[PATCH v3 2/3] mtd: rawnand: cadence: use dma_map_resource for sdma address

[niravkumar.l.rabara@intel.com]

From: Niravkumar L Rabara <niravkumar.l.rabara@intel.com>

Remap the slave DMA I/O resources to enhance driver portability.
Using a physical address causes DMA translation failure when the
ARM SMMU is enabled.

Fixes: ec4ba01e894d ("mtd: rawnand: Add new Cadence NAND driver to MTD subsystem")
Cc: stable@vger.kernel.org
Signed-off-by: Niravkumar L Rabara <niravkumar.l.rabara@intel.com>
---
 .../mtd/nand/raw/cadence-nand-controller.c    | 29 ++++++++++++++++---
 1 file changed, 25 insertions(+), 4 deletions(-)

diff --git a/drivers/mtd/nand/raw/cadence-nand-controller.c b/drivers/mtd/nand/raw/cadence-nand-controller.c
index fb5f671bdb7b..47950a0ac6d2 100644
--- a/drivers/mtd/nand/raw/cadence-nand-controller.c
+++ b/drivers/mtd/nand/raw/cadence-nand-controller.c
@@ -471,6 +471,8 @@ struct cdns_nand_ctrl {
 	struct {
 		void __iomem *virt;
 		dma_addr_t dma;
+		dma_addr_t iova_dma;
+		u32 size;
 	} io;
 
 	int irq;
@@ -1835,11 +1837,11 @@ static int cadence_nand_slave_dma_transfer(struct cdns_nand_ctrl *cdns_ctrl,
 	}
 
 	if (dir == DMA_FROM_DEVICE) {
-		src_dma = cdns_ctrl->io.dma;
+		src_dma = cdns_ctrl->io.iova_dma;
 		dst_dma = buf_dma;
 	} else {
 		src_dma = buf_dma;
-		dst_dma = cdns_ctrl->io.dma;
+		dst_dma = cdns_ctrl->io.iova_dma;
 	}
 
 	tx = dmaengine_prep_dma_memcpy(cdns_ctrl->dmac, dst_dma, src_dma, len,
@@ -2869,6 +2871,7 @@ cadence_nand_irq_cleanup(int irqnum, struct cdns_nand_ctrl *cdns_ctrl)
 static int cadence_nand_init(struct cdns_nand_ctrl *cdns_ctrl)
 {
 	dma_cap_mask_t mask;
+	struct dma_device *dma_dev = cdns_ctrl->dmac->device;
 	int ret;
 
 	cdns_ctrl->cdma_desc = dma_alloc_coherent(cdns_ctrl->dev,
@@ -2912,6 +2915,16 @@ static int cadence_nand_init(struct cdns_nand_ctrl *cdns_ctrl)
 		}
 	}
 
+	cdns_ctrl->io.iova_dma = dma_map_resource(dma_dev->dev, cdns_ctrl->io.dma,
+						  cdns_ctrl->io.size,
+						  DMA_BIDIRECTIONAL, 0);
+
+	ret = dma_mapping_error(dma_dev->dev, cdns_ctrl->io.iova_dma);
+	if (ret) {
+		dev_err(cdns_ctrl->dev, "Failed to map I/O resource to DMA\n");
+		goto dma_release_chnl;
+	}
+
 	nand_controller_init(&cdns_ctrl->controller);
 	INIT_LIST_HEAD(&cdns_ctrl->chips);
 
@@ -2922,18 +2935,22 @@ static int cadence_nand_init(struct cdns_nand_ctrl *cdns_ctrl)
 	if (ret) {
 		dev_err(cdns_ctrl->dev, "Failed to register MTD: %d\n",
 			ret);
-		goto dma_release_chnl;
+		goto unmap_dma_resource;
 	}
 
 	kfree(cdns_ctrl->buf);
 	cdns_ctrl->buf = kzalloc(cdns_ctrl->buf_size, GFP_KERNEL);
 	if (!cdns_ctrl->buf) {
 		ret = -ENOMEM;
-		goto dma_release_chnl;
+		goto unmap_dma_resource;
 	}
 
 	return 0;
 
+unmap_dma_resource:
+	dma_unmap_resource(dma_dev->dev, cdns_ctrl->io.iova_dma,
+			   cdns_ctrl->io.size, DMA_BIDIRECTIONAL, 0);
+
 dma_release_chnl:
 	if (cdns_ctrl->dmac)
 		dma_release_channel(cdns_ctrl->dmac);
@@ -2955,6 +2972,8 @@ static int cadence_nand_init(struct cdns_nand_ctrl *cdns_ctrl)
 static void cadence_nand_remove(struct cdns_nand_ctrl *cdns_ctrl)
 {
 	cadence_nand_chips_cleanup(cdns_ctrl);
+	dma_unmap_resource(cdns_ctrl->dmac->device->dev, cdns_ctrl->io.iova_dma,
+			   cdns_ctrl->io.size, DMA_BIDIRECTIONAL, 0);
 	cadence_nand_irq_cleanup(cdns_ctrl->irq, cdns_ctrl);
 	kfree(cdns_ctrl->buf);
 	dma_free_coherent(cdns_ctrl->dev, sizeof(struct cadence_nand_cdma_desc),
@@ -3019,7 +3038,9 @@ static int cadence_nand_dt_probe(struct platform_device *ofdev)
 	cdns_ctrl->io.virt = devm_platform_get_and_ioremap_resource(ofdev, 1, &res);
 	if (IS_ERR(cdns_ctrl->io.virt))
 		return PTR_ERR(cdns_ctrl->io.virt);
+
 	cdns_ctrl->io.dma = res->start;
+	cdns_ctrl->io.size = resource_size(res);
 
 	dt->clk = devm_clk_get(cdns_ctrl->dev, "nf_clk");
 	if (IS_ERR(dt->clk))
-- 
2.25.1


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