Re: [PATCH v6 08/11] PCI: dwc: Invoke post_init in dw_pcie_resume_noirq()
From: Bjorn Helgaas <helgaas@kernel.org>
Date: 2026-01-08 21:50:07
Also in:
imx, linux-devicetree, linux-pci, lkml
On Wed, Oct 15, 2025 at 11:04:25AM +0800, Richard Zhu wrote:
If the ops has post_init callback, invoke it in dw_pcie_resume_noirq().
I'm trying to write the merge commit log for this branch, and I don't
quite understand this.
The effect is to apply the GEN3_ZRXDC_NONCOMPL workaround for the
ERR051586 erratum, and Mani added the hint that this enables REFCLK
during resume. But it seems weird that we apply a REFCLK workaround
after the link is already up.
During probe, .post_init() is run after pci_host_probe(), so we apply
the workaround after enumerating all the devices, which means REFCLK
must already be valid and the link is already up.
Is "enabling REFCLK" actually what imx_pcie_host_post_init() does?
Could the workaround be done in imx_pcie_host_init() before the link
is brought up? If it could, it looks like we wouldn't need
imx_pcie_host_post_init() at all.
For now, I put this in the merge commit log:
- Apply i.MX95 ERR051586 erratum workaround for REFCLK issue during
resume (Richard Zhu)
quoted hunk ↗ jump to hunk
--- drivers/pci/controller/dwc/pcie-designware-host.c | 3 +++ 1 file changed, 3 insertions(+)diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c index 20c9333bcb1c4..2b59e7d2e6179 100644 --- a/drivers/pci/controller/dwc/pcie-designware-host.c +++ b/drivers/pci/controller/dwc/pcie-designware-host.c@@ -1199,6 +1199,9 @@ int dw_pcie_resume_noirq(struct dw_pcie *pci) if (ret) return ret; + if (pci->pp.ops->post_init) + pci->pp.ops->post_init(&pci->pp); + return ret; } EXPORT_SYMBOL_GPL(dw_pcie_resume_noirq);-- 2.37.1