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

From: Niklas Cassel <cassel@kernel.org>
To: Shawn Lin <shawn.lin@rock-chips.com>
Cc: "Bjorn Helgaas" <bhelgaas@google.com>,
	"Lorenzo Pieralisi" <lpieralisi@kernel.org>,
	"Krzysztof Wilczyński" <kw@linux.com>,
	linux-pci@vger.kernel.org, linux-rockchip@lists.infradead.org
Subject: Re: [PATCH v2] PCI: dw-rockchip: Add system PM support
Date: Thu, 17 Apr 2025 12:51:15 +0200	[thread overview]
Message-ID: <aADdI7ByEImYy3Pq@ryzen> (raw)
In-Reply-To: <Z_5aib0WGKfIANj_@ryzen>

On Tue, Apr 15, 2025 at 03:09:29PM +0200, Niklas Cassel wrote:
> On Fri, Apr 11, 2025 at 02:14:08PM +0800, Shawn Lin wrote:

(snip)

> > +
> > +	rockchip_pcie_ltssm_enable_control_mode(rockchip, PCIE_CLIENT_RC_MODE);
> 
> Here you are setting PCIE_CLIENT_RC_MODE unconditionally.
> 
> I really don't think that you have tested these callbacks with EP mode.
> 
> If we look at pcie-qcom.c and pcie-qcom-ep.c, dev_pm_ops is defined in
> pcie-qcom.c, but not in pcie-qcom-ep.c.
> 
> Perhaps it is starting to be time to have two separate drivers also for
> rockchip?

Hmm.. looking at pcie-tegra194.c, they do still have both RC and EP in the
same file, but they simply return -ENOTSUPP in the EP case:
https://github.com/torvalds/linux/blob/v6.15-rc2/drivers/pci/controller/dwc/pcie-tegra194.c#L2381-L2384

Perhaps you could do something similar?

Kind regards,
Niklas