[PATCH v2] PCI: dw-rockchip: Add system PM support

[Bjorn Helgaas]

On Fri, Apr 11, 2025 at 02:14:08PM +0800, Shawn Lin wrote:
> This patch adds system PM support for Rockchip platforms by adding .pme_turn_off
> and .get_ltssm hook and tries to reuse possible exist code.
> 
> It's tested on RK3576 EVB1 board with Some NVMes and PCIe-2-SATA/XHCI devices.
> And check the PCIe protocol analyzer to make sure the L2 process fits the spec.

Sorry I didn't see these before you fixed the 0-day bot issues.

Please wrap the above to fit in 75 columns to it doesn't wrap when
"git log" indents it.

> [    1.541394] nvme nvme0: missing or invalid SUBNQN field.
> [    1.548755] nvme nvme0: allocated 64 MiB host memory buffer (16 segments).
> [    1.562235] nvme nvme0: 8/0/0 default/read/poll queues
> [    1.563930] nvme nvme0: Ignoring bogus Namespace Identifiers
> 
> echo N > /sys/module/printk/parameters/console_suspend
> echo core > /sys/power/pm_test
> echo mem > /sys/power/state
> 
> [   58.443602] PM: suspend entry (deep)
> [   58.444005] Filesystems sync: 0.000 seconds
> [   58.445542] Freezing user space processes
> [   58.447096] Freezing user space processes completed (elapsed 0.001 seconds)
> [   58.447718] OOM killer disabled.
> [   58.448008] Freezing remaining freezable tasks
> [   58.449080] Freezing remaining freezable tasks completed (elapsed 0.000 seconds)
> 
> ...
> 
> [   58.797070] rockchip-dw-pcie 22400000.pcie: PCIe Gen.2 x1 link up
> [   58.835953] OOM killer enabled.
> [   58.836262] Restarting tasks ... done.
> [   58.839241] random: crng reseeded on system resumption
> [   58.840679] PM: suspend exit
> [   59.500036] nvme nvme0: 8/0/0 default/read/poll queues
> [   59.500909] nvme nvme0: Ignoring bogus Namespace Identifiers
> 
> time dd if=/dev/nvme0n1 of=/dev/null bs=1M count=1000
> 1000+0 records in
> 1000+0 records out
> real    0m 5.51s
> user    0m 0.00s
> sys     0m 0.71s

Please remove the timestamps because they are distracting details not
relevant to understanding the issue.

Indent all this quoted material two spaces because it's not part of
the narrative text.

There's no hurry; you can wait a few days to repost in case others
have more substantive comments.

Bjorn