[PATCH v4 02/11] xen/arm: Add new device type for PCI

[Oleksandr Andrushchenko <andr2000@xxxxxxxxx>]

From: Oleksandr Andrushchenko <oleksandr_andrushchenko@xxxxxxxx>

Add new device type (DEV_PCI) to distinguish PCI devices from platform
DT devices, so some drivers, like IOMMU, can handle PCI devices
differently.

Also add a helper which is when given a struct device returns the
corresponding struct pci_dev which this device is a part of.

Because of the header cross-dependencies, e.g. we need both
struct pci_dev and struct arch_pci_dev at the same time, this cannot be
done with an inline.

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@xxxxxxxx>
Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>
---
Since v2:
 - !! dropped Stefano's r-b because of the changes
 - simplified dev_to_pci to use a single
   container_of(dev, struct pci_dev, arch.dev) (Jan)
Since v1:
 - Folded new device type (DEV_PCI) into this patch.
---
 xen/arch/arm/pci/pci.c       | 7 +++++++
 xen/include/asm-arm/device.h | 4 ++--
 xen/include/asm-arm/pci.h    | 7 +++++++
 3 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/xen/arch/arm/pci/pci.c b/xen/arch/arm/pci/pci.c
index 73540045d187..138da19284ab 100644
--- a/xen/arch/arm/pci/pci.c
+++ b/xen/arch/arm/pci/pci.c
@@ -27,6 +27,13 @@ int arch_pci_clean_pirqs(struct domain *d)
     return 0;
 }
 
+struct pci_dev *dev_to_pci(struct device *dev)
+{
+    ASSERT(dev->type == DEV_PCI);
+
+    return container_of(dev, struct pci_dev, arch.dev);
+}
+
 static int __init dt_pci_init(void)
 {
     struct dt_device_node *np;
diff --git a/xen/include/asm-arm/device.h b/xen/include/asm-arm/device.h
index ebe84ea853cd..7bf040560363 100644
--- a/xen/include/asm-arm/device.h
+++ b/xen/include/asm-arm/device.h
@@ -4,6 +4,7 @@
 enum device_type
 {
     DEV_DT,
+    DEV_PCI,
 };
 
 struct dev_archdata {
@@ -25,8 +26,7 @@ typedef struct device device_t;
 
 #include <xen/device_tree.h>
 
-/* TODO: Correctly implement dev_is_pci when PCI is supported on ARM */
-#define dev_is_pci(dev) ((void)(dev), 0)
+#define dev_is_pci(dev) ((dev)->type == DEV_PCI)
 #define dev_is_dt(dev)  ((dev)->type == DEV_DT)
 
 enum device_class
diff --git a/xen/include/asm-arm/pci.h b/xen/include/asm-arm/pci.h
index 7cb2e2f1edaf..603a1fc072d1 100644
--- a/xen/include/asm-arm/pci.h
+++ b/xen/include/asm-arm/pci.h
@@ -26,6 +26,13 @@ struct arch_pci_dev {
     struct device dev;
 };
 
+/*
+ * Because of the header cross-dependencies, e.g. we need both
+ * struct pci_dev and struct arch_pci_dev at the same time, this cannot be
+ * done with an inline here. Macro can be implemented, but looks scary.
+ */
+struct pci_dev *dev_to_pci(struct device *dev);
+
 /* Arch-specific MSI data for vPCI. */
 struct vpci_arch_msi {
 };
-- 
2.25.1