Re: [PATCH v3 4/4] arm64: dts: rockchip: Update PCI host bridge window to 32-bit address memory
From: Punit Agrawal
Date: Wed Jun 16 2021 - 09:00:32 EST
Heiko Stübner <heiko@xxxxxxxxx> writes:
> Am Dienstag, 15. Juni 2021, 23:29:12 CEST schrieb Rob Herring:
>> On Thu, Jun 10, 2021 at 3:50 PM Heiko Stübner <heiko@xxxxxxxxx> wrote:
>> > Hi,
>> > Am Montag, 7. Juni 2021, 13:28:56 CEST schrieb Punit Agrawal:
>> > > 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@xxxxxxx>
>> > > Link: https://lore.kernel.org/r/7a1e2ebc-f7d8-8431-d844-41a9c36a8911@xxxxxxx
>> > > Suggested-by: Robin Murphy <robin.murphy@xxxxxxx>
>> > > Signed-off-by: Punit Agrawal <punitagrawal@xxxxxxxxx>
>> > > Tested-by: Alexandru Elisei <alexandru.elisei@xxxxxxx>
>> > > Cc: Heiko Stuebner <heiko@xxxxxxxxx>
>> > > Cc: Rob Herring <robh+dt@xxxxxxxxxx>
>> > just for clarity, should I just pick this patch separately for 5.13-rc to
>> > make it easy for people using current kernel devicetrees, or should
>> > this wait for the update mentioned in the cover-letter response
>> > and should go all together through the PCI tree?
>> This was dropped from v4, but should still be applied IMO.
> It was probably dropped because I applied it ;-)
> It's part of armsoc already  and should make its way into
> 5.13 shortly.
Thanks for sending the patch along. I left a note to the effect in v4
but it's easy to miss.
Hopefully all sorted now.