linux/arch/arm64/include/asm/dma-mapping.h
Alexander Graf 1a9a0536d8 arm64: Allow for different DMA and CPU bus offsets
On arm64, all SoCs we supported so far either have an IOMMU or have bus
addresses equal to CPU addresses.

However, with the Raspberry Pi 3 coming up, this is no longer true. To
allow DMA to work with an AArch64 kernel on those devices, let's allow
devices to have DMA offsets again.

Signed-off-by: Alexander Graf <agraf@suse.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
2016-06-06 13:48:54 -07:00

104 lines
2.7 KiB
C

/*
* Copyright (C) 2012 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ASM_DMA_MAPPING_H
#define __ASM_DMA_MAPPING_H
#ifdef __KERNEL__
#include <linux/types.h>
#include <linux/vmalloc.h>
#include <xen/xen.h>
#include <asm/xen/hypervisor.h>
#define DMA_ERROR_CODE (~(dma_addr_t)0)
extern struct dma_map_ops dummy_dma_ops;
static inline struct dma_map_ops *__generic_dma_ops(struct device *dev)
{
if (dev && dev->archdata.dma_ops)
return dev->archdata.dma_ops;
/*
* We expect no ISA devices, and all other DMA masters are expected to
* have someone call arch_setup_dma_ops at device creation time.
*/
return &dummy_dma_ops;
}
static inline struct dma_map_ops *get_dma_ops(struct device *dev)
{
if (xen_initial_domain())
return xen_dma_ops;
else
return __generic_dma_ops(dev);
}
void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
const struct iommu_ops *iommu, bool coherent);
#define arch_setup_dma_ops arch_setup_dma_ops
#ifdef CONFIG_IOMMU_DMA
void arch_teardown_dma_ops(struct device *dev);
#define arch_teardown_dma_ops arch_teardown_dma_ops
#endif
/* do not use this function in a driver */
static inline bool is_device_dma_coherent(struct device *dev)
{
if (!dev)
return false;
return dev->archdata.dma_coherent;
}
static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
{
dma_addr_t dev_addr = (dma_addr_t)paddr;
return dev_addr - ((dma_addr_t)dev->dma_pfn_offset << PAGE_SHIFT);
}
static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
{
phys_addr_t paddr = (phys_addr_t)dev_addr;
return paddr + ((phys_addr_t)dev->dma_pfn_offset << PAGE_SHIFT);
}
static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
{
if (!dev->dma_mask)
return false;
return addr + size - 1 <= *dev->dma_mask;
}
static inline void dma_mark_clean(void *addr, size_t size)
{
}
/* Override for dma_max_pfn() */
static inline unsigned long dma_max_pfn(struct device *dev)
{
dma_addr_t dma_max = (dma_addr_t)*dev->dma_mask;
return (ulong)dma_to_phys(dev, dma_max) >> PAGE_SHIFT;
}
#define dma_max_pfn(dev) dma_max_pfn(dev)
#endif /* __KERNEL__ */
#endif /* __ASM_DMA_MAPPING_H */