Hello Jaenhoon, I have a few suggestions regarding the situation when Host starts BKOPS:
1) Host should start BKOPS (based on BKOPS_STATUS or URGENT_BKOPS event) when going to mmc_sleep, which means that the bus is in idle state (this also covers the case in mmc_queue_thread, because in this case no I/O request exists). It seems like checking the status periodically in addition to mmc_suspend is not needed. Since if the device was in idle and we performed a single BKOPS then there is no point in performing another BKOPS unless there was actually another I/O request. 2) Also this implies an answer to the question about need to interrupt BKOPS before powering off card - the answer is no. 3) Based on statistical data we have (day long test) it looks like we do not need to do any preventive BKOPS caused by BKOPS_STATUS less than critical (0x3). Thanks, Konstantin Dorfman Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jaehoon Chung Sent: Thursday, November 17, 2011 2:50 AM To: linux-mmc Cc: Chris Ball; Kyungmin Park; Hanumath Prasad; Per Forlin; Sebastian Rasmussen; Dong, Chuanxiao; [email protected] Subject: [PATCH v3] mmc: support BKOPS feature for eMMC Enable eMMC background operations (BKOPS) feature. If URGENT_BKOPS is set after a response, note that BKOPS are required. After all I/O requests are finished, run BKOPS if required. Should read/write operations be requested during BKOPS, first issue HPI to interrupt the ongoing BKOPS and then service the request. If you want to enable this feature, set MMC_CAP2_BKOPS. Future considerations * Check BKOPS_LEVEL=1 and start BKOPS in a preventive manner. * Interrupt ongoing BKOPS before powering off the card. Signed-off-by: Jaehoon Chung <[email protected]> Signed-off-by: Kyungmin Park <[email protected]> CC: Hanumath Prasad <[email protected]> --- Changelog V3: - move the bkops setting's location in mmc_blk_issue_rw_rq - modify condition checking - bkops_en is assigned ext_csd[EXT_CSD_BKOPS_EN] instead of "1" - remove the unused code - change pr_debug instead of pr_warn in mmc_send_hpi_cmd - Add the Future consideration suggested by Per Changelog V2: - Use EXCEPTION_STATUS instead of URGENT_BKOPS - Add function to check Exception_status(for eMMC4.5) - remove unnecessary code. drivers/mmc/card/block.c | 10 +++++ drivers/mmc/card/queue.c | 4 ++ drivers/mmc/core/core.c | 87 ++++++++++++++++++++++++++++++++++++++++++++ drivers/mmc/core/mmc.c | 8 ++++ drivers/mmc/core/mmc_ops.c | 6 +++- include/linux/mmc/card.h | 12 ++++++ include/linux/mmc/core.h | 3 ++ include/linux/mmc/host.h | 1 + include/linux/mmc/mmc.h | 14 +++++++ 9 files changed, 144 insertions(+), 1 deletions(-) diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c index c80bb6d..9d19ebb 100644 --- a/drivers/mmc/card/block.c +++ b/drivers/mmc/card/block.c @@ -1188,6 +1188,16 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *rqc) type = rq_data_dir(req) == READ ? MMC_BLK_READ : MMC_BLK_WRITE; mmc_queue_bounce_post(mq_rq); + /* + * Check BKOPS urgency from each R1 response + */ + if (mmc_card_mmc(card) && + (brq->cmd.resp[0] & R1_EXCEPTION_EVENT)) { + if (mmc_is_exception_event(card, + EXT_CSD_URGENT_BKOPS)) + mmc_card_set_need_bkops(card); + } + switch (status) { case MMC_BLK_SUCCESS: case MMC_BLK_PARTIAL: diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c index dcad59c..20bb4a5 100644 --- a/drivers/mmc/card/queue.c +++ b/drivers/mmc/card/queue.c @@ -61,6 +61,9 @@ static int mmc_queue_thread(void *d) spin_unlock_irq(q->queue_lock); if (req || mq->mqrq_prev->req) { + if (mmc_card_doing_bkops(mq->card)) + mmc_interrupt_bkops(mq->card); + set_current_state(TASK_RUNNING); mq->issue_fn(mq, req); } else { @@ -68,6 +71,7 @@ static int mmc_queue_thread(void *d) set_current_state(TASK_RUNNING); break; } + mmc_start_bkops(mq->card); up(&mq->thread_sem); schedule(); down(&mq->thread_sem); diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 7ee2e07..2d2f1d5 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -238,6 +238,50 @@ mmc_start_request(struct mmc_host *host, struct mmc_request *mrq) host->ops->request(host, mrq); } +/** + * mmc_start_bkops - start BKOPS for supported cards + * @card: MMC card to start BKOPS + * + * Start background operations whenever requested. + * when the urgent BKOPS bit is set in a R1 command response + * then background operations should be started immediately. +*/ +void mmc_start_bkops(struct mmc_card *card) +{ + int err; + unsigned long flags; + + BUG_ON(!card); + if ((!card->ext_csd.bkops_en) || + !(card->host->caps2 & MMC_CAP2_BKOPS)) + return; + + /* + * If card is already doing bkops or need for + * bkops flag is not set, then do nothing just + * return + */ + if (mmc_card_doing_bkops(card) + || !mmc_card_need_bkops(card)) + return; + + mmc_claim_host(card->host); + err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, + EXT_CSD_BKOPS_START, 1, 0); + if (err) { + pr_warning("error %d starting bkops\n", err); + mmc_card_clr_need_bkops(card); + goto out; + } + spin_lock_irqsave(&card->host->lock, flags); + mmc_card_clr_need_bkops(card); + mmc_card_set_doing_bkops(card); + spin_unlock_irqrestore(&card->host->lock, flags); +out: + mmc_release_host(card->host); +} +EXPORT_SYMBOL(mmc_start_bkops); + static void mmc_wait_done(struct mmc_request *mrq) { complete(&mrq->completion); @@ -466,6 +510,49 @@ int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries EXPORT_SYMBOL(mmc_wait_for_cmd); /** + * mmc_interrupt_bkops - interrupt ongoing BKOPS + * @card: MMC card to check BKOPS + * + * Send HPI command to interrupt ongoing background operations, + * to allow rapid servicing of foreground operations,e.g. read/ + * writes. Wait until the card comes out of the programming state + * to avoid errors in servicing read/write requests. + */ +int mmc_interrupt_bkops(struct mmc_card *card) +{ + int err = 0; + unsigned long flags; + + BUG_ON(!card); + + err = mmc_interrupt_hpi(card); + + spin_lock_irqsave(&card->host->lock, flags); + mmc_card_clr_doing_bkops(card); + spin_unlock_irqrestore(&card->host->lock, flags); + + return err; +} +EXPORT_SYMBOL(mmc_interrupt_bkops); + +int mmc_is_exception_event(struct mmc_card *card, unsigned int value) +{ + int err; + u8 ext_csd[512]; + + /* In eMMC 4.41, R1_EXCEPTION_EVENT is URGENT_BKOPS */ + if (card->ext_csd.rev == 5) + return 1; + + err = mmc_send_ext_csd(card, ext_csd); + if (err) + return err; + + return (ext_csd[EXT_CSD_EXCEPTION_STATUS] & value) ? 1 : 0; +} +EXPORT_SYMBOL(mmc_is_exception_event); + +/** * mmc_set_data_timeout - set the timeout for a data command * @data: data phase for command * @card: the MMC card associated with the data transfer diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index a1223bd..514ad0f 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -448,6 +448,14 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd) } if (card->ext_csd.rev >= 5) { + /* check whether the eMMC card support BKOPS */ + if (ext_csd[EXT_CSD_BKOPS_SUPPORT] & 0x1) { + card->ext_csd.bkops = 