dma-mapping: provide a generic dma-noncoherent implementation

Add a new dma_map_ops implementation that uses dma-direct for the
address mapping of streaming mappings, and which requires arch-specific
implemenations of coherent allocate/free.

Architectures have to provide flushing helpers to ownership trasnfers
to the device and/or CPU, and can provide optional implementations of
the coherent mmap functionality, and the cache_flush routines for
non-coherent long term allocations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alexey Brodkin <abrodkin@synopsys.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
This commit is contained in:
Christoph Hellwig 2018-04-16 15:24:51 +02:00
parent 35ddb69cd2
commit 782e6769c0
9 changed files with 192 additions and 5 deletions

View File

@ -4334,12 +4334,14 @@ W: http://git.infradead.org/users/hch/dma-mapping.git
S: Supported
F: lib/dma-debug.c
F: lib/dma-direct.c
F: lib/dma-noncoherent.c
F: lib/dma-virt.c
F: drivers/base/dma-mapping.c
F: drivers/base/dma-coherent.c
F: include/asm-generic/dma-mapping.h
F: include/linux/dma-direct.h
F: include/linux/dma-mapping.h
F: include/linux/dma-noncoherent.h
DME1737 HARDWARE MONITOR DRIVER
M: Juerg Haefliger <juergh@gmail.com>

View File

@ -4,7 +4,16 @@
static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
{
/*
* Use the non-coherent ops if available. If an architecture wants a
* more fine-grained selection of operations it will have to implement
* get_arch_dma_ops itself or use the per-device dma_ops.
*/
#ifdef CONFIG_DMA_NONCOHERENT_OPS
return &dma_noncoherent_ops;
#else
return &dma_direct_ops;
#endif
}
#endif /* _ASM_GENERIC_DMA_MAPPING_H */

View File

@ -59,6 +59,11 @@ void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
gfp_t gfp, unsigned long attrs);
void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
dma_addr_t dma_addr, unsigned long attrs);
dma_addr_t dma_direct_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size, enum dma_data_direction dir,
unsigned long attrs);
int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
enum dma_data_direction dir, unsigned long attrs);
int dma_direct_supported(struct device *dev, u64 mask);
int dma_direct_mapping_error(struct device *dev, dma_addr_t dma_addr);
#endif /* _LINUX_DMA_DIRECT_H */

View File

@ -136,6 +136,7 @@ struct dma_map_ops {
};
extern const struct dma_map_ops dma_direct_ops;
extern const struct dma_map_ops dma_noncoherent_ops;
extern const struct dma_map_ops dma_virt_ops;
#define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1))

View File

@ -0,0 +1,47 @@
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_DMA_NONCOHERENT_H
#define _LINUX_DMA_NONCOHERENT_H 1
#include <linux/dma-mapping.h>
void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
gfp_t gfp, unsigned long attrs);
void arch_dma_free(struct device *dev, size_t size, void *cpu_addr,
dma_addr_t dma_addr, unsigned long attrs);
#ifdef CONFIG_DMA_NONCOHERENT_MMAP
int arch_dma_mmap(struct device *dev, struct vm_area_struct *vma,
void *cpu_addr, dma_addr_t dma_addr, size_t size,
unsigned long attrs);
#else
#define arch_dma_mmap NULL
#endif /* CONFIG_DMA_NONCOHERENT_MMAP */
#ifdef CONFIG_DMA_NONCOHERENT_CACHE_SYNC
void arch_dma_cache_sync(struct device *dev, void *vaddr, size_t size,
enum dma_data_direction direction);
#else
#define arch_dma_cache_sync NULL
#endif /* CONFIG_DMA_NONCOHERENT_CACHE_SYNC */
#ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE
void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr,
size_t size, enum dma_data_direction dir);
#else
static inline void arch_sync_dma_for_device(struct device *dev,
phys_addr_t paddr, size_t size, enum dma_data_direction dir)
{
}
#endif /* ARCH_HAS_SYNC_DMA_FOR_DEVICE */
#ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU
void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr,
size_t size, enum dma_data_direction dir);
#else
static inline void arch_sync_dma_for_cpu(struct device *dev,
phys_addr_t paddr, size_t size, enum dma_data_direction dir)
{
}
#endif /* ARCH_HAS_SYNC_DMA_FOR_CPU */
#endif /* _LINUX_DMA_NONCOHERENT_H */

View File

@ -441,10 +441,30 @@ config ARCH_DMA_ADDR_T_64BIT
config IOMMU_HELPER
bool
config ARCH_HAS_SYNC_DMA_FOR_DEVICE
bool
config ARCH_HAS_SYNC_DMA_FOR_CPU
bool
select NEED_DMA_MAP_STATE
config DMA_DIRECT_OPS
bool
depends on HAS_DMA
config DMA_NONCOHERENT_OPS
bool
depends on HAS_DMA
select DMA_DIRECT_OPS
config DMA_NONCOHERENT_MMAP
bool
depends on DMA_NONCOHERENT_OPS
config DMA_NONCOHERENT_CACHE_SYNC
bool
depends on DMA_NONCOHERENT_OPS
config DMA_VIRT_OPS
bool
depends on HAS_DMA

