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* [PATCH v4 1/1]mmc: implemented eMMC4.4 enhanced area feature
@ 2011-01-21 20:09 Chuanxiao Dong
  2011-01-22  1:51 ` Chris Ball
  0 siblings, 1 reply; 3+ messages in thread
From: Chuanxiao Dong @ 2011-01-21 20:09 UTC (permalink / raw)
  To: linux-mmc, cjb; +Cc: linux-kernel, akpm

Enhanced area feature is a new feature defined in eMMC4.4 standard. This
kind of area can help to improve the performance.

MMC driver will read out the enhanced area offset and size and add them
to be device attributes. The feature enabling should be done in manufactory.
To use this feature, bit ERASE_GRP_DEF should also be set.

Documentation/ABI/testing/sysfs-devices-mmc described the two new attributes

Signed-off-by: Chuanxiao Dong <chuanxiao.dong@intel.com>
---
 Documentation/ABI/testing/sysfs-devices-mmc |   21 +++++++
 drivers/mmc/core/mmc.c                      |   80 +++++++++++++++++++++++++++
 include/linux/mmc/card.h                    |    3 +
 include/linux/mmc/mmc.h                     |    3 +
 4 files changed, 107 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/ABI/testing/sysfs-devices-mmc

diff --git a/Documentation/ABI/testing/sysfs-devices-mmc b/Documentation/ABI/testing/sysfs-devices-mmc
new file mode 100644
index 0000000..8b18326
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-devices-mmc
@@ -0,0 +1,21 @@
+What:		/sys/devices/.../mmc_host/mmcX/mmcX:XXXX/enhanced_area_offset
+Date:		January 2011
+Contact:	Chuanxiao Dong <chuanxiao.dong@intel.com>
+Description:
+		Enhanced area is a new feature defined in eMMC4.4 standard.
+		eMMC4.4 or later card can support such feature. This kind of
+		area can help to improve the card performance. If the feature is
+		enabled, this attribute will indicate the start address of
+		enhanced data area. If not, this attribute will be -EINVAL. Unit
+		Byte. Format decimal.
+
+What:		/sys/devices/.../mmc_host/mmcX/mmcX:XXXX/enhanced_area_size
+Date:		January 2011
+Contact:	Chuanxiao Dong <chuanxiao.dong@intel.com>
+Description:
+		Enhanced area is a new feature defined in eMMC4.4 standard.
+		eMMC4.4 or later card can support such feature. This kind of
+		area can help to improve the card performance. If the feature is
+		enabled, this attribute will indicate the size of enhanced data
+		area. If not, this attribute will be -EINVAL. Unit KByte. Format
+		decimal.
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 16006ef..996e95e 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -302,6 +302,48 @@ static int mmc_read_ext_csd(struct mmc_card *card)
 	}
 
 	if (card->ext_csd.rev >= 4) {
+		/*
+		 * Enhanced area feature support
+		 * check whether eMMC card has the Enhanced area enabled.
+		 * if so, export enhanced area offset and size to
+		 * user by adding sysfs interface
+		 */
+		if ((ext_csd[EXT_CSD_PARTITION_SUPPORT] & 0x2) &&
+				(ext_csd[EXT_CSD_PARTITION_ATTRIBUTE] & 0x1)) {
+			u8 hc_erase_grp_sz =
+				ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE];
+			u8 hc_wp_grp_sz =
+				ext_csd[EXT_CSD_HC_WP_GRP_SIZE];
+			/*
+			 * set a flag to identify whether the enhanced
+			 * user data is enabled
+			 */
+			card->ext_csd.enhanced_area_en = 1;
+			/*
+			 * calculate the enhanced data area offset, unit B
+			 */
+			card->ext_csd.enhanced_area_offset =
+				(ext_csd[139] << 24) + (ext_csd[138] << 16) +
+				(ext_csd[137] << 8) + ext_csd[136];
+			if (mmc_card_blockaddr(card))
+				card->ext_csd.enhanced_area_offset <<= 9;
+			/*
+			 * calculate the enhanced data area size, unit KB
+			 */
+			card->ext_csd.enhanced_area_size =
+				(ext_csd[142] << 16) + (ext_csd[141] << 8) +
+				ext_csd[140];
+			card->ext_csd.enhanced_area_size *=
+				(size_t)(hc_erase_grp_sz * hc_wp_grp_sz);
+			card->ext_csd.enhanced_area_size <<= 9;
+		} else {
+			/*
+			 * If not enabled enhanced area, disable these
+			 * device attributes
+			 */
+			card->ext_csd.enhanced_area_offset = -EINVAL;
+			card->ext_csd.enhanced_area_size = -EINVAL;
+		}
 		card->ext_csd.sec_trim_mult =
 			ext_csd[EXT_CSD_SEC_TRIM_MULT];
 		card->ext_csd.sec_erase_mult =
@@ -336,6 +378,9 @@ MMC_DEV_ATTR(manfid, "0x%06x\n", card->cid.manfid);
 MMC_DEV_ATTR(name, "%s\n", card->cid.prod_name);
 MMC_DEV_ATTR(oemid, "0x%04x\n", card->cid.oemid);
 MMC_DEV_ATTR(serial, "0x%08x\n", card->cid.serial);
+MMC_DEV_ATTR(enhanced_area_offset, "%llu\n",
+		card->ext_csd.enhanced_area_offset);
+MMC_DEV_ATTR(enhanced_area_size, "%u\n", card->ext_csd.enhanced_area_size);
 
