RE: [PATCH RESEND v7 2/3] mmc: core: Support packed write command for eMMC4.5 device

Subhash Jadavani
2012-06-28T09:12:19Z

Hi Seugwon, Saugata,

Here the actual large sector size support had one issue and anyway as of now
large sector size is not supported on any of the eMMC4.5 devices, whereas
the packed commands are already supported on eMMC4.5 chips so I would prefer
not to hold this patch for issue which is really not created in this patch.

Is this ok?

Regards,
Subhash

> -----Original Message-----
> From: Seungwon Jeon [mailto:tgih.jun@samsung.com]
> Sent: Thursday, June 28, 2012 1:22 PM
> To: 'Saugata Das'
> Cc: 'Subhash Jadavani'; linux-mmc@vger.kernel.org; linux-
> kernel@vger.kernel.org; 'Chris Ball'; 'Maya Erez'; 'S, Venkatraman'
> Subject: RE: [PATCH RESEND v7 2/3] mmc: core: Support packed write
> command for eMMC4.5 device
>
> Saugata Das <saugata.das@linaro.org> wrote:
> > On 26 June 2012 09:18, Seungwon Jeon <tgih.jun@samsung.com> wrote:
> > > Hi Subhash,
> > >
> > > Subhash Jadavani <subhashj@codeaurora.org> wrote:
> > >> Hi Seungwon,
> > >>
> > >> Please one comment inline below related to large sector size handling
for
> packed commands.
> > >>
> > >> Regards,
> > >> Subhash
> > >>
> > >> > -----Original Message-----
> > >> > From: linux-mmc-owner@vger.kernel.org [mailto:linux-mmc-
> > >> > owner@vger.kernel.org] On Behalf Of Seungwon Jeon
> > >> > Sent: Monday, June 18, 2012 11:13 AM
> > >> > To: linux-mmc@vger.kernel.org
> > >> > Cc: linux-kernel@vger.kernel.org; 'Chris Ball'; 'Maya Erez';
> > >> > 'Subhash Jadavani'; 'S, Venkatraman'
> > >> > Subject: [PATCH RESEND v7 2/3] mmc: core: Support packed write
> > >> > command for eMMC4.5 device
> > >> >
> > >> > This patch supports packed write command of eMMC4.5 device.
> > >> > Several writes can be grouped in packed command and all data of
> > >> > the individual commands can be sent in a single transfer on the
bus.
> > >> >
> > >> > Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
> > >> > ---
> > >> >  drivers/mmc/card/block.c   |  406
> > >> > +++++++++++++++++++++++++++++++++++++++++---
> > >> >  drivers/mmc/card/queue.c   |   45 +++++-
> > >> >  drivers/mmc/card/queue.h   |   12 ++
> > >> >  drivers/mmc/core/mmc_ops.c |    1 +
> > >> >  include/linux/mmc/core.h   |    4 +
> > >> >  5 files changed, 441 insertions(+), 27 deletions(-)
> > >> >
> > >> > diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
> > >> > index
> > >> > 7e3f453..eb99e35 100644
> > >> > --- a/drivers/mmc/card/block.c
> > >> > +++ b/drivers/mmc/card/block.c
> > >> > @@ -58,6 +58,12 @@ MODULE_ALIAS("mmc:block");  #define
> > >> > INAND_CMD38_ARG_SECTRIM1 0x81  #define
> INAND_CMD38_ARG_SECTRIM2
> > >> > 0x88
> > >> >
> > >> > +#define mmc_req_rel_wr(req)        (((req->cmd_flags & REQ_FUA)
> > >> > +|| \
> > >> > +                   (req->cmd_flags & REQ_META)) && \
> > >> > +                   (rq_data_dir(req) == WRITE)) #define
> > >> > +PACKED_CMD_VER             0x01 #define PACKED_CMD_WR
> > >> > +0x02
> > >> > +
> > >> >  static DEFINE_MUTEX(block_mutex);
> > >> >
> > >> >  /*
> > >> > @@ -123,9 +129,21 @@ enum mmc_blk_status {
> > >> >     MMC_BLK_NOMEDIUM,
> > >> >  };
> > >> >
> > >> > +enum {
> > >> > +   MMC_PACKED_N_IDX = -1,
> > >> > +   MMC_PACKED_N_ZERO,
> > >> > +   MMC_PACKED_N_SINGLE,
> > >> > +};
> > >> > +
> > >> >  module_param(perdev_minors, int, 0444);
> > >> > MODULE_PARM_DESC(perdev_minors, "Minors numbers to allocate per
> > >> > device");
> > >> >
> > >> > +static inline void mmc_blk_clear_packed(struct mmc_queue_req
> > >> > +*mqrq) {
> > >> > +   mqrq->packed_cmd = MMC_PACKED_NONE;
> > >> > +   mqrq->packed_num = MMC_PACKED_N_ZERO; }
> > >> > +
> > >> >  static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk)  {
> > >> >     struct mmc_blk_data *md;
> > >> > @@ -1081,12 +1099,61 @@ static int mmc_blk_err_check(struct
> > >> > mmc_card *card,
> > >> >     if (!brq->data.bytes_xfered)
> > >> >             return MMC_BLK_RETRY;
> > >> >
> > >> > +   if (mq_mrq->packed_cmd != MMC_PACKED_NONE) {
> > >> > +           if (unlikely(brq->data.blocks << 9 !=
> > >> > + brq->data.bytes_xfered))
> > >> > +                   return MMC_BLK_PARTIAL;
> > >> > +           else
> > >> > +                   return MMC_BLK_SUCCESS;
