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

shravan chippa
2023-09-22T09:50:33Z

From: Shravan Chippa <shravan.chippa@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@microchip.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@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