From patchwork Wed Jun 1 15:22:29 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Niklas_S=C3=B6derlund?= X-Patchwork-Id: 9147607 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id BFCD060467 for ; Wed, 1 Jun 2016 15:25:54 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B1E9026C4D for ; Wed, 1 Jun 2016 15:25:54 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A626A26CB8; Wed, 1 Jun 2016 15:25:54 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 47EBD26C4D for ; Wed, 1 Jun 2016 15:25:54 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1b880W-0000Um-VW; Wed, 01 Jun 2016 15:24:32 +0000 Received: from smtp-4.sys.kth.se ([2001:6b0:1:1300:250:56ff:fea6:2de3]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1b87zx-0008Nf-7S for linux-arm-kernel@lists.infradead.org; Wed, 01 Jun 2016 15:24:00 +0000 Received: from smtp-4.sys.kth.se (localhost.localdomain [127.0.0.1]) by smtp-4.sys.kth.se (Postfix) with ESMTP id 16264ECC; Wed, 1 Jun 2016 17:23:16 +0200 (CEST) X-Virus-Scanned: by amavisd-new at kth.se Received: from smtp-4.sys.kth.se ([127.0.0.1]) by smtp-4.sys.kth.se (smtp-4.sys.kth.se [127.0.0.1]) (amavisd-new, port 10024) with LMTP id dssBsSacouWG; Wed, 1 Jun 2016 17:23:15 +0200 (CEST) X-KTH-Auth: niso [89.233.230.99] X-KTH-mail-from: niklas.soderlund+renesas@ragnatech.se Received: from bismarck.berto.se (dynamic.0.6.79d1f80.14cc20ac3a53.cust.bredband2.com [89.233.230.99]) by smtp-4.sys.kth.se (Postfix) with ESMTPSA id A7AC2488; Wed, 1 Jun 2016 17:23:14 +0200 (CEST) From: =?UTF-8?q?Niklas=20S=C3=B6derlund?= To: hch@infradead.org, linux-renesas-soc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, dmaengine@vger.kernel.org, iommu@lists.linux-foundation.org Subject: [PATCHv7 6/6] dmaengine: rcar-dmac: add iommu support for slave transfers Date: Wed, 1 Jun 2016 17:22:29 +0200 Message-Id: <1464794549-6601-7-git-send-email-niklas.soderlund+renesas@ragnatech.se> X-Mailer: git-send-email 2.8.2 In-Reply-To: <1464794549-6601-1-git-send-email-niklas.soderlund+renesas@ragnatech.se> References: <1464794549-6601-1-git-send-email-niklas.soderlund+renesas@ragnatech.se> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160601_082357_770115_D40368F8 X-CRM114-Status: GOOD ( 14.49 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: =?UTF-8?q?Niklas=20S=C3=B6derlund?= , arnd@arndb.de, vinod.koul@intel.com, linus.walleij@linaro.org, laurent.pinchart@ideasonboard.com, dan.j.williams@intel.com, robin.murphy@arm.com Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Enable slave transfers to a device behind a IPMMU by mapping the slave addresses using the dma-mapping API. Signed-off-by: Niklas Söderlund --- drivers/dma/sh/rcar-dmac.c | 82 +++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 74 insertions(+), 8 deletions(-) diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c index b0c3bb2..8592598 100644 --- a/drivers/dma/sh/rcar-dmac.c +++ b/drivers/dma/sh/rcar-dmac.c @@ -128,6 +128,18 @@ struct rcar_dmac_chan_slave { }; /* + * struct rcar_dmac_chan_map - Map of slave device phys to dma address + * @addr: slave dma address + * @dir: direction of mapping + * @slave: slave configuration that is mapped + */ +struct rcar_dmac_chan_map { + dma_addr_t addr; + enum dma_data_direction dir; + struct rcar_dmac_chan_slave slave; +}; + +/* * struct rcar_dmac_chan - R-Car Gen2 DMA Controller Channel * @chan: base DMA channel object * @iomem: channel I/O memory