On Mon, Mar 24, 2014 at 9:36 AM, Jaehoon Chung <jh80.chung@xxxxxxxxxxx> wrote: > Hi, > > Did you know that Seungwon has sent the patch "[PATCH 1/7] mmc: dw_mmc: fix the max_blk_count in IDMAC"? > I think this patch looks like same, isn't it? Yes.Its the same one.Please discard this patch. > Plz check it. > > Best Regards, > Jaehoon Chung > > On 03/24/2014 12:53 PM, Yuvaraj Kumar C D wrote: >> From: Alim Akhtar <alim.akhtar@xxxxxxxxxxx> >> >> max_blk_count is currently set incorrectly, and the correct value can >> be determined by looking at the maximum number of bytes which can be >> transferred and the block size. We use the maximum block size to >> determine the minimum number of blocks that the controller should >> support. It could probably do more with a smaller block size but this >> value should be sufficient for good performance. >> >> This improves sequential performance by 82% on write and 6% read on >> one particular device. >> >> TEST= with this patch >> time dd if=/dev/zero of=/usr/local/100 bs=1M count=100 conv=fdatasync >> 100+0 records in >> 100+0 records out >> 104857600 bytes (105 MB) copied, 2.62541 s, 39.9 MB/s >> >> real 0m2.638s >> user 0m0.000s >> sys 0m0.645s >> >> without this patch: >> time dd if=/dev/zero of=/usr/local/100 bs=1M count=100 conv=fdatasync >> 100+0 records in >> 100+0 records out >> 104857600 bytes (105 MB) copied, 3.25873 s, 32.2 MB/s >> >> real 0m3.265s >> user 0m0.005s >> sys 0m0.690s >> >> Signed-off-by: Seungwon Jeon <tgih.jun@xxxxxxxxxxx> >> Signed-off-by: Alim Akhtar <alim.akhtar@xxxxxxxxxxx> >> Signed-off-by: Sonny Rao <sonnyrao@xxxxxxxxxxxx> >> Signed-off-by: Yuvaraj Kumar C D <yuvaraj.cd@xxxxxxxxxxx> >> --- >> drivers/mmc/host/dw_mmc.c | 18 ++++++++++++++++-- >> 1 file changed, 16 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c >> index 0c56faa..2fc4030 100644 >> --- a/drivers/mmc/host/dw_mmc.c >> +++ b/drivers/mmc/host/dw_mmc.c >> @@ -2213,10 +2213,24 @@ static int dw_mci_init_slot(struct dw_mci *host, unsigned int id) >> /* Useful defaults if platform data is unset. */ >> #ifdef CONFIG_MMC_DW_IDMAC >> mmc->max_segs = host->ring_size; >> + >> + /* the BLKSIZ register is 16-bits wide */ >> mmc->max_blk_size = 65536; >> - mmc->max_blk_count = host->ring_size; >> + >> + /* >> + * This value is calculated by taking the size of the >> + * 32-bit BYTCNT (byte count) register and dividing by the >> + * BLKSIZ (block size) register. This is the minimum number >> + * of blocks which could be handled. >> + */ >> + mmc->max_blk_count = 0xFFFF; >> mmc->max_seg_size = 0x1000; >> - mmc->max_req_size = mmc->max_seg_size * mmc->max_blk_count; >> + /* >> + * Maximum request size should be total number of descriptors >> + * times the maximum amount of data each can reference >> + */ >> + >> + mmc->max_req_size = mmc->max_seg_size * mmc->max_segs; >> #else >> mmc->max_segs = 64; >> mmc->max_blk_size = 65536; /* BLKSIZ is 16 bits */ >> > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
