Extended IRQ resource type for nForce (Andrew de Quincey)

drivers/acpi/pci_link.c

@@ -315,6 +315,7 @@ acpi_pci_link_set (
 	struct acpi_buffer	buffer = {sizeof(resource)+1, &resource};
 	int			i = 0;
 	int			valid = 0;
+	int			resource_type = 0;
 
 	ACPI_FUNCTION_TRACE("acpi_pci_link_set");
 
@@ -338,20 +339,32 @@ acpi_pci_link_set (
 		}
 	}
 
+	/* If IRQ<=15, first try with a "normal" IRQ descriptor. If that fails, try with
+	 * an extended one */
+	if (irq <= 15) {
+		resource_type = ACPI_RSTYPE_IRQ;
+	} else {
+		resource_type = ACPI_RSTYPE_EXT_IRQ;
+	}
+
+retry_programming:
+   
 	memset(&resource, 0, sizeof(resource));
 
 	/* NOTE: PCI interrupts are always level / active_low / shared. But not all
 	   interrupts > 15 are PCI interrupts. Rely on the ACPI IRQ definition for 
 	   parameters */
-	if (irq <= 15) {
+	switch(resource_type) {
+	case ACPI_RSTYPE_IRQ:
 		resource.res.id = ACPI_RSTYPE_IRQ;
 		resource.res.length = sizeof(struct acpi_resource);
 		resource.res.data.irq.edge_level = link->irq.edge_level;
 		resource.res.data.irq.active_high_low = link->irq.active_high_low;
 		resource.res.data.irq.number_of_interrupts = 1;
 		resource.res.data.irq.interrupts[0] = irq;
-	}
-	else {
+		break;
+	   
+	case ACPI_RSTYPE_EXT_IRQ:
 		resource.res.id = ACPI_RSTYPE_EXT_IRQ;
 		resource.res.length = sizeof(struct acpi_resource);
 		resource.res.data.extended_irq.producer_consumer = ACPI_CONSUMER;
@@ -360,11 +373,21 @@ acpi_pci_link_set (
 		resource.res.data.extended_irq.number_of_interrupts = 1;
 		resource.res.data.extended_irq.interrupts[0] = irq;
 		/* ignore resource_source, it's optional */
+		break;
 	}
 	resource.end.id = ACPI_RSTYPE_END_TAG;
 
 	/* Attempt to set the resource */
 	status = acpi_set_current_resources(link->handle, &buffer);
+
+	/* if we failed and IRQ <= 15, try again with an extended descriptor */
+	if (ACPI_FAILURE(status) && (resource_type == ACPI_RSTYPE_IRQ)) {
+                resource_type = ACPI_RSTYPE_EXT_IRQ;
+                printk(PREFIX "Retrying with extended IRQ descriptor\n");
+                goto retry_programming;
+	}
+  
+	/* check for total failure */
 	if (ACPI_FAILURE(status)) {
 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _SRS\n"));
 		return_VALUE(-ENODEV);
@@ -479,14 +502,14 @@ static int acpi_pci_link_allocate(struct acpi_pci_link* link) {
 		irq = link->irq.possible[0];
 	}
 
-		/* 
-		 * Select the best IRQ.  This is done in reverse to promote 
-		 * the use of IRQs 9, 10, 11, and >15.
-		 */
-		for (i=(link->irq.possible_count-1); i>0; i--) {
-			if (acpi_irq_penalty[irq] > acpi_irq_penalty[link->irq.possible[i]])
-				irq = link->irq.possible[i];
-		}
+	/* 
+	 * Select the best IRQ.  This is done in reverse to promote 
+	 * the use of IRQs 9, 10, 11, and >15.
+	 */
+	for (i=(link->irq.possible_count-1); i>0; i--) {
+		if (acpi_irq_penalty[irq] > acpi_irq_penalty[link->irq.possible[i]])
+			irq = link->irq.possible[i];
+	}
 
 	/* Attempt to enable the link device at this IRQ. */
 	if (acpi_pci_link_set(link, irq)) {