base @@ -152,6 +164,7 @@ struct rcar_dmac_chan { struct rcar_dmac_chan_slave src; struct rcar_dmac_chan_slave dst; + struct rcar_dmac_chan_map map; int mid_rid; spinlock_t lock; @@ -1027,13 +1040,65 @@ rcar_dmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dma_dest, DMA_MEM_TO_MEM, flags, false); } +static int rcar_dmac_map_slave_addr(struct dma_chan *chan, + enum dma_transfer_direction dir) +{ + struct rcar_dmac_chan *rchan = to_rcar_dmac_chan(chan); + struct rcar_dmac_chan_map *map = &rchan->map; + phys_addr_t dev_addr; + size_t dev_size; + enum dma_data_direction dev_dir; + + if (dir == DMA_DEV_TO_MEM) { + dev_addr = rchan->src.slave_addr; + dev_size = rchan->src.xfer_size; + dev_dir = DMA_TO_DEVICE; + } else { + dev_addr = rchan->dst.slave_addr; + dev_size = rchan->dst.xfer_size; + dev_dir = DMA_FROM_DEVICE; + } + + /* Reuse current map if possible. */ + if (dev_addr == map->slave.slave_addr && + dev_size == map->slave.xfer_size && + dev_dir == map->dir) + return 0; + + /* Remove old mapping if present. */ + if (map->slave.xfer_size) + dma_unmap_resource(chan->device->dev, map->addr, + map->slave.xfer_size, map->dir, NULL); + map->slave.xfer_size = 0; + + /* Create new slave address map. */ + map->addr = dma_map_resource(chan->device->dev, dev_addr, dev_size, + dev_dir, NULL); + + if (dma_mapping_error(chan->device->dev, map->addr)) { + dev_err(chan->device->dev, + "chan%u: failed to map %zx@%pap", rchan->index, + dev_size, &dev_addr); + return -EIO; + } + + dev_dbg(chan->device->dev, "chan%u: map %zx@%pap to %pad dir: %s\n", + rchan->index, dev_size, &dev_addr, &map->addr, + dev_dir == DMA_TO_DEVICE ? "DMA_TO_DEVICE" : "DMA_FROM_DEVICE"); + + map->slave.slave_addr = dev_addr; + map->slave.xfer_size = dev_size; + map->dir = dev_dir; + + return 0; +} + static struct dma_async_tx_descriptor * rcar_dmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len, enum dma_transfer_direction dir, unsigned long flags, void *context) { struct rcar_dmac_chan *rchan = to_rcar_dmac_chan(chan); - dma_addr_t dev_addr; /* Someone calling slave DMA on a generic channel? */ if (rchan->mid_rid < 0 || !sg_len) { @@ -1043,9 +1108,10 @@ rcar_dmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, return NULL; } - dev_addr = dir == DMA_DEV_TO_MEM - ? rchan->src.slave_addr : rchan->dst.slave_addr; - return rcar_dmac_chan_prep_sg(rchan, sgl, sg_len, dev_addr, + if (rcar_dmac_map_slave_addr(chan, dir)) + return NULL; + + return rcar_dmac_chan_prep_sg(rchan, sgl, sg_len, rchan->map.addr, dir, flags, false); } @@ -1059,7 +1125,6 @@ rcar_dmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, struct rcar_dmac_chan *rchan = to_rcar_dmac_chan(chan); struct dma_async_tx_descriptor *desc; struct scatterlist *sgl; - dma_addr_t dev_addr; unsigned int sg_len; unsigned int i; @@ -1071,6 +1136,9 @@ rcar_dmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, return NULL; } + if (rcar_dmac_map_slave_addr(chan, dir)) + return NULL; + sg_len = buf_len / period_len; if (sg_len > RCAR_DMAC_MAX_SG_LEN) { dev_err(chan->device->dev, @@ -1098,9 +1166,7 @@ rcar_dmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, sg_dma_len(&sgl[i]) = period_len; } - dev_addr = dir == DMA_DEV_TO_MEM - ? rchan->src.slave_addr : rchan->dst.slave_addr; - desc = rcar_dmac_chan_prep_sg(rchan, sgl, sg_len, dev_addr, + desc = rcar_dmac_chan_prep_sg(rchan, sgl, sg_len, rchan->map.addr, dir, flags, true); kfree(sgl);