Skip to content
Commit 4d7a081d authored by Russell King's avatar Russell King Committed by Greg Kroah-Hartman
Browse files

mmc: omap_hsmmc: fix DMA API warning



commit 0b479790 upstream.

While booting with rootfs on MMC, the following warning is encountered
on OMAP4430:

omap-dma-engine 4a056000.dma-controller: DMA-API: mapping sg segment longer than device claims to support [len=69632] [max=65536]

This is because the DMA engine has a default maximum segment size of 64K
but HSMMC sets:

        mmc->max_blk_size = 512;       /* Block Length at max can be 1024 */
        mmc->max_blk_count = 0xFFFF;    /* No. of Blocks is 16 bits */
        mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
        mmc->max_seg_size = mmc->max_req_size;

which ends up telling the block layer that we support a maximum segment
size of 65535*512, which exceeds the advertised DMA engine capabilities.

Fix this by clamping the maximum segment size to the lower of the
maximum request size and of the DMA engine device used for either DMA
channel.

Signed-off-by: default avatarRussell King <rmk+kernel@armlinux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent b097c443
Loading
Loading
Loading
Loading
0% Loading or .
You are about to add 0 people to the discussion. Proceed with caution.
Please register or to comment