Re: [PATCH v9] mmc: support BKOPS feature for eMMC

[merez@codeaurora.org]

On Wed, June 13, 2012 6:53 am, S, Venkatraman wrote:
> On Fri, Jun 8, 2012 at 10:09 AM, Jaehoon Chung <jh80.chung@samsung.com>
> wrote:
>> 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 BKOPS-STATUS is upper than LEVEL2, need to check until clear
>> the BKOPS-STATUS vaule.
>>
>> If you want to enable this feature, set MMC_CAP2_BKOPS.
>> And if you want to set the BKOPS_EN bit in ext_csd register,
>> use the MMC_CAP2_INIT_BKOPS.
>>
>> Future considerations
>>  * Check BKOPS_LEVEL=1 and start BKOPS in a preventive manner.
>>  * Interrupt ongoing BKOPS before powering off the card.
>>  * How get BKOPS_STATUS value.(periodically send ext_csd command?)
>>
>> Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
>> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
>> Signed-off-by: Konstantin Dorfman <kdorfman@codeaurora.org>
>> Signed-off-by: Maya Erez <merez@codeaurora.org>
>> ---
>> Changelog V9:
>>        - Rebased on patch-v7.
>>        - Added Konstantin and Maya's patch
>>                : mmc:core: Define synchronous BKOPS timeout
>>                : mmc:core: eMMC4.5 BKOPS fixes
>>        - Removed periodic bkops
>>                : This feature will do in future work
>>        - Add __mmc_switch() for waiting_for_prod_done.
>>
> Jaehoon,
>   (I've been trying to sync up with you offline - but our timings dont
> seem to match.)
> In essence, you've fixed most of the issue, except for the need for
> periodic BKOPS. In my view, BKOPS should have little or no overhead
> during read writes. Here is the simple workflow that I think of (and
> was discussed with some experts during Linaro connect in HK)
>
> 1) Check the status of BKOPS need when the queue has been idle for,
> say, ~5 seconds
> 2) If it's >0, start BKOPS
> 3) If a request arrives during the above execution of BKOPS, issue HPI
> and continue with the request
> 4) Else let it run indefinitely
>
> There should be no need or procedure to check BKOPS during transactions.
> If this is done, in normal circumstances, the card wouldn't need to
> set URGENT_BKOPS. Even if it is set, the above sequence would handle
> it gracefully.

We have seen write latency improvement of 6ms per block with this BKOPs
patch. In all our tests, the card didn't report of a need for a BKOPs
operation, so it is not clear if periodic BKOPs will make a real
difference.
Therefore, we think that this patch can be approved as is and periodic
BKOPs can be released as a second phase.

> Apart from this, I have just one clarification required on the
> implementation.
> See below..
>
>> Changelog V8:
>>        - Remove host->lock spin lock reviewed by Adrian
>>        - Support periodic start bkops
>>        - when bkops_status is level-3, if timeout is set to 0, send hpi.
>>        - Move the start-bkops point
>> Changelog V7:
>>        - Use HPI command when issued URGENT_BKOPS
>>        - Recheck until clearing the bkops-status bit.
>> Changelog V6:
>>        - Add the flag of check-bkops-status.
>>          (For fixing async_req problem)
>>        - Add the capability for MMC_CAP2_INIT_BKOPS.
>>          (When unset the bkops_en bit in ext_csd register)
>>        - modify the wrong condition.
>> Changelog V5:
>>        - Rebase based on the latest mmc-next.
>>        - modify codes based-on Chris's comment
>> Changelog V4:
>>        - Add mmc_read_bkops_status
>>        - When URGENT_BKOPS(level2-3), didn't use HPI command.
>>        - In mmc_switch(), use R1B/R1 according to level.
