x86/PCI: Expand the x86_msi_ops to have a restore MSIs.

The MSI restore function will become a function pointer in an
x86_msi_ops struct. It defaults to the implementation in the
io_apic.c and msi.c. We piggyback on the indirection mechanism
introduced by "x86: Introduce x86_msi_ops".

Cc: x86@kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: linux-pci@vger.kernel.org
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 27 insertions, 2 deletions

diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 82de95e..a825d78 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -86,6 +86,31 @@ void default_teardown_msi_irqs(struct pci_dev *dev)
 }
 #endif
 
+#ifndef arch_restore_msi_irqs
+# define arch_restore_msi_irqs default_restore_msi_irqs
+# define HAVE_DEFAULT_MSI_RESTORE_IRQS
+#endif
+
+#ifdef HAVE_DEFAULT_MSI_RESTORE_IRQS
+void default_restore_msi_irqs(struct pci_dev *dev, int irq)
+{
+	struct msi_desc *entry;
+
+	entry = NULL;
+	if (dev->msix_enabled) {
+		list_for_each_entry(entry, &dev->msi_list, list) {
+			if (irq == entry->irq)
+				break;
+		}
+	} else if (dev->msi_enabled)  {
+		entry = irq_get_msi_desc(irq);
+	}
+
+	if (entry)
+		write_msi_msg(irq, &entry->msg);
+}
+#endif
+
 static void msi_set_enable(struct pci_dev *dev, int pos, int enable)
 {
 	u16 control;
@@ -372,7 +397,7 @@ static void __pci_restore_msi_state(struct pci_dev *dev)
 
 	pci_intx_for_msi(dev, 0);
 	msi_set_enable(dev, pos, 0);
-	write_msi_msg(dev->irq, &entry->msg);
+	arch_restore_msi_irqs(dev, dev->irq);
 
 	pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
 	msi_mask_irq(entry, msi_capable_mask(control), entry->masked);
@@ -400,7 +425,7 @@ static void __pci_restore_msix_state(struct pci_dev *dev)
 	pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
 
 	list_for_each_entry(entry, &dev->msi_list, list) {
-		write_msi_msg(entry->irq, &entry->msg);
+		arch_restore_msi_irqs(dev, entry->irq);
 		msix_mask_irq(entry, entry->masked);
 	}