PCI/MSI: Initialize MSI capability for all architectures

1851617cd2da ("PCI/MSI: Disable MSI at enumeration even if kernel doesn't
support MSI") moved dev->msi_cap and dev->msix_cap initialization from the
pci_init_capabilities() path (used on all architectures) to the
pci_setup_device() path (not used on Open Firmware architectures).

This broke MSI or MSI-X on Open Firmware machines.  4d9aac397a5d
("powerpc/PCI: Disable MSI/MSI-X interrupts at PCI probe time in OF case")
fixed it for PowerPC but not for SPARC.

Set up MSI and MSI-X (initialize msi_cap and msix_cap and disable MSI and
MSI-X) in pci_init_capabilities() so all architectures do it the same way.

This reverts 4d9aac397a5d since this patch fixes the problem generically
for both PowerPC and SPARC.

[bhelgaas: changelog, make pci_msi_setup_pci_dev() static]
Fixes: 1851617cd2da ("PCI/MSI: Disable MSI at enumeration even if kernel doesn't support MSI")
Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index edb1984201e9..cd94737af8fd 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1145,7 +1145,7 @@ int pci_cfg_space_size(struct pci_dev *dev)
 
 #define LEGACY_IO_RESOURCE      (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
 
-void pci_msi_setup_pci_dev(struct pci_dev *dev)
+static void pci_msi_setup_pci_dev(struct pci_dev *dev)
 {
         /*
          * Disable the MSI hardware to avoid screaming interrupts
@@ -1212,8 +1212,6 @@ int pci_setup_device(struct pci_dev *dev)
         /* "Unknown power state" */
         dev->current_state = PCI_UNKNOWN;
 
-        pci_msi_setup_pci_dev(dev);
-
         /* Early fixups, before probing the BARs */
         pci_fixup_device(pci_fixup_early, dev);
         /* device class may be changed after fixup */
@@ -1606,6 +1604,9 @@ static void pci_init_capabilities(struct pci_dev *dev)
         /* MSI/MSI-X list */
         pci_msi_init_pci_dev(dev);
 
+        /* Setup MSI caps & disable MSI/MSI-X interrupts */
+        pci_msi_setup_pci_dev(dev);
+
         /* Buffers for saving PCIe and PCI-X capabilities */
         pci_allocate_cap_save_buffers(dev);