>> 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)
>> ---
>>  drivers/mmc/card/queue.c   |    2 +
>>  drivers/mmc/core/core.c    |  161
>> +++++++++++++++++++++++++++++++++++++++++++-
>>  drivers/mmc/core/mmc.c     |   18 +++++
>>  drivers/mmc/core/mmc_ops.c |   27 ++++++-
>>  include/linux/mmc/card.h   |   16 +++++
>>  include/linux/mmc/core.h   |    5 ++
>>  include/linux/mmc/host.h   |    2 +
>>  include/linux/mmc/mmc.h    |   19 +++++
>>  8 files changed, 243 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c
>> index e360a97..e4a2cde 100644
>> --- a/drivers/mmc/card/queue.c
>> +++ b/drivers/mmc/card/queue.c
>> @@ -66,6 +66,8 @@ 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_stop_bkops(mq->card);
>>                        set_current_state(TASK_RUNNING);
>>                        mq->issue_fn(mq, req);
>>                } else {
>> diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
>> index 0b6141d..9adb004 100644
>> --- a/drivers/mmc/core/core.c
>> +++ b/drivers/mmc/core/core.c
>> @@ -41,6 +41,12 @@
>>  #include "sd_ops.h"
>>  #include "sdio_ops.h"
>>
>> +/*
>> + * The Background operation can take a long time, depends on the house
>> keeping
>> + * operations the card has to peform
>> + */
>> +#define MMC_BKOPS_MAX_TIMEOUT  (4 * 80 * 1000) /* max time to wait in
>> ms */
>> +
>>  static struct workqueue_struct *workqueue;
>>  static const unsigned freqs[] = { 400000, 300000, 200000, 100000 };
>>
>> @@ -175,6 +181,16 @@ void mmc_request_done(struct mmc_host *host, struct
>> mmc_request *mrq)
>>                if (mrq->done)
>>                        mrq->done(mrq);
>>
>> +               /*
>> +                * Check BKOPS urgency from each R1 response
>> +                */
>> +               if (host->card && mmc_card_mmc(host->card) &&
>> +                       ((mmc_resp_type(cmd) == MMC_RSP_R1) ||
>> +                        (mmc_resp_type(cmd) == MMC_RSP_R1B)) &&
>> +                       (cmd->resp[0] & R1_EXCEPTION_EVENT)) {
>> +                       mmc_card_set_check_bkops(host->card);
>> +               }
>> +
>>                mmc_host_clk_release(host);
>>        }
>>  }
>> @@ -245,6 +261,74 @@ 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;
>> +       int timeout;
>> +       u8 wait_for_prog_done;
>> +
>> +       BUG_ON(!card);
>> +       if (!card->ext_csd.bkops_en || !(card->host->caps2 &
>> MMC_CAP2_BKOPS))
>> +               return;
>> +
>> +       if (mmc_card_check_bkops(card)) {
>> +               mmc_card_clr_check_bkops(card);
>> +               if (mmc_is_exception_event(card, EXT_CSD_URGENT_BKOPS))
>> +                       if (card->ext_csd.raw_bkops_status)
>> +                               mmc_card_set_need_bkops(card);
>> +       }
>> +
>> +       /*
>> +        * 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);
>> +       if (card->ext_csd.raw_bkops_status >= EXT_CSD_BKOPS_LEVEL_2) {
>> +               timeout = MMC_BKOPS_MAX_TIMEOUT;
>
> I don't think the timeout should be any different for BKOPS_START.
> IIUC, the CMD to set BKOPS_START would return immediately, and BKOPS
> will continue in the background. So the time to actually do the device
> management is not applicable to the CMD execution time..
In case of urgent BKOPs the BKOPs operation is synchronous. Therefore we
need to set the timeout to a bigger value, waiting for the BKOPs operation
to complete.
>
>> +               wait_for_prog_done = 1;
>> +       } else {
>> +               timeout = 0;
>> +               wait_for_prog_done = 0;
>> +       }
>> +
>> +       err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
>> +                       EXT_CSD_BKOPS_START, 1, timeout,
>> wait_for_prog_done);
>> +       if (err) {
>> +               pr_warn("%s: error %d starting bkops\n",
>> +                          mmc_hostname(card->host), err);
>> +               mmc_card_clr_need_bkops(card);
>> +               goto out;
>> +       }
>> +
>> +       mmc_card_clr_need_bkops(card);
>> +
>> +       /*
>> +        * For urgent bkops status (LEVEL_2 and more)
>> +        * bkops executed synchronously, otherwise
>> +        * the operation is in progress
>> +        */
>> +       if (card->ext_csd.raw_bkops_status >= EXT_CSD_BKOPS_LEVEL_2)
>> +               mmc_card_set_check_bkops(card);
>> +       else
>> +               mmc_card_set_doing_bkops(card);
>> +
>> +out:
>> +       mmc_release_host(card->host);
>> +}
>> +EXPORT_SYMBOL(mmc_start_bkops);
>> +
>>  static void mmc_wait_done(struct mmc_request *mrq)
>>  {
>>        complete(&mrq->completion);
>> @@ -359,12 +443,15 @@ struct mmc_async_req *mmc_start_req(struct
>> mmc_host *host,
>>        if (!err && areq)
>>                start_err = __mmc_start_req(host, areq->mrq);
>>
>> -       if (host->areq)
>> +       if (host->areq) {
>> +               if (!areq && host->areq && mmc_card_mmc(host->card))
>> +                       mmc_start_bkops(host->card);
