MMC fixes for 3.6-rc5:
 - a firmware bug on several Samsung MoviNAND eMMC models causes
   permanent corruption on the device when secure erase and secure trim
   requests are made, so we disable those requests on these eMMC devices.
 - atmel-mci: fix a hang with some SD cards by waiting for not-busy flag.
 - dw_mmc: low-power mode breaks SDIO interrupts; fix PIO error handling;
   fix handling of error interrupts.
 - mxs-mmc: fix deadlocks; fix compile error due to dma.h arch change.
 - omap: fix broken PIO mode causing memory corruption.
 - sdhci-esdhc: fix card detection.
mmc: omap: fix broken PIO mode

After commit 26b88520b80695a6fa5fd95b5d97c03f4daf87e0 ("mmc:
omap_hsmmc: remove private DMA API implementation"), the Nokia N800
here stopped booting:

[    2.086181] Waiting for root device /dev/mmcblk0p1...
[    2.324066] Unhandled fault: imprecise external abort (0x406) at 0x00000000
[    2.331451] Internal error: : 406 [#1] ARM
[    2.335784] Modules linked in:
[    2.339050] CPU: 0    Not tainted  (3.6.0-rc3 #60)
[    2.344146] PC is at default_idle+0x28/0x30
[    2.348602] LR is at trace_hardirqs_on_caller+0x15c/0x1b0

...

This turned out to be due to memory corruption caused by long-broken
PIO code in drivers/mmc/host/omap.c.  (Previously, this driver had
been using DMA; but the above commit caused the MMC driver to fall
back to PIO mode with an unmodified Kconfig.)

The PIO code, added with the rest of the driver in commit
730c9b7e6630f786fcec026fb11d2e6f2c90fdcb ("[MMC] Add OMAP MMC host
driver"), confused bytes with 16-bit words.  This bug caused memory
located after the PIO transfer buffer to be corrupted with transfers
larger than 32 bytes.  The driver also did not increment the buffer
pointer after the transfer occurred.  This bug resulted in data
corruption during any transfer larger than 64 bytes.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
1 file changed