Re: [PATCH 7/9] PCI: endpoint: pci-epf-test: Advertise reserved BARs

[Frank Li <Frank.li@nxp.com>]

On Tue, Feb 17, 2026 at 10:27:13PM +0100, Niklas Cassel wrote:
> Advertise reserved BARs as reserved in the Capabilities register,
> such that the host side driver will be able to skip reserved BARs.
>
> Signed-off-by: Niklas Cassel <cassel@kernel.org>
> ---
>  drivers/pci/endpoint/functions/pci-epf-test.c | 24 +++++++++++++++++++
>  1 file changed, 24 insertions(+)
>
> diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
> index 0cb7af0919dc..4c7e42fe5d8e 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-test.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-test.c
> @@ -64,6 +64,12 @@
>  #define CAP_MSIX			BIT(2)
>  #define CAP_INTX			BIT(3)
>  #define CAP_SUBRANGE_MAPPING		BIT(4)
> +#define CAP_BAR0_RESERVED		BIT(5)
> +#define CAP_BAR1_RESERVED		BIT(6)
> +#define CAP_BAR2_RESERVED		BIT(7)
> +#define CAP_BAR3_RESERVED		BIT(8)
> +#define CAP_BAR4_RESERVED		BIT(9)
> +#define CAP_BAR5_RESERVED		BIT(10)
>
>  #define PCI_EPF_TEST_BAR_SUBRANGE_NSUB	2
>
> @@ -1106,6 +1112,24 @@ static void pci_epf_test_set_capabilities(struct pci_epf *epf)
>  	    epf_test->epc_features->subrange_mapping)
>  		caps |= CAP_SUBRANGE_MAPPING;
>
> +	if (epf_test->epc_features->bar[BAR_0].type == BAR_RESERVED)
> +		caps |= CAP_BAR0_RESERVED;

Is it BAR_DISABLE? suppose BAR_RESERVED redefine as hardware MMIO mapped
bar

Frank

> +
> +	if (epf_test->epc_features->bar[BAR_1].type == BAR_RESERVED)
> +		caps |= CAP_BAR1_RESERVED;
> +
> +	if (epf_test->epc_features->bar[BAR_2].type == BAR_RESERVED)
> +		caps |= CAP_BAR2_RESERVED;
> +
> +	if (epf_test->epc_features->bar[BAR_3].type == BAR_RESERVED)
> +		caps |= CAP_BAR3_RESERVED;
> +
> +	if (epf_test->epc_features->bar[BAR_4].type == BAR_RESERVED)
> +		caps |= CAP_BAR4_RESERVED;
> +
> +	if (epf_test->epc_features->bar[BAR_5].type == BAR_RESERVED)
> +		caps |= CAP_BAR5_RESERVED;
> +
>  	reg->caps = cpu_to_le32(caps);
>  }
>
> --
> 2.53.0
>