usb: dwc2 : invalidate dcache before starting DMA

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>
Acked-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Xu Ziyuan 2016-07-14 14:52:35 +08:00 committed by Simon Glass
parent 4711788267
commit 9424f14183

View File

@ -110,6 +110,9 @@ static int setdma_rx(struct dwc2_ep *ep, struct dwc2_request *req)
ctrl = readl(&reg->out_endp[ep_num].doepctl);
invalidate_dcache_range((unsigned long) ep->dma_buf,
(unsigned long) ep->dma_buf + ep->len);
writel((unsigned int) ep->dma_buf, &reg->out_endp[ep_num].doepdma);
writel(DOEPT_SIZ_PKT_CNT(pktcnt) | DOEPT_SIZ_XFER_SIZE(length),
&reg->out_endp[ep_num].doeptsiz);