On 05/11/2012 08:40 PM, S, Venkatraman wrote:
> On Thu, May 10, 2012 at 7:07 PM, Jaehoon Chung <jh80.chung@xxxxxxxxxxx> 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.
>>
>> When BKOPS_STATUS is Level-3, if we're waiting for done, it spent 60~80sec.
>> So Added timeout value. if timeout value is set to 0, send hpi command.
>>
>> Signed-off-by: Jaehoon Chung <jh80.chung@xxxxxxxxxxx>
>> Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
>> ---
>> 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 | 170 +++++++++++++++++++++++++++++++++++++++++++-
>> drivers/mmc/core/host.c | 1 +
>> drivers/mmc/core/mmc.c | 18 +++++
>> drivers/mmc/core/mmc_ops.c | 4 +
>> include/linux/mmc/card.h | 16 ++++
>> include/linux/mmc/core.h | 5 ++
>> include/linux/mmc/host.h | 4 +
>> include/linux/mmc/mmc.h | 20 +++++
>> 9 files changed, 238 insertions(+), 2 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..91a03d5 100644
>> --- a/drivers/mmc/core/core.c
>> +++ b/drivers/mmc/core/core.c
>> @@ -175,6 +175,13 @@ 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) &&
>> + (cmd->resp[0] & R1_EXCEPTION_EVENT))
>> + mmc_card_set_check_bkops(host->card);
>> +
>> mmc_host_clk_release(host);
>> }
>> }
>> @@ -245,6 +252,76 @@ mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
>> host->ops->request(host, mrq);
>> }
>>
>> +static void mmc_send_bkops_cmd(struct mmc_card *card)
>> +{
>> + int err;
>> +
>> + BUG_ON(!card);
>> +
>> + err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
>> + EXT_CSD_BKOPS_START, 1, 0);
>> + if (err) {
>> + pr_warning("%s: error %d starting bkops\n",
>> + mmc_hostname(card->host), err);
>> + mmc_card_clr_need_bkops(card);
>> + return;
>> + }
>> +
>> + mmc_card_clr_need_bkops(card);
>> + mmc_card_set_doing_bkops(card);
>> +
>> +}
>> +
>> +void mmc_start_periodic_bkops(struct work_struct *work)
>
> There's nothing periodic about this function, by looking at the contents.
> Maybe this one should be called mmc_start_bkops ..
Well...i will checked this point..i tested with eMMC4.5 card...In my case, working this function.
But in your case, didn't work nothing..i will rework to this point after debugging.
>
>> +{
>> + struct mmc_host *host = container_of(work, struct mmc_host,
>> + start_bkops.work);
>> +
>> + mmc_card_set_check_bkops(host->card);
> Why is this being set here. The condition should be in the caller context.
>
>> +
>> + mmc_claim_host(host);
>> + mmc_start_bkops(host->card);
>> + mmc_release_host(host);
>> +}
>> +EXPORT_SYMBOL(mmc_start_periodic_bkops);
>> +
>> +/**
>> + * 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)
>
> .. and this one should be called __mmc_start_bkops() ?
Sure..i will change that.
>
>> +{
>> + 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);
>
> This breaks abstraction. Why check ext_csd even after URGENT_BKOPS is set ?
You means that need not to check ext_csd?
Well I didn't think so, we need to check bkops-status register
>
>> + } else
>> + mmc_card_clr_need_bkops(card);
>> + }
>> +
>> + /*
>> + * If card_need_bkops_flag didn't set, then do nothing just
>> + * return
>> + */
>> + if (mmc_card_doing_bkops(card) || !mmc_card_need_bkops(card))
>> + goto check_bkops;
>> +
>> + mmc_send_bkops_cmd(card);
>> +
>> +check_bkops:
>> + queue_delayed_work(system_nrt_wq, &card->host->start_bkops, 5 * HZ);
>
> IIUC, queue_delayed_work->start_bkops = mmc_start_periodic_bkops ->
> mmc_start_bkops -> queue_delayed_work
> .. ad infinitum ?
Actually, i want to get review for this point..How did you think about?
