[PATCH v6 0/4] PCI: Add support for resetting the Root Ports in a platform specific way

[Niklas Cassel]

Hello Mani,

Sorry for the delayed reply.
I just came back from vacation.

On Thu, Jul 24, 2025 at 11:00:05AM +0530, Manivannan Sadhasivam wrote:
> On Fri, Jul 18, 2025 at 12:39:50PM GMT, Niklas Cassel wrote:
> > On Fri, Jul 18, 2025 at 12:28:44PM +0200, Niklas Cassel wrote:
> > > On Tue, Jul 15, 2025 at 07:51:03PM +0530, Manivannan Sadhasivam via B4 Relay wrote:
> > > 2) Testing link down reset:
> > > 
> > > selftests before link down reset:
> > > # FAILED: 14 / 16 tests passed.
> > > 
> > > ## On EP side:
> > > # echo 0 > /sys/kernel/config/pci_ep/controllers/a40000000.pcie-ep/start && \
> > >   sleep 0.1 && echo 1 > /sys/kernel/config/pci_ep/controllers/a40000000.pcie-ep/start
> > > 
> > > 
> > > [  111.137162] rockchip-dw-pcie a40000000.pcie: PCIE_CLIENT_INTR_STATUS_MISC: 0x4
> > > [  111.137881] rockchip-dw-pcie a40000000.pcie: LTSSM_STATUS: 0x0
> > > [  111.138432] rockchip-dw-pcie a40000000.pcie: hot reset or link-down reset
> > > [  111.139067] pcieport 0000:00:00.0: Recovering Root Port due to Link Down
> > > [  111.139686] pci-endpoint-test 0000:01:00.0: AER: can't recover (no error_detected callback)
> > > [  111.255407] rockchip-dw-pcie a40000000.pcie: PCIe Gen.3 x4 link up
> > > [  111.256019] rockchip-dw-pcie a40000000.pcie: Root Port reset completed
> > > [  111.383401] pcieport 0000:00:00.0: Root Port has been reset
> > > [  111.384060] pcieport 0000:00:00.0: AER: device recovery failed
> > > [  111.384582] rockchip-dw-pcie a40000000.pcie: PCIE_CLIENT_INTR_STATUS_MISC: 0x3
> > > [  111.385218] rockchip-dw-pcie a40000000.pcie: LTSSM_STATUS: 0x230011
> > > [  111.385771] rockchip-dw-pcie a40000000.pcie: Received Link up event. Starting enumeration!
> > > [  111.390866] pcieport 0000:00:00.0: bridge configuration invalid ([bus 00-00]), reconfiguring
> > > [  111.391650] pci_bus 0000:01: busn_res: [bus 01-ff] end is updated to 01
> > > 
> > > Basically all tests timeout
> > > # FAILED: 1 / 16 tests passed.
> > > 
> > > Which is the same as before this patch series.
> > 
> > The above was with CONFIG_PCIEAER=y
> > 
> 
> This is kind of expected since the pci_endpoint_test driver doesn't have the AER
> err_handlers defined.

I see.
Would be nice if we could add them then, so that we can verify that this
series is working as intended.


> 
> > Wilfred suggested that I tried without this config set.
> > 
> > However, doing so, I got the exact same result:
> > # FAILED: 1 / 16 tests passed.
> > 
> 
> Interesting. Could you please share the dmesg log like above.

It is looking exactly like the dmesg above

[   86.820059] rockchip-dw-pcie a40000000.pcie: PCIE_CLIENT_INTR_STATUS_MISC: 0x4
[   86.820791] rockchip-dw-pcie a40000000.pcie: LTSSM_STATUS: 0x0
[   86.821344] rockchip-dw-pcie a40000000.pcie: hot reset or link-down reset
[   86.821978] pcieport 0000:00:00.0: Recovering Root Port due to Link Down
[   87.040551] rockchip-dw-pcie a40000000.pcie: PCIe Gen.3 x4 link up
[   87.041138] rockchip-dw-pcie a40000000.pcie: Root Port reset completed
[   87.168378] pcieport 0000:00:00.0: Root Port has been reset
[   87.168882] rockchip-dw-pcie a40000000.pcie: PCIE_CLIENT_INTR_STATUS_MISC: 0x3
[   87.169519] rockchip-dw-pcie a40000000.pcie: LTSSM_STATUS: 0x230011
[   87.272463] rockchip-dw-pcie a40000000.pcie: Received Link up event. Starting enumeration!
[   87.277552] pcieport 0000:00:00.0: bridge configuration invalid ([bus 00-00]), reconfiguring
[   87.278314] pci_bus 0000:01: busn_res: [bus 01-ff] end is updated to 01

except that we don't get the:
> [  111.139686] pci-endpoint-test 0000:01:00.0: AER: can't recover (no error_detected callback)
> [  111.384060] pcieport 0000:00:00.0: AER: device recovery failed

prints.


Kind regards,
Niklas