[PATCH 3/5] PCI/ACPI: Tidy _OSC control bit checking

From: Bjorn Helgaas
Date: Wed Nov 25 2020 - 20:18:45 EST


From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>

Add OSC_OWNER() helper to prettify checking the _OSC control bits to learn
whether the platform has granted us control of PCI features. No functional
change intended.

[bhelgaas: split to separate patch, commit log]
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
---
drivers/acpi/pci_root.c | 29 +++++++++++++++++------------
1 file changed, 17 insertions(+), 12 deletions(-)

diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index c12b5fb3e8fb..6db071038fd5 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -876,6 +876,12 @@ static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
__acpi_pci_root_release_info(bridge->release_data);
}

+#define OSC_OWNER(ctrl, bit, flag) \
+ do { \
+ if (!(ctrl & bit)) \
+ flag = 0; \
+ } while (0)
+
struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
struct acpi_pci_root_ops *ops,
struct acpi_pci_root_info *info,
@@ -887,6 +893,7 @@ struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
struct pci_bus *bus;
struct pci_host_bridge *host_bridge;
union acpi_object *obj;
+ u32 ctrl;

info->root = root;
info->bridge = device;
@@ -912,18 +919,16 @@ struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
goto out_release_info;

host_bridge = to_pci_host_bridge(bus->bridge);
- if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
- host_bridge->native_pcie_hotplug = 0;
- if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL))
- host_bridge->native_shpc_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))
- host_bridge->native_pme = 0;
- if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
- host_bridge->native_ltr = 0;
- if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL))
- host_bridge->native_dpc = 0;
+
+ ctrl = root->osc_control_set;
+ OSC_OWNER(ctrl, OSC_PCI_EXPRESS_NATIVE_HP_CONTROL,
+ host_bridge->native_pcie_hotplug);
+ OSC_OWNER(ctrl, OSC_PCI_SHPC_NATIVE_HP_CONTROL,
+ host_bridge->native_shpc_hotplug);
+ OSC_OWNER(ctrl, OSC_PCI_EXPRESS_AER_CONTROL, host_bridge->native_aer);
+ OSC_OWNER(ctrl, OSC_PCI_EXPRESS_PME_CONTROL, host_bridge->native_pme);
+ OSC_OWNER(ctrl, OSC_PCI_EXPRESS_LTR_CONTROL, host_bridge->native_ltr);
+ OSC_OWNER(ctrl, OSC_PCI_EXPRESS_DPC_CONTROL, host_bridge->native_dpc);

/*
* Evaluate the "PCI Boot Configuration" _DSM Function. If it
--
2.25.1