RE: [PATCH 0/2] PCI: dwc: Add support to handle prefetchable memory separately

From: Gustavo Pimentel
Date: Tue Jun 02 2020 - 13:07:22 EST

On Tue, Jun 2, 2020 at 11:9:38, Vidya Sagar <vidyas@xxxxxxxxxx> wrote:

> In this patch series,
> Patch-1
> adds required infrastructure to deal with prefetchable memory region
> information coming from 'ranges' property of the respective device-tree node
> separately from non-prefetchable memory region information.
> Patch-2
> Adds support to use ATU region-3 for establishing the mapping between CPU
> addresses and PCIe bus addresses.
> It also changes the logic to determine whether mapping is required or not by
> checking both CPU address and PCIe bus address for both prefetchable and
> non-prefetchable regions. If the addresses are same, then, it is understood
> that 1:1 mapping is in place and there is no need to setup ATU mapping
> whereas if the addresses are not the same, then, there is a need to setup ATU
> mapping. This is certainly true for Tegra194 and what I heard from our HW
> engineers is that it should generally be true for any DWC based implementation
> also.
> Hence, I request Synopsys folks (Jingoo Han & Gustavo Pimentel ??) to confirm
> the same so that this particular patch won't cause any regressions for other
> DWC based platforms.

Hi Vidya,

Unfortunately due to the COVID-19 lockdown, I can't access my development
prototype setup to test your patch.
It might take some while until I get the possibility to get access to it


> Vidya Sagar (2):
> PCI: dwc: Add support to handle prefetchable memory separately
> PCI: dwc: Use ATU region to map prefetchable memory region
> .../pci/controller/dwc/pcie-designware-host.c | 46 ++++++++++++++-----
> drivers/pci/controller/dwc/pcie-designware.c | 6 ++-
> drivers/pci/controller/dwc/pcie-designware.h | 8 +++-
> 3 files changed, 45 insertions(+), 15 deletions(-)
> --
> 2.17.1