>>                mmc_post_req(host, host->areq->mrq, 0);
>> +       }
>>
>>         /* Cancel a prepared request if it was not started. */
>>        if ((err || start_err) && areq)
>> -                       mmc_post_req(host, areq->mrq, -EINVAL);
>> +               mmc_post_req(host, areq->mrq, -EINVAL);
>>
>>        if (err)
>>                host->areq = NULL;
>> @@ -480,6 +567,66 @@ int mmc_wait_for_cmd(struct mmc_host *host, struct
>> mmc_command *cmd, int retries
>>  EXPORT_SYMBOL(mmc_wait_for_cmd);
>>
>>  /**
>> + *     mmc_stop_bkops - stop ongoing BKOPS
>> + *     @card: MMC card to check BKOPS
>> + *
>> + *     Send HPI command to stop 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_stop_bkops(struct mmc_card *card)
>> +{
>> +       int err = 0;
>> +
>> +       BUG_ON(!card);
>> +
>> +       err = mmc_interrupt_hpi(card);
>> +
>> +       mmc_card_clr_doing_bkops(card);
>> +
>> +       return err;
>> +}
>> +EXPORT_SYMBOL(mmc_stop_bkops);
>> +
>> +int mmc_read_bkops_status(struct mmc_card *card)
>> +{
>> +       int err;
>> +       u8 ext_csd[512];
>> +
>> +       mmc_claim_host(card->host);
>> +       err = mmc_send_ext_csd(card, ext_csd);
>> +       mmc_release_host(card->host);
>> +       if (err)
>> +               return err;
>> +
>> +       card->ext_csd.raw_bkops_status = ext_csd[EXT_CSD_BKOPS_STATUS];
>> +       card->ext_csd.raw_exception_status =
>> ext_csd[EXT_CSD_EXCEPTION_STATUS];
>> +
>> +       return 0;
>> +}
>> +EXPORT_SYMBOL(mmc_read_bkops_status);
>> +
>> +int mmc_is_exception_event(struct mmc_card *card, unsigned int value)
>> +{
>> +       int err;
>> +
>> +       err = mmc_read_bkops_status(card);
>> +       if (err) {
>> +               pr_err("%s: Didn't read bkops status : %d\n",
>> +                      mmc_hostname(card->host), err);
>> +               return 0;
>> +       }
>> +
>> +       /* In eMMC 4.41, R1_EXCEPTION_EVENT is URGENT_BKOPS */
>> +       if (card->ext_csd.rev == 5)
>> +               return 1;
>> +
>> +       return (card->ext_csd.raw_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
>> @@ -2294,8 +2441,11 @@ int mmc_suspend_host(struct mmc_host *host)
>>        mmc_bus_get(host);
>>        if (host->bus_ops && !host->bus_dead) {
>>
>> -               if (host->bus_ops->suspend)
>> +               if (host->bus_ops->suspend) {
>> +                       if (mmc_card_doing_bkops(host->card))
>> +                               mmc_stop_bkops(host->card);
>>                        err = host->bus_ops->suspend(host);
>> +               }
>>
>>                if (err == -ENOSYS || !host->bus_ops->resume) {
>>                        /*
>> @@ -2382,6 +2532,11 @@ int mmc_pm_notify(struct notifier_block
>> *notify_block,
>>        switch (mode) {
>>        case PM_HIBERNATION_PREPARE:
>>        case PM_SUSPEND_PREPARE:
>> +               if (host->card && mmc_card_mmc(host->card) &&
>> +                               mmc_card_doing_bkops(host->card)) {
>> +                       mmc_interrupt_hpi(host->card);
>> +                       mmc_card_clr_doing_bkops(host->card);
>> +               }
>>
>>                spin_lock_irqsave(&host->lock, flags);
>>                host->rescan_disable = 1;
>> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
>> index 258b203..9e036e5 100644
>> --- a/drivers/mmc/core/mmc.c
>> +++ b/drivers/mmc/core/mmc.c
>> @@ -463,6 +463,24 @@ 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];
>> +                       if (!card->ext_csd.bkops_en &&
>> +                               card->host->caps2 & MMC_CAP2_INIT_BKOPS)
>> {
>> +                               err = mmc_switch(card,
>> EXT_CSD_CMD_SET_NORMAL,
>> +                                       EXT_CSD_BKOPS_EN, 1, 0);
>> +                               if (err)
>> +                                       pr_warn("%s: Enabling BKOPS
>> failed\n",
>> +                                              
>> mmc_hostname(card->host));
>> +                               else
>> +                                       card->ext_csd.bkops_en = 1;
>> +                       }
>> +               }
>> +
>>                /* 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 69370f4..f0bebd9 100644
>> --- a/drivers/mmc/core/mmc_ops.c
>> +++ b/drivers/mmc/core/mmc_ops.c
>> @@ -367,18 +367,20 @@ int mmc_spi_set_crc(struct mmc_host *host, int
>> use_crc)
>>  }
>>
>>  /**
>> - *     mmc_switch - modify EXT_CSD register
>> + *     __mmc_switch - modify EXT_CSD register
>>  *     @card: the MMC card associated with the data transfer
>>  *     @set: cmd set values
>>  *     @index: EXT_CSD register index
>>  *     @value: value to program into EXT_CSD register
>>  *     @timeout_ms: timeout (ms) for operation performed by register
>> write,
>>  *                   timeout of zero implies maximum possible timeout
>> + *      @wait_for_prod_done: is waiting for program done
>>  *
>>  *     Modifies the EXT_CSD register for selected card.
