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charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Fri, Mar 22, 2024 at 05:08:22PM +0100, Niklas Cassel wrote: > On Thu, Mar 14, 2024 at 08:53:40PM +0530, Manivannan Sadhasivam wrote: > > All EP specific resources are enabled during PERST# deassert. As a counter > > operation, all resources should be disabled during PERST# assert. There is > > no point in skipping that if the link was not enabled. > > > > This will also result in enablement of the resources twice if PERST# got > > deasserted again. So remove the check from qcom_pcie_perst_assert() and > > disable all the resources unconditionally. > > > > Fixes: f55fee56a631 ("PCI: qcom-ep: Add Qualcomm PCIe Endpoint controller driver") > > Signed-off-by: Manivannan Sadhasivam > > --- > > drivers/pci/controller/dwc/pcie-qcom-ep.c | 6 ------ > > 1 file changed, 6 deletions(-) > > > > diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c > > index 2fb8c15e7a91..50b1635e3cbb 100644 > > --- a/drivers/pci/controller/dwc/pcie-qcom-ep.c > > +++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c > > @@ -500,12 +500,6 @@ static int qcom_pcie_perst_deassert(struct dw_pcie *pci) > > static void qcom_pcie_perst_assert(struct dw_pcie *pci) > > { > > struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci); > > - struct device *dev = pci->dev; > > - > > - if (pcie_ep->link_status == QCOM_PCIE_EP_LINK_DISABLED) { > > - dev_dbg(dev, "Link is already disabled\n"); > > - return; > > - } > > > > dw_pcie_ep_cleanup(&pci->ep); > > qcom_pcie_disable_resources(pcie_ep); > > Are you really sure that this is safe? > > I think I remember seeing some splat in dmesg if some clks, or maybe it > was regulators, got disabled while already being disabled. > > Perhaps you could test it by simply calling: > qcom_pcie_disable_resources(); > twice here, and see if you see and splat in dmesg. > Calling the disable_resources() function twice will definitely result in the splat. But here PERST# is level triggered, so I don't see how the EP can see assert twice. Am I missing something? - Mani -- மணிவண்ணன் சதாசிவம்