ARM: 7683/1: pci: add a align_resource hook
The PCI specifications says that an I/O region must be aligned on a 4
KB boundary, and a memory region aligned on a 1 MB boundary.
However, the Marvell PCIe interfaces rely on address decoding windows
(which allow to associate a range of physical addresses with a given
device). For PCIe memory windows, those windows are defined with a 1
MB granularity (which matches the PCI specs), but PCIe I/O windows can
only be defined with a 64 KB granularity, so they have to be 64 KB
aligned. We therefore need to tell the PCI core about this special
alignement requirement.
The PCI core already calls pcibios_align_resource() in the ARM PCI
core, specifically for such purposes. So this patch extends the ARM
PCI core so that it calls a ->align_resource() hook registered by the
PCI driver, exactly like the existing ->map_irq() and ->swizzle()
hooks.
A particular PCI driver can register a align_resource() hook, and do
its own specific alignement, depending on the specific constraints of
the underlying hardware.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/include/asm/mach/pci.h b/arch/arm/include/asm/mach/pci.h
index 5cf2e97..7d2c3c8 100644
--- a/arch/arm/include/asm/mach/pci.h
+++ b/arch/arm/include/asm/mach/pci.h
@@ -30,6 +30,11 @@
void (*postinit)(void);
u8 (*swizzle)(struct pci_dev *dev, u8 *pin);
int (*map_irq)(const struct pci_dev *dev, u8 slot, u8 pin);
+ resource_size_t (*align_resource)(struct pci_dev *dev,
+ const struct resource *res,
+ resource_size_t start,
+ resource_size_t size,
+ resource_size_t align);
};
/*
@@ -51,6 +56,12 @@
u8 (*swizzle)(struct pci_dev *, u8 *);
/* IRQ mapping */
int (*map_irq)(const struct pci_dev *, u8, u8);
+ /* Resource alignement requirements */
+ resource_size_t (*align_resource)(struct pci_dev *dev,
+ const struct resource *res,
+ resource_size_t start,
+ resource_size_t size,
+ resource_size_t align);
void *private_data; /* platform controller private data */
};