Re: [PATCH 4/5] PCI: dwc: rcar-gen4: Handle PERST via reset subsystem

On 7/14/26 5:07 PM, Geert Uytterhoeven wrote:

Hello Geert,

>> +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> 
>> @@ -299,10 +300,27 @@ static void rcar_gen4_pcie_unprepare(struct rcar_gen4_pcie *rcar)
>>
>>   static int rcar_gen4_pcie_get_resources(struct rcar_gen4_pcie *rcar)
>>   {
>> +       struct device *dev = rcar->dw.dev;
>> +       struct reset_control *perst;
>> +
>>          rcar->phy_base = devm_platform_ioremap_resource_byname(rcar->pdev, "phy");
>>          if (IS_ERR(rcar->phy_base))
>>                  return PTR_ERR(rcar->phy_base);
>>
>> +       rcar->perst = NULL;
>> +       for_each_available_child_of_node_scoped(dev->of_node, of_port) {
>> +               perst = of_reset_control_get(of_port, "perst");
>> +               if (IS_ERR(perst)) {
>> +                       if (PTR_ERR(perst) != -EPROBE_DEFER)
>> +                               dev_err(dev, "Failed to get PERST#\n");
>> +                       return PTR_ERR(perst);
> 
> return dev_err_probe(...)?
> 
> This error condition is triggered on Sparrow Hawk and White Hawk,
> as their DTS does not have perst:
> 
>      pcie-rcar-gen4 e65d0000.pcie: Failed to get PERST#
>      pcie-rcar-gen4 e65d0000.pcie: probe with driver pcie-rcar-gen4
> failed with error -2
I switched to of_reset_control_get_optional_exclusive() and cleaned the 
reset handling further in V2.