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

[Jon Hunter <jonathanh@nvidia.com>]

On 05/01/2026 12:13, Niklas Cassel wrote:
> 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.

Looking 0c2228731974 ("phy: tegra: p2u: Broaden architecture
dependency") we ended up just merging ...

diff --git a/drivers/phy/tegra/Kconfig b/drivers/phy/tegra/Kconfig
index f30cfb42b210..342fb736da4b 100644
--- a/drivers/phy/tegra/Kconfig
+++ b/drivers/phy/tegra/Kconfig
@@ -13,7 +13,7 @@ config PHY_TEGRA_XUSB
  
  config PHY_TEGRA194_P2U
         tristate "NVIDIA Tegra194 PIPE2UPHY PHY driver"
-       depends on ARCH_TEGRA_194_SOC || ARCH_TEGRA_234_SOC || COMPILE_TEST
+       depends on ARCH_TEGRA || COMPILE_TEST
         select GENERIC_PHY
         help

So I guess we could just merge Francesco's original suggestion for
consistency. Otherwise I would be happy with ...

  depends on (ARCH_TEGRA && ARM64) || COMPILE_TEST

Jon

-- 
nvpublic