Merge tag 'x86-irq-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 irq updates from Thomas Gleixner:
 "Surgery of the MSI interrupt handling to prepare the support of
  upcoming devices which require non-PCI based MSI handling:

   - Cleanup historical leftovers all over the place

   - Rework the code to utilize more core functionality

   - Wrap XEN PCI/MSI interrupts into an irqdomain to make irqdomain
     assignment to PCI devices possible.

   - Assign irqdomains to PCI devices at initialization time which
     allows to utilize the full functionality of hierarchical
     irqdomains.

   - Remove arch_.*_msi_irq() functions from X86 and utilize the
     irqdomain which is assigned to the device for interrupt management.

   - Make the arch_.*_msi_irq() support conditional on a config switch
     and let the last few users select it"

* tag 'x86-irq-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
  PCI: MSI: Fix Kconfig dependencies for PCI_MSI_ARCH_FALLBACKS
  x86/apic/msi: Unbreak DMAR and HPET MSI
  iommu/amd: Remove domain search for PCI/MSI
  iommu/vt-d: Remove domain search for PCI/MSI[X]
  x86/irq: Make most MSI ops XEN private
  x86/irq: Cleanup the arch_*_msi_irqs() leftovers
  PCI/MSI: Make arch_.*_msi_irq[s] fallbacks selectable
  x86/pci: Set default irq domain in pcibios_add_device()
  iommm/amd: Store irq domain in struct device
  iommm/vt-d: Store irq domain in struct device
  x86/xen: Wrap XEN MSI management into irqdomain
  irqdomain/msi: Allow to override msi_domain_alloc/free_irqs()
  x86/xen: Consolidate XEN-MSI init
  x86/xen: Rework MSI teardown
  x86/xen: Make xen_msi_init() static and rename it to xen_hvm_msi_init()
  PCI/MSI: Provide pci_dev_has_special_msi_domain() helper
  PCI_vmd_Mark_VMD_irqdomain_with_DOMAIN_BUS_VMD_MSI
  irqdomain/msi: Provide DOMAIN_BUS_VMD_MSI
  x86/irq: Initialize PCI/MSI domain at PCI init time
  x86/pci: Reducde #ifdeffery in PCI init code
  ...

1 files changed, 17 insertions, 1 deletions

diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index df1d95913d4e..3507f456fcd0 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -19,6 +19,7 @@
 #include <asm/smp.h>
 #include <asm/pci_x86.h>
 #include <asm/setup.h>
+#include <asm/irqdomain.h>
 
 unsigned int pci_probe = PCI_PROBE_BIOS | PCI_PROBE_CONF1 | PCI_PROBE_CONF2 |
 				PCI_PROBE_MMCONF;
@@ -633,8 +634,9 @@ static void set_dev_domain_options(struct pci_dev *pdev)
 
 int pcibios_add_device(struct pci_dev *dev)
 {
-	struct setup_data *data;
 	struct pci_setup_rom *rom;
+	struct irq_domain *msidom;
+	struct setup_data *data;
 	u64 pa_data;
 
 	pa_data = boot_params.hdr.setup_data;
@@ -661,6 +663,20 @@ int pcibios_add_device(struct pci_dev *dev)
 		memunmap(data);
 	}
 	set_dev_domain_options(dev);
+
+	/*
+	 * Setup the initial MSI domain of the device. If the underlying
+	 * bus has a PCI/MSI irqdomain associated use the bus domain,
+	 * otherwise set the default domain. This ensures that special irq
+	 * domains e.g. VMD are preserved. The default ensures initial
+	 * operation if irq remapping is not active. If irq remapping is
+	 * active it will overwrite the domain pointer when the device is
+	 * associated to a remapping domain.
+	 */
+	msidom = dev_get_msi_domain(&dev->bus->dev);
+	if (!msidom)
+		msidom = x86_pci_msi_default_domain;
+	dev_set_msi_domain(&dev->dev, msidom);
 	return 0;
 }