Merge tag 'msi-3.12' of git://git.infradead.org/linux-mvebu into next/drivers

From Jason Cooper:
mvebu msi pci changes for v3.12

 - introduce support for MSI on PCI
 - fix s390 build breakage when !HAVE_GENERIC_HARDIRQS

NOTE: This branch is a dependency for changes going though arm-soc from both
Thomas Petazzoni and Thierry Reding.

* tag 'msi-3.12' of git://git.infradead.org/linux-mvebu:
  PCI: msi: add default MSI operations for !HAVE_GENERIC_HARDIRQS platforms
  ARM: pci: add ->add_bus() and ->remove_bus() hooks to hw_pci
  of: pci: add registry of MSI chips
  PCI: Introduce new MSI chip infrastructure
  PCI: remove ARCH_SUPPORTS_MSI kconfig option
  PCI: use weak functions for MSI arch-specific functions

Signed-off-by: Olof Johansson <olof@lixom.net>

4 files changed, 108 insertions, 27 deletions

diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
index 42c687a820ac..e5ca00893c0c 100644
--- a/drivers/of/of_pci.c
+++ b/drivers/of/of_pci.c
@@ -89,3 +89,48 @@ int of_pci_parse_bus_range(struct device_node *node, struct resource *res)
         return 0;
 }
 EXPORT_SYMBOL_GPL(of_pci_parse_bus_range);
+
+#ifdef CONFIG_PCI_MSI
+
+static LIST_HEAD(of_pci_msi_chip_list);
+static DEFINE_MUTEX(of_pci_msi_chip_mutex);
+
+int of_pci_msi_chip_add(struct msi_chip *chip)
+{
+        if (!of_property_read_bool(chip->of_node, "msi-controller"))
+                return -EINVAL;
+
+        mutex_lock(&of_pci_msi_chip_mutex);
+        list_add(&chip->list, &of_pci_msi_chip_list);
+        mutex_unlock(&of_pci_msi_chip_mutex);
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(of_pci_msi_chip_add);
+
+void of_pci_msi_chip_remove(struct msi_chip *chip)
+{
+        mutex_lock(&of_pci_msi_chip_mutex);
+        list_del(&chip->list);
+        mutex_unlock(&of_pci_msi_chip_mutex);
+}
+EXPORT_SYMBOL_GPL(of_pci_msi_chip_remove);
+
+struct msi_chip *of_pci_find_msi_chip_by_node(struct device_node *of_node)
+{
+        struct msi_chip *c;
+
+        mutex_lock(&of_pci_msi_chip_mutex);
+        list_for_each_entry(c, &of_pci_msi_chip_list, list) {
+                if (c->of_node == of_node) {
+                        mutex_unlock(&of_pci_msi_chip_mutex);
+                        return c;
+                }
+        }
+        mutex_unlock(&of_pci_msi_chip_mutex);
+
+        return NULL;
+}
+EXPORT_SYMBOL_GPL(of_pci_find_msi_chip_by_node);
+
+#endif /* CONFIG_PCI_MSI */
diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index 81944fb73116..b6a99f7a9b20 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -1,13 +1,9 @@
 #
 # PCI configuration
 #
-config ARCH_SUPPORTS_MSI
-        bool
-
 config PCI_MSI
         bool "Message Signaled Interrupts (MSI and MSI-X)"
         depends on PCI
-        depends on ARCH_SUPPORTS_MSI
         help
            This allows device drivers to enable MSI (Message Signaled
            Interrupts).  Message Signaled Interrupts enable a device to
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index aca7578b05e5..b35f93c232cf 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -30,20 +30,60 @@ static int pci_msi_enable = 1;
 
 /* Arch hooks */
 
-#ifndef arch_msi_check_device
-int arch_msi_check_device(struct pci_dev *dev, int nvec, int type)
+#if defined(CONFIG_GENERIC_HARDIRQS)
+int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
 {
+        struct msi_chip *chip = dev->bus->msi;
+        int err;
+
+        if (!chip || !chip->setup_irq)
+                return -EINVAL;
+
+        err = chip->setup_irq(chip, dev, desc);
+        if (err < 0)
+                return err;
+
+        irq_set_chip_data(desc->irq, chip);
+
         return 0;
 }
-#endif
 
-#ifndef arch_setup_msi_irqs
-# define arch_setup_msi_irqs default_setup_msi_irqs
-# define HAVE_DEFAULT_MSI_SETUP_IRQS
-#endif
+void __weak arch_teardown_msi_irq(unsigned int irq)
+{
+        struct msi_chip *chip = irq_get_chip_data(irq);
 
-#ifdef HAVE_DEFAULT_MSI_SETUP_IRQS
-int default_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+        if (!chip || !chip->teardown_irq)
+                return;
+
+        chip->teardown_irq(chip, irq);
+}
+
+int __weak arch_msi_check_device(struct pci_dev *dev, int nvec, int type)
+{
+        struct msi_chip *chip = dev->bus->msi;
+
+        if (!chip || !chip->check_device)
+                return 0;
+
+        return chip->check_device(chip, dev, nvec, type);
+}
+#else
+int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
+{
+        return -ENOSYS;
+}
+
+void __weak arch_teardown_msi_irq(unsigned int irq)
+{
+}
+
+int __weak arch_msi_check_device(struct pci_dev *dev, int nvec, int type)
+{
+        return 0;
+}
+#endif /* CONFIG_GENERIC_HARDIRQS */
+
+int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 {
         struct msi_desc *entry;
         int ret;
@@ -65,14 +105,11 @@ int default_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 
         return 0;
 }
-#endif
-
-#ifndef arch_teardown_msi_irqs
-# define arch_teardown_msi_irqs default_teardown_msi_irqs
-# define HAVE_DEFAULT_MSI_TEARDOWN_IRQS
-#endif
 
-#ifdef HAVE_DEFAULT_MSI_TEARDOWN_IRQS
+/*
+ * We have a default implementation available as a separate non-weak
+ * function, as it is used by the Xen x86 PCI code
+ */
 void default_teardown_msi_irqs(struct pci_dev *dev)
 {
         struct msi_desc *entry;
@@ -89,14 +126,12 @@ void default_teardown_msi_irqs(struct pci_dev *dev)
                         arch_teardown_msi_irq(entry->irq + i);
         }
 }
-#endif
 
-#ifndef arch_restore_msi_irqs
-# define arch_restore_msi_irqs default_restore_msi_irqs
-# define HAVE_DEFAULT_MSI_RESTORE_IRQS
-#endif
+void __weak arch_teardown_msi_irqs(struct pci_dev *dev)
+{
+        return default_teardown_msi_irqs(dev);
+}
 
-#ifdef HAVE_DEFAULT_MSI_RESTORE_IRQS
 void default_restore_msi_irqs(struct pci_dev *dev, int irq)
 {
         struct msi_desc *entry;
@@ -114,7 +149,11 @@ void default_restore_msi_irqs(struct pci_dev *dev, int irq)
         if (entry)
                 write_msi_msg(irq, &entry->msg);
 }
-#endif
+
+void __weak arch_restore_msi_irqs(struct pci_dev *dev, int irq)
+{
+        return default_restore_msi_irqs(dev, irq);
+}
 
 static void msi_set_enable(struct pci_dev *dev, int enable)
 {
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 46ada5c098eb..b8eaa8167849 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -666,6 +666,7 @@ static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
 
         child->parent = parent;
         child->ops = parent->ops;
+        child->msi = parent->msi;
         child->sysdata = parent->sysdata;
         child->bus_flags = parent->bus_flags;