From 597dd9d79cfbbb1636d00a7fd0880355d9b20c41 Mon Sep 17 00:00:00 2001 From: Sujit Reddy Thumma Date: Mon, 14 Nov 2011 13:53:29 +0530 Subject: mmc: core: Use delayed work in clock gating framework Current clock gating framework disables the MCI clock as soon as the request is completed and enables it when a request arrives. This aggressive clock gating framework, when enabled, cause following issues: When there are back-to-back requests from the Queue layer, we unnecessarily end up disabling and enabling the clocks between these requests since 8MCLK clock cycles is a very short duration compared to the time delay between back to back requests reaching the MMC layer. This overhead can effect the overall performance depending on how long the clock enable and disable calls take which is platform dependent. For example on some platforms we can have clock control not on the local processor, but on a different subsystem and the time taken to perform the clock enable/disable can add significant overhead. Also if the host controller driver decides to disable the host clock too when mmc_set_ios function is called with ios.clock=0, it adds additional delay and it is highly possible that the next request had already arrived and unnecessarily blocked in enabling the clocks. This is seen frequently when the processor is executing at high speeds and in multi-core platforms thus reduces the overall throughput compared to if clock gating is disabled. Fix this by delaying turning off the clocks by posting request on delayed workqueue. Also cancel the unscheduled pending work, if any, when there is access to card. sysfs entry is provided to tune the delay as needed, default value set to 200ms. Signed-off-by: Sujit Reddy Thumma Acked-by: Linus Walleij Signed-off-by: Chris Ball --- Documentation/mmc/mmc-dev-attrs.txt | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'Documentation') diff --git a/Documentation/mmc/mmc-dev-attrs.txt b/Documentation/mmc/mmc-dev-attrs.txt index 8898a95b41e5..b0245565875a 100644 --- a/Documentation/mmc/mmc-dev-attrs.txt +++ b/Documentation/mmc/mmc-dev-attrs.txt @@ -64,3 +64,13 @@ Note on Erase Size and Preferred Erase Size: size specified by the card. "preferred_erase_size" is in bytes. + +SD/MMC/SDIO Clock Gating Attribute +================================== + +Read and write access is provided to following attribute. +This attribute appears only if CONFIG_MMC_CLKGATE is enabled. + + clkgate_delay Tune the clock gating delay with desired value in milli seconds. + +echo > /sys/class/mmc_host/mmcX/clkgate_delay -- cgit v1.2.3 From add710eaa88606de8ba98a014d37178579e6dbaf Mon Sep 17 00:00:00 2001 From: Johan Rudholm Date: Fri, 2 Dec 2011 08:51:06 +0100 Subject: mmc: boot partition ro lock support Enable boot partitions to be read-only locked until next power on via a sysfs entry. There will be one sysfs entry for each boot partition: /sys/block/mmcblkXbootY/ro_lock_until_next_power_on Each boot partition is locked by writing 1 to its file. Signed-off-by: Johan Rudholm Signed-off-by: John Beckett Signed-off-by: Chris Ball --- Documentation/mmc/mmc-dev-parts.txt | 13 ++++ drivers/mmc/card/block.c | 121 +++++++++++++++++++++++++++++++++--- drivers/mmc/core/mmc.c | 14 ++++- include/linux/mmc/card.h | 10 ++- include/linux/mmc/mmc.h | 6 ++ 5 files changed, 153 insertions(+), 11 deletions(-) (limited to 'Documentation') diff --git a/Documentation/mmc/mmc-dev-parts.txt b/Documentation/mmc/mmc-dev-parts.txt index 2db28b8e662f..f08d078d43cf 100644 --- a/Documentation/mmc/mmc-dev-parts.txt +++ b/Documentation/mmc/mmc-dev-parts.txt @@ -25,3 +25,16 @@ echo 0 > /sys/block/mmcblkXbootY/force_ro To re-enable read-only access: echo 1 > /sys/block/mmcblkXbootY/force_ro + +The boot partitions can also be locked read only until the next power