PCI: dwc: Skip PME_Turn_Off broadcast and L2/L3 transition during suspend if link...

During system suspend, if the PCIe link is not up, then there is no need
to broadcast PME_Turn_Off message and wait for L2/L3 transition. So skip
them.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Tested-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Link: https://patch.msgid.link/20251218-pci-dwc-suspend-rework-v2-1-5a7778c6094a@oss.qualcomm.com

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index ffc95ddcf3bf38629cc43be8282541095e024f39..8c41b90a1db1e3b92947238683714ab0b666efab 100644 (file)
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -1169,8 +1169,11 @@ static int dw_pcie_pme_turn_off(struct dw_pcie *pci)
 int dw_pcie_suspend_noirq(struct dw_pcie *pci)
 {
        u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
+       int ret = 0;
        u32 val;
-       int ret;
+
+       if (!dw_pcie_link_up(pci))
+               goto stop_link;
 
        /*
         * If L1SS is supported, then do not put the link into L2 as some
@@ -1205,6 +1208,7 @@ int dw_pcie_suspend_noirq(struct dw_pcie *pci)
         */
        udelay(1);
 
+stop_link:
        dw_pcie_stop_link(pci);
        if (pci->pp.ops->deinit)
                pci->pp.ops->deinit(&pci->pp);