From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932294AbcKRXYM (ORCPT ); Fri, 18 Nov 2016 18:24:12 -0500 Received: from lelnx193.ext.ti.com ([198.47.27.77]:60380 "EHLO lelnx193.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753676AbcKRXVW (ORCPT ); Fri, 18 Nov 2016 18:21:22 -0500 From: Benoit Parrot To: , Hans Verkuil CC: , Tomi Valkeinen , Jyri Sarha , Peter Ujfalusi , Benoit Parrot Subject: [Patch v2 26/35] media: ti-vpe: vpdma: Use bidirectional cached buffers Date: Fri, 18 Nov 2016 17:20:36 -0600 Message-ID: <20161118232045.24665-27-bparrot@ti.com> X-Mailer: git-send-email 2.9.0 In-Reply-To: <20161118232045.24665-1-bparrot@ti.com> References: <20161118232045.24665-1-bparrot@ti.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Nikhil Devshatwar VPDMA buffer will be used by CPU as well as by the VPDMA. CPU will write/update the VPDMA descriptors containing data about the video buffer DMA addresses. VPDMA will write the "write descriptor" containing the data about the DMA operation. When mapping/unmapping the buffer, driver has to take care of WriteBack and invalidation of the cache so that all the coherency is maintained from both directions. Use DMA_BIDIRECTIONAL to maintain coherency between CPU and VPDMA. Signed-off-by: Nikhil Devshatwar Signed-off-by: Benoit Parrot Acked-by: Hans Verkuil --- drivers/media/platform/ti-vpe/vpdma.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/media/platform/ti-vpe/vpdma.c b/drivers/media/platform/ti-vpe/vpdma.c index 070937fe1af6..2d13644a28a8 100644 --- a/drivers/media/platform/ti-vpe/vpdma.c +++ b/drivers/media/platform/ti-vpe/vpdma.c @@ -367,7 +367,7 @@ int vpdma_map_desc_buf(struct vpdma_data *vpdma, struct vpdma_buf *buf) WARN_ON(buf->mapped); buf->dma_addr = dma_map_single(dev, buf->addr, buf->size, - DMA_TO_DEVICE); + DMA_BIDIRECTIONAL); if (dma_mapping_error(dev, buf->dma_addr)) { dev_err(dev, "failed to map buffer\n"); return -EINVAL; @@ -388,7 +388,8 @@ void vpdma_unmap_desc_buf(struct vpdma_data *vpdma, struct vpdma_buf *buf) struct device *dev = &vpdma->pdev->dev; if (buf->mapped) - dma_unmap_single(dev, buf->dma_addr, buf->size, DMA_TO_DEVICE); + dma_unmap_single(dev, buf->dma_addr, buf->size, + DMA_BIDIRECTIONAL); buf->mapped = false; } -- 2.9.0