[PATCH v2] PCI: aardvark: Add support for PCI Bridge Subsystem Vendor ID on emulated bridge

[Lorenzo Pieralisi]

On Tue, Jul 12, 2022 at 12:59:15AM +0200, Pali Rohár wrote:
> Register with Subsystem Device/Vendor ID is at offset 0x2c. Export is via
> emulated bridge.

"Export it..." I suppose.

So in short, this patch enables support for the Subsystem Device/Vendor
ID - by reading it in the PCI controller config space and storing it
in the emulated bridge control structures, so that it is exposed in
the respective PCI capability.

Correct ?

Thanks,
Lorenzo

> After this change Subsystem ID is visible in lspci output at line:
> 
>   Capabilities: [40] Subsystem
> 
> Signed-off-by: Pali Rohár <pali at kernel.org>
> 
> ---
> Changes in v2:
> * Fix wrong rebase, do not add PCIE_CORE_EXP_ROM_BAR_REG
> ---
>  drivers/pci/controller/pci-aardvark.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c
> index 74511f015168..060936ef01fe 100644
> --- a/drivers/pci/controller/pci-aardvark.c
> +++ b/drivers/pci/controller/pci-aardvark.c
> @@ -32,6 +32,7 @@
>  #define PCIE_CORE_DEV_ID_REG					0x0
>  #define PCIE_CORE_CMD_STATUS_REG				0x4
>  #define PCIE_CORE_DEV_REV_REG					0x8
> +#define PCIE_CORE_SSDEV_ID_REG					0x2c
>  #define PCIE_CORE_PCIEXP_CAP					0xc0
>  #define PCIE_CORE_ERR_CAPCTL_REG				0x118
>  #define     PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX			BIT(5)
> @@ -982,6 +983,8 @@ static int advk_sw_pci_bridge_init(struct advk_pcie *pcie)
>  	/* Indicates supports for Completion Retry Status */
>  	bridge->pcie_conf.rootcap = cpu_to_le16(PCI_EXP_RTCAP_CRSVIS);
>  
> +	bridge->subsystem_vendor_id = advk_readl(pcie, PCIE_CORE_SSDEV_ID_REG) & 0xffff;
> +	bridge->subsystem_id = advk_readl(pcie, PCIE_CORE_SSDEV_ID_REG) >> 16;
>  	bridge->has_pcie = true;
>  	bridge->data = pcie;
>  	bridge->ops = &advk_pci_bridge_emul_ops;
> -- 
> 2.20.1
>