[PATCH v1 2/6] dmaengine: dw-edma: Introduce helpers for getting the eDMA/HDMA max channel count

From: Mrinmay Sarkar
Date: Fri Jan 19 2024 - 08:01:06 EST


From: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>

Add common helpers for getting the eDMA/HDMA max channel count.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Signed-off-by: Mrinmay Sarkar <quic_msarkar@xxxxxxxxxxx>
---
drivers/dma/dw-edma/dw-edma-core.c | 18 ++++++++++++++++++
drivers/pci/controller/dwc/pcie-designware.c | 6 +++---
include/linux/dma/edma.h | 14 ++++++++++++++
3 files changed, 35 insertions(+), 3 deletions(-)

diff --git a/drivers/dma/dw-edma/dw-edma-core.c b/drivers/dma/dw-edma/dw-edma-core.c
index 7fe1c19..2bd6e43 100644
--- a/drivers/dma/dw-edma/dw-edma-core.c
+++ b/drivers/dma/dw-edma/dw-edma-core.c
@@ -902,6 +902,24 @@ static int dw_edma_irq_request(struct dw_edma *dw,
return err;
}

+static u32 dw_edma_get_max_ch(enum dw_edma_map_format mf, enum dw_edma_dir dir)
+{
+ if (mf == EDMA_MF_HDMA_NATIVE)
+ return HDMA_MAX_NR_CH;
+
+ return dir == EDMA_DIR_WRITE ? EDMA_MAX_WR_CH : EDMA_MAX_RD_CH;
+}
+
+u32 dw_edma_get_max_rd_ch(enum dw_edma_map_format mf)
+{
+ return dw_edma_get_max_ch(mf, EDMA_DIR_READ);
+}
+
+u32 dw_edma_get_max_wr_ch(enum dw_edma_map_format mf)
+{
+ return dw_edma_get_max_ch(mf, EDMA_DIR_WRITE);
+}
+
int dw_edma_probe(struct dw_edma_chip *chip)
{
struct device *dev;
diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index eca047a..96575b8 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -864,7 +864,7 @@ static int dw_pcie_edma_irq_vector(struct dw_edma_chip *edma, unsigned int nr)
char name[6];
int ret;

- if (nr >= EDMA_MAX_WR_CH + EDMA_MAX_RD_CH)
+ if (nr >= dw_edma_get_max_rd_ch(edma->mf) + dw_edma_get_max_wr_ch(edma->mf))
return -EINVAL;

ret = platform_get_irq_byname_optional(pdev, "dma");
@@ -923,8 +923,8 @@ static int dw_pcie_edma_find_chip(struct dw_pcie *pci)
pci->edma.ll_rd_cnt = FIELD_GET(PCIE_DMA_NUM_RD_CHAN, val);

/* Sanity check the channels count if the mapping was incorrect */
- if (!pci->edma.ll_wr_cnt || pci->edma.ll_wr_cnt > EDMA_MAX_WR_CH ||
- !pci->edma.ll_rd_cnt || pci->edma.ll_rd_cnt > EDMA_MAX_RD_CH)
+ if (!pci->edma.ll_wr_cnt || pci->edma.ll_wr_cnt > dw_edma_get_max_wr_ch(pci->edma.mf) ||
+ !pci->edma.ll_rd_cnt || pci->edma.ll_rd_cnt > dw_edma_get_max_rd_ch(pci->edma.mf))
return -EINVAL;

return 0;
diff --git a/include/linux/dma/edma.h b/include/linux/dma/edma.h
index 7197a58..550f6a4 100644
--- a/include/linux/dma/edma.h
+++ b/include/linux/dma/edma.h
@@ -106,6 +106,9 @@ struct dw_edma_chip {
#if IS_REACHABLE(CONFIG_DW_EDMA)
int dw_edma_probe(struct dw_edma_chip *chip);
int dw_edma_remove(struct dw_edma_chip *chip);
+
+u32 dw_edma_get_max_rd_ch(enum dw_edma_map_format mf);
+u32 dw_edma_get_max_wr_ch(enum dw_edma_map_format mf);
#else
static inline int dw_edma_probe(struct dw_edma_chip *chip)
{
@@ -116,6 +119,17 @@ static inline int dw_edma_remove(struct dw_edma_chip *chip)
{
return 0;
}
+
+static inline u32 dw_edma_get_max_rd_ch(enum dw_edma_map_format mf)
+{
+ return 0;
+}
+
+static inline u32 dw_edma_get_max_wr_ch(enum dw_edma_map_format mf)
+{
+ return 0;
+}
+
#endif /* CONFIG_DW_EDMA */

#endif /* _DW_EDMA_H */
--
2.7.4