 static struct attribute *mmc_std_attrs[] = {
 	&dev_attr_cid.attr,
@@ -349,6 +394,8 @@ static struct attribute *mmc_std_attrs[] = {
 	&dev_attr_name.attr,
 	&dev_attr_oemid.attr,
 	&dev_attr_serial.attr,
+	&dev_attr_enhanced_area_offset.attr,
+	&dev_attr_enhanced_area_size.attr,
 	NULL,
 };
 
@@ -484,6 +531,39 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
 	}
 
 	/*
+	 * If enhanced_area_en is TRUE, host need to enable
+	 * ERASE_GRP_DEF bit.
+	 * ERASE_GRP_DEF bit will be lost everytime
+	 * after a reset or power off.
+	 */
+	if (card->ext_csd.enhanced_area_en) {
+		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
+				EXT_CSD_ERASE_GROUP_DEF, 1);
+
+		if (err && err != -EBADMSG)
+			goto free_card;
+
+		if (err) {
+			err = 0;
+			/*
+			 * Just disable enhanced area off & sz
+			 * will try to enable ERASE_GROUP_DEF
+			 * during next time reinit
+			 */
+			card->ext_csd.enhanced_area_offset = -EINVAL;
+			card->ext_csd.enhanced_area_size = -EINVAL;
+		} else {
+			card->ext_csd.erase_group_def = 1;
+			/*
+			 * enable ERASE_GRP_DEF successfully.
+			 * This will affect the erase size, so
+			 * here need to reset erase size
+			 */
+			mmc_set_erase_size(card);
+		}
+	}
+
+	/*
 	 * Activate high speed (if supported)
 	 */
 	if ((card->ext_csd.hs_max_dtr != 0) &&
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index 8ce0827..4652cf9 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -54,6 +54,9 @@ struct mmc_ext_csd {
 	unsigned int		sec_trim_mult;	/* Secure trim multiplier  */
 	unsigned int		sec_erase_mult;	/* Secure erase multiplier */
 	unsigned int		trim_timeout;		/* In milliseconds */
+	bool			enhanced_area_en;	/* enable bit */
+	unsigned long long	enhanced_area_offset;	/* Units: Byte */
+	unsigned int		enhanced_area_size;	/* Units: KB */
 };
 
 struct sd_scr {
diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index 612301f..264ba54 100644
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -253,6 +253,8 @@ struct _mmc_csd {
  * EXT_CSD fields
  */
 
