PCI: Simplify hotplug mch quirk.

There is a very old quirk for the intel E7502 E7320 and E7525 memory
controller hubs that disables usage of msi interrupts on pcie hotplug
bridges of those devices, and disables changing the affinity of irqs.

Today all we have to do to disable msi on a specific device is to set
dev->no_msi, which is much more straightforward than the previous
logic.

The re-running of this fixup after pci hotplug happens below these
devices is totally bogus.  All of the state we change is pure software
state and we don't change the hardware at all.  Which means hotplug on
the lower devices doesn't have a chance to change this state.  So we
can safely remove the special case from the pciehp driver and the pcie
portdriver.

I suspect the special case was someone's expermental debug code that
slipped in. Certainly it isn't mentioned in commit
6fb8880a61510295aece04a542767161f624dffe aka BKrev:
41966101LJ_ogfOU0m2aE6teZfQnuQ where the code first appears.
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

drivers/pci/hotplug/pciehp_ctrl.c

@@ -246,11 +246,6 @@ static int board_added(struct slot *p_slot)
 		goto err_exit;
 	}
 
-	/*
-	 * Some PCI Express root ports require fixup after hot-plug operation.
-	 */
-	if (pcie_mch_quirk)
-		pci_fixup_device(pci_fixup_final, ctrl->pci_dev);
 	if (PWR_LED(ctrl))
   		p_slot->hpc_ops->green_led_on(p_slot);
 

drivers/pci/hotplug/pciehp_pci.c

@@ -285,11 +285,6 @@ int pciehp_unconfigure_device(struct slot *p_slot)
 		}
 		pci_dev_put(temp);
 	}
-	/*
-	 * Some PCI Express root ports require fixup after hot-plug operation.
-	 */
-	if (pcie_mch_quirk)
-		pci_fixup_device(pci_fixup_final, p_slot->ctrl->pci_dev);
 
 	return rc;
 }

drivers/pci/pci.h

@@ -134,7 +134,6 @@ static inline int pci_no_d1d2(struct pci_dev *dev)
 	return (dev->no_d1d2 || parent_dstates);
 
 }
-extern int pcie_mch_quirk;
 extern struct device_attribute pci_dev_attrs[];
 extern struct device_attribute dev_attr_cpuaffinity;
 extern struct device_attribute dev_attr_cpulistaffinity;

drivers/pci/pcie/portdrv_core.c

@@ -191,10 +191,6 @@ static int assign_interrupt_mode(struct pci_dev *dev, int *vectors, int mask)
 	int irq, interrupt_mode = PCIE_PORT_NO_IRQ;
 	int i;
 
-	/* Check MSI quirk */
-	if (port_data->port_type == PCIE_RC_PORT && pcie_mch_quirk)
-		goto Fallback;
-
 	/* Try to use MSI-X if supported */
 	if (!pcie_port_enable_msix(dev, vectors, mask))
 		return PCIE_PORT_MSIX_MODE;
@@ -203,7 +199,6 @@ static int assign_interrupt_mode(struct pci_dev *dev, int *vectors, int mask)
 	if (!pci_enable_msi(dev))
 		interrupt_mode = PCIE_PORT_MSI_MODE;
 
- Fallback:
 	if (interrupt_mode == PCIE_PORT_NO_IRQ && dev->pin)
 		interrupt_mode = PCIE_PORT_INTx_MODE;
 

drivers/pci/quirks.c

@@ -31,8 +31,6 @@ int isa_dma_bridge_buggy;
 EXPORT_SYMBOL(isa_dma_bridge_buggy);
 int pci_pci_problems;
 EXPORT_SYMBOL(pci_pci_problems);
-int pcie_mch_quirk;
-EXPORT_SYMBOL(pcie_mch_quirk);
 
 #ifdef CONFIG_PCI_QUIRKS
 /*
@@ -1500,7 +1498,8 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL,	PCI_DEVICE_ID_INTEL_EESSC,	quirk_a
 
 static void __devinit quirk_pcie_mch(struct pci_dev *pdev)
 {
-	pcie_mch_quirk = 1;
+	pci_msi_off(pdev);
+	pdev->no_msi = 1;
 }
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,	PCI_DEVICE_ID_INTEL_E7520_MCH,	quirk_pcie_mch);
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,	PCI_DEVICE_ID_INTEL_E7320_MCH,	quirk_pcie_mch);