linux_dsm_epyc7002/arch/arm64/include/asm/dma-mapping.h
Robin Murphy 90ac706e98 dma-mapping: factor out dummy DMA ops
The dummy DMA ops are currently used by arm64 for any device which has
an invalid ACPI description and is thus barred from using DMA due to not
knowing whether is is cache-coherent or not. Factor these out into
general dma-mapping code so that they can be referenced from other
common code paths. In the process, we can prune all the optional
callbacks which just do the same thing as the default behaviour, and
fill in .map_resource for completeness.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
[hch: moved to a separate source file]
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Tested-by: Jesper Dangaard Brouer <brouer@redhat.com>
Tested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-12-13 21:06:12 +01:00

56 lines
1.6 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>
static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
{
/*
* 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 &dma_dummy_ops;
}
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, it is only provided for
* arch/arm/mm/xen.c, which is used by arm64 as well.
*/
static inline bool is_device_dma_coherent(struct device *dev)
{
return dev->dma_coherent;
}
#endif /* __KERNEL__ */
#endif /* __ASM_DMA_MAPPING_H */