Allows device MMC boot partitions to be accessed. MMC partitions
are treated effectively as separate block devices on the same
MMC card.

Signed-off-by: Andrei Warkentin <andr...@motorola.com>
---
 drivers/mmc/card/Kconfig   |   18 ++++
 drivers/mmc/card/block.c   |  208 +++++++++++++++++++++++++++++++++++---------
 drivers/mmc/core/mmc.c     |    5 +
 drivers/mmc/core/mmc_ops.h |    1 -
 include/linux/mmc/card.h   |    2 +
 include/linux/mmc/core.h   |    1 +
 include/linux/mmc/mmc.h    |    6 ++
 7 files changed, 199 insertions(+), 42 deletions(-)

diff --git a/drivers/mmc/card/Kconfig b/drivers/mmc/card/Kconfig
index 86948f9..f05e283 100644
--- a/drivers/mmc/card/Kconfig
+++ b/drivers/mmc/card/Kconfig
@@ -14,6 +14,24 @@ config MMC_BLOCK
          mount the filesystem. Almost everyone wishing MMC support
          should say Y or M here.
 
+config MMC_BLOCK_MMC_PART
+       tristate "MMC block MMC device partitioning support"
+       depends on BLOCK
+       default n
+       help
+         Say Y here to enable access to MMC partitions other than
+         the user area, such as the boot partitions. The other partitions
+         will appear as separate mmcblk devices.
+
+config MMC_BLOCK_MMC_PART_BOOT
+       tristate "MMC block MMC boot partition support"
+       depends on MMC_BLOCK_MMC_PART
+       default n
+       help
+         Say Y here to enable access to the MMC boot partitions. Boot
+         partitions are used by some devices to store bootloader information.
+         The boot partitions will appear as separate mmcblk devices.
+
 config MMC_BLOCK_BOUNCE
        bool "Use bounce buffer for simple hosts"
        depends on MMC_BLOCK
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index 7054fd5..ca18218 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -60,9 +60,18 @@ struct mmc_blk_data {
        spinlock_t      lock;
        struct gendisk  *disk;
        struct mmc_queue queue;
+       struct list_head part;
 
        unsigned int    usage;
        unsigned int    read_only;
+       unsigned int    part_type;
+
+       /*
+          Only set in main mmc_blk_data associated
+          with mmc_card with mmc_set_drvdata, and keeps
+          track of the current selected device partition.
+       */
+       unsigned int    part_curr;
 };
 
 static DEFINE_MUTEX(open_lock);
@@ -153,6 +162,28 @@ struct mmc_blk_request {
        struct mmc_data         data;
 };
 
+static inline int mmc_blk_part_switch(struct mmc_card *card,
+                                     struct mmc_blk_data *md)
+{
+       int ret;
+       struct mmc_blk_data *main_md = mmc_get_drvdata(card);
+       if (main_md->part_curr == md->part_type)
+               return 0;
+
+       if (mmc_card_mmc(card)) {
+               card->ext_csd.part_cfg &= ~EXT_CSD_PCFG_ACC_MASK;
+               card->ext_csd.part_cfg |= md->part_type;
+
+               ret = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
+                                EXT_CSD_PCFG, card->ext_csd.part_cfg);
+               if (ret)
+                       return ret;
+       }
+
+       main_md->part_curr = md->part_type;
+       return 0;
+}
+
 static u32 mmc_sd_num_wr_blocks(struct mmc_card *card)
 {
        int err;
@@ -250,8 +281,6 @@ static int mmc_blk_issue_discard_rq(struct mmc_queue *mq, 
struct request *req)
        unsigned int from, nr, arg;
        int err = 0;
 
-       mmc_claim_host(card->host);
-
        if (!mmc_can_erase(card)) {
                err = -EOPNOTSUPP;
                goto out;
@@ -271,8 +300,6 @@ out:
        __blk_end_request(req, err, blk_rq_bytes(req));
        spin_unlock_irq(&md->lock);
 