> > >> > +   }
> > >> > +
> > >> >     if (blk_rq_bytes(req) != brq->data.bytes_xfered)
> > >> >             return MMC_BLK_PARTIAL;
> > >> >
> > >> >     return MMC_BLK_SUCCESS;
> > >> >  }
> > >> >
> > >> > +static int mmc_blk_packed_err_check(struct mmc_card *card,
> > >> > +                               struct mmc_async_req *areq) {
> > >> > +   struct mmc_queue_req *mq_rq = container_of(areq, struct
> > >> > mmc_queue_req,
> > >> > +                   mmc_active);
> > >> > +   struct request *req = mq_rq->req;
> > >> > +   int err, check, status;
> > >> > +   u8 ext_csd[512];
> > >> > +
> > >> > +   mq_rq->packed_retries--;
> > >> > +   check = mmc_blk_err_check(card, areq);
> > >> > +   err = get_card_status(card, &status, 0);
> > >> > +   if (err) {
> > >> > +           pr_err("%s: error %d sending status command\n",
> > >> > +                           req->rq_disk->disk_name, err);
> > >> > +           return MMC_BLK_ABORT;
> > >> > +   }
> > >> > +
> > >> > +   if (status & R1_EXP_EVENT) {
> > >> > +           err = mmc_send_ext_csd(card, ext_csd);
> > >> > +           if (err) {
> > >> > +                   pr_err("%s: error %d sending ext_csd\n",
> > >> > +                                   req->rq_disk->disk_name,
> > >> > + err);
> > >> > +                   return MMC_BLK_ABORT;
> > >> > +           }
> > >> > +
> > >> > +           if ((ext_csd[EXT_CSD_EXP_EVENTS_STATUS] &
> > >> > +                                   EXT_CSD_PACKED_FAILURE) &&
> > >> > +                           (ext_csd[EXT_CSD_PACKED_CMD_STATUS] &
> > >> > +                            EXT_CSD_PACKED_GENERIC_ERROR)) {
> > >> > +                   if (ext_csd[EXT_CSD_PACKED_CMD_STATUS] &
> > >> > +                                   EXT_CSD_PACKED_INDEXED_ERROR)
> > >> > + {
> > >> > +                           mq_rq->packed_fail_idx =
> > >> > +
> > >> > + ext_csd[EXT_CSD_PACKED_FAILURE_INDEX] -
> > >> > 1;
> > >> > +                           return MMC_BLK_PARTIAL;
> > >> > +                   }
> > >> > +           }
> > >> > +   }
> > >> > +
> > >> > +   return check;
> > >> > +}
> > >> > +
> > >> >  static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq,
> > >> >                            struct mmc_card *card,
> > >> >                            int disable_multi, @@ -1241,10
> > >> > +1308,197 @@ static void mmc_blk_rw_rq_prep(struct
> mmc_queue_req
> > >> > *mqrq,
> > >> >     mmc_queue_bounce_pre(mqrq);
> > >> >  }
> > >> >
> > >> > +static u8 mmc_blk_prep_packed_list(struct mmc_queue *mq, struct
> > >> > +request
> > >> > +*req) {
> > >> > +   struct request_queue *q = mq->queue;
> > >> > +   struct mmc_card *card = mq->card;
> > >> > +   struct request *cur = req, *next = NULL;
> > >> > +   struct mmc_blk_data *md = mq->data;
> > >> > +   bool en_rel_wr = card->ext_csd.rel_param &
> > >> > EXT_CSD_WR_REL_PARAM_EN;
> > >> > +   unsigned int req_sectors = 0, phys_segments = 0;
> > >> > +   unsigned int max_blk_count, max_phys_segs;
> > >> > +   u8 put_back = 0;
> > >> > +   u8 max_packed_rw = 0;
> > >> > +   u8 reqs = 0;
> > >> > +
> > >> > +   mmc_blk_clear_packed(mq->mqrq_cur);
> > >> > +
> > >> > +   if (!(md->flags & MMC_BLK_CMD23) ||
> > >> > +                   !card->ext_csd.packed_event_en)
> > >> > +           goto no_packed;
> > >> > +
> > >> > +   if ((rq_data_dir(cur) == WRITE) &&
> > >> > +                   (card->host->caps2 & MMC_CAP2_PACKED_WR))
> > >> > +           max_packed_rw = card->ext_csd.max_packed_writes;
> > >> > +
> > >> > +   if (max_packed_rw == 0)
> > >> > +           goto no_packed;
> > >> > +
> > >> > +   if (mmc_req_rel_wr(cur) &&
> > >> > +                   (md->flags & MMC_BLK_REL_WR) &&
> > >> > +                   !en_rel_wr) {
> > >> > +           goto no_packed;
> > >> > +   }
> > >> > +
> > >> > +   max_blk_count = min(card->host->max_blk_count,
> > >> > +                   card->host->max_req_size >> 9);
> > >> > +   if (unlikely(max_blk_count > 0xffff))
> > >> > +           max_blk_count = 0xffff;
> > >> > +
> > >> > +   max_phys_segs = queue_max_segments(q);
> > >> > +   req_sectors += blk_rq_sectors(cur);
> > >> > +   phys_segments += cur->nr_phys_segments;
> > >> > +
> > >> > +   if (rq_data_dir(cur) == WRITE) {
