[PATCH v1 3/3] dmaengine: sf-pdma: add mpfs-pdma compatible name

shravan chippa shravan.chippa at microchip.com
Fri Sep 22 02:50:39 PDT 2023


From: Shravan Chippa <shravan.chippa at microchip.com>

Sifive platform dma does not allow out-of-order transfers,
buf out-of-order dma has a significant performance advantage.
Add a PolarFire SoC specific compatible and code to support
for out-of-order dma transfers

Signed-off-by: Shravan Chippa <shravan.chippa at microchip.com>
Reviewed-by: Conor Dooley <conor.dooley at microchip.com>
Signed-off-by: Conor Dooley <conor.dooley at microchip.com>
---
 drivers/dma/sf-pdma/sf-pdma.c | 27 ++++++++++++++++++++++++---
 drivers/dma/sf-pdma/sf-pdma.h |  6 ++++++
 2 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/drivers/dma/sf-pdma/sf-pdma.c b/drivers/dma/sf-pdma/sf-pdma.c
index c7558c9f9ac3..992a804166d5 100644
--- a/drivers/dma/sf-pdma/sf-pdma.c
+++ b/drivers/dma/sf-pdma/sf-pdma.c
@@ -21,6 +21,7 @@
 #include <linux/dma-mapping.h>
 #include <linux/of.h>
 #include <linux/of_dma.h>
+#include <linux/of_device.h>
 #include <linux/slab.h>
 
 #include "sf-pdma.h"
@@ -66,7 +67,7 @@ static struct sf_pdma_desc *sf_pdma_alloc_desc(struct sf_pdma_chan *chan)
 static void sf_pdma_fill_desc(struct sf_pdma_desc *desc,
 			      u64 dst, u64 src, u64 size)
 {
-	desc->xfer_type = PDMA_FULL_SPEED;
+	desc->xfer_type =  desc->chan->pdma->transfer_type;
 	desc->xfer_size = size;
 	desc->dst_addr = dst;
 	desc->src_addr = src;
@@ -520,6 +521,7 @@ static struct dma_chan *sf_pdma_of_xlate(struct of_phandle_args *dma_spec,
 
 static int sf_pdma_probe(struct platform_device *pdev)
 {
+	const struct sf_pdma_driver_platdata *ddata;
 	struct sf_pdma *pdma;
 	int ret, n_chans;
 	const enum dma_slave_buswidth widths =
@@ -545,6 +547,14 @@ static int sf_pdma_probe(struct platform_device *pdev)
 
 	pdma->n_chans = n_chans;
 
+	pdma->transfer_type = PDMA_FULL_SPEED;
+
+	ddata  = of_device_get_match_data(&pdev->dev);
+	if (ddata) {
+		if (ddata->quirks & NO_STRICT_ORDERING)
+			pdma->transfer_type &= ~(NO_STRICT_ORDERING);
+	}
+
 	pdma->membase = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(pdma->membase))
 		return PTR_ERR(pdma->membase);
@@ -629,11 +639,22 @@ static int sf_pdma_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static const struct sf_pdma_driver_platdata mpfs_pdma = {
+	.quirks = NO_STRICT_ORDERING,
+};
+
 static const struct of_device_id sf_pdma_dt_ids[] = {
-	{ .compatible = "sifive,fu540-c000-pdma" },
-	{ .compatible = "sifive,pdma0" },
+	{
+		.compatible = "sifive,fu540-c000-pdma",
+	}, {
+		.compatible = "sifive,pdma0",
+	}, {
+		.compatible = "microchip,mpfs-pdma",
+		.data	    = &mpfs_pdma,
+	},
 	{},
 };
+
 MODULE_DEVICE_TABLE(of, sf_pdma_dt_ids);
 
 static struct platform_driver sf_pdma_driver = {
diff --git a/drivers/dma/sf-pdma/sf-pdma.h b/drivers/dma/sf-pdma/sf-pdma.h
index 5c398a83b491..3b16db4daa0b 100644
--- a/drivers/dma/sf-pdma/sf-pdma.h
+++ b/drivers/dma/sf-pdma/sf-pdma.h
@@ -49,6 +49,7 @@
 
 /* Transfer Type */
 #define PDMA_FULL_SPEED					0xFF000008
+#define NO_STRICT_ORDERING				BIT(3)
 
 /* Error Recovery */
 #define MAX_RETRY					1
@@ -112,8 +113,13 @@ struct sf_pdma {
 	struct dma_device       dma_dev;
 	void __iomem            *membase;
 	void __iomem            *mappedbase;
+	u32			transfer_type;
 	u32			n_chans;
 	struct sf_pdma_chan	chans[];
 };
 
+struct sf_pdma_driver_platdata {
+	u32 quirks;
+};
+
 #endif /* _SF_PDMA_H */
-- 
2.34.1




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