1; + card->ext_csd.bkops_en = ext_csd[EXT_CSD_BKOPS_EN]; + card->ext_csd.raw_bkops_status = + ext_csd[EXT_CSD_BKOPS_STATUS]; + } + /* check whether the eMMC card supports HPI */ if (ext_csd[EXT_CSD_HPI_FEATURES] & 0x1) { card->ext_csd.hpi = 1; diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c index 007863e..2e397d5 100644 --- a/drivers/mmc/core/mmc_ops.c +++ b/drivers/mmc/core/mmc_ops.c @@ -398,6 +398,10 @@ int mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value, if (err) return err; + /* No need to check card status in case of BKOPS switch*/ + if (index == EXT_CSD_BKOPS_START) + return 0; + /* Must check status to be sure of no errors */ do { err = mmc_send_status(card, &status); @@ -568,7 +572,7 @@ int mmc_send_hpi_cmd(struct mmc_card *card, u32 *status) err = mmc_wait_for_cmd(card->host, &cmd, 0); if (err) { - pr_warn("%s: error %d interrupting operation. " + pr_debug("%s: error %d interrupting operation. " "HPI command response %#x\n", mmc_hostname(card->host), err, cmd.resp[0]); return err; diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h index 534974c..3c983d7 100644 --- a/include/linux/mmc/card.h +++ b/include/linux/mmc/card.h @@ -70,6 +70,8 @@ struct mmc_ext_csd { unsigned int cache_size; /* Units: KB */ bool hpi_en; /* HPI enablebit */ bool hpi; /* HPI support bit */ + bool bkops; /* background support bit */ + bool bkops_en; /* background enable bit */ unsigned int hpi_cmd; /* cmd used as HPI */ u8 raw_partition_support; /* 160 */ u8 raw_erased_mem_count; /* 181 */ @@ -84,6 +86,7 @@ struct mmc_ext_csd { u8 raw_sec_erase_mult; /* 230 */ u8 raw_sec_feature_support;/* 231 */ u8 raw_trim_mult; /* 232 */ + u8 raw_bkops_status; /* 246 */ u8 raw_sectors[4]; /* 212 - 4 bytes */ unsigned int feature_support; @@ -209,6 +212,8 @@ struct mmc_card { #define MMC_STATE_HIGHSPEED_DDR (1<<4) /* card is in high speed mode */ #define MMC_STATE_ULTRAHIGHSPEED (1<<5) /* card is in ultra high speed mode */ #define MMC_CARD_SDXC (1<<6) /* card is SDXC */ +#define MMC_STATE_NEED_BKOPS (1<<7) /* card need to do BKOPS */ +#define MMC_STATE_DOING_BKOPS (1<<8) /* card is doing BKOPS */ unsigned int quirks; /* card quirks */ #define MMC_QUIRK_LENIENT_FN0 (1<<0) /* allow SDIO FN0 writes outside of the VS CCCR range */ #define MMC_QUIRK_BLKSZ_FOR_BYTE_MODE (1<<1) /* use func->cur_blksize */ @@ -370,6 +375,8 @@ static inline void __maybe_unused remove_quirk(struct mmc_card *card, int data) #define mmc_card_uhs(c) ((c)->state & MMC_STATE_ULTRAHIGHSPEED) #define mmc_sd_card_uhs(c) ((c)->state & MMC_STATE_ULTRAHIGHSPEED) #define mmc_card_ext_capacity(c) ((c)->state & MMC_CARD_SDXC) +#define mmc_card_need_bkops(c) ((c)->state & MMC_STATE_NEED_BKOPS) +#define mmc_card_doing_bkops(c) ((c)->state & MMC_STATE_DOING_BKOPS) #define mmc_card_set_present(c) ((c)->state |= MMC_STATE_PRESENT) #define mmc_card_set_readonly(c) ((c)->state |= MMC_STATE_READONLY) @@ -379,6 +386,11 @@ static inline void __maybe_unused remove_quirk(struct mmc_card *card, int data) #define mmc_card_set_uhs(c) ((c)->state |= MMC_STATE_ULTRAHIGHSPEED) #define mmc_sd_card_set_uhs(c) ((c)->state |= MMC_STATE_ULTRAHIGHSPEED) #define mmc_card_set_ext_capacity(c) ((c)->state |= MMC_CARD_SDXC) +#define mmc_card_set_need_bkops(c) ((c)->state |= MMC_STATE_NEED_BKOPS) +#define mmc_card_set_doing_bkops(c) ((c)->state |= MMC_STATE_DOING_BKOPS) + +#define mmc_card_clr_need_bkops(c) ((c)->state &= ~MMC_STATE_NEED_BKOPS) +#define mmc_card_clr_doing_bkops(c) ((c)->state &= ~MMC_STATE_DOING_BKOPS) /* * Quirk