-       mmc_release_host(card->host);
-
        return err ? 0 : 1;
 }
 
@@ -284,8 +311,6 @@ static int mmc_blk_issue_secdiscard_rq(struct mmc_queue *mq,
        unsigned int from, nr, arg;
        int err = 0;
 
-       mmc_claim_host(card->host);
-
        if (!mmc_can_secure_erase_trim(card)) {
                err = -EOPNOTSUPP;
                goto out;
@@ -307,8 +332,6 @@ out:
        __blk_end_request(req, err, blk_rq_bytes(req));
        spin_unlock_irq(&md->lock);
 
-       mmc_release_host(card->host);
-
        return err ? 0 : 1;
 }
 
@@ -319,8 +342,6 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct 
request *req)
        struct mmc_blk_request brq;
        int ret = 1, disable_multi = 0;
 
-       mmc_claim_host(card->host);
-
        do {
                struct mmc_command cmd;
                u32 readcmd, writecmd, status = 0;
@@ -504,8 +525,6 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct 
request *req)
                spin_unlock_irq(&md->lock);
        } while (ret);
 
-       mmc_release_host(card->host);
-
        return 1;
 
  cmd_err:
@@ -532,8 +551,6 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct 
request *req)
                spin_unlock_irq(&md->lock);
        }
 
-       mmc_release_host(card->host);
-
        spin_lock_irq(&md->lock);
        while (ret)
                ret = __blk_end_request(req, -EIO, blk_rq_cur_bytes(req));
@@ -547,6 +564,7 @@ mmc_blk_set_blksize(struct mmc_blk_data *md, struct 
mmc_card *card);
 
 static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
 {
+       int ret;
 #ifdef CONFIG_MMC_BLOCK_DEFERRED_RESUME
        struct mmc_blk_data *md = mq->data;
        struct mmc_card *card = md->queue.card;
@@ -557,14 +575,25 @@ static int mmc_blk_issue_rq(struct mmc_queue *mq, struct 
request *req)
        }
 #endif
 
+       mmc_claim_host(card->host);
+       ret = mmc_blk_part_switch(card, md);
+       if (ret) {
+               ret = 0;
+               goto out;
+       }
+
        if (req->cmd_flags & REQ_DISCARD) {
                if (req->cmd_flags & REQ_SECURE)
-                       return mmc_blk_issue_secdiscard_rq(mq, req);
+                       ret = mmc_blk_issue_secdiscard_rq(mq, req);
                else
-                       return mmc_blk_issue_discard_rq(mq, req);
+                       ret = mmc_blk_issue_discard_rq(mq, req);
        } else {
-               return mmc_blk_issue_rw_rq(mq, req);
+               ret = mmc_blk_issue_rw_rq(mq, req);
        }
+
+out:
+       mmc_release_host(card->host);
+       return ret;
 }
 
 static inline int mmc_blk_readonly(struct mmc_card *card)
@@ -573,7 +602,8 @@ static inline int mmc_blk_readonly(struct mmc_card *card)
               !(card->csd.cmdclass & CCC_BLOCK_WRITE);
 }
 
-static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
+static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card,
+                                             sector_t size)
 {
        struct mmc_blk_data *md;
        int devidx, ret;
@@ -589,7 +619,6 @@ static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card 
*card)
                goto out;
        }
 