> > >> > +           req_sectors++;
> > >> > +           phys_segments++;
> > >> > +   }
> > >> > +
> > >> > +   while (reqs < max_packed_rw - 1) {
> > >> > +           spin_lock_irq(q->queue_lock);
> > >> > +           next = blk_fetch_request(q);
> > >> > +           spin_unlock_irq(q->queue_lock);
> > >> > +           if (!next)
> > >> > +                   break;
> > >> > +
> > >> > +           if (next->cmd_flags & REQ_DISCARD ||
> > >> > +                           next->cmd_flags & REQ_FLUSH) {
> > >> > +                   put_back = 1;
> > >> > +                   break;
> > >> > +           }
> > >> > +
> > >> > +           if (rq_data_dir(cur) != rq_data_dir(next)) {
> > >> > +                   put_back = 1;
> > >> > +                   break;
> > >> > +           }
> > >> > +
> > >> > +           if (mmc_req_rel_wr(next) &&
> > >> > +                           (md->flags & MMC_BLK_REL_WR) &&
> > >> > +                           !en_rel_wr) {
> > >> > +                   put_back = 1;
> > >> > +                   break;
> > >> > +           }
> > >> > +
> > >> > +           req_sectors += blk_rq_sectors(next);
> > >> > +           if (req_sectors > max_blk_count) {
> > >> > +                   put_back = 1;
> > >> > +                   break;
> > >> > +           }
> > >> > +
> > >> > +           phys_segments +=  next->nr_phys_segments;
> > >> > +           if (phys_segments > max_phys_segs) {
> > >> > +                   put_back = 1;
> > >> > +                   break;
> > >> > +           }
> > >> > +
> > >> > +           list_add_tail(&next->queuelist,
> > >> > + &mq->mqrq_cur->packed_list);
> > >> > +           cur = next;
> > >> > +           reqs++;
> > >> > +   }
> > >> > +
> > >> > +   if (put_back) {
> > >> > +           spin_lock_irq(q->queue_lock);
> > >> > +           blk_requeue_request(q, next);
> > >> > +           spin_unlock_irq(q->queue_lock);
> > >> > +   }
> > >> > +
> > >> > +   if (reqs > 0) {
> > >> > +           list_add(&req->queuelist,
> > >> > + &mq->mqrq_cur->packed_list);
> > >> > +           mq->mqrq_cur->packed_num = ++reqs;
> > >> > +           mq->mqrq_cur->packed_retries = reqs;
> > >> > +           return reqs;
> > >> > +   }
> > >> > +
> > >> > +no_packed:
> > >> > +   mmc_blk_clear_packed(mq->mqrq_cur);
> > >> > +   return 0;
> > >> > +}
> > >> > +
> > >> > +static void mmc_blk_packed_hdr_wrq_prep(struct mmc_queue_req
> > >> > +*mqrq,
> > >> > +                                   struct mmc_card *card,
> > >> > +                                   struct mmc_queue *mq) {
> > >> > +   struct mmc_blk_request *brq = &mqrq->brq;
> > >> > +   struct request *req = mqrq->req;
> > >> > +   struct request *prq;
> > >> > +   struct mmc_blk_data *md = mq->data;
> > >> > +   bool do_rel_wr, do_data_tag;
> > >> > +   u32 *packed_cmd_hdr = mqrq->packed_cmd_hdr;
> > >> > +   u8 i = 1;
> > >> > +
> > >> > +   mqrq->packed_cmd = MMC_PACKED_WRITE;
> > >> > +   mqrq->packed_blocks = 0;
> > >> > +   mqrq->packed_fail_idx = MMC_PACKED_N_IDX;
> > >> > +
> > >> > +   memset(packed_cmd_hdr, 0, sizeof(mqrq->packed_cmd_hdr));
> > >> > +   packed_cmd_hdr[0] = (mqrq->packed_num << 16) |
> > >> > +           (PACKED_CMD_WR << 8) | PACKED_CMD_VER;
> > >> > +
> > >> > +   /*
> > >> > +    * Argument for each entry of packed group
> > >> > +    */
> > >> > +   list_for_each_entry(prq, &mqrq->packed_list, queuelist) {
> > >> > +           do_rel_wr = mmc_req_rel_wr(prq) && (md->flags &
> > >> > MMC_BLK_REL_WR);
> > >> > +           do_data_tag = (card->ext_csd.data_tag_unit_size) &&
> > >> > +                   (prq->cmd_flags & REQ_META) &&
> > >> > +                   (rq_data_dir(prq) == WRITE) &&
> > >> > +                   ((brq->data.blocks * brq->data.blksz) >=
> > >> > +                    card->ext_csd.data_tag_unit_size);
> > >> > +           /* Argument of CMD23 */
> > >> > +           packed_cmd_hdr[(i * 2)] =
> > >> > +                   (do_rel_wr ? MMC_CMD23_ARG_REL_WR : 0) |
> > >> > +                   (do_data_tag ? MMC_CMD23_ARG_TAG_REQ : 0) |
> > >> > +                   blk_rq_sectors(prq);
> > >> > +           /* Argument of CMD18 or CMD25 */
> > >> > +           packed_cmd_hdr[((i * 2)) + 1] =
> > >> > +                   mmc_card_blockaddr(card) ?
