Re: [PATCH V2] PCI: Fix PCI bridges not to go to D3Hot on SPARC64

[John Paul Adrian Glaubitz]

Hi Rene,

On Wed, 2025-12-03 at 20:05 +0100, René Rebe wrote:
> Commit a5fb3ff63287 ("PCI: Allow PCI bridges to go to D3Hot on all
> non-x86") was bisected to break some SPARC64 systems, see two oopses
> below. Fix by not allowing D3Hot on sparc64 while this is being
> further analyzed.

I think your summary is still misleading as at least to me it sounds
like you are providing a patch that fixes the D3Hot state on SPARC64
while in reality you're actually blacklisting the D3 power state on
the platform.

I suggest something like:

"pci: Don't allow D3 power state on sparc64"

This would also match the description of pci_bridge_d3_possible():

/**
 * pci_bridge_d3_possible - Is it possible to put the bridge into D3
 * @bridge: Bridge to check
 *
 * Currently we only allow D3 for some PCIe ports and for Thunderbolt.
 *
 * Return: Whether it is possible to move the bridge to D3.
 *
 * The return value is guaranteed to be constant across the entire lifetime
 * of the bridge, including its hot-removal.
 */

The function pci_bridge_d3_possible() determines whether D3 is allowed
on a certain platform and by adding CONFIG_SPARC64 to the list, you are
explicitly disallowing the use of this power state.

Adrian

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