-
        /*
         * Set the read-only status based on the supported commands
         * and the write protect switch.
@@ -603,6 +632,7 @@ static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card 
*card)
        }
 
        spin_lock_init(&md->lock);
+       INIT_LIST_HEAD(&md->part);
        md->usage = 1;
 
        ret = mmc_init_queue(&md->queue, card, &md->lock);
@@ -635,29 +665,84 @@ static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card 
*card)
        sprintf(md->disk->disk_name, "mmcblk%d", devidx);
 
        blk_queue_logical_block_size(md->queue.queue, 512);
+       set_capacity(md->disk, size);
+       return md;
+
+ err_putdisk:
+       put_disk(md->disk);
+ err_kfree:
+       kfree(md);
+ out:
+       return ERR_PTR(ret);
+}
+
+static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
+{
+       sector_t size;
+       struct mmc_blk_data *md;
 
        if (!mmc_card_sd(card) && mmc_card_blockaddr(card)) {
                /*
                 * The EXT_CSD sector count is in number or 512 byte
                 * sectors.
                 */
-               set_capacity(md->disk, card->ext_csd.sectors);
+               size = card->ext_csd.sectors;
        } else {
                /*
                 * The CSD capacity field is in units of read_blkbits.
                 * set_capacity takes units of 512 bytes.
                 */
-               set_capacity(md->disk,
-                       card->csd.capacity << (card->csd.read_blkbits - 9));
+               size = card->csd.capacity << (card->csd.read_blkbits - 9);
        }
+
+       md = mmc_blk_alloc_req(card, size);
+       md->part_type = 0;
        return md;
+}
 
- err_putdisk:
-       put_disk(md->disk);
- err_kfree:
-       kfree(md);
- out:
-       return ERR_PTR(ret);
+static int __maybe_unused mmc_blk_alloc_part(struct mmc_card *card,
+                                            struct mmc_blk_data *md,
+                                            unsigned int part_type,
+                                            sector_t size)
+{
+       char cap_str[10];
+       struct mmc_blk_data *part_md;
+
+       part_md = mmc_blk_alloc_req(card, size);
+       if (IS_ERR(part_md))
+               return PTR_ERR(part_md);
+       part_md->part_type = part_type;
+       list_add(&part_md->part, &md->part);
+
+       string_get_size((u64)get_capacity(part_md->disk) << 9, STRING_UNITS_2,
+                       cap_str, sizeof(cap_str));
+       printk(KERN_INFO "%s: %s %s partition %u %s\n",
+              part_md->disk->disk_name, mmc_card_id(card),
+              mmc_card_name(card), part_md->part_type, cap_str);
+       return 0;
+}
+
+static int mmc_blk_alloc_parts(struct mmc_card *card, struct mmc_blk_data *md)
+{
+       int ret = 0;
+
+       if (!mmc_card_mmc(card))
+               return 0;
+
+#ifdef CONFIG_MMC_BLOCK_MMC_PART_BOOT
+       if (card->ext_csd.boot_size) {
+               ret = mmc_blk_alloc_part(card, md, EXT_CSD_PCFG_ACC_BOOT0,
+                                        card->ext_csd.boot_size >> 9);
+               if (ret)
+                       return ret;
+               ret = mmc_blk_alloc_part(card, md, EXT_CSD_PCFG_ACC_BOOT1,
+                                        card->ext_csd.boot_size >> 9);
+               if (ret)
+                       return ret;
+       }
+#endif
+
+       return ret;
 }
 
 static int
@@ -686,9 +771,37 @@ mmc_blk_set_blksize(struct mmc_blk_data *md, struct 
mmc_card *card)
        return 0;
 }
 
+static void mmc_blk_remove_req(struct mmc_blk_data *md, bool del_disk)
+{
+       if (md) {
+               if (del_disk) {
+
+                       /* Stop new requests from getting into the queue */
+                       del_gendisk(md->disk);
+               }
+
+               /* Then flush out any already in there */
+               mmc_cleanup_queue(&md->queue);
+               mmc_blk_put(md);
+       }
+}
+
+static void mmc_blk_remove_parts(struct mmc_card *card,
+                                struct mmc_blk_data *md, bool del_disk)
+{
+       struct list_head *pos, *q;
+       struct mmc_blk_data *part_md;
+
+       list_for_each_safe(pos, q, &md->part) {
+               part_md = list_entry(pos, struct mmc_blk_data, part);
+               list_del(pos);
+               mmc_blk_remove_req(part_md, del_disk);
+       }
+}
+
 static int mmc_blk_probe(struct mmc_card *card)
 {
-       struct mmc_blk_data *md;
+       struct mmc_blk_data *md, *part_md;
        int err;
 
        char cap_str[10];
@@ -713,17 +826,23 @@ static int mmc_blk_probe(struct mmc_card *card)
                md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
                cap_str, md->read_only ? "(ro)" : "");
 
