diff mbox

[v2,1/7] mmc: dw_mmc: fix the max_blk_count in IDMAC

Message ID 000101cf48e6$da954f90$8fbfeeb0$%jun@samsung.com (mailing list archive)
State New, archived
Headers show

Commit Message

Seungwon Jeon March 26, 2014, 11:30 a.m. UTC
Even though 1MB is reserved for descriptor table in IDMAC,
the dw_mmc host driver is allowed to receive only maximum
128KB block length in one request. This is caused by setting
improper max_blk_count. It needs to be e adjusted so that
descriptor table is used fully. It is found that the performance
is improved with the increased the max_blk_count.

Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
---
 drivers/mmc/host/dw_mmc.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

Comments

Jaehoon Chung April 14, 2014, 7:30 a.m. UTC | #1
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>

On 03/26/2014 08:30 PM, Seungwon Jeon wrote:
> Even though 1MB is reserved for descriptor table in IDMAC,
> the dw_mmc host driver is allowed to receive only maximum
> 128KB block length in one request. This is caused by setting
> improper max_blk_count. It needs to be e adjusted so that
> descriptor table is used fully. It is found that the performance
> is improved with the increased the max_blk_count.
> 
> Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
> ---
>  drivers/mmc/host/dw_mmc.c |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
> index 3a6721e..aeb38f9 100644
> --- a/drivers/mmc/host/dw_mmc.c
> +++ b/drivers/mmc/host/dw_mmc.c
> @@ -2101,9 +2101,9 @@ static int dw_mci_init_slot(struct dw_mci *host, unsigned int id)
>  #ifdef CONFIG_MMC_DW_IDMAC
>  		mmc->max_segs = host->ring_size;
>  		mmc->max_blk_size = 65536;
> -		mmc->max_blk_count = host->ring_size;
>  		mmc->max_seg_size = 0x1000;
> -		mmc->max_req_size = mmc->max_seg_size * mmc->max_blk_count;
> +		mmc->max_req_size = mmc->max_seg_size * host->ring_size;
> +		mmc->max_blk_count = mmc->max_req_size / 512;
>  #else
>  		mmc->max_segs = 64;
>  		mmc->max_blk_size = 65536; /* BLKSIZ is 16 bits */
> 

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diff mbox

Patch

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 3a6721e..aeb38f9 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -2101,9 +2101,9 @@  static int dw_mci_init_slot(struct dw_mci *host, unsigned int id)
 #ifdef CONFIG_MMC_DW_IDMAC
 		mmc->max_segs = host->ring_size;
 		mmc->max_blk_size = 65536;
-		mmc->max_blk_count = host->ring_size;
 		mmc->max_seg_size = 0x1000;
-		mmc->max_req_size = mmc->max_seg_size * mmc->max_blk_count;
+		mmc->max_req_size = mmc->max_seg_size * host->ring_size;
+		mmc->max_blk_count = mmc->max_req_size / 512;
 #else
 		mmc->max_segs = 64;
 		mmc->max_blk_size = 65536; /* BLKSIZ is 16 bits */