linux/drivers/mmc/card/queue.h
Seungwon Jeon ce39f9d17c mmc: support packed write command for eMMC4.5 devices
This patch supports packed write command of eMMC4.5 devices.  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. Large amounts of
data in one transfer rather than several data of small size are
effective for eMMC write internally.  As a result, packed command help
write throughput be improved.  The following tables show the results
of packed write.

Type A:
test     none |  packed
iozone   25.8 |  31
tiotest  27.6 |  31.2
lmdd     31.2 |  35.4

Type B:
test     none |  packed
iozone   44.1 |  51.1
tiotest  47.9 |  52.5
lmdd     51.6 |  59.2

Type C:
test     none |  packed
iozone   19.5 |  32
tiotest  19.9 |  34.5
lmdd     22.8 |  40.7

Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Reviewed-by: Maya Erez <merez@codeaurora.org>
Reviewed-by: Namjae Jeon <linkinjeon@gmail.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
2013-02-24 14:37:16 -05:00

75 lines
1.8 KiB
C

#ifndef MMC_QUEUE_H
#define MMC_QUEUE_H
struct request;
struct task_struct;
struct mmc_blk_request {
struct mmc_request mrq;
struct mmc_command sbc;
struct mmc_command cmd;
struct mmc_command stop;
struct mmc_data data;
};
enum mmc_packed_type {
MMC_PACKED_NONE = 0,
MMC_PACKED_WRITE,
};
#define mmc_packed_cmd(type) ((type) != MMC_PACKED_NONE)
#define mmc_packed_wr(type) ((type) == MMC_PACKED_WRITE)
struct mmc_packed {
struct list_head list;
u32 cmd_hdr[1024];
unsigned int blocks;
u8 nr_entries;
u8 retries;
s16 idx_failure;
};
struct mmc_queue_req {
struct request *req;
struct mmc_blk_request brq;
struct scatterlist *sg;
char *bounce_buf;
struct scatterlist *bounce_sg;
unsigned int bounce_sg_len;
struct mmc_async_req mmc_active;
enum mmc_packed_type cmd_type;
struct mmc_packed *packed;
};
struct mmc_queue {
struct mmc_card *card;
struct task_struct *thread;
struct semaphore thread_sem;
unsigned int flags;
#define MMC_QUEUE_SUSPENDED (1 << 0)
#define MMC_QUEUE_NEW_REQUEST (1 << 1)
int (*issue_fn)(struct mmc_queue *, struct request *);
void *data;
struct request_queue *queue;
struct mmc_queue_req mqrq[2];
struct mmc_queue_req *mqrq_cur;
struct mmc_queue_req *mqrq_prev;
};
extern int mmc_init_queue(struct mmc_queue *, struct mmc_card *, spinlock_t *,
const char *);
extern void mmc_cleanup_queue(struct mmc_queue *);
extern void mmc_queue_suspend(struct mmc_queue *);
extern void mmc_queue_resume(struct mmc_queue *);
extern unsigned int mmc_queue_map_sg(struct mmc_queue *,
struct mmc_queue_req *);
extern void mmc_queue_bounce_pre(struct mmc_queue_req *);
extern void mmc_queue_bounce_post(struct mmc_queue_req *);
extern int mmc_packed_init(struct mmc_queue *, struct mmc_card *);
extern void mmc_packed_clean(struct mmc_queue *);
#endif