Re: [PATCH] PCI: imx6: Simplify Kconfig depends on

[Leonard Crestez <leonard.crestez@nxp.com>]

On 4/12/2019 9:03 PM, Trent Piepho wrote:
> On Fri, 2019-04-12 at 17:56 +0000, Leonard Crestez wrote:
>> On 3/26/19 8:19 PM, Lorenzo Pieralisi wrote:
>>> On Mon, Mar 11, 2019 at 06:59:28PM +0000, Leonard Crestez wrote:
>>>> In theory this driver can be used on imx6sx without enabling support for
>>>> imx6q or imx7d but the "depends on" condition doesn't allow that.
>>>>
>>>> Instead of making the condition even longer just make it depend on
>>>> "ARCH_MXC || COMPILE_TEST" instead.
>>>>
>>>> Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
>>>> ---
>>>>    drivers/pci/controller/dwc/Kconfig | 2 +-
>>>>    1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig
>>>> index 6ea74b1c0d94..21747fd0e799 100644
>>>> --- a/drivers/pci/controller/dwc/Kconfig
>>>> +++ b/drivers/pci/controller/dwc/Kconfig
>>>> @@ -88,11 +88,11 @@ config PCI_EXYNOS
>>>>            depends on PCI_MSI_IRQ_DOMAIN
>>>>            select PCIE_DW_HOST
>>>>
>>>>    config PCI_IMX6
>>>>            bool "Freescale i.MX6/7/8 PCIe controller"
>>>> - depends on SOC_IMX6Q || SOC_IMX7D || (ARM64 && ARCH_MXC) || COMPILE_TEST
>>>> + depends on ARCH_MXC || COMPILE_TEST
>>>>            depends on PCI_MSI_IRQ_DOMAIN
>>>>            select PCIE_DW_HOST
>>>
>>> If Lucas does not spot any problem with this patch I would request his
>>> ACK to merge it, thanks.
>>
>> Lucas: Can you please ack this? It's a bit old but applies cleanly and
>> resend shouldn't be required.
> 
> The IMX7s does not have a PCI-e controller.  The IMX7d does have one,
> but not the "s".
> 
> Enabling the controller driver on an IMX SoC that doesn't have it is
> not exactly the end of the world and having to keep adding new IMX SOCs
> to the list here is annoying.  So IMHO, it's ok to make this change
> even if the controller is allowed on a superset of the SoCs that have
> it.

There is no separate config option for IMX7S and I don't think it will 
be ever added. There is however a CONFIG_SOC_IMX6SX.

There were attempts to add "depends on"/"selected by" IMX8MQ to various 
drivers but arm64 maintainers disagreed. This is why this patch fixes 
the "depends on" list for 6sx pcie by dropping per-SOC logic on 32-bit 
arm as well.

People who want very small kernels for their boards will likely fiddle 
with their specific defconfig anyway so maybe complex logic in Kconfig 
is not very helpful.

--
Regards,
Leonard