Re: [PATCH v2 2/2] PCI: keystone: update to support multiple pci ports

From: Arnd Bergmann
Date: Wed Sep 10 2014 - 04:22:51 EST


On Tuesday 09 September 2014 18:50:13 Murali Karicheri wrote:
> My mistake. It is the device ID, not vendor ID. The PCI driver supports
> PCI h/w on K2HK, K2E and K2L SoCs for which PCI device IDs are assigned as
>
> +#define PCIE_RC_K2HK 0xb008
> +#define PCIE_RC_K2E 0xb009
> +#define PCIE_RC_K2L 0xb00a
> +
>
> and the same driver code runs on all these h/w. The device ID is not
> filled in by default by the h/w, in the config space of the RC at offset
> 1000h "VENDOR_DEVICE_ID Vendor and Device Identification Register".
> Same is available in a seperate SoC register whose offset is specified
> by index 2. This is read by driver and updated in the config space. The
> Vendor ID is however set by default.
>
> There is a mrrs PCI quirk required for Keystone PCI which depends on
> this vendor ID to be filled correctly as it match vendor id/ device id
> of the bridge device to apply the quirk.
>
> Hope this clarify your question.

Ok, I understand now. Yes, this makes sense, though I wonder if it would
have been easier to handle the quirk in a different way based on the
driver rather than the PCI ID. It's probably not worth revisiting though,
unless Bjorn wants to see it done differently now.

Arnd
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