[PATCH 2/2] PCI/DPC: Disable DPC when link is in L2/L3 ready, L2 and L3 state

[Kai-Heng Feng]

Since TLP and DLLP transmission is disabled for a Link in L2/L3 Ready,
L2 and L3, and DPC depends on AER, so also disable DPC here.

Signed-off-by: Kai-Heng Feng <kai.heng.f...@canonical.com>
---
 drivers/pci/pcie/dpc.c | 61 +++++++++++++++++++++++++++++++-----------
 1 file changed, 45 insertions(+), 16 deletions(-)

diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c
index 3e9afee02e8d1..9585c10b7c577 100644
--- a/drivers/pci/pcie/dpc.c
+++ b/drivers/pci/pcie/dpc.c
@@ -343,13 +343,34 @@ void pci_dpc_init(struct pci_dev *pdev)
        }
 }
 
+static void dpc_enable(struct pcie_device *dev)
+{
+       struct pci_dev *pdev = dev->port;
+       u16 ctl;
+
+       pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, &ctl);
+
+       ctl = (ctl & 0xfff4) | PCI_EXP_DPC_CTL_EN_FATAL | 
PCI_EXP_DPC_CTL_INT_EN;
+       pci_write_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, ctl);
+}
+
+static void dpc_disable(struct pcie_device *dev)
+{
+       struct pci_dev *pdev = dev->port;
+       u16 ctl;
+
+       pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, &ctl);
+       ctl &= ~(PCI_EXP_DPC_CTL_EN_FATAL | PCI_EXP_DPC_CTL_INT_EN);
+       pci_write_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, ctl);
+}
+
 #define FLAG(x, y) (((x) & (y)) ? '+' : '-')
 static int dpc_probe(struct pcie_device *dev)
 {
        struct pci_dev *pdev = dev->port;
        struct device *device = &dev->device;
        int status;
-       u16 ctl, cap;
+       u16 cap;
 
        if (!pcie_aer_is_native(pdev) && !pcie_ports_dpc_native)
                return -ENOTSUPP;
@@ -364,10 +385,7 @@ static int dpc_probe(struct pcie_device *dev)
        }
 
        pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CAP, &cap);
-       pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, &ctl);
-
-       ctl = (ctl & 0xfff4) | PCI_EXP_DPC_CTL_EN_FATAL | 
PCI_EXP_DPC_CTL_INT_EN;
-       pci_write_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, ctl);
+       dpc_enable(dev);
        pci_info(pdev, "enabled with IRQ %d\n", dev->irq);
 
        pci_info(pdev, "error containment capabilities: Int Msg #%d, RPExt%c 
PoisonedTLP%c SwTrigger%c RP PIO Log %d, DL_ActiveErr%c\n",
@@ -380,22 +398,33 @@ static int dpc_probe(struct pcie_device *dev)
        return status;
 }
 
-static void dpc_remove(struct pcie_device *dev)
+static int dpc_suspend(struct pcie_device *dev)
 {
-       struct pci_dev *pdev = dev->port;
-       u16 ctl;
+       dpc_disable(dev);
+       return 0;
+}
 
-       pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, &ctl);
-       ctl &= ~(PCI_EXP_DPC_CTL_EN_FATAL | PCI_EXP_DPC_CTL_INT_EN);
-       pci_write_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, ctl);
+static int dpc_resume(struct pcie_device *dev)
+{
+       dpc_enable(dev);
+       return 0;
+}
+
+static void dpc_remove(struct pcie_device *dev)
+{
+       dpc_disable(dev);
 }
 
 static struct pcie_port_service_driver dpcdriver = {
-       .name           = "dpc",
-       .port_type      = PCIE_ANY_PORT,
-       .service        = PCIE_PORT_SERVICE_DPC,
-       .probe          = dpc_probe,
-       .remove         = dpc_remove,
+       .name                   = "dpc",
+       .port_type              = PCIE_ANY_PORT,
+       .service                = PCIE_PORT_SERVICE_DPC,
+       .probe                  = dpc_probe,
+       .suspend                = dpc_suspend,
+       .resume                 = dpc_resume,
+       .runtime_suspend        = dpc_suspend,
+       .runtime_resume         = dpc_resume,
+       .remove                 = dpc_remove,
 };
 
 int __init pcie_dpc_init(void)
-- 
2.33.1