[PATCH v2 2/7] PCI: Add pcie_port_slot_emulated stub

[Jonathan Derrick <jonathan.derrick@linux.dev>]

Add the checks to allow an emulated slot. An emulated slot will use
native Hotplug, AER, and PME services. It also needs to specify itself
as a hotplug bridge in order for bridge sizing to account for hotplug
reserved windows.

Signed-off-by: Jonathan Derrick <jonathan.derrick@linux.dev>
---
 drivers/pci/pci-acpi.c          | 3 +++
 drivers/pci/pcie/portdrv_core.c | 9 ++++++---
 drivers/pci/probe.c             | 2 +-
 include/linux/pci.h             | 2 ++
 4 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index a46fec776ad7..77a3c9e39966 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -798,6 +798,9 @@ bool pciehp_is_native(struct pci_dev *bridge)
 	if (!IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
 		return false;
 
+	if (pcie_port_slot_emulated(bridge))
+		return true;
+
 	pcie_capability_read_dword(bridge, PCI_EXP_SLTCAP, &slot_cap);
 	if (!(slot_cap & PCI_EXP_SLTCAP_HPC))
 		return false;
diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c
index 1ac7fec47d6f..b3c1e7d4ff10 100644
--- a/drivers/pci/pcie/portdrv_core.c
+++ b/drivers/pci/pcie/portdrv_core.c
@@ -209,7 +209,8 @@ static int get_port_device_capability(struct pci_dev *dev)
 	int services = 0;
 
 	if (dev->is_hotplug_bridge &&
-	    (pcie_ports_native || host->native_pcie_hotplug)) {
+	    (pcie_ports_native || pcie_port_slot_emulated(dev) ||
+	     host->native_pcie_hotplug)) {
 		services |= PCIE_PORT_SERVICE_HP;
 
 		/*
@@ -222,14 +223,16 @@ static int get_port_device_capability(struct pci_dev *dev)
 
 #ifdef CONFIG_PCIEAER
 	if (dev->aer_cap && pci_aer_available() &&
-	    (pcie_ports_native || host->native_aer))
+	    (pcie_ports_native || pcie_port_slot_emulated(dev) ||
+	     host->native_aer))
 		services |= PCIE_PORT_SERVICE_AER;
 #endif
 
 	/* Root Ports and Root Complex Event Collectors may generate PMEs */
 	if ((pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT ||
 	     pci_pcie_type(dev) == PCI_EXP_TYPE_RC_EC) &&
-	    (pcie_ports_native || host->native_pme)) {
+	    (pcie_ports_native || pcie_port_slot_emulated(dev) ||
+	     host->native_pme)) {
 		services |= PCIE_PORT_SERVICE_PME;
 
 		/*
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index b66fa42c4b1f..86ac4d223eba 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1574,7 +1574,7 @@ void set_pcie_hotplug_bridge(struct pci_dev *pdev)
 	u32 reg32;
 
 	pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &reg32);
-	if (reg32 & PCI_EXP_SLTCAP_HPC)
+	if (reg32 & PCI_EXP_SLTCAP_HPC || pcie_port_slot_emulated(pdev))
 		pdev->is_hotplug_bridge = 1;
 }
 
diff --git a/include/linux/pci.h b/include/linux/pci.h
index ff47ef83ab38..09f704337955 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1655,6 +1655,8 @@ extern bool pcie_ports_native;
 #define pcie_ports_native	false
 #endif
 
+#define pcie_port_slot_emulated(dev) false
+
 #define PCIE_LINK_STATE_L0S		BIT(0)
 #define PCIE_LINK_STATE_L1		BIT(1)
 #define PCIE_LINK_STATE_CLKPM		BIT(2)
-- 
2.30.2