Re: [PATCH 05/12] dmaengine: dw-edma-pcie: Add capability match data

[Frank Li]

On Thu, May 21, 2026 at 03:31:08PM +0900, Koichiro Den wrote:
> Move device-specific capability parsing behind per-device match data.
>
> The existing probe path mixes two decisions: which static template a PCI
> ID uses, and which device-specific capability parser adjusts that
> template. Split those decisions so device-specific discovery can be
> added through match data instead of adding more vendor checks to
> dw_edma_pcie_probe().
>
> No functional change is intended for the existing Synopsys EDDA and
> AMD/Xilinx MDB matches. They still copy the same static template data and
> run the same capability parsing logic before BAR mapping. The MDB entry
> also keeps using endpoint memory physical addresses for descriptor
> windows through a new match-data flag.
>
> Signed-off-by: Koichiro Den <den@xxxxxxxxxxxxx>
> ---
>  drivers/dma/dw-edma/dw-edma-pcie.c | 127 +++++++++++++++++++----------
>  1 file changed, 85 insertions(+), 42 deletions(-)
>
> diff --git a/drivers/dma/dw-edma/dw-edma-pcie.c b/drivers/dma/dw-edma/dw-edma-pcie.c
> index 0b30ce138503..043a7f73bf79 100644
> --- a/drivers/dma/dw-edma/dw-edma-pcie.c
> +++ b/drivers/dma/dw-edma/dw-edma-pcie.c
> @@ -74,6 +74,19 @@ struct dw_edma_pcie_data {
>  	u64				devmem_phys_off;
>  };
>
> +struct dw_edma_pcie_match_data {
> +	const struct dw_edma_pcie_data *data;
> +	/*
> +	 * Mandatory callback. It may leave @pdata unchanged when the static
> +	 * template already describes the device.
> +	 */
> +	int (*parse_caps)(struct pci_dev *pdev,
> +			  struct dw_edma_pcie_data *pdata, bool *non_ll);

Needn't non_ll here. This information should be already save into
dw_edma_chip::cfg_no_ll

> +	unsigned long flags;
> +};
...
>
> +static const struct dw_edma_pcie_match_data snps_edda_match_data = {
> +	.data = &snps_edda_data,
> +	.parse_caps = dw_edma_pcie_parse_synopsys_caps,
> +};
> +
> +static const struct dw_edma_pcie_match_data xilinx_mdb_match_data = {
> +	.data = &xilinx_mdb_data,
> +	.parse_caps = dw_edma_pcie_parse_xilinx_caps,
> +	.flags = DW_EDMA_PCIE_F_DEVMEM_PHYS_OFF,
> +};
> +
>  static const struct pci_device_id dw_edma_pcie_id_table[] = {
> -	{ PCI_DEVICE_DATA(SYNOPSYS, EDDA, &snps_edda_data) },
> +	{ PCI_DEVICE_DATA(SYNOPSYS, EDDA, &snps_edda_match_data) },
>  	{ PCI_VDEVICE(XILINX, PCI_DEVICE_ID_XILINX_B054),
> -	  (kernel_ulong_t)&xilinx_mdb_data },
> +	  (kernel_ulong_t)&xilinx_mdb_match_data },

On going thread
https://lore.kernel.org/linux-i3c/afmEo54iWgk54M3Y@monoceros/

.driver_data = (kernel_ulong_t)&xilinx_mdb_data;

>  	{ }
>  };
>  MODULE_DEVICE_TABLE(pci, dw_edma_pcie_id_table);
> --
> 2.51.0
>