> > >> > +                   blk_rq_pos(prq) : blk_rq_pos(prq) << 9;
> > >> > +           mqrq->packed_blocks += blk_rq_sectors(prq);
> > >> > +           i++;
> > >> > +   }
> > >> > +
> > >> > +   memset(brq, 0, sizeof(struct mmc_blk_request));
> > >> > +   brq->mrq.cmd = &brq->cmd;
> > >> > +   brq->mrq.data = &brq->data;
> > >> > +   brq->mrq.sbc = &brq->sbc;
> > >> > +   brq->mrq.stop = &brq->stop;
> > >> > +
> > >> > +   brq->sbc.opcode = MMC_SET_BLOCK_COUNT;
> > >> > +   brq->sbc.arg = MMC_CMD23_ARG_PACKED | (mqrq->packed_blocks
> +
> > >> > 1);
> > >> > +   brq->sbc.flags = MMC_RSP_R1 | MMC_CMD_AC;
> > >> > +
> > >> > +   brq->cmd.opcode = MMC_WRITE_MULTIPLE_BLOCK;
> > >> > +   brq->cmd.arg = blk_rq_pos(req);
> > >> > +   if (!mmc_card_blockaddr(card))
> > >> > +           brq->cmd.arg <<= 9;
> > >> > +   brq->cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 |
> > >> > MMC_CMD_ADTC;
> > >> > +
> > >> > +   brq->data.blksz = 512;
> > >> > +   brq->data.blocks = mqrq->packed_blocks + 1;
> > >> > +   brq->data.flags |= MMC_DATA_WRITE;
> > >> > +
> > >> > +   brq->stop.opcode = MMC_STOP_TRANSMISSION;
> > >> > +   brq->stop.arg = 0;
> > >> > +   brq->stop.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B |
> > >> > MMC_CMD_AC;
> > >> > +
> > >> > +   mmc_set_data_timeout(&brq->data, card);
> > >> > +
> > >> > +   brq->data.sg = mqrq->sg;
> > >> > +   brq->data.sg_len = mmc_queue_map_sg(mq, mqrq);
> > >> > +
> > >> > +   mqrq->mmc_active.mrq = &brq->mrq;
> > >> > +   mqrq->mmc_active.err_check = mmc_blk_packed_err_check;
> > >> > +
> > >> > +   mmc_queue_bounce_pre(mqrq);
> > >> > +}
> > >> > +
> > >> >  static int mmc_blk_cmd_err(struct mmc_blk_data *md, struct
> > >> > mmc_card *card,
> > >> >                        struct mmc_blk_request *brq, struct
> > >> > request *req,
> > >> >                        int ret)
> > >> >  {
> > >> > +   struct mmc_queue_req *mq_rq;
> > >> > +   mq_rq = container_of(brq, struct mmc_queue_req, brq);
> > >> > +
> > >> >     /*
> > >> >      * If this is an SD card and we're writing, we can first
> > >> >      * mark the known good sectors as ok.