View File

@ -30,6 +30,7 @@ lib-$(CONFIG_PRINTK) += dump_stack.o
lib-$(CONFIG_MMU) += ioremap.o
lib-$(CONFIG_SMP) += cpumask.o
lib-$(CONFIG_DMA_DIRECT_OPS) += dma-direct.o
lib-$(CONFIG_DMA_NONCOHERENT_OPS) += dma-noncoherent.o
lib-$(CONFIG_DMA_VIRT_OPS) += dma-virt.o
lib-y += kobject.o klist.o

View File

@ -128,7 +128,7 @@ void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
free_pages((unsigned long)cpu_addr, page_order);
}
static dma_addr_t dma_direct_map_page(struct device *dev, struct page *page,
dma_addr_t dma_direct_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size, enum dma_data_direction dir,
unsigned long attrs)
{
@ -139,8 +139,8 @@ static dma_addr_t dma_direct_map_page(struct device *dev, struct page *page,
return dma_addr;
}
static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
int nents, enum dma_data_direction dir, unsigned long attrs)
int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
enum dma_data_direction dir, unsigned long attrs)
{
int i;
struct scatterlist *sg;
@ -175,7 +175,7 @@ int dma_direct_supported(struct device *dev, u64 mask)
return 1;
}
static int dma_direct_mapping_error(struct device *dev, dma_addr_t dma_addr)
int dma_direct_mapping_error(struct device *dev, dma_addr_t dma_addr)
{
return dma_addr == DIRECT_MAPPING_ERROR;
}

102
lib/dma-noncoherent.c Normal file
View File

@ -0,0 +1,102 @@
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2018 Christoph Hellwig.
*
* DMA operations that map physical memory directly without providing cache
* coherence.
*/
#include <linux/export.h>
#include <linux/mm.h>
#include <linux/dma-direct.h>
#include <linux/dma-noncoherent.h>
#include <linux/scatterlist.h>
static void dma_noncoherent_sync_single_for_device(struct device *dev,
dma_addr_t addr, size_t size, enum dma_data_direction dir)
{
arch_sync_dma_for_device(dev, dma_to_phys(dev, addr), size, dir);
}
static void dma_noncoherent_sync_sg_for_device(struct device *dev,
struct scatterlist *sgl, int nents, enum dma_data_direction dir)
{
struct scatterlist *sg;
int i;
for_each_sg(sgl, sg, nents, i)
arch_sync_dma_for_device(dev, sg_phys(sg), sg->length, dir);
}
static dma_addr_t dma_noncoherent_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size, enum dma_data_direction dir,
unsigned long attrs)
{
dma_addr_t addr;
addr = dma_direct_map_page(dev, page, offset, size, dir, attrs);
if (!dma_mapping_error(dev, addr) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC))
arch_sync_dma_for_device(dev, page_to_phys(page) + offset,
size, dir);
return addr;
}
static int dma_noncoherent_map_sg(struct device *dev, struct scatterlist *sgl,
int nents, enum dma_data_direction dir, unsigned long attrs)
{
nents = dma_direct_map_sg(dev, sgl, nents, dir, attrs);
if (nents > 0 && !(attrs & DMA_ATTR_SKIP_CPU_SYNC))
dma_noncoherent_sync_sg_for_device(dev, sgl, nents, dir);
return nents;
}
#ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU
static void dma_noncoherent_sync_single_for_cpu(struct device *dev,
dma_addr_t addr, size_t size, enum dma_data_direction dir)
{
arch_sync_dma_for_cpu(dev, dma_to_phys(dev, addr), size, dir);
}
static void dma_noncoherent_sync_sg_for_cpu(struct device *dev,
struct scatterlist *sgl, int nents, enum dma_data_direction dir)
{
struct scatterlist *sg;
int i;
for_each_sg(sgl, sg, nents, i)
arch_sync_dma_for_cpu(dev, sg_phys(sg), sg->length, dir);
}
static void dma_noncoherent_unmap_page(struct device *dev, dma_addr_t addr,
size_t size, enum dma_data_direction dir, unsigned long attrs)
{
if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
dma_noncoherent_sync_single_for_cpu(dev, addr, size, dir);
}
static void dma_noncoherent_unmap_sg(struct device *dev, struct scatterlist *sgl,
int nents, enum dma_data_direction dir, unsigned long attrs)
{
if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
dma_noncoherent_sync_sg_for_cpu(dev, sgl, nents, dir);
}
#endif
const struct dma_map_ops dma_noncoherent_ops = {
.alloc = arch_dma_alloc,
.free = arch_dma_free,
.mmap = arch_dma_mmap,
.sync_single_for_device = dma_noncoherent_sync_single_for_device,
.sync_sg_for_device = dma_noncoherent_sync_sg_for_device,
.map_page = dma_noncoherent_map_page,
.map_sg = dma_noncoherent_map_sg,
#ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU
.sync_single_for_cpu = dma_noncoherent_sync_single_for_cpu,
.sync_sg_for_cpu = dma_noncoherent_sync_sg_for_cpu,
.unmap_page = dma_noncoherent_unmap_page,
.unmap_sg = dma_noncoherent_unmap_sg,
#endif
.dma_supported = dma_direct_supported,
.mapping_error = dma_direct_mapping_error,
.cache_sync = arch_dma_cache_sync,
};
EXPORT_SYMBOL(dma_noncoherent_ops);