+#define EXT_CSD_PARTITION_ATTRIBUTE	156	/* R/W */
+#define EXT_CSD_PARTITION_SUPPORT	160	/* RO */
 #define EXT_CSD_ERASE_GROUP_DEF		175	/* R/W */
 #define EXT_CSD_ERASED_MEM_CONT		181	/* RO */
 #define EXT_CSD_BUS_WIDTH		183	/* R/W */
@@ -262,6 +264,7 @@ struct _mmc_csd {
 #define EXT_CSD_CARD_TYPE		196	/* RO */
 #define EXT_CSD_SEC_CNT			212	/* RO, 4 bytes */
 #define EXT_CSD_S_A_TIMEOUT		217	/* RO */
+#define EXT_CSD_HC_WP_GRP_SIZE		221	/* RO */
 #define EXT_CSD_ERASE_TIMEOUT_MULT	223	/* RO */
 #define EXT_CSD_HC_ERASE_GRP_SIZE	224	/* RO */
 #define EXT_CSD_SEC_TRIM_MULT		229	/* RO */
-- 
1.6.6.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread
* Re: [PATCH v4 1/1]mmc: implemented eMMC4.4 enhanced area feature
  2011-01-21 20:09 [PATCH v4 1/1]mmc: implemented eMMC4.4 enhanced area feature Chuanxiao Dong
@ 2011-01-22  1:51 ` Chris Ball
  2011-01-22  3:00   ` Dong, Chuanxiao
  0 siblings, 1 reply; 3+ messages in thread
From: Chris Ball @ 2011-01-22  1:51 UTC (permalink / raw)
  To: Chuanxiao Dong; +Cc: linux-mmc, linux-kernel, akpm

Hi Chuanxiao,

On Sat, Jan 22, 2011 at 04:09:41AM +0800, Chuanxiao Dong wrote:
> Enhanced area feature is a new feature defined in eMMC4.4 standard. This
> kind of area can help to improve the performance.
> 
> MMC driver will read out the enhanced area offset and size and add them
> to be device attributes. The feature enabling should be done in manufactory.
> To use this feature, bit ERASE_GRP_DEF should also be set.
> 
> Documentation/ABI/testing/sysfs-devices-mmc described the two new attributes
> 
> Signed-off-by: Chuanxiao Dong <chuanxiao.dong@intel.com>

Looks good, pushed to mmc-next.  Thanks for all the edits to this!

-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child

^ permalink raw reply	[flat|nested] 3+ messages in thread
* RE: [PATCH v4 1/1]mmc: implemented eMMC4.4 enhanced area feature
  2011-01-22  1:51 ` Chris Ball
@ 2011-01-22  3:00   ` Dong, Chuanxiao
  0 siblings, 0 replies; 3+ messages in thread
From: Dong, Chuanxiao @ 2011-01-22  3:00 UTC (permalink / raw)
  To: Chris Ball; +Cc: linux-mmc, linux-kernel, akpm

Hi Chris,
Thanks for letting me know this. :)

-Chuanxiao

> -----Original Message-----
> From: Chris Ball [mailto:cjb@laptop.org]
> Sent: Saturday, January 22, 2011 9:52 AM
> To: Dong, Chuanxiao
> Cc: linux-mmc@vger.kernel.org; linux-kernel@vger.kernel.org;
> akpm@linux-foundation.org
> Subject: Re: [PATCH v4 1/1]mmc: implemented eMMC4.4 enhanced area feature
> 
> Hi Chuanxiao,
> 
> On Sat, Jan 22, 2011 at 04:09:41AM +0800, Chuanxiao Dong wrote:
> > Enhanced area feature is a new feature defined in eMMC4.4 standard. This
> > kind of area can help to improve the performance.
> >
> > MMC driver will read out the enhanced area offset and size and add them
> > to be device attributes. The feature enabling should be done in manufactory.
> > To use this feature, bit ERASE_GRP_DEF should also be set.
> >
> > Documentation/ABI/testing/sysfs-devices-mmc described the two new attributes
> >
> > Signed-off-by: Chuanxiao Dong <chuanxiao.dong@intel.com>
> 
> Looks good, pushed to mmc-next.  Thanks for all the edits to this!
> 
> --
> Chris Ball   <cjb@laptop.org>   <http://printf.net/>
> One Laptop Per Child

^ permalink raw reply	[flat|nested] 3+ messages in thread
end of thread, other threads:[~2011-01-22  3:00 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2011-01-21 20:09 [PATCH v4 1/1]mmc: implemented eMMC4.4 enhanced area feature Chuanxiao Dong
2011-01-22  1:51 ` Chris Ball
2011-01-22  3:00   ` Dong, Chuanxiao

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