On Thu, May 17, 2018 at 12:28:54PM +0300, Mika Westerberg wrote:
> Currently we request control of native PCIe hotplug unconditionally.
> That may cause problems because native PCIe hotplug events are handled
> by pciehp driver and if it is not enabled those events will be lost.
> Make this bit more robust and request control of native PCIe hotplug
> only if we are actually prepared to do so (pciehp driver is enabled).
>
> While there rename host->native_hotplug to host->native_pcie_hotplug
> because we do the same for SHPC hotplug in subsequent patches.
>
> Suggested-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> ---
> drivers/acpi/pci_root.c | 6 ++++--
> drivers/pci/pcie/portdrv_core.c | 2 +-
> drivers/pci/probe.c | 2 +-
> include/linux/pci.h | 2 +-
> 4 files changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
> index 0da18bde6a16..02ab96f00952 100644
> --- a/drivers/acpi/pci_root.c
> +++ b/drivers/acpi/pci_root.c
> @@ -29,6 +29,7 @@
> #include <linux/pci.h>
> #include <linux/pci-acpi.h>
> #include <linux/pci-aspm.h>
> +#include <linux/pci_hotplug.h>
> #include <linux/dmar.h>
> #include <linux/acpi.h>
> #include <linux/slab.h>
> @@ -472,9 +473,10 @@ static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm)
> }
>
> control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
> - | OSC_PCI_EXPRESS_NATIVE_HP_CONTROL
> | OSC_PCI_EXPRESS_PME_CONTROL;
>
> + if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
> + control |= OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
> if (pci_aer_available()) {
> if (aer_acpi_firmware_first())
> dev_info(&device->dev,
> @@ -900,7 +902,7 @@ struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
>
> host_bridge = to_pci_host_bridge(bus->bridge);
> if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
> - host_bridge->native_hotplug = 0;
> + host_bridge->native_pcie_hotplug = 0;
> if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL))
> host_bridge->native_aer = 0;
> if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL))
Rafael, I noticed that the PCI Firmware Spec, r3.2, sec 4.5.2.2, says
we're required to evaluate _OSC when resuming from S4. I don't see a
path where we do that today.
Am I missing it? If not, what resume hook do we need to use to do
this?