> > >> > @@ -1261,10 +1515,73 @@ static int mmc_blk_cmd_err(struct
> > >> > mmc_blk_data *md, struct mmc_card *card,
> > >> >                     ret = blk_end_request(req, 0, blocks << 9);
> > >> >             }
> > >> >     } else {
> > >> > -           ret = blk_end_request(req, 0,
> > >> > brq->data.bytes_xfered);
> > >> > +           if (mq_rq->packed_cmd == MMC_PACKED_NONE)
> > >> > +                   ret = blk_end_request(req, 0,
> > >> > +brq->data.bytes_xfered);
> > >> > +   }
> > >> > +   return ret;
> > >> > +}
> > >> > +
> > >> > +static int mmc_blk_end_packed_req(struct mmc_queue_req *mq_rq) {
> > >> > +   struct request *prq;
> > >> > +   int idx = mq_rq->packed_fail_idx, i = 0;
> > >> > +   int ret = 0;
> > >> > +
> > >> > +   while (!list_empty(&mq_rq->packed_list)) {
> > >> > +           prq = list_entry_rq(mq_rq->packed_list.next);
> > >> > +           if (idx == i) {
> > >> > +                   /* retry from error index */
> > >> > +                   mq_rq->packed_num -= idx;
> > >> > +                   mq_rq->req = prq;
> > >> > +                   ret = 1;
> > >> > +
> > >> > +                   if (mq_rq->packed_num == MMC_PACKED_N_SINGLE)
> > >> > {
> > >> > +                           list_del_init(&prq->queuelist);
> > >> > +                           mmc_blk_clear_packed(mq_rq);
> > >> > +                   }
> > >> > +                   return ret;
> > >> > +           }
> > >> > +           list_del_init(&prq->queuelist);
> > >> > +           blk_end_request(prq, 0, blk_rq_bytes(prq));
> > >> > +           i++;
> > >> >     }
> > >> > +
> > >> > +   mmc_blk_clear_packed(mq_rq);
> > >> >     return ret;
> > >> >  }
> > >> > +static void mmc_blk_abort_packed_req(struct mmc_queue_req
> > >> > +*mq_rq) {
> > >> > +   struct request *prq;
> > >> > +
> > >> > +   while (!list_empty(&mq_rq->packed_list)) {
> > >> > +           prq = list_entry_rq(mq_rq->packed_list.next);
> > >> > +           list_del_init(&prq->queuelist);
> > >> > +           blk_end_request(prq, -EIO, blk_rq_bytes(prq));
> > >> > +   }
> > >> > +
> > >> > +   mmc_blk_clear_packed(mq_rq);
> > >> > +}
> > >> > +
> > >> > +static void mmc_blk_revert_packed_req(struct mmc_queue *mq,
> > >> > +                                 struct mmc_queue_req *mq_rq) {
> > >> > +   struct request *prq;
> > >> > +   struct request_queue *q = mq->queue;
> > >> > +
> > >> > +   while (!list_empty(&mq_rq->packed_list)) {
> > >> > +           prq = list_entry_rq(mq_rq->packed_list.prev);
> > >> > +           if (prq->queuelist.prev != &mq_rq->packed_list) {
> > >> > +                   list_del_init(&prq->queuelist);
> > >> > +                   spin_lock_irq(q->queue_lock);
> > >> > +                   blk_requeue_request(mq->queue, prq);
> > >> > +                   spin_unlock_irq(q->queue_lock);
> > >> > +           } else {
> > >> > +                   list_del_init(&prq->queuelist);
> > >> > +           }
> > >> > +   }
> > >> > +
> > >> > +   mmc_blk_clear_packed(mq_rq);
> > >> > +}
> > >> >
> > >> >  static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct
> > >> > request *rqc) { @@ -1276,23 +1593,35 @@ static int
> > >> > mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *rqc)
> > >> >     struct mmc_queue_req *mq_rq;
> > >> >     struct request *req = rqc;
> > >> >     struct mmc_async_req *areq;
> > >> > +   const u8 packed_num = 2;
> > >> > +   u8 reqs = 0;
> > >> >
> > >> >     if (!rqc && !mq->mqrq_prev->req)
> > >> >             return 0;
> > >> >
> > >> > +   if (rqc) {
> > >> > +           /*
> > >> > +            * When 4KB native sector is enabled, only 8 blocks
> > >> > +            * multiple read or write is allowed
> > >> > +            */
> > >> > +           if ((brq->data.blocks & 0x07) &&
> > >>
> > >> What will be the value of "brq->data.blocks" here? I don't think
> > >> this has been even initialized
> > here.
> > > Right, "brq->data.blocks" doesn't have the value.
> > > This have been already introduced in "mmc: block: Allow disabling 512B
> sector size emulation"
> > > but it seems to have the same problem. I'll fix this for next version.
> >
> > Thanks for pointing it out.
> >
> > Should I submit the correction for this part separately (changing
> > (brq->data.blocks & 0x07) to (blk_rq_sectors(req) & 0x07) ?
> Course you can. I'm waiting.
>
> Thanks,
> Seungwon Jeon
> >
> >
> > >
> > >> Also this is what specification (6.6.30.2  Native 4KB sector
> > >> behavior) mandates for large sector
> > size
> > >> native:
> > >>       - Sector counts shall be multiples of 8 (4KB), e.g. in
> > >> SET_BLOCK_COUNT (CMD23), and CORRECTLY_PRG_SECTORS_NUM field
> in
> > >> EXT_CSD
> > >>       - Arguments for read commands (CMD17/18) and write commands
> > >> (CMD24/25) shall always be aligned to 8 (4KB)
> > >>
> > >> So for each entry (which is for each request) in packed command
> > >> header, you need to make sure that sector count is in multiple of 8
> > >> for CMD23 argument and also CMD18/CMD25 arguments (sector
> address) must be 4KB aligned.