+       if (mmc_blk_alloc_parts(card, md))
+               goto out;
+
        mmc_set_drvdata(card, md);
 #ifdef CONFIG_MMC_BLOCK_DEFERRED_RESUME
        mmc_set_bus_resume_policy(card->host, 1);
 #endif
        add_disk(md->disk);
+
+       list_for_each_entry(part_md, &md->part, part) {
+               add_disk(part_md->disk);
+       }
        return 0;
 
  out:
-       mmc_cleanup_queue(&md->queue);
-       mmc_blk_put(md);
-
+       mmc_blk_remove_parts(card, md, false);
+       mmc_blk_remove_req(md, false);
        return err;
 }
 
@@ -731,15 +850,8 @@ static void mmc_blk_remove(struct mmc_card *card)
 {
        struct mmc_blk_data *md = mmc_get_drvdata(card);
 
-       if (md) {
-               /* Stop new requests from getting into the queue */
-               del_gendisk(md->disk);
-
-               /* Then flush out any already in there */
-               mmc_cleanup_queue(&md->queue);
-
-               mmc_blk_put(md);
-       }
+       mmc_blk_remove_parts(card, md, true);
+       mmc_blk_remove_req(md, true);
        mmc_set_drvdata(card, NULL);
 #ifdef CONFIG_MMC_BLOCK_DEFERRED_RESUME
        mmc_set_bus_resume_policy(card->host, 0);
@@ -749,23 +861,37 @@ static void mmc_blk_remove(struct mmc_card *card)
 #ifdef CONFIG_PM
 static int mmc_blk_suspend(struct mmc_card *card, pm_message_t state)
 {
+       struct mmc_blk_data *part_md;
        struct mmc_blk_data *md = mmc_get_drvdata(card);
 
        if (md) {
                mmc_queue_suspend(&md->queue);
+               list_for_each_entry(part_md, &md->part, part) {
+                       mmc_queue_suspend(&part_md->queue);
+               }
        }
        return 0;
 }
 
 static int mmc_blk_resume(struct mmc_card *card)
 {
+       struct mmc_blk_data *part_md;
        struct mmc_blk_data *md = mmc_get_drvdata(card);
 
        if (md) {
 #ifndef CONFIG_MMC_BLOCK_DEFERRED_RESUME
                mmc_blk_set_blksize(md, card);
 #endif
+
+               /*
+                 Resume involves the card going into idle state,
+                 so current partition is always the main one.
+                */
+               md->part_curr = md->part_type;
                mmc_queue_resume(&md->queue);
+               list_for_each_entry(part_md, &md->part, part) {
+                       mmc_queue_resume(&part_md->queue);
+               }
        }
        return 0;
 }
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 6909a54..3d757aa 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -284,6 +284,11 @@ static int mmc_read_ext_csd(struct mmc_card *card)
                        ext_csd[EXT_CSD_ERASE_TIMEOUT_MULT];
                card->ext_csd.hc_erase_size =
                        ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE] << 10;
+
+
+               /* There are two boot regions of equal size */
+               card->ext_csd.part_cfg = ext_csd[EXT_CSD_PCFG];
+               card->ext_csd.boot_size = ext_csd[EXT_CSD_BOOT_MULT] * SZ_128K;
        }
 
