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a6327b5e57
When running OMAP1 kernel on QEMU, MMC access is annoyingly noisy:
MMC: CTO of 0xff and 0xfe cannot be used!
MMC: CTO of 0xff and 0xfe cannot be used!
MMC: CTO of 0xff and 0xfe cannot be used!
[ad inf.]
Emulator warnings appear to be valid. The TI document SPRU680 [1]
("OMAP5910 Dual-Core Processor MultiMedia Card/Secure Data Memory Card
(MMC/SD) Reference Guide") page 36 states that the maximum timeout is 253
cycles and "0xff and 0xfe cannot be used".
Fix by using 0xfd as the maximum timeout.
Tested using QEMU 2.5 (Siemens SX1 machine, OMAP310), and also checked on
real hardware using Palm TE (OMAP310), Nokia 770 (OMAP1710) and Nokia N810
(OMAP2420) that MMC works as before.
[1] http://www.ti.com/lit/ug/spru680/spru680.pdf
Fixes: 730c9b7e66 ("[MMC] Add OMAP MMC host driver")
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
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.