tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright (C) 2004 IBM
3 *
4 * Implements the generic device dma API for powerpc.
5 * the pci and vio busses
6 */
7#ifndef _ASM_DMA_MAPPING_H
8#define _ASM_DMA_MAPPING_H
9#ifdef __KERNEL__
10
11#include <linux/types.h>
12#include <linux/cache.h>
13/* need struct page definitions */
14#include <linux/mm.h>
15#include <linux/scatterlist.h>
16#include <linux/dma-debug.h>
17#include <asm/io.h>
18#include <asm/swiotlb.h>
19
20#ifdef CONFIG_PPC64
21#define DMA_ERROR_CODE (~(dma_addr_t)0x0)
22#endif
23
24/* Some dma direct funcs must be visible for use in other dma_ops */
25extern void *__dma_direct_alloc_coherent(struct device *dev, size_t size,
26 dma_addr_t *dma_handle, gfp_t flag,
27 unsigned long attrs);
28extern void __dma_direct_free_coherent(struct device *dev, size_t size,
29 void *vaddr, dma_addr_t dma_handle,
30 unsigned long attrs);
31extern int dma_direct_mmap_coherent(struct device *dev,
32 struct vm_area_struct *vma,
33 void *cpu_addr, dma_addr_t handle,
34 size_t size, unsigned long attrs);
35
36#ifdef CONFIG_NOT_COHERENT_CACHE
37/*
38 * DMA-consistent mapping functions for PowerPCs that don't support
39 * cache snooping. These allocate/free a region of uncached mapped
40 * memory space for use with DMA devices. Alternatively, you could
41 * allocate the space "normally" and use the cache management functions
42 * to ensure it is consistent.
43 */
44struct device;
45extern void *__dma_alloc_coherent(struct device *dev, size_t size,
46 dma_addr_t *handle, gfp_t gfp);
47extern void __dma_free_coherent(size_t size, void *vaddr);
48extern void __dma_sync(void *vaddr, size_t size, int direction);
49extern void __dma_sync_page(struct page *page, unsigned long offset,
50 size_t size, int direction);
51extern unsigned long __dma_get_coherent_pfn(unsigned long cpu_addr);
52
53#else /* ! CONFIG_NOT_COHERENT_CACHE */
54/*
55 * Cache coherent cores.
56 */
57
58#define __dma_alloc_coherent(dev, gfp, size, handle) NULL
59#define __dma_free_coherent(size, addr) ((void)0)
60#define __dma_sync(addr, size, rw) ((void)0)
61#define __dma_sync_page(pg, off, sz, rw) ((void)0)
62
63#endif /* ! CONFIG_NOT_COHERENT_CACHE */
64
65static inline unsigned long device_to_mask(struct device *dev)
66{
67 if (dev->dma_mask && *dev->dma_mask)
68 return *dev->dma_mask;
69 /* Assume devices without mask can take 32 bit addresses */
70 return 0xfffffffful;
71}
72
73/*
74 * Available generic sets of operations
75 */
76#ifdef CONFIG_PPC64
77extern struct dma_map_ops dma_iommu_ops;
78#endif
79extern struct dma_map_ops dma_direct_ops;
80
81static inline struct dma_map_ops *get_dma_ops(struct device *dev)
82{
83 /* We don't handle the NULL dev case for ISA for now. We could
84 * do it via an out of line call but it is not needed for now. The
85 * only ISA DMA device we support is the floppy and we have a hack
