[PATCH v3 4/4] arm64: dts: rockchip: Update PCI host bridge window to 32-bit address memory

Punit Agrawal
2021-06-07T11:34:39Z

The PCIe host bridge on RK3399 advertises a single 64-bit memory
address range even though it lies entirely below 4GB.

Previously the OF PCI range parser treated 64-bit ranges more
leniently (i.e., as 32-bit), but since commit 9d57e61bf723 ("of/pci:
Add IORESOURCE_MEM_64 to resource flags for 64-bit memory addresses")
the code takes a stricter view and treats the ranges as advertised in
the device tree (i.e, as 64-bit).

The change in behaviour causes failure when allocating bus addresses
to devices connected behind a PCI-to-PCI bridge that require
non-prefetchable memory ranges. The allocation failure was observed
for certain Samsung NVMe drives connected to RockPro64 boards.

Update the host bridge window attributes to treat it as 32-bit address
memory. This fixes the allocation failure observed since commit
9d57e61bf723.

Reported-by: Alexandru Elisei <alexandru.elisei@arm.com>
Link: https://lore.kernel.org/r/7a1e2ebc-f7d8-8431-d844-41a9c36a8911@arm.com
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Punit Agrawal <punitagrawal@gmail.com>
Tested-by: Alexandru Elisei <alexandru.elisei@arm.com>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Rob Herring <robh+dt@kernel.org>
---
arch/arm64/boot/dts/rockchip/rk3399.dtsi | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/rockchip/rk3399.dtsi b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
index 634a91af8e83..4b854eb21f72 100644
--- a/arch/arm64/boot/dts/rockchip/rk3399.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
@@ -227,7 +227,7 @@ pcie0: pcie@f8000000 {
<&pcie_phy 2>, <&pcie_phy 3>;
phy-names = "pcie-phy-0", "pcie-phy-1",
"pcie-phy-2", "pcie-phy-3";
- ranges = <0x83000000 0x0 0xfa000000 0x0 0xfa000000 0x0 0x1e00000>,
+ ranges = <0x82000000 0x0 0xfa000000 0x0 0xfa000000 0x0 0x1e00000>,
<0x81000000 0x0 0xfbe00000 0x0 0xfbe00000 0x0 0x100000>;
resets = <&cru SRST_PCIE_CORE>, <&cru SRST_PCIE_MGMT>,
<&cru SRST_PCIE_MGMT_STICKY>, <&cru SRST_PCIE_PIPE>,
--
2.30.2