Re: [PATCH] PCI: spacemit: Ignore PERST# bit for controllers

[Ali Tariq <alitariq45892@gmail.com>]

On 11/4/26 7:14 PM, Troy Mitchell wrote:
> On Wed Nov 4, 2026 at 2:07 PM GMT, Ali Tariq wrote:
>> The k1_pcie_init() does not set PCIE_IGNORE_PERSTN bit of the
>> control logic register, which causes controller to reset itself once
>> PERST# signal is asserted even when acting as host.
>> On Orange Pi RV2 (SpacemiT K1), this resets the controller and wipes
>> the IDs. k1_pcie_deinit() leaves PERST# asserted, so when k1_pcie_init()
>> runs again, its first DBI access hangs the CPU.
>>
>> Set PCIE_IGNORE_PERSTN bit of the control logic register of APMU
>> in k1_pcie_init() before enabling resources so controllers
>> dont end up resetting themselves when PERST# signal is asserted.
>>
>> Fixes: ff64e078e45f ("PCI: spacemit: Add SpacemiT PCIe host driver")
>> Signed-off-by: Ali Tariq <alitariq45892@gmail.com>
>> ---
>> Hang log: https://kernelci.cloud-v.co/scheduler/job/420
>> Fixed Log: https://kernelci.cloud-v.co/scheduler/job/430
>> ---
>>   drivers/pci/controller/dwc/pcie-spacemit-k1.c | 9 +++++++++
>>   1 file changed, 9 insertions(+)
>>
>> diff --git a/drivers/pci/controller/dwc/pcie-spacemit-k1.c b/drivers/pci/controller/dwc/pcie-spacemit-k1.c
>> index 92a71ea90ac3..af6028e8825a 100644
>> --- a/drivers/pci/controller/dwc/pcie-spacemit-k1.c
>> +++ b/drivers/pci/controller/dwc/pcie-spacemit-k1.c
>> @@ -47,6 +47,7 @@
>>   
>>   #define PCIE_CONTROL_LOGIC			0x0004
>>   #define PCIE_SOFT_RESET			BIT(0)
>> +#define PCIE_IGNORE_PERSTN		BIT(2)	/* 1: ignore PERST# */
> A similar but earlier patch can be found here [1]
> 
> Link: https://lore.kernel.org/all/20260924-spacemit-k1-pcie-fix-v1-1-002b5c1ba9fc@linux.spacemit.com/ [1]
> 

Thank you for pointing.

I missed that. I will check that patch.

You can drop my patch.

Regards,
Ali