From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753816Ab2FZIt1 (ORCPT ); Tue, 26 Jun 2012 04:49:27 -0400 Received: from na3sys009aog130.obsmtp.com ([74.125.149.143]:53349 "EHLO na3sys009aog130.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751313Ab2FZItY convert rfc822-to-8bit (ORCPT ); Tue, 26 Jun 2012 04:49:24 -0400 MIME-Version: 1.0 In-Reply-To: <007b01cd4d15$40673510$c1359f30$%jun@samsung.com> References: <007b01cd4d15$40673510$c1359f30$%jun@samsung.com> From: "S, Venkatraman" Date: Tue, 26 Jun 2012 14:19:00 +0530 Message-ID: Subject: Re: [PATCH RESEND v7 2/3] mmc: core: Support packed write command for eMMC4.5 device To: Seungwon Jeon Cc: linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, Chris Ball , Maya Erez , Subhash Jadavani Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 18, 2012 at 11:13 AM, Seungwon Jeon wrote: > 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 > --- >  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; ^^ This means that the number of times the packed command is retried is equal to the number of requests it packs ? How are they related ? > +               return reqs; > +       } > + > +no_packed: > +       mmc_blk_clear_packed(mq->mqrq_cur); > +       return 0; > +} > +