Re: [PATCH 09/12] dmaengine: dw-edma-pcie: Add register offset match flag

[Frank Li]

On Thu, May 21, 2026 at 03:31:12PM +0900, Koichiro Den wrote:
> Add a match-data flag for devices whose DMA register block starts at an
> offset inside the mapped BAR. Existing Synopsys EDDA and AMD/Xilinx MDB
> matches keep using the BAR mapping base directly.
>
> No functional change intended.
>
> Signed-off-by: Koichiro Den <den@xxxxxxxxxxxxx>
> ---
>  drivers/dma/dw-edma/dw-edma-pcie.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/dma/dw-edma/dw-edma-pcie.c b/drivers/dma/dw-edma/dw-edma-pcie.c
> index 651269708cc5..6b375a58c550 100644
> --- a/drivers/dma/dw-edma/dw-edma-pcie.c
> +++ b/drivers/dma/dw-edma/dw-edma-pcie.c
> @@ -88,6 +88,7 @@ struct dw_edma_pcie_match_data {
>
>  #define DW_EDMA_PCIE_F_DEVMEM_PHYS_OFF	BIT(0)
>  #define DW_EDMA_PCIE_F_RAW_SLAVE_ADDR	BIT(1)
> +#define DW_EDMA_PCIE_F_REG_OFFSET	BIT(2)
>
>  static const struct dw_edma_pcie_data snps_edda_data = {
>  	/* eDMA registers location */
> @@ -450,6 +451,8 @@ static int dw_edma_pcie_probe(struct pci_dev *pdev,
>  	chip->reg_base = pcim_iomap_table(pdev)[dma_data->rg.bar];
>  	if (!chip->reg_base)
>  		return -ENOMEM;
> +	if (match->flags & DW_EDMA_PCIE_F_REG_OFFSET)
> +		chip->reg_base += dma_data->rg.off;

suppose default rg.off is 0, so needn't flag DW_EDMA_PCIE_F_REG_OFFSET.

Frank

>
>  	for (i = 0; i < chip->ll_wr_cnt && !non_ll; i++) {
>  		struct dw_edma_region *ll_region = &chip->ll_region_wr[i];
> --
> 2.51.0
>