{

	struct mmc_host *host = card->host;

	u8 card_type = card->ext_csd.raw_card_type & EXT_CSD_CARD_TYPE_MASK;

	u8 card_type = card->ext_csd.raw_card_type;

	u32 caps = host->caps, caps2 = host->caps2;

	unsigned int hs_max_dtr = 0, hs200_max_dtr = 0;

	unsigned int avail_type = 0;
@@ -281,6 +281,18 @@ static void mmc_select_card_type(struct mmc_card *card) 
		avail_type |= EXT_CSD_CARD_TYPE_HS200_1_2V;

	}



	if (caps2 & MMC_CAP2_HS400_1_8V &&

	    card_type & EXT_CSD_CARD_TYPE_HS400_1_8V) {

		hs200_max_dtr = MMC_HS200_MAX_DTR;

		avail_type |= EXT_CSD_CARD_TYPE_HS400_1_8V;

	}



	if (caps2 & MMC_CAP2_HS400_1_2V &&

	    card_type & EXT_CSD_CARD_TYPE_HS400_1_2V) {

		hs200_max_dtr = MMC_HS200_MAX_DTR;

		avail_type |= EXT_CSD_CARD_TYPE_HS400_1_2V;

	}



	card->ext_csd.hs_max_dtr = hs_max_dtr;

	card->ext_csd.hs200_max_dtr = hs200_max_dtr;

	card->mmc_avail_type = avail_type;
@@ -499,6 +511,8 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd) 
			ext_csd[EXT_CSD_PWR_CL_DDR_52_195];

		card->ext_csd.raw_pwr_cl_ddr_52_360 =

			ext_csd[EXT_CSD_PWR_CL_DDR_52_360];

		card->ext_csd.raw_pwr_cl_ddr_200_360 =

			ext_csd[EXT_CSD_PWR_CL_DDR_200_360];

	}



	if (card->ext_csd.rev >= 5) {
@@ -665,7 +679,10 @@ static int mmc_compare_ext_csds(struct mmc_card *card, unsigned bus_width) 
		(card->ext_csd.raw_pwr_cl_ddr_52_195 ==

			bw_ext_csd[EXT_CSD_PWR_CL_DDR_52_195]) &&

		(card->ext_csd.raw_pwr_cl_ddr_52_360 ==

			bw_ext_csd[EXT_CSD_PWR_CL_DDR_52_360]));

			bw_ext_csd[EXT_CSD_PWR_CL_DDR_52_360]) &&

		(card->ext_csd.raw_pwr_cl_ddr_200_360 ==

			bw_ext_csd[EXT_CSD_PWR_CL_DDR_200_360]));



	if (err)

		err = -EINVAL;
@@ -768,7 +785,9 @@ static int __mmc_select_powerclass(struct mmc_card *card, 
				ext_csd->raw_pwr_cl_52_360 :

				ext_csd->raw_pwr_cl_ddr_52_360;

		else if (host->ios.clock <= MMC_HS200_MAX_DTR)

			pwrclass_val = ext_csd->raw_pwr_cl_200_360;

			pwrclass_val = (bus_width == EXT_CSD_DDR_BUS_WIDTH_8) ?

				ext_csd->raw_pwr_cl_ddr_200_360 :

				ext_csd->raw_pwr_cl_200_360;

		break;

	default:

		pr_warning("%s: Voltage range not supported "
@@ -832,7 +851,8 @@ static void mmc_set_bus_speed(struct mmc_card *card) 
{

	unsigned int max_dtr = (unsigned int)-1;



	if (mmc_card_hs200(card) && max_dtr > card->ext_csd.hs200_max_dtr)

	if ((mmc_card_hs200(card) || mmc_card_hs400(card)) &&

	     max_dtr > card->ext_csd.hs200_max_dtr)

		max_dtr = card->ext_csd.hs200_max_dtr;

	else if (mmc_card_hs(card) && max_dtr > card->ext_csd.hs_max_dtr)

		max_dtr = card->ext_csd.hs_max_dtr;
@@ -985,6 +1005,61 @@ static int mmc_select_hs_ddr(struct mmc_card *card) 
	return err;

}



static int mmc_select_hs400(struct mmc_card *card)

{

	struct mmc_host *host = card->host;

	int err = 0;



	/*

	 * HS400 mode requires 8-bit bus width

	 */

	if (!(card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS400 &&

	      host->ios.bus_width == MMC_BUS_WIDTH_8))

		return 0;



	/*

	 * Before switching to dual data rate operation for HS400,

	 * it is required to convert from HS200 mode to HS mode.

