Re: [V5,03/13] PCI: tegra194: Don't force the device into the D0 state before L2
From: Jon Hunter
Date: Tue Feb 10 2026 - 12:12:50 EST
On 08/02/2026 18:07, Manikanta Maddireddy wrote:
From: Vidya Sagar <vidyas@xxxxxxxxxx>
As per PCIe CEM spec rev 4.0 ver 1.0 sec 2.3, the PCIe endpoint device
should be in D3 state to assert wake# pin. This takes precedence over PCI
Express Base r4.0 v1.0 September 27-2017, 5.2 Link State Power Management
which states that the device can be put into D0 state before taking the
link to L2 state. So, to enable the wake functionality for endpoints, do
not force the devices to D0 state before taking the link to L2 state.
There is no functional issue with the endpoints where the link doesn't go
into L2 state (the reason why the earlier change was made in the first
place) as the root port proceeds with the usual flow post PME timeout.
Fixes: 56e15a238d92 ("PCI: tegra: Add Tegra194 PCIe support")
Signed-off-by: Vidya Sagar <vidyas@xxxxxxxxxx>
Signed-off-by: Manikanta Maddireddy <mmaddireddy@xxxxxxxxxx>
---
V5:
* None
V4:
* None
V3:
* None
V2:
* None
For future reference, you can always just say ...
Changes V1 -> V5: None
Jon