>>  */
>> -int mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
>> -              unsigned int timeout_ms)
>> +int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
>> +              unsigned int timeout_ms, u8 wait_for_prog_done)
>> +
>>  {
>>        int err;
>>        struct mmc_command cmd = {0};
>> @@ -392,13 +394,23 @@ int mmc_switch(struct mmc_card *card, u8 set, u8
>> index, u8 value,
>>                  (index << 16) |
>>                  (value << 8) |
>>                  set;
>> -       cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
>> +
>> +       cmd.flags = MMC_CMD_AC;
>> +       if (wait_for_prog_done)
>> +               cmd.flags |= MMC_RSP_SPI_R1B | MMC_RSP_R1B;
>> +       else
>> +               cmd.flags |= MMC_RSP_R1 | MMC_RSP_R1;
>> +
>>        cmd.cmd_timeout_ms = timeout_ms;
>>
>>        err = mmc_wait_for_cmd(card->host, &cmd, MMC_CMD_RETRIES);
>>        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);
>> @@ -423,6 +435,13 @@ int mmc_switch(struct mmc_card *card, u8 set, u8
>> index, u8 value,
>>
>>        return 0;
>>  }
>> +EXPORT_SYMBOL_GPL(__mmc_switch);
>> +
>> +int mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
>> +               unsigned int timeout_ms)
>> +{
>> +       return __mmc_switch(card, set, index, value, timeout_ms, 1);
>> +}
>>  EXPORT_SYMBOL_GPL(mmc_switch);
>>
>>  int mmc_send_status(struct mmc_card *card, u32 *status)
>> diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
>> index d76513b..50b3539 100644
>> --- a/include/linux/mmc/card.h
>> +++ b/include/linux/mmc/card.h
>> @@ -76,10 +76,13 @@ struct mmc_ext_csd {
>>        bool                    hpi_en;                 /* HPI enablebit
>> */
>>        bool                    hpi;                    /* HPI support
>> bit */
>>        unsigned int            hpi_cmd;                /* cmd used as
>> HPI */
>> +       bool                    bkops;          /* background support
>> bit */
>> +       bool                    bkops_en;       /* background enable bit
>> */
>>        unsigned int            data_sector_size;       /* 512 bytes or
>> 4KB */
>>        unsigned int            data_tag_unit_size;     /* DATA TAG UNIT
>> size */
>>        unsigned int            boot_ro_lock;           /* ro lock
>> support */
>>        bool                    boot_ro_lockable;
>> +       u8                      raw_exception_status;   /* 53 */
>>        u8                      raw_partition_support;  /* 160 */
>>        u8                      raw_erased_mem_count;   /* 181 */
>>        u8                      raw_ext_csd_structure;  /* 194 */
>> @@ -93,6 +96,7 @@ 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;
>> @@ -225,6 +229,9 @@ struct mmc_card {
>>  #define MMC_CARD_REMOVED       (1<<7)          /* card has been removed
>> */
>>  #define MMC_STATE_HIGHSPEED_200        (1<<8)          /* card is in
>> HS200 mode */
>>  #define MMC_STATE_SLEEP                (1<<9)          /* card is in
>> sleep state */
>> +#define MMC_STATE_NEED_BKOPS   (1<<10)         /* card need to do BKOPS
>> */
>> +#define MMC_STATE_DOING_BKOPS  (1<<11)         /* card is doing BKOPS
>> */
>> +#define MMC_STATE_CHECK_BKOPS  (1<<12)         /* card need to check
>> 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
>> */
>> @@ -391,6 +398,9 @@ static inline void __maybe_unused
>> remove_quirk(struct mmc_card *card, int data)
>>  #define mmc_card_ext_capacity(c) ((c)->state & MMC_CARD_SDXC)
>>  #define mmc_card_removed(c)    ((c) && ((c)->state & MMC_CARD_REMOVED))
>>  #define mmc_card_is_sleep(c)   ((c)->state & MMC_STATE_SLEEP)
