[PATCH v3 4/5] ACPI/PCI: Ignore _OSC DPC negotiation result if pcie_ports_dpc_native is set.

[sathyanarayanan . kuppuswamy]

From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppusw...@linux.intel.com>

pcie_ports_dpc_native is set only if user requests native handling
of PCIe DPC capability via pcie_port_setup command line option.
User input takes precedence over _OSC based control negotiation
result. So consider the _OSC negotiated result for DPC ownership
only if pcie_ports_dpc_native is unset.

Signed-off-by: Kuppuswamy Sathyanarayanan 
<sathyanarayanan.kuppusw...@linux.intel.com>
---
 drivers/acpi/pci_root.c | 2 ++
 include/linux/pci.h     | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index e0039ad3480a..f90dba464ec2 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -925,6 +925,8 @@ struct pci_bus *acpi_pci_root_create(struct acpi_pci_root 
*root,
                        host_bridge->native_pme = 0;
                if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
                        host_bridge->native_ltr = 0;
+       }
+       if (!pcie_ports_native && !pcie_ports_dpc_native) {
                if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL))
                        host_bridge->native_dpc = 0;
        }
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 83ce1cdf5676..07d4db97f5f4 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1547,9 +1547,11 @@ static inline int pci_irqd_intx_xlate(struct irq_domain 
*d,
 #ifdef CONFIG_PCIEPORTBUS
 extern bool pcie_ports_disabled;
 extern bool pcie_ports_native;
+extern bool pcie_ports_dpc_native;
 #else
 #define pcie_ports_disabled    true
 #define pcie_ports_native      false
+#define pcie_ports_dpc_native  false
 #endif
 
 #define PCIE_LINK_STATE_L0S            BIT(0)
-- 
2.17.1