Re: [PATCH 2/7] PCI: layerscape: Change to use the DWC common link-up check function

From: Rob Herring
Date: Mon Sep 14 2020 - 21:19:50 EST


On Mon, Sep 07, 2020 at 01:37:56PM +0800, Zhiqiang Hou wrote:
> From: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx>
>
> The current Layerscape PCIe driver directly uses the physical layer
> LTSSM code to check the link-up state, which treats the > L0 states
> as link-up. This is not correct, since there is not explicit map
> between link-up state and LTSSM. So this patch changes to use the
> DWC common link-up check function.
>
> Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx>
> ---
> drivers/pci/controller/dwc/pci-layerscape.c | 141 ++------------------
> 1 file changed, 10 insertions(+), 131 deletions(-)

IIRC, the common function uses a debug register. I've been wondering do
the common PCIe config space registers not work on DWC? If you have an
answer, that would be great for some potential additional cleanups.

Either way,

Reviewed-by: Rob Herring <robh@xxxxxxxxxx>