>> +#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_check_bkops(c) ((c)->state & MMC_STATE_CHECK_BKOPS)
>>
>>  #define mmc_card_set_present(c)        ((c)->state |=
>> MMC_STATE_PRESENT)
>>  #define mmc_card_set_readonly(c) ((c)->state |= MMC_STATE_READONLY)
>> @@ -403,7 +413,13 @@ static inline void __maybe_unused
>> remove_quirk(struct mmc_card *card, int data)
>>  #define mmc_card_set_ext_capacity(c) ((c)->state |= MMC_CARD_SDXC)
>>  #define mmc_card_set_removed(c) ((c)->state |= MMC_CARD_REMOVED)
>>  #define mmc_card_set_sleep(c)  ((c)->state |= MMC_STATE_SLEEP)
>> +#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_set_check_bkops(c) ((c)->state |=
>> MMC_STATE_CHECK_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)
>> +#define mmc_card_clr_check_bkops(c) ((c)->state &=
>> ~MMC_STATE_CHECK_BKOPS)
>>  #define mmc_card_clr_sleep(c)  ((c)->state &= ~MMC_STATE_SLEEP)
>>  /*
>>  * Quirk add/remove for MMC products.
>> diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h
>> index 1b431c7..bda3d86 100644
>> --- a/include/linux/mmc/core.h
>> +++ b/include/linux/mmc/core.h
>> @@ -134,6 +134,9 @@ struct mmc_host;
>>  struct mmc_card;
>>  struct mmc_async_req;
>>
>> +extern int mmc_stop_bkops(struct mmc_card *);
>> +extern int mmc_read_bkops_status(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 *);
>> @@ -142,6 +145,8 @@ extern int mmc_wait_for_cmd(struct mmc_host *,
>> struct mmc_command *, int);
>>  extern int mmc_app_cmd(struct mmc_host *, struct mmc_card *);
>>  extern int mmc_wait_for_app_cmd(struct mmc_host *, struct mmc_card *,
>>        struct mmc_command *, int);
>> +extern void mmc_start_bkops(struct mmc_card *card);
>> +extern int __mmc_switch(struct mmc_card *, u8, u8, u8, unsigned int,
>> u8);
>>  extern int mmc_switch(struct mmc_card *, u8, u8, u8, unsigned int);
>>
>>  #define MMC_ERASE_ARG          0x00000000
>> diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
>> index 0707d22..d23caf2 100644
>> --- a/include/linux/mmc/host.h
>> +++ b/include/linux/mmc/host.h
>> @@ -238,6 +238,8 @@ struct mmc_host {
>>  #define MMC_CAP2_BROKEN_VOLTAGE        (1 << 7)        /* Use the
>> broken voltage */
>>  #define MMC_CAP2_DETECT_ON_ERR (1 << 8)        /* On I/O err check card
>> removal */
>>  #define MMC_CAP2_HC_ERASE_SZ   (1 << 9)        /* High-capacity erase
>> size */
>> +#define MMC_CAP2_INIT_BKOPS    (1 << 10)       /* To enable BKOPS */
>> +#define MMC_CAP2_BKOPS         (1 << 11)       /* 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 d425cab..80cfbf1 100644
>> --- a/include/linux/mmc/mmc.h
>> +++ b/include/linux/mmc/mmc.h
>> @@ -139,6 +139,7 @@ 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
>> @@ -274,12 +275,15 @@ 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_DATA_SECTOR_SIZE       61      /* R */
>>  #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_BOOT_WP                        173     /* R/W */
>> @@ -313,11 +317,13 @@ 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_TAG_UNIT_SIZE          498     /* RO */
>>  #define EXT_CSD_DATA_TAG_SUPPORT       499     /* RO */
>> +#define EXT_CSD_BKOPS_SUPPORT          502     /* RO */
>>  #define EXT_CSD_HPI_FEATURES           503     /* RO */
>>
>>  /*
>> @@ -386,4 +392,17 @@ 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
>> */
>>
>> +/*
>> + * BKOPS status level
>> + */
>> +#define EXT_CSD_BKOPS_LEVEL_2          0x2
>> +
>> +/*
>> + * 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 */
>> --
>> 1.7.4.1
>

Thanks,
Maya

-- 
Sent by consultant of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum