Use separate remove()/shutdown() callback, and don't disable pci device
during shutdown. This can avoid some poweroff/reboot failures.
The poweroff/reboot failures can easily reproduce on Loongson platforms.
I think this is not a Loongson-specific problem, instead, is a problem
related to some specific PCI hosts. On some x86 platforms, radeon/amdgpu
devices can cause the same problem, and commit faefba95c9e8ca3a523831c2e
("drm/amdgpu: just suspend the hw on pci shutdown") can resolve it.
Radeon driver is more difficult than amdgpu due to its confusing symbol
names, and I have maintained an out-of-tree patch for a long time [1].
Recently, we found more and more devices can cause the same problem, and
it is very difficult to modify all problematic drivers as radeon/amdgpu
does. So, I think modify the PCIe port driver is a simple and effective
way.
[1] https://github.com/chenhuacai/linux/commit/6612f9c1fc290d42a14618ce9a7d03014d8ebb1a
Signed-off-by: Huacai Chen <chenhc@xxxxxxxxxx>
---
drivers/pci/pcie/portdrv.h | 2 +-
drivers/pci/pcie/portdrv_core.c | 6 ++++--
drivers/pci/pcie/portdrv_pci.c | 15 +++++++++++++--
3 files changed, 18 insertions(+), 5 deletions(-)
diff --git a/drivers/pci/pcie/portdrv.h b/drivers/pci/pcie/portdrv.h
index af7cf23..22ba7b9 100644
--- a/drivers/pci/pcie/portdrv.h
+++ b/drivers/pci/pcie/portdrv.h
@@ -123,7 +123,7 @@ int pcie_port_device_resume(struct device *dev);
int pcie_port_device_runtime_suspend(struct device *dev);
int pcie_port_device_runtime_resume(struct device *dev);
#endif
-void pcie_port_device_remove(struct pci_dev *dev);
+void pcie_port_device_remove(struct pci_dev *dev, bool disable);
int __must_check pcie_port_bus_register(void);
void pcie_port_bus_unregister(void);
diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c
index 50a9522..aa165be 100644
--- a/drivers/pci/pcie/portdrv_core.c
+++ b/drivers/pci/pcie/portdrv_core.c
@@ -487,11 +487,13 @@ EXPORT_SYMBOL_GPL(pcie_port_find_device);
* Remove PCI Express port service devices associated with given port and
* disable MSI-X or MSI for the port.
*/
-void pcie_port_device_remove(struct pci_dev *dev)
+void pcie_port_device_remove(struct pci_dev *dev, bool disable)
{
device_for_each_child(&dev->dev, NULL, remove_iter);
pci_free_irq_vectors(dev);
- pci_disable_device(dev);
+
+ if (disable)
+ pci_disable_device(dev);
}
/**
diff --git a/drivers/pci/pcie/portdrv_pci.c b/drivers/pci/pcie/portdrv_pci.c
index 3acf151..fcd3d2e 100644
--- a/drivers/pci/pcie/portdrv_pci.c
+++ b/drivers/pci/pcie/portdrv_pci.c
@@ -142,7 +142,18 @@ static void pcie_portdrv_remove(struct pci_dev *dev)
pm_runtime_dont_use_autosuspend(&dev->dev);
}
- pcie_port_device_remove(dev);
+ pcie_port_device_remove(dev, true);
+}
+
+static void pcie_portdrv_shutdown(struct pci_dev *dev)
+{
+ if (pci_bridge_d3_possible(dev)) {
+ pm_runtime_forbid(&dev->dev);
+ pm_runtime_get_noresume(&dev->dev);
+ pm_runtime_dont_use_autosuspend(&dev->dev);
+ }
+
+ pcie_port_device_remove(dev, false);
}
static pci_ers_result_t pcie_portdrv_error_detected(struct pci_dev *dev,
@@ -211,7 +222,7 @@ static struct pci_driver pcie_portdriver = {
.probe = pcie_portdrv_probe,
.remove = pcie_portdrv_remove,
- .shutdown = pcie_portdrv_remove,
+ .shutdown = pcie_portdrv_shutdown,
.err_handler = &pcie_portdrv_err_handler,
--
2.7.0