add/remove for MMC products. diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h index 174a844..f6b997a 100644 --- a/include/linux/mmc/core.h +++ b/include/linux/mmc/core.h @@ -134,6 +134,8 @@ struct mmc_host; struct mmc_card; struct mmc_async_req; +extern int mmc_interrupt_bkops(struct mmc_card *); +extern int mmc_is_exception_event(struct mmc_card *, unsigned int); extern struct mmc_async_req *mmc_start_req(struct mmc_host *, struct mmc_async_req *, int *); extern int mmc_interrupt_hpi(struct mmc_card *); @@ -163,6 +165,7 @@ extern int mmc_can_sanitize(struct mmc_card *card); extern int mmc_can_secure_erase_trim(struct mmc_card *card); extern int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from, unsigned int nr); +extern void mmc_start_bkops(struct mmc_card *card); extern unsigned int mmc_calc_max_discard(struct mmc_card *card); extern int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen); diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 706f722..4629e84 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -242,6 +242,7 @@ struct mmc_host { #define MMC_CAP2_CACHE_CTRL (1 << 1) /* Allow cache control */ #define MMC_CAP2_POWEROFF_NOTIFY (1 << 2) /* Notify poweroff supported */ #define MMC_CAP2_NO_MULTI_READ (1 << 3) /* Multiblock reads don't work */ +#define MMC_CAP2_BKOPS (1 << 4) /* BKOPS supported */ mmc_pm_flag_t pm_caps; /* supported pm features */ unsigned int power_notify_type; diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h index 0e71356..20b1420 100644 --- a/include/linux/mmc/mmc.h +++ b/include/linux/mmc/mmc.h @@ -138,6 +138,7 @@ static inline bool mmc_op_multi(u32 opcode) #define R1_CURRENT_STATE(x) ((x & 0x00001E00) >> 9) /* sx, b (4 bits) */ #define R1_READY_FOR_DATA (1 << 8) /* sx, a */ #define R1_SWITCH_ERROR (1 << 7) /* sx, c */ +#define R1_EXCEPTION_EVENT (1 << 6) /* sx, a */ #define R1_APP_CMD (1 << 5) /* sr, c */ #define R1_STATE_IDLE 0 @@ -273,11 +274,14 @@ struct _mmc_csd { #define EXT_CSD_FLUSH_CACHE 32 /* W */ #define EXT_CSD_CACHE_CTRL 33 /* R/W */ #define EXT_CSD_POWER_OFF_NOTIFICATION 34 /* R/W */ +#define EXT_CSD_EXCEPTION_STATUS 54 /* RO */ #define EXT_CSD_GP_SIZE_MULT 143 /* R/W */ #define EXT_CSD_PARTITION_ATTRIBUTE 156 /* R/W */ #define EXT_CSD_PARTITION_SUPPORT 160 /* RO */ #define EXT_CSD_HPI_MGMT 161 /* R/W */ #define EXT_CSD_RST_N_FUNCTION 162 /* R/W */ +#define EXT_CSD_BKOPS_EN 163 /* R/W */ +#define EXT_CSD_BKOPS_START 164 /* W */ #define EXT_CSD_SANITIZE_START 165 /* W */ #define EXT_CSD_WR_REL_PARAM 166 /* RO */ #define EXT_CSD_ERASE_GROUP_DEF 175 /* R/W */ @@ -310,9 +314,11 @@ struct _mmc_csd { #define EXT_CSD_PWR_CL_200_360 237 /* RO */ #define EXT_CSD_PWR_CL_DDR_52_195 238 /* RO */ #define EXT_CSD_PWR_CL_DDR_52_360 239 /* RO */ +#define EXT_CSD_BKOPS_STATUS 246 /* RO */ #define EXT_CSD_POWER_OFF_LONG_TIME 247 /* RO */ #define EXT_CSD_GENERIC_CMD6_TIME 248 /* RO */ #define EXT_CSD_CACHE_SIZE 249 /* RO, 4 bytes */ +#define EXT_CSD_BKOPS_SUPPORT 502 /* RO */ #define EXT_CSD_HPI_FEATURES 503 /* RO */ /* @@ -373,4 +379,12 @@ struct _mmc_csd { #define MMC_SWITCH_MODE_CLEAR_BITS 0x02 /* Clear bits which are 1 in value */ #define MMC_SWITCH_MODE_WRITE_BYTE 0x03 /* Set target to value */ +/* + * EXCEPTION_EVENT_STATUS field (eMMC4.5) + */ +#define EXT_CSD_URGENT_BKOPS BIT(0) +#define EXT_CSD_DYNCAP_NEEDED BIT(1) +#define EXT_CSD_SYSPOOL_EXHAUSTED BIT(2) +#define EXT_CSD_PACKED_FAILURE BIT(3) + #endif /* LINUX_MMC_MMC_H */ -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
