Re: [PATCH] pci: controller: tegra194: remove dependency on Tegra194 SoC

[Niklas Cassel <cassel@kernel.org>]

On Mon, Jan 05, 2026 at 05:38:34PM +0530, Manivannan Sadhasivam wrote:
> On Mon, Jan 05, 2026 at 11:56:37AM +0000, Jon Hunter wrote:
> > 
> > 
> > On 05/01/2026 09:09, Niklas Cassel wrote:
> > > On Mon, Jan 05, 2026 at 02:09:34PM +0530, Manivannan Sadhasivam wrote:
> > > > On Fri, Jan 02, 2026 at 10:58:15AM +0000, Jon Hunter wrote:
> > > > > 
> > > > > On 23/12/2025 06:45, Manivannan Sadhasivam wrote:
> > > > > > On Wed, Nov 26, 2025 at 11:25:30AM +0100, Francesco Lavra wrote:
> > > > > > 
> > > > > > + Tegra maintainers
> > > > > > 
> > > > > > > This driver runs (for both host and endpoint operation) also on other Tegra
> > > > > > > SoCs (e.g. Tegra234).
> > > > > > > Replace the Kconfig dependency on ARCH_TEGRA_194_SOC with a more generic
> > > > > > > dependency on ARCH_TEGRA; in addition, amend the Kconfig help text to
> > > > > > > reflect the fact that this driver is no longer exclusive to Tegra194.
> > > > > > > 
> > > > > > 
> > > > > > I vaguely remember asking about this a while back during some other patch review
> > > > > > and I don't remember what we concluded.
> > > > > > > Thierry, Jon, thoughts?
> > > > > 
> > > > > So ARCH_TEGRA means that this can be enabled for the legacy 32-bit Tegra
> > > > > devices as well as the current 64-bit Tegra devices (such as Tegra194).
> > > > > Given that this driver is only used for Tegra194 and Tegra234, it seems it
> > > > > would be better to only enable this for Tegra194 and Tegra234 instead of any
> > > > > Tegra.
> > > > > 
> > > > 
> > > > The dependency means, whenever someone tries to enable PCIE_TEGRA194_HOST,
> > > > ARCH_TEGRA should be enabled. So as long as someone not trying to enable
> > > > PCIE_TEGRA194_HOST for 32bit Tegra systems, ARCH_TEGRA should work fine and
> > > > PCIE_TEGRA194_HOST is not selected by arch/arm/configs/tegra_defconfig. So I
> > > > don't see any blocker with this patch. In fact, many other archs do the same.
> > > > 
> > > > But I don't like extending the Kconfig with per SoC dependency as it won't
> > > > scale.
> > > 
> > > We already have a patch from Vidya:
> > > [PATCH V4] PCI: dwc: tegra194: Broaden architecture dependency
> > > that was sent 2025-05-08
> > > 
> > > Back then, the reason why it wasn't merged was because it required a
> > > similar change to the PHY driver to go in first:
> > > https://lore.kernel.org/linux-pci/174722268141.85510.14696275121588719556.b4-ty@kernel.org/
> > > 
> > > The PHY driver change was merged in v6.16:
> > > 0c2228731974 ("phy: tegra: p2u: Broaden architecture dependency")
> > > 
> > > So, I think we could just merge:
> > > https://lore.kernel.org/linux-pci/20250508051922.4134041-1-vidyas@nvidia.com/
> > > 
> > > (Assuming it still applies.)
> > 
> > Yes it does and applying Sagar's patch is fine with me. So it you want to
> > apply Sagar's patch please add my ...
> > 
> 
> Don't we need:
> 
> 	depends on (ARCH_TEGRA && ARM64) || COMPILE_TEST

This is exactly what I originally suggested to Vidya:
https://lore.kernel.org/linux-pci/Z6XjWJd9jm0HHNXW@ryzen/


> 
> in the above patch?

The above patch instead has:

depends on ARCH_TEGRA && (ARM64 || COMPILE_TEST)

I don't know why Vidya did not use my suggestion exactly, but I guess I
assumed that he had a reason not to use my suggestion exactly.


Kind regards,
Niklas