        if (card->ext_csd.rev >= 4) {
diff --git a/drivers/mmc/core/mmc_ops.h b/drivers/mmc/core/mmc_ops.h
index 653eb8e..b1a806f 100644
--- a/drivers/mmc/core/mmc_ops.h
+++ b/drivers/mmc/core/mmc_ops.h
@@ -20,7 +20,6 @@ int mmc_all_send_cid(struct mmc_host *host, u32 *cid);
 int mmc_set_relative_addr(struct mmc_card *card);
 int mmc_send_csd(struct mmc_card *card, u32 *csd);
 int mmc_send_ext_csd(struct mmc_card *card, u8 *ext_csd);
-int mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value);
 int mmc_send_status(struct mmc_card *card, u32 *status);
 int mmc_send_cid(struct mmc_host *host, u32 *cid);
 int mmc_spi_read_ocr(struct mmc_host *host, int highcap, u32 *ocrp);
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index fe9d7be..0911552 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -45,6 +45,7 @@ struct mmc_ext_csd {
        u8                      rev;
        u8                      erase_group_def;
        u8                      sec_feature_support;
+       u8                      part_cfg;
        unsigned int            sa_timeout;             /* Units: 100ns */
        unsigned int            hs_max_dtr;
        unsigned int            sectors;
@@ -53,6 +54,7 @@ struct mmc_ext_csd {
        unsigned int            sec_trim_mult;  /* Secure trim multiplier  */
        unsigned int            sec_erase_mult; /* Secure erase multiplier */
        unsigned int            trim_timeout;           /* In milliseconds */
+       unsigned int            boot_size;  /* in bytes */
 };
 
 struct sd_scr {
diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h
index 7429033..a6cd7c3 100644
--- a/include/linux/mmc/core.h
+++ b/include/linux/mmc/core.h
@@ -135,6 +135,7 @@ extern void mmc_wait_for_req(struct mmc_host *, struct 
mmc_request *);
 extern int mmc_wait_for_cmd(struct mmc_host *, struct mmc_command *, int);
 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);
 
 #define MMC_ERASE_ARG          0x00000000
 #define MMC_SECURE_ERASE_ARG   0x80000000
diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index dd11ae5..9442cbc 100644
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -252,6 +252,7 @@ struct _mmc_csd {
  */
 
 #define EXT_CSD_ERASE_GROUP_DEF                175     /* R/W */
+#define EXT_CSD_PCFG                   179     /* R/W */
 #define EXT_CSD_ERASED_MEM_CONT                181     /* RO */
 #define EXT_CSD_BUS_WIDTH              183     /* R/W */
 #define EXT_CSD_HS_TIMING              185     /* R/W */
@@ -262,6 +263,7 @@ struct _mmc_csd {
 #define EXT_CSD_S_A_TIMEOUT            217     /* RO */
 #define EXT_CSD_ERASE_TIMEOUT_MULT     223     /* RO */
 #define EXT_CSD_HC_ERASE_GRP_SIZE      224     /* RO */
+#define EXT_CSD_BOOT_MULT              226     /* RO */
 #define EXT_CSD_SEC_TRIM_MULT          229     /* RO */
 #define EXT_CSD_SEC_ERASE_MULT         230     /* RO */
 #define EXT_CSD_SEC_FEATURE_SUPPORT    231     /* RO */
@@ -271,6 +273,10 @@ struct _mmc_csd {
  * EXT_CSD field definitions
  */
 
+#define EXT_CSD_PCFG_ACC_MASK           (0x7)
+#define EXT_CSD_PCFG_ACC_BOOT0          (0x1)
+#define EXT_CSD_PCFG_ACC_BOOT1          (0x2)
+
 #define EXT_CSD_CMD_SET_NORMAL         (1<<0)
 #define EXT_CSD_CMD_SET_SECURE         (1<<1)
 #define EXT_CSD_CMD_SET_CPSECURE       (1<<2)
-- 
1.7.0.4

--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to