xref: /linux/arch/powerpc/kernel/msi.c (revision bd628c1bed7902ec1f24ba0fe70758949146abbe)
1 /*
2  * Copyright 2006-2007, Michael Ellerman, IBM Corporation.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version
7  * 2 of the License, or (at your option) any later version.
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/msi.h>
12 #include <linux/pci.h>
13 
14 #include <asm/machdep.h>
15 
16 int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
17 {
18 	struct pci_controller *phb = pci_bus_to_host(dev->bus);
19 
20 	if (!phb->controller_ops.setup_msi_irqs ||
21 	    !phb->controller_ops.teardown_msi_irqs) {
22 		pr_debug("msi: Platform doesn't provide MSI callbacks.\n");
23 		return -ENOSYS;
24 	}
25 
26 	/* PowerPC doesn't support multiple MSI yet */
27 	if (type == PCI_CAP_ID_MSI && nvec > 1)
28 		return 1;
29 
30 	return phb->controller_ops.setup_msi_irqs(dev, nvec, type);
31 }
32 
33 void arch_teardown_msi_irqs(struct pci_dev *dev)
34 {
35 	struct pci_controller *phb = pci_bus_to_host(dev->bus);
36 
37 	/*
38 	 * We can be called even when arch_setup_msi_irqs() returns -ENOSYS,
39 	 * so check the pointer again.
40 	 */
41 	if (phb->controller_ops.teardown_msi_irqs)
42 		phb->controller_ops.teardown_msi_irqs(dev);
43 }
44