on, +with: + +echo 1 > /sys/block/mmcblkXbootY/ro_lock_until_next_power_on + +This is a feature of the card and not of the kernel. If the card does +not support boot partition locking, the file will not exist. If the +feature has been disabled on the card, the file will be read-only. + +The boot partitions can also be locked permanently, but this feature is +not accessible through sysfs in order to avoid accidental or malicious +bricking. diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c index ad0fb8d74dda..0c959c96005e 100644 --- a/drivers/mmc/card/block.c +++ b/drivers/mmc/card/block.c @@ -107,6 +107,8 @@ struct mmc_blk_data { */ unsigned int part_curr; struct device_attribute force_ro; + struct device_attribute power_ro_lock; + int area_type; }; static DEFINE_MUTEX(open_lock); @@ -165,6 +167,70 @@ static void mmc_blk_put(struct mmc_blk_data *md) mutex_unlock(&open_lock); } +static ssize_t power_ro_lock_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int ret; + struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev)); + struct mmc_card *card = md->queue.card; + int locked = 0; + + if (card->ext_csd.boot_ro_lock & EXT_CSD_BOOT_WP_B_PERM_WP_EN) + locked = 2; + else if (card->ext_csd.boot_ro_lock & EXT_CSD_BOOT_WP_B_PWR_WP_EN) + locked = 1; + + ret = snprintf(buf, PAGE_SIZE, "%d\n", locked); + + return ret; +} + +static ssize_t power_ro_lock_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + int ret; + struct mmc_blk_data *md, *part_md; + struct mmc_card *card; + unsigned long set; + + if (kstrtoul(buf, 0, &set)) + return -EINVAL; + + if (set != 1) + return count; + + md = mmc_blk_get(dev_to_disk(dev)); + card = md->queue.card; + + mmc_claim_host(card->host); + + ret = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_BOOT_WP, + card->ext_csd.boot_ro_lock | + EXT_CSD_BOOT_WP_B_PWR_WP_EN, + card->ext_csd.part_time); + if (ret) + pr_err("%s: Locking boot partition ro until next power on failed: %d\n", md->disk->disk_name, ret); + else + card->ext_csd.boot_ro_lock |= EXT_CSD_BOOT_WP_B_PWR_WP_EN; + + mmc_release_host(card->host); + + if (!ret) { + pr_info("%s: Locking boot partition ro until next power on\n", + md->disk->disk_name); + set_disk_ro(md->disk, 1); + + list_for_each_entry(part_md, &md->part, part) + if (part_md->area_type == MMC_BLK_DATA_AREA_BOOT) { + pr_info("%s: Locking boot partition ro until next power on\n", part_md->disk->disk_name); + set_disk_ro(part_md->disk, 1); + } + } + + mmc_blk_put(md); + return count; +} + static ssize_t force_ro_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -1347,7 +1413,8 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card, struct device *parent, sector_t size, bool default_ro, - const char *subname) + const char *subname, + int area_type) { struct mmc_blk_data *md; int devidx, ret; @@ -1372,11 +1439,12 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card, if (!subname) { md->name_idx = find_first_zero_bit(name_use, max_devices); __set_bit(md->name_idx, name_use); - } - else + } else md->name_idx = ((struct mmc_blk_data *) dev_to_disk(parent)->private_data)->name_idx; + md->area_type = area_type; + /* * Set the read-only status based on the supported commands * and the write protect switch. @@ -1470,7 +1538,8 @@ static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card) size = card->csd.capacity << (card->csd.read_blkbits - 9); } - md = mmc_blk_alloc_req(card, &card->dev, size, false, NULL); + md = mmc_blk_alloc_req(card, &card->dev, size, false, NULL, + MMC_BLK_DATA_AREA_MAIN); return md; } @@ -1479,13 +1548,14 @@ static int mmc_blk_alloc_part(struct mmc_card *card, unsigned int part_type, sector_t size, bool default_ro, - const char *subname) + const char *subname, + int area_type) { char cap_str[10]; struct mmc_blk_data *part_md; part_md = mmc_blk_alloc_req(card, disk_to_dev(md->disk), size, default_ro, - subname); + subname, area_type); if (IS_ERR(part_md)) return PTR_ERR(part_md); part_md->part_type = part_type; @@ -1518,7 +1588,8 @@ static int mmc_blk_alloc_parts(struct mmc_card *card, struct mmc_blk_data *md) card->part[idx].part_cfg, card->part[idx].size >> 9, card->part[idx].force_ro, - card->part[idx].name); + card->part[idx].name, + card->part[idx].area_type); if (ret) return ret; } @@ -1547,9 +1618,16 @@ mmc_blk_set_blksize(struct mmc_blk_data *md, struct mmc_card *card) static void mmc_blk_remove_req(struct mmc_blk_data *md) { + struct mmc_card *card; + if (md) { + card = md->queue.card; if (md->disk->flags & GENHD_FL_UP) { device_remove_file(disk_to_dev(md->disk), &md->force_ro); + if ((md->area_type & MMC_BLK_DATA_AREA_BOOT) && + card->ext_csd.boot_ro_lockable) + device_remove_file(disk_to_dev(md->disk), + &md->power_ro_lock); /* Stop new requests from getting into the queue */ del_gendisk(md->disk); @@ -1578,6 +1656,7 @@ static void mmc_blk_remove_parts(struct mmc_card *card, static int mmc_add_disk(struct mmc_blk_data *md) { int ret; + struct mmc_card *card = md->queue.card; add_disk(md->disk); md->force_ro.show = force_ro_show; @@ -1587,7 +1666,33 @@ static int mmc_add_disk(struct mmc_blk_data *md) md->force_ro.attr.mode = S_IRUGO | S_IWUSR; ret = device_create_file(disk_to_dev(md->disk), &md->force_ro); if (ret) - del_gendisk(md->disk); + goto force_ro_fail; + + if ((md->area_type & MMC_BLK_DATA_AREA_BOOT) && + card->ext_csd.boot_ro_lockable) { + mode_t mode; + + if (card->ext_csd.boot_ro_lock & EXT_CSD_BOOT_WP_B_PWR_WP_DIS) + mode = S_IRUGO; + else + mode = S_IRUGO | S_IWUSR; + + md->power_ro_lock.show = power_ro_lock_show; + md->power_ro_lock.store = power_ro_lock_store; + md->power_ro_lock.attr.mode = mode; + md->power_ro_lock.attr.name = + "ro_lock_until_next_power_on"; + ret = device_create_file(disk_to_dev(md->disk), + &md->power_ro_lock); + if (ret) + goto power_ro_lock_fail; + } + return ret; + +power_ro_lock_fail: + device_remove_file(disk_to_dev(md->disk), &md->force_ro); +force_ro_fail: + del_gendisk(md->disk); return ret; } diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index fc1059bb6a08..006e932a3ae3 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -348,7 +348,8 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd) part_size = ext_csd[EXT_CSD_BOOT_MULT] << 17; mmc_part_add(card, part_size, EXT_CSD_PART_CONFIG_ACC_BOOT0 + idx, - "boot%d", idx, true); + "boot%d", idx, true, + MMC_BLK_DATA_AREA_BOOT); } } } @@ -435,7 +436,8 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd) hc_wp_grp_sz); mmc_part_add(card, part_size << 19, EXT_CSD_PART_CONFIG_ACC_GP0 + idx, - "gp%d", idx, false); + "gp%d", idx, false, + MMC_BLK_DATA_AREA_GP); } } card->ext_csd.sec_trim_mult = @@ -446,6 +448,14 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd) ext_csd[EXT_CSD_SEC_FEATURE_SUPPORT]; card->ext_csd.trim_timeout = 300 * ext_csd[EXT_CSD_TRIM_MULT]; + + /* + * Note that the call to mmc_part_add above defaults to read + * only. If this default assumption is changed, the call must + * take into account the value of boot_locked below. + */ + card->ext_csd.boot_ro_lock = ext_csd[EXT_CSD_BOOT_WP]; + card->ext_csd.boot_ro_lockable = true; } if (card->ext_csd.rev >= 5) { diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h index 6402d9224d6a..9478a6bf1bb1 100644 --- a/include/linux/mmc/card.h +++ b/include/linux/mmc/card.h @@ -71,6 +71,8 @@ struct mmc_ext_csd { bool hpi_en; /* HPI enablebit */ bool hpi; /* HPI support bit */ unsigned int hpi_cmd; /* cmd used as HPI */ + unsigned int boot_ro_lock; /* ro lock support */ + bool boot_ro_lockable; u8 raw_partition_support; /* 160 */ u8 raw_erased_mem_count; /* 181 */ u8 raw_ext_csd_structure; /* 194 */ @@ -187,6 +189,10 @@ struct mmc_part { unsigned int part_cfg; /* partition type */ char name[MAX_MMC_PART_NAME_LEN]; bool force_ro; /* to make boot parts RO by default */ + unsigned int area_type; +#define MMC_BLK_DATA_AREA_MAIN (1<<0) +#define MMC_BLK_DATA_AREA_BOOT (1<<1) +#define MMC_BLK_DATA_AREA_GP (1<<2) }; /* @@ -265,12 +271,14 @@ struct mmc_card { * This function fill contents in mmc_part. */ static inline void mmc_part_add(struct mmc_card *card, unsigned int size, - unsigned int part_cfg, char *name, int idx, bool ro) + unsigned int part_cfg, char *name, int idx, bool ro, + int area_type) { card->part[card->nr_parts].size = size; card->part[card->nr_parts].part_cfg = part_cfg; sprintf(card->part[card->nr_parts].name, name, idx); card->part[card->nr_parts].force_ro = ro; + card->part[card->nr_parts].area_type = area_type; card->nr_parts++; } diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h index 0e7135697d11..665548e639e8 100644 --- a/include/linux/mmc/mmc.h +++ b/include/linux/mmc/mmc.h @@ -280,6 +280,7 @@ struct _mmc_csd { #define EXT_CSD_RST_N_FUNCTION 162 /* R/W */ #define EXT_CSD_SANITIZE_START 165 /* W */ #define EXT_CSD_WR_REL_PARAM 166 /* RO */ +#define EXT_CSD_BOOT_WP 173 /* R/W */ #define EXT_CSD_ERASE_GROUP_DEF 175 /* R/W */ #define EXT_CSD_PART_CONFIG 179 /* R/W */ #define EXT_CSD_ERASED_MEM_CONT 181 /* RO */ @@ -321,6 +322,11 @@ struct _mmc_csd { #define EXT_CSD_WR_REL_PARAM_EN (1<<2) +#define EXT_CSD_BOOT_WP_B_PWR_WP_DIS (0x40) +#define EXT_CSD_BOOT_WP_B_PERM_WP_DIS (0x10) +#define EXT_CSD_BOOT_WP_B_PERM_WP_EN (0x04) +#define EXT_CSD_BOOT_WP_B_PWR_WP_EN (0x01) + #define EXT_CSD_PART_CONFIG_ACC_MASK (0x7) #define EXT_CSD_PART_CONFIG_ACC_BOOT0 (0x1) #define EXT_CSD_PART_CONFIG_ACC_GP0 (0x4) -- cgit v1.2.3 From 4137e50494cb3496fbb6ccd27aa7b6d7c9634c1e Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Mon, 5 Dec 2011 10:28:44 -0800 Subject: mmc: core: Fixup delayed work clock gating patch c31b50e (mmc: core: Use delayed work in clock gating framework, 2011-11-14) missed a few things during review: o A useless pr_info() o milliseconds was written as two words o The sysfs file had units in its output Fix all three problems. Signed-off-by: Stephen Boyd Cc: Sujit Reddy Thumma Signed-off-by: Chris Ball --- Documentation/mmc/mmc-dev-attrs.txt | 2 +- drivers/mmc/core/host.c | 6 +----- 2 files changed, 2 insertions(+), 6 deletions(-) (limited to 'Documentation') diff --git a/Documentation/mmc/mmc-dev-attrs.txt b/Documentation/mmc/mmc-dev-attrs.txt index b0245565875a..22ae8441489f 100644 --- a/Documentation/mmc/mmc-dev-attrs.txt +++ b/Documentation/mmc/mmc-dev-attrs.txt @@ -71,6 +71,6 @@ SD/MMC/SDIO Clock Gating Attribute Read and write access is provided to following attribute. This attribute appears only if CONFIG_MMC_CLKGATE is enabled. - clkgate_delay Tune the clock gating delay with desired value in milli seconds. + clkgate_delay Tune the clock gating delay with desired value in milliseconds. echo > /sys/class/mmc_host/mmcX/clkgate_delay diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index 817a76039743..30055f2b0d44 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -58,8 +58,7 @@ static ssize_t clkgate_delay_show(struct device *dev, struct device_attribute *attr, char *buf) { struct mmc_host *host = cls_dev_to_mmc_host(dev); - return snprintf(buf, PAGE_SIZE, "%lu millisecs\n", - host->clkgate_delay); + return snprintf(buf, PAGE_SIZE, "%lu\n", host->clkgate_delay); } static ssize_t clkgate_delay_store(struct device *dev, @@ -74,9 +73,6 @@ static ssize_t clkgate_delay_store(struct device *dev, spin_lock_irqsave(&host->clk_lock, flags); host->clkgate_delay = value; spin_unlock_irqrestore(&host->clk_lock, flags); - - pr_info("%s: clock gate delay set to %lu ms\n", - mmc_hostname(host), value); return count; } -- cgit v1.2.3