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

From: Vidya Sagar
Date: Tue Jun 02 2020 - 06:10:28 EST

In this patch series,
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.
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
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.

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(-)