nvme-pci: Allow PCI bus-level PM to be used if ASPM is disabled

[linux.git] / drivers / nvme / host / pci.c

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index db160cee42ad178e02b11cc15bb0229a9417f118..108e109e99f1aceddce3c535c3e25079752204bf 100644 (file)
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -2846,7 +2846,7 @@ static int nvme_resume(struct device *dev)
        struct nvme_dev *ndev = pci_get_drvdata(to_pci_dev(dev));
        struct nvme_ctrl *ctrl = &ndev->ctrl;
 
-       if (pm_resume_via_firmware() || !ctrl->npss ||
+       if (ndev->last_ps == U32_MAX ||
            nvme_set_power_state(ctrl, ndev->last_ps) != 0)
                nvme_reset_ctrl(ctrl);
        return 0;
@@ -2859,6 +2859,8 @@ static int nvme_suspend(struct device *dev)
        struct nvme_ctrl *ctrl = &ndev->ctrl;
        int ret = -EBUSY;
 
+       ndev->last_ps = U32_MAX;
+
        /*
         * The platform does not remove power for a kernel managed suspend so
         * use host managed nvme power settings for lowest idle power if
@@ -2866,8 +2868,14 @@ static int nvme_suspend(struct device *dev)
         * shutdown.  But if the firmware is involved after the suspend or the
         * device does not support any non-default power states, shut down the
         * device fully.
+        *
+        * If ASPM is not enabled for the device, shut down the device and allow
+        * the PCI bus layer to put it into D3 in order to take the PCIe link
+        * down, so as to allow the platform to achieve its minimum low-power
+        * state (which may not be possible if the link is up).
         */
-       if (pm_suspend_via_firmware() || !ctrl->npss) {
+       if (pm_suspend_via_firmware() || !ctrl->npss ||
+           !pcie_aspm_enabled(pdev)) {
                nvme_dev_disable(ndev, true);
                return 0;
        }
@@ -2880,7 +2888,6 @@ static int nvme_suspend(struct device *dev)
            ctrl->state != NVME_CTRL_ADMIN_ONLY)
                goto unfreeze;
 
-       ndev->last_ps = 0;
        ret = nvme_get_power_state(ctrl, &ndev->last_ps);
        if (ret < 0)
                goto unfreeze;