target/linux/mvebu/patches-3.10/0072-PCI-Introduce-new-MSI-chip-infrastructure.patch

   1 From 9c6ddccbbfaf789beccc6a1d87abe9bc60dc570f Mon Sep 17 00:00:00 2001
   2 From: Thierry Reding <thierry.reding@avionic-design.de>
   3 Date: Thu, 6 Jun 2013 18:20:29 +0200
   4 Subject: [PATCH 072/203] PCI: Introduce new MSI chip infrastructure
   5
   6 The new struct msi_chip is used to associated an MSI controller with a
   7 PCI bus. It is automatically handed down from the root to its children
   8 during bus enumeration.
   9
  10 This patch provides default (weak) implementations for the architecture-
  11 specific MSI functions (arch_setup_msi_irq(), arch_teardown_msi_irq()
  12 and arch_msi_check_device()) which check if a PCI device's bus has an
  13 attached MSI chip and forward the call appropriately.
  14
  15 Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
  16 Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
  17 Acked-by: Bjorn Helgaas <bhelgaas@google.com>
  18 Tested-by: Daniel Price <daniel.price@gmail.com>
  19 Tested-by: Thierry Reding <thierry.reding@gmail.com>
  20 ---
  21  drivers/pci/msi.c   | 27 +++++++++++++++++++++++++--
  22  drivers/pci/probe.c |  1 +
  23  include/linux/msi.h | 11 +++++++++++
  24  include/linux/pci.h |  1 +
  25  4 files changed, 38 insertions(+), 2 deletions(-)
  26
  27 --- a/drivers/pci/msi.c
  28 +++ b/drivers/pci/msi.c
  29 @@ -32,16 +32,39 @@ static int pci_msi_enable = 1;
  30
  31  int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
  32  {
  33 -       return -EINVAL;
  34 +       struct msi_chip *chip = dev->bus->msi;
  35 +       int err;
  36 +
  37 +       if (!chip || !chip->setup_irq)
  38 +               return -EINVAL;
  39 +
  40 +       err = chip->setup_irq(chip, dev, desc);
  41 +       if (err < 0)
  42 +               return err;
  43 +
  44 +       irq_set_chip_data(desc->irq, chip);
  45 +
  46 +       return 0;
  47  }
  48
  49  void __weak arch_teardown_msi_irq(unsigned int irq)
  50  {
  51 +       struct msi_chip *chip = irq_get_chip_data(irq);
  52 +
  53 +       if (!chip || !chip->teardown_irq)
  54 +               return;
  55 +
  56 +       chip->teardown_irq(chip, irq);
  57  }
  58
  59  int __weak arch_msi_check_device(struct pci_dev *dev, int nvec, int type)
  60  {
  61 -       return 0;
  62 +       struct msi_chip *chip = dev->bus->msi;
  63 +
  64 +       if (!chip || !chip->check_device)
  65 +               return 0;
  66 +
  67 +       return chip->check_device(chip, dev, nvec, type);
  68  }
  69
  70  int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
  71 --- a/drivers/pci/probe.c
  72 +++ b/drivers/pci/probe.c
  73 @@ -634,6 +634,7 @@ static struct pci_bus *pci_alloc_child_b
  74
  75         child->parent = parent;
  76         child->ops = parent->ops;
  77 +       child->msi = parent->msi;
  78         child->sysdata = parent->sysdata;
  79         child->bus_flags = parent->bus_flags;
  80
  81 --- a/include/linux/msi.h
  82 +++ b/include/linux/msi.h
  83 @@ -64,4 +64,15 @@ void arch_restore_msi_irqs(struct pci_de
  84  void default_teardown_msi_irqs(struct pci_dev *dev);
  85  void default_restore_msi_irqs(struct pci_dev *dev, int irq);
  86
  87 +struct msi_chip {
  88 +       struct module *owner;
  89 +       struct device *dev;
  90 +
  91 +       int (*setup_irq)(struct msi_chip *chip, struct pci_dev *dev,
  92 +                        struct msi_desc *desc);
  93 +       void (*teardown_irq)(struct msi_chip *chip, unsigned int irq);
  94 +       int (*check_device)(struct msi_chip *chip, struct pci_dev *dev,
  95 +                           int nvec, int type);
  96 +};
  97 +
  98  #endif /* LINUX_MSI_H */
  99 --- a/include/linux/pci.h
 100 +++ b/include/linux/pci.h
 101 @@ -432,6 +432,7 @@ struct pci_bus {
 102         struct resource busn_res;       /* bus numbers routed to this bus */
 103
 104         struct pci_ops  *ops;           /* configuration access functions */
 105 +       struct msi_chip *msi;           /* MSI controller */
 106         void            *sysdata;       /* hook for sys-specific extension */
 107         struct proc_dir_entry *procdir; /* directory entry in /proc/bus/pci */
 108