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0b47979068
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: Russell King <rmk+kernel@armlinux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.