Re: [PATCH v9 2/2] PCI: xilinx-cpm: Add support for PCIe RP PERST# signal
| Newsgroups | org.kernel.vger.linux-devicetree,org.kernel.vger.linux-pci |
|---|---|
| Message-ID | <[email protected]> |
> Add support for the PCIe Root Port PERST# signal using the GPIO > framework, along with the PCIe IP reset. This reset is managed > by the driver and occurs after the Initial Power Up sequence > (PCIe CEM r6.0, 2.2.1) is handled in hardware before the driver's > probe function is called. > > This is useful in warm reset scenarios where the power rails stay stable > and only PERST# is toggled. Applying both the IP reset and PERST# resets > the Root Port controller and Endpoint synchronously, improving > reliability and avoiding lane errors. > > Both the reset GPIO and the reset controller are optional to keep > backward compatibility with existing DTBs. Also add a PCIE_T_PERST_US > (100 us) macro in pci.h for the PERST# active time (PCIe CEM r6.0, > sec 2.11.2, "T_PERST"). > > As part of this, update the interrupt controller node parsing to use > of_get_child_by_name() instead of of_get_next_child(), since the PCIe > host bridge node now has multiple children. This ensures the correct > node is selected during initialization. > > Signed-off-by: Sai Krishna Musham <[email protected]> Sashiko has reviewed this patch and found no issues. It looks great! -- Sashiko AI review · https://sashiko.dev/#/patchset/[email protected]?part=2