arch/powerpc/kernel/msi.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright 2006-2007, Michael Ellerman, IBM Corporation.
   4  */
   5
   6 #include <linux/kernel.h>
   7 #include <linux/msi.h>
   8 #include <linux/pci.h>
   9
  10 #include <asm/machdep.h>
  11
  12 int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
  13 {
  14         struct pci_controller *phb = pci_bus_to_host(dev->bus);
  15
  16         if (!phb->controller_ops.setup_msi_irqs ||
  17             !phb->controller_ops.teardown_msi_irqs) {
  18                 pr_debug("msi: Platform doesn't provide MSI callbacks.\n");
  19                 return -ENOSYS;
  20         }
  21
  22         /* PowerPC doesn't support multiple MSI yet */
  23         if (type == PCI_CAP_ID_MSI && nvec > 1)
  24                 return 1;
  25
  26         return phb->controller_ops.setup_msi_irqs(dev, nvec, type);
  27 }
  28
  29 void arch_teardown_msi_irqs(struct pci_dev *dev)
  30 {
  31         struct pci_controller *phb = pci_bus_to_host(dev->bus);
  32
  33         /*
  34          * We can be called even when arch_setup_msi_irqs() returns -ENOSYS,
  35          * so check the pointer again.
  36          */
  37         if (phb->controller_ops.teardown_msi_irqs)
  38                 phb->controller_ops.teardown_msi_irqs(dev);
  39 }