	 */

	mmc_set_timing(card->host, MMC_TIMING_MMC_HS);

	mmc_set_bus_speed(card);



	err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,

			   EXT_CSD_HS_TIMING, EXT_CSD_TIMING_HS,

			   card->ext_csd.generic_cmd6_time,

			   true, true, true);

	if (err) {

		pr_warn("%s: switch to high-speed from hs200 failed, err:%d\n",

			mmc_hostname(host), err);

		return err;

	}



	err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,

			 EXT_CSD_BUS_WIDTH,

			 EXT_CSD_DDR_BUS_WIDTH_8,

			 card->ext_csd.generic_cmd6_time);

	if (err) {

		pr_warn("%s: switch to bus width for hs400 failed, err:%d\n",

			mmc_hostname(host), err);

		return err;

	}



	err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,

			   EXT_CSD_HS_TIMING, EXT_CSD_TIMING_HS400,

			   card->ext_csd.generic_cmd6_time,

			   true, true, true);

	if (err) {

		pr_warn("%s: switch to hs400 failed, err:%d\n",

			 mmc_hostname(host), err);

		return err;

	}



	mmc_set_timing(host, MMC_TIMING_MMC_HS400);

	mmc_set_bus_speed(card);



	return 0;

}



/*

 * For device supporting HS200 mode, the following sequence

 * should be done before executing the tuning process.
@@ -1062,13 +1137,22 @@ static int mmc_select_timing(struct mmc_card *card) 


/*

 * Execute tuning sequence to seek the proper bus operating

 * conditions for HS200, which sends CMD21 to the device.

 * conditions for HS200 and HS400, which sends CMD21 to the device.

 */

static int mmc_hs200_tuning(struct mmc_card *card)

{

	struct mmc_host *host = card->host;

	int err = 0;



	/*

	 * Timing should be adjusted to the HS400 target

	 * operation frequency for tuning process

	 */

	if (card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS400 &&

	    host->ios.bus_width == MMC_BUS_WIDTH_8)

		if (host->ops->prepare_hs400_tuning)

			host->ops->prepare_hs400_tuning(host, &host->ios);



	if (host->ops->execute_tuning) {

		mmc_host_clk_hold(host);

		err = host->ops->execute_tuning(host,
@@ -1296,6 +1380,10 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, 
		err = mmc_hs200_tuning(card);

		if (err)

			goto err;



		err = mmc_select_hs400(card);

		if (err)

			goto err;

	} else if (mmc_card_hs(card)) {

		/* Select the desired bus width optionally */

		err = mmc_select_bus_width(card);

include/linux/mmc/card.h

+1 −0
Original line number Diff line number Diff line
@@ -110,6 +110,7 @@ struct mmc_ext_csd { 
	u8			raw_pwr_cl_200_360;	/* 237 */

	u8			raw_pwr_cl_ddr_52_195;	/* 238 */

	u8			raw_pwr_cl_ddr_52_360;	/* 239 */

	u8			raw_pwr_cl_ddr_200_360;	/* 253 */

	u8			raw_bkops_status;	/* 246 */

	u8			raw_sectors[4];		/* 212 - 4 bytes */

include/linux/mmc/host.h

+14 −0
Original line number Diff line number Diff line
@@ -61,6 +61,7 @@ struct mmc_ios { 
#define MMC_TIMING_UHS_DDR50	7

#define MMC_TIMING_MMC_DDR52	8

#define MMC_TIMING_MMC_HS200	9

#define MMC_TIMING_MMC_HS400	10



	unsigned char	signal_voltage;		/* signalling voltage (1.8V or 3.3V) */
@@ -132,6 +133,9 @@ struct mmc_host_ops { 


	/* The tuning command opcode value is different for SD and eMMC cards */

	int	(*execute_tuning)(struct mmc_host *host, u32 opcode);



	/* Prepare HS400 target operating frequency depending host driver */

	int	(*prepare_hs400_tuning)(struct mmc_host *host, struct mmc_ios *ios);

	int	(*select_drive_strength)(unsigned int max_dtr, int host_drv, int card_drv);

	void	(*hw_reset)(struct mmc_host *host);

	void	(*card_event)(struct mmc_host *host);
@@ -274,6 +278,10 @@ struct mmc_host { 
#define MMC_CAP2_PACKED_CMD	(MMC_CAP2_PACKED_RD | \

				 MMC_CAP2_PACKED_WR)

#define MMC_CAP2_NO_PRESCAN_POWERUP (1 << 14)	/* Don't power up before scan */

#define MMC_CAP2_HS400_1_8V	(1 << 15)	/* Can support HS400 1.8V */

#define MMC_CAP2_HS400_1_2V	(1 << 16)	/* Can support HS400 1.2V */

#define MMC_CAP2_HS400		(MMC_CAP2_HS400_1_8V | \

				 MMC_CAP2_HS400_1_2V)



	mmc_pm_flag_t		pm_caps;	/* supported pm features */
@@ -495,4 +503,10 @@ static inline bool mmc_card_ddr52(struct mmc_card *card) 
{

	return card->host->ios.timing == MMC_TIMING_MMC_DDR52;

}



static inline bool mmc_card_hs400(struct mmc_card *card)

{

	return card->host->ios.timing == MMC_TIMING_MMC_HS400;

}



#endif /* LINUX_MMC_HOST_H */