> > > I'll also apply this.
> > >
> > > Best regard,
> > > Seungwon Jeon
> > >>
> > >> Regards,
> > >> Subhash
> > >>
> > >> > +                           (card->ext_csd.data_sector_size ==
> > >> > + 4096)) {
> > >> > +                   pr_err("%s: Transfer size is not 4KB sector
> > >> > + size
> > >> > aligned\n",
> > >> > +                                   req->rq_disk->disk_name);
> > >> > +                   mq_rq = mq->mqrq_cur;
> > >> > +                   goto cmd_abort;
> > >> > +           }
> > >> > +
> > >> > +           reqs = mmc_blk_prep_packed_list(mq, rqc);
> > >> > +   }
> > >> > +
> > >> >     do {
> > >> >             if (rqc) {
> > >> > -                   /*
> > >> > -                    * When 4KB native sector is enabled, only 8
> > >> > blocks
> > >> > -                    * multiple read or write is allowed
> > >> > -                    */
> > >> > -                   if ((brq->data.blocks & 0x07) &&
> > >> > -                       (card->ext_csd.data_sector_size == 4096))
> > >> > {
> > >> > -                           pr_err("%s: Transfer size is not 4KB
> > >> > sector size aligned\n",
> > >> > -                                   req->rq_disk->disk_name);
> > >> > -                           goto cmd_abort;
> > >> > -                   }
> > >> > -                   mmc_blk_rw_rq_prep(mq->mqrq_cur, card, 0,
> > >> > mq);
> > >> > +                   if (reqs >= packed_num)
> > >> > +                           mmc_blk_packed_hdr_wrq_prep(mq-
> > >> > >mqrq_cur,
> > >> > +                                           card, mq);
> > >> > +                   else
> > >> > +                           mmc_blk_rw_rq_prep(mq->mqrq_cur,
> > >> > + card, 0,
> > >> > mq);
> > >> >                     areq = &mq->mqrq_cur->mmc_active;
> > >> >             } else
> > >> >                     areq = NULL;
> > >> > @@ -1313,8 +1642,15 @@ static int mmc_blk_issue_rw_rq(struct
> > >> > mmc_queue *mq, struct request *rqc)
> > >> >                      * A block was successfully transferred.
> > >> >                      */
> > >> >                     mmc_blk_reset_success(md, type);
> > >> > -                   ret = blk_end_request(req, 0,
> > >> > +
> > >> > +                   if (mq_rq->packed_cmd != MMC_PACKED_NONE) {
> > >> > +                           ret = mmc_blk_end_packed_req(mq_rq);
> > >> > +                           break;
> > >> > +                   } else {
> > >> > +                           ret = blk_end_request(req, 0,
> > >> >
> > >> > brq->data.bytes_xfered);
> > >> > +                   }
> > >> > +
> > >> >                     /*
> > >> >                      * If the blk_end_request function returns
> > >> > non-zero even
> > >> >                      * though all data has been transferred and
> > >> > no errors @@ -1347,7 +1683,8 @@ static int
> > >> > mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *rqc)
> > >> >                     err = mmc_blk_reset(md, card->host, type);
> > >> >                     if (!err)
> > >> >                             break;
> > >> > -                   if (err == -ENODEV)
> > >> > +                   if (err == -ENODEV ||
> > >> > +                           mq_rq->packed_cmd !=
> > >> > MMC_PACKED_NONE)
> > >> >                             goto cmd_abort;
> > >> >                     /* Fall through */
> > >> >             }
> > >> > @@ -1374,25 +1711,46 @@ static int mmc_blk_issue_rw_rq(struct
> > >> > mmc_queue *mq, struct request *rqc)
> > >> >             }
> > >> >
> > >> >             if (ret) {
> > >> > -                   /*
> > >> > -                    * In case of a incomplete request
> > >> > -                    * prepare it again and resend.
> > >> > -                    */
> > >> > -                   mmc_blk_rw_rq_prep(mq_rq, card,
> > >> > disable_multi, mq);
> > >> > -                   mmc_start_req(card->host, &mq_rq->mmc_active,
> > >> > NULL);
> > >> > +                   if (mq_rq->packed_cmd == MMC_PACKED_NONE) {
> > >> > +                           /*
> > >> > +                            * In case of a incomplete request
> > >> > +                            * prepare it again and resend.