>
>> +}
>> +EXPORT_SYMBOL(mmc_start_bkops);
>> +
>> static void mmc_wait_done(struct mmc_request *mrq)
>> {
>> complete(&mrq->completion);
>> @@ -348,8 +425,10 @@ struct mmc_async_req *mmc_start_req(struct mmc_host *host,
>> struct mmc_async_req *data = host->areq;
>>
>> /* Prepare a new request */
>> - if (areq)
>> + if (areq) {
>> + cancel_delayed_work_sync(&host->start_bkops);
>> mmc_pre_req(host, areq->mrq, !host->areq);
>> + }
>>
>> if (host->areq) {
>> mmc_wait_for_req_done(host, host->areq->mrq);
>> @@ -359,8 +438,11 @@ 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) {
>> mmc_post_req(host, host->areq->mrq, 0);
>> + if (!areq && host->areq && mmc_card_mmc(host->card))
>> + mmc_start_bkops(host->card);
>> + }
>>
>> /* Cancel a prepared request if it was not started. */
>> if ((err || start_err) && areq)
>> @@ -480,6 +562,84 @@ 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 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_stop_bkops(struct mmc_card *card)
>> +{
>> + int err = 0;
>> + unsigned int timeout = 0x10000;
>> + u32 status;
>> +
>> + BUG_ON(!card);
>> + cancel_delayed_work_sync(&card->host->start_bkops);
>> +
>> + if (card->ext_csd.raw_bkops_status == EXT_CSD_BKOPS_LEVEL_3) {
>> + do {
>> + if (timeout == 0)
>> + break;
>> + mmc_claim_host(card->host);
>> + mmc_send_status(card, &status);
>> + mmc_release_host(card->host);
>> +
>> + timeout--;
>> + } while (R1_CURRENT_STATE(status) == R1_STATE_PRG);
>> + if (timeout != 0)
>> + goto done;
>> + }
>
> This won't necessarily work all the time. Once BKOPS_START is issued, the card
> might finish GC and move to transfer state even before HPI can be sent.
> So just exit if the card is in transfer state already.
Right..But if didn't wait for prog-done, we can issue the HPI.
(If didn't use Busy waiting flag)
>
> In this context, kdorfman's comments on "mmc:fix HPI execution
> sequence" makes sense.
>
>> +
>> + err = mmc_interrupt_hpi(card);
>> +
>> +done:
>> + 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;
>
> Please swap the order in which you are doing this.
> For eMMC4.41, we can save the mmc_read_bkops_status atleast for 4.41 card
> for _every_ request, which is not used.
If card is eMMC4.41, how did you check bkops-status?
In eMCM4.41, also check the bkops-status level.
>
>> +
>> + 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
>> @@ -2382,6 +2542,12 @@ 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);
>> + }
>> + cancel_delayed_work_sync(&host->start_bkops);
>>
>> spin_lock_irqsave(&host->lock, flags);
>> host->rescan_disable = 1;
>> diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
>> index 91c84c7..3b6a8e4 100644
>> --- a/drivers/mmc/core/host.c
>> +++ b/drivers/mmc/core/host.c
>> @@ -330,6 +330,7 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
>> spin_lock_init(&host->lock);
>> init_waitqueue_head(&host->wq);
>> INIT_DELAYED_WORK(&host->detect, mmc_rescan);
>> + INIT_DELAYED_WORK(&host->start_bkops, mmc_start_periodic_bkops);
>> #ifdef CONFIG_PM
>> host->pm_notify.notifier_call = mmc_pm_notify;
>> #endif
>> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
>> index 2f0e11c..275555a 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);
>
> I am not too comfortable tying a OTP register setting to a host
> controller capability.
> What if I had multiple instances of MMC and reuse the same HC, and
> each needs a different
> setting ? Or the same HC used in multiple SoCs ?
> A sysfs entry would be better - program the INIT when a user
> explicitly sets "enable_bkops" for the device
> that is being used.
Actually, at first time i didn't consider whether bkops is enabled or not.
Some card can be disabled for bkops enable bit.
If INIT_BKOPS is set, user didn't consider whether bkops is enabled or not.
because that's set to enable.
Right, this is used sysfs..but I think it's problem what is prefrence..
>
>> + if (err)
>> + pr_warning("%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..bc8da17 100644
>> --- a/drivers/mmc/core/mmc_ops.c
>> +++ b/drivers/mmc/core/mmc_ops.c
>> @@ -399,6 +399,10 @@ 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);
>> diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
>> index d76513b..52b507d 100644
>> --- a/include/linux/mmc/card.h
>> +++ b/include/linux/mmc/card.h
>> @@ -76,6 +76,9 @@ 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 */
>> + u8 raw_exception_status; /* 53 */
>> 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 */
>> @@ -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..c920250 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 *);
>> @@ -163,6 +166,8 @@ 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_periodic_bkops(struct work_struct *work);
>> +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 0707d22..186d146 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;
>> @@ -320,6 +322,8 @@ struct mmc_host {
>>
>> unsigned int actual_clock; /* Actual HC clock rate */
>>
>> + struct delayed_work start_bkops; /* Periodic bkops start */
>> +
>> unsigned long private[0] ____cacheline_aligned;
>> };
>>
>> diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
>> index d425cab..06afeb4 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 +392,18 @@ 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
>> +#define EXT_CSD_BKOPS_LEVEL_3 0x3
>> +
>> +/*
>> + * 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 */
>
>
> Overall, my significant concern is about performance.
> IIUC, There is a ext_csd query during the execution of _every_ request
> - this is far too obsessive and could kill throughput.
I didn't find the performance issue. didn't _every_ request..only check to set bkops_need_check.
> A more pragmatic approach would be to trigger on a threshold of number
> of writes or discards (ex: After 1M sector writes)
I will try to this approach.
> This means that a predominantly read only disk, which wouldn't need
> any BKOPS, wouldn't have any overhead.
>
> Let me know if my assumption is incorrect.
Thanks for reviwe.
Best Regards,
Jaehoon Chung
>
> ~Venkat.
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