Re: [U-Boot] [PATCH v4 4/4] usb: dwc2 : invalidate dcache before starting DMA

15 Jul 2016

      On 14 July 2016 at 00:52, Ziyuan Xu xzy.xu@rock-chips.com wrote:
...
From: Xu Ziyuan xzy.xu@rock-chips.com
Invalidate dcache before starting the DMA to ensure coherency. In case
there are any dirty lines from the DMA buffer in the cache, subsequent
cache-line replacements may corrupt the buffer in memory while the DMA
is still going on. Cache-line replacement can happen if the CPU tries to
bring some other memory locations into the cache while the DMA is going
on.
Signed-off-by: Ziyuan Xu xzy.xu@rock-chips.com

Changes in v4: None
Changes in v3:

New commit since v3 to fix the coherence issue between memory and

cache
Changes in v2: None
drivers/usb/gadget/dwc2_udc_otg_xfer_dma.c | 3 +++
 1 file changed, 3 insertions(+)
Acked-by: Simon Glass sjg@chromium.org