> > >> > +                            */
> > >> > +                           mmc_blk_rw_rq_prep(mq_rq, card,
> > >> > +                                           disable_multi, mq);
> > >> > +                           mmc_start_req(card->host,
> > >> > +                                           &mq_rq->mmc_active,
> > >> > + NULL);
> > >> > +                   } else {
> > >> > +                           if (!mq_rq->packed_retries)
> > >> > +                                   goto cmd_abort;
> > >> > +                           mmc_blk_packed_hdr_wrq_prep(mq_rq,
> > >> > + card,
> > >> > mq);
> > >> > +                           mmc_start_req(card->host,
> > >> > +                                           &mq_rq->mmc_active,
> > >> > + NULL);
> > >> > +                   }
> > >> >             }
> > >> >     } while (ret);
> > >> >
> > >> >     return 1;
> > >> >
> > >> >   cmd_abort:
> > >> > -   if (mmc_card_removed(card))
> > >> > -           req->cmd_flags |= REQ_QUIET;
> > >> > -   while (ret)
> > >> > -           ret = blk_end_request(req, -EIO,
> > >> > blk_rq_cur_bytes(req));
> > >> > +   if (mq_rq->packed_cmd == MMC_PACKED_NONE) {
> > >> > +           if (mmc_card_removed(card))
> > >> > +                   req->cmd_flags |= REQ_QUIET;
> > >> > +           while (ret)
> > >> > +                   ret = blk_end_request(req, -EIO,
> > >> > +                                   blk_rq_cur_bytes(req));
> > >> > +   } else {
> > >> > +           mmc_blk_abort_packed_req(mq_rq);
> > >> > +   }
> > >> >
> > >> >   start_new_req:
> > >> >     if (rqc) {
> > >> > +           /*
> > >> > +            * If current request is packed, it needs to put back.
> > >> > +            */
> > >> > +           if (mq->mqrq_cur->packed_cmd != MMC_PACKED_NONE)
> > >> > +                   mmc_blk_revert_packed_req(mq, mq->mqrq_cur);
> > >> > +
> > >> >             mmc_blk_rw_rq_prep(mq->mqrq_cur, card, 0, mq);
> > >> >             mmc_start_req(card->host, &mq->mqrq_cur->mmc_active,
> > >> > NULL);
> > >> >     }
> > >> > diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c
> > >> > index e360a97..165d85a 100644
> > >> > --- a/drivers/mmc/card/queue.c
> > >> > +++ b/drivers/mmc/card/queue.c
> > >> > @@ -175,6 +175,9 @@ int mmc_init_queue(struct mmc_queue *mq,
> > >> > struct mmc_card *card,
> > >> >     if (!mq->queue)
> > >> >             return -ENOMEM;
> > >> >
> > >> > +   INIT_LIST_HEAD(&mqrq_cur->packed_list);
> > >> > +   INIT_LIST_HEAD(&mqrq_prev->packed_list);
> > >> > +
> > >> >     mq->mqrq_cur = mqrq_cur;
> > >> >     mq->mqrq_prev = mqrq_prev;
> > >> >     mq->queue->queuedata = mq;
> > >> > @@ -375,6 +378,35 @@ void mmc_queue_resume(struct mmc_queue
> *mq)
> > >> >     }
> > >> >  }
> > >> >
> > >> > +static unsigned int mmc_queue_packed_map_sg(struct mmc_queue
> > >> > +*mq,
> > >> > +                                       struct mmc_queue_req
> > >> > +*mqrq,
> > >> > +                                       struct scatterlist *sg) {
> > >> > +   struct scatterlist *__sg;
> > >> > +   unsigned int sg_len = 0;
> > >> > +   struct request *req;
> > >> > +   enum mmc_packed_cmd cmd;
> > >> > +
> > >> > +   cmd = mqrq->packed_cmd;
> > >> > +
> > >> > +   if (cmd == MMC_PACKED_WRITE) {
> > >> > +           __sg = sg;
> > >> > +           sg_set_buf(__sg, mqrq->packed_cmd_hdr,
> > >> > +                           sizeof(mqrq->packed_cmd_hdr));
> > >> > +           sg_len++;
> > >> > +           __sg->page_link &= ~0x02;
> > >> > +   }
> > >> > +
> > >> > +   __sg = sg + sg_len;
> > >> > +   list_for_each_entry(req, &mqrq->packed_list, queuelist) {
> > >> > +           sg_len += blk_rq_map_sg(mq->queue, req, __sg);
> > >> > +           __sg = sg + (sg_len - 1);
> > >> > +           (__sg++)->page_link &= ~0x02;
> > >> > +   }
> > >> > +   sg_mark_end(sg + (sg_len - 1));
> > >> > +   return sg_len;
> > >> > +}
> > >> > +
> > >> >  /*
> > >> >   * Prepare the sg list(s) to be handed of to the host driver
> > >> >   */
> > >> > @@ -385,12 +417,19 @@ unsigned int mmc_queue_map_sg(struct
> > >> > mmc_queue *mq, struct mmc_queue_req *mqrq)
> > >> >     struct scatterlist *sg;
> > >> >     int i;
> > >> >
> > >> > -   if (!mqrq->bounce_buf)
> > >> > -           return blk_rq_map_sg(mq->queue, mqrq->req, mqrq->sg);
> > >> > +   if (!mqrq->bounce_buf) {
> > >> > +           if (!list_empty(&mqrq->packed_list))
> > >> > +                   return mmc_queue_packed_map_sg(mq, mqrq,
> > >> > + mqrq-
> > >> > >sg);
> > >> > +           else
> > >> > +                   return blk_rq_map_sg(mq->queue, mqrq->req,
> > >> > + mqrq-
> > >> > >sg);
> > >> > +   }
> > >> >
> > >> >     BUG_ON(!mqrq->bounce_sg);
> > >> >
> > >> > -   sg_len = blk_rq_map_sg(mq->queue, mqrq->req,
> > >> > mqrq->bounce_sg);
> > >> > +   if (!list_empty(&mqrq->packed_list))
> > >> > +           sg_len = mmc_queue_packed_map_sg(mq, mqrq, mqrq-
> > >> > >bounce_sg);
> > >> > +   else
> > >> > +           sg_len = blk_rq_map_sg(mq->queue, mqrq->req, mqrq-
> > >> > >bounce_sg);
> > >> >
> > >> >     mqrq->bounce_sg_len = sg_len;
> > >> >
> > >> > diff --git a/drivers/mmc/card/queue.h b/drivers/mmc/card/queue.h
> > >> > index
> > >> > d2a1eb4..5e04938 100644
> > >> > --- a/drivers/mmc/card/queue.h
> > >> > +++ b/drivers/mmc/card/queue.h
> > >> > @@ -12,6 +12,11 @@ struct mmc_blk_request {
> > >> >     struct mmc_data         data;
> > >> >  };
> > >> >
> > >> > +enum mmc_packed_cmd {
> > >> > +   MMC_PACKED_NONE = 0,
> > >> > +   MMC_PACKED_WRITE,
> > >> > +};
> > >> > +
> > >> >  struct mmc_queue_req {
> > >> >     struct request          *req;
> > >> >     struct mmc_blk_request  brq;
> > >> > @@ -20,6 +25,13 @@ struct mmc_queue_req {
> > >> >     struct scatterlist      *bounce_sg;
> > >> >     unsigned int            bounce_sg_len;
> > >> >     struct mmc_async_req    mmc_active;
> > >> > +   struct list_head        packed_list;
> > >> > +   u32                     packed_cmd_hdr[128];
> > >> > +   unsigned int            packed_blocks;
> > >> > +   enum mmc_packed_cmd     packed_cmd;
> > >> > +   int             packed_retries;
> > >> > +   int             packed_fail_idx;
> > >> > +   u8              packed_num;
> > >> >  };
> > >> >
> > >> >  struct mmc_queue {
> > >> > diff --git a/drivers/mmc/core/mmc_ops.c
> > >> > b/drivers/mmc/core/mmc_ops.c index 69370f4..2a2fed8 100644
> > >> > --- a/drivers/mmc/core/mmc_ops.c
> > >> > +++ b/drivers/mmc/core/mmc_ops.c
> > >> > @@ -335,6 +335,7 @@ int mmc_send_ext_csd(struct mmc_card *card,
> > >> > u8
> > >> > *ext_csd)
> > >> >     return mmc_send_cxd_data(card, card->host, MMC_SEND_EXT_CSD,
> > >> >                     ext_csd, 512);
> > >> >  }
> > >> > +EXPORT_SYMBOL_GPL(mmc_send_ext_csd);
> > >> >
> > >> >  int mmc_spi_read_ocr(struct mmc_host *host, int highcap, u32
> > >> > *ocrp)  { diff -- git a/include/linux/mmc/core.h
> > >> > b/include/linux/mmc/core.h index
> > >> > 1b431c7..d787037 100644
> > >> > --- a/include/linux/mmc/core.h
> > >> > +++ b/include/linux/mmc/core.h
> > >> > @@ -18,6 +18,9 @@ struct mmc_request;
> > >> >  struct mmc_command {
> > >> >     u32                     opcode;
> > >> >     u32                     arg;
> > >> > +#define MMC_CMD23_ARG_REL_WR       (1 << 31) #define
> > >> > +MMC_CMD23_ARG_PACKED       ((0 << 31) | (1 << 30)) #define
> > >> > +MMC_CMD23_ARG_TAG_REQ      (1 << 29)
> > >> >     u32                     resp[4];
> > >> >     unsigned int            flags;          /* expected response
> > >> > type */
> > >> >  #define MMC_RSP_PRESENT    (1 << 0) @@ -143,6 +146,7 @@ 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 int mmc_switch(struct mmc_card *, u8, u8, u8, unsigned
> > >> > int);
> > >> > +extern int mmc_send_ext_csd(struct mmc_card *card, u8 *ext_csd);
> > >> >
> > >> >  #define MMC_ERASE_ARG              0x00000000
> > >> >  #define MMC_SECURE_ERASE_ARG       0x80000000
> > >> > --
> > >> > 1.7.0.4
> > >> >
> > >> >
> > >> > --
> > >> > To unsubscribe from this list: send the line "unsubscribe
> > >> > linux-mmc" in the body of a message to majordomo@vger.kernel.org
> > >> > 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 majordomo@vger.kernel.org
> > >> 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 majordomo@vger.kernel.org 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 majordomo@vger.kernel.org More majordomo
> > info at http://vger.kernel.org/majordomo-info.html