From 709de99df0ecf3102e7728fbd876a3591859f423 Mon Sep 17 00:00:00 2001 From: Chuanxiao Dong Date: Sat, 22 Jan 2011 04:09:41 +0800 Subject: mmc: export eMMC4.4 enhanced area details to sysfs Enhanced area feature is a new feature defined in eMMC4.4 standard. This user data area provides higher performance/reliability, at the expense of using twice the effective media space due to the area using SLC. The MMC driver now reads out the enhanced area offset and size and adds them to the device attributes in sysfs. Enabling the enhanced area can only be done once, and should be done in manufacturing. To use this feature, bit ERASE_GRP_DEF should also be set. Documentation/ABI/testing/sysfs-devices-mmc describes the two new attributes. Signed-off-by: Chuanxiao Dong Reviewed-by: Chris Ball Signed-off-by: Chris Ball --- drivers/mmc/core/mmc.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 74 insertions(+) (limited to 'drivers/mmc/core/mmc.c') diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index 16006ef153f..6396c5d98e8 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -302,6 +302,44 @@ static int mmc_read_ext_csd(struct mmc_card *card) } if (card->ext_csd.rev >= 4) { + /* + * Enhanced area feature support -- check whether the 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]; + + card->ext_csd.enhanced_area_en = 1; + /* + * calculate the enhanced data area offset, in bytes + */ + 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, in kilobytes + */ + 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 the enhanced area is not enabled, 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 +374,9 @@ 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 +390,8 @@ 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, }; @@ -483,6 +526,37 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, mmc_set_erase_size(card); } + /* + * If enhanced_area_en is TRUE, host needs to enable ERASE_GRP_DEF + * bit. This 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) */ -- cgit v1.2.3