[PATCH 8/10] PCI / PCIe: Disable PCIe port services during port initialization

["Rafael J. Wysocki" <rjw@xxxxxxx>]

From: Rafael J. Wysocki <rjw@xxxxxxx>

In principle PCIe port services may be enabled by the BIOS, so it's
better to disable them during port initialization to avoid spurious
events from being generated.

Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx>
Reviewed-by: Hidetoshi Seto <seto.hidetoshi@xxxxxxxxxxxxxx>
---
 drivers/pci/pcie/portdrv_core.c |   29 ++++++++++++++++++++++++++---
 1 file changed, 26 insertions(+), 3 deletions(-)

Index: linux-2.6/drivers/pci/pcie/portdrv_core.c
===================================================================
--- linux-2.6.orig/drivers/pci/pcie/portdrv_core.c
+++ linux-2.6/drivers/pci/pcie/portdrv_core.c
@@ -259,20 +259,43 @@ static int get_port_device_capability(st
 	/* Hot-Plug Capable */
 	if ((cap_mask & PCIE_PORT_SERVICE_HP) && (reg16 & PCI_EXP_FLAGS_SLOT)) {
 		pci_read_config_dword(dev, pos + PCI_EXP_SLTCAP, &reg32);
-		if (reg32 & PCI_EXP_SLTCAP_HPC)
+		if (reg32 & PCI_EXP_SLTCAP_HPC) {
 			services |= PCIE_PORT_SERVICE_HP;
+			/*
+			 * Disable hot-plug interrupts in case they have been
+			 * enabled by the BIOS and the hot-plug service driver
+			 * is not loaded.
+			 */
+			pos += PCI_EXP_SLTCTL;
+			pci_read_config_word(dev, pos, &reg16);
+			reg16 &= ~(PCI_EXP_SLTCTL_CCIE | PCI_EXP_SLTCTL_HPIE);
+			pci_write_config_word(dev, pos, reg16);
+		}
 	}
 	/* AER capable */
 	if ((cap_mask & PCIE_PORT_SERVICE_AER)
-	    && pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR))
+	    && pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR)) {
 		services |= PCIE_PORT_SERVICE_AER;
+		/*
+		 * Disable AER on this port in case it's been enabled by the
+		 * BIOS (the AER service driver will enable it when necessary).
+		 */
+		pci_disable_pcie_error_reporting(dev);
+	}
 	/* VC support */
 	if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_VC))
 		services |= PCIE_PORT_SERVICE_VC;
 	/* Root ports are capable of generating PME too */
 	if ((cap_mask & PCIE_PORT_SERVICE_PME)
-	    && dev->pcie_type == PCI_EXP_TYPE_ROOT_PORT)
+	    && dev->pcie_type == PCI_EXP_TYPE_ROOT_PORT) {
 		services |= PCIE_PORT_SERVICE_PME;
+		/*
+		 * Disable PME interrupt on this port in case it's been enabled
+		 * by the BIOS (the PME service driver will enable it when
+		 * necessary).
+		 */
+		pcie_pme_interrupt_enable(dev, false);
+	}
 
 	return services;
 }

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