usb: r8a66597-hcd: Flush the D-cache for the pipe-in transfer buffers.
This implements the same D-cache flushing logic for r8a66597-hcd as
Catalin's isp1760 (http://patchwork.kernel.org/patch/76391/) change,
with the same note applying here as well:
When the HDC driver writes the data to the transfer buffers it
pollutes the D-cache (unlike DMA drivers where the device writes
the data). If the corresponding pages get mapped into user space,
there are no additional cache flushing operations performed and
this causes random user space faults on architectures with
separate I and D caches (Harvard) or those with aliasing D-cache.
This fixes up crashes during USB boot on SH7724 and others:
http://marc.info/?l=linux-sh&m=126439837308912&w=2
Reported-by: Goda Yusuke <goda.yusuke@renesas.com>
Tested-by: Goda Yusuke <goda.yusuke@renesas.com>
Cc: stable@kernel.org
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
1 file changed