From: Xu Ziyuan Date: Thu, 14 Jul 2016 06:52:35 +0000 (+0800) Subject: usb: dwc2 : invalidate dcache before starting DMA X-Git-Tag: v2016.09-rc2~199 X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=9424f1418377bfb0c95ed36a8854e7fe53436229;p=u-boot 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 Acked-by: Simon Glass --- diff --git a/drivers/usb/gadget/dwc2_udc_otg_xfer_dma.c b/drivers/usb/gadget/dwc2_udc_otg_xfer_dma.c index 12f5c85c31..0d6d2fba8a 100644 --- a/drivers/usb/gadget/dwc2_udc_otg_xfer_dma.c +++ b/drivers/usb/gadget/dwc2_udc_otg_xfer_dma.c @@ -110,6 +110,9 @@ static int setdma_rx(struct dwc2_ep *ep, struct dwc2_request *req) ctrl = readl(®->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, ®->out_endp[ep_num].doepdma); writel(DOEPT_SIZ_PKT_CNT(pktcnt) | DOEPT_SIZ_XFER_SIZE(length), ®->out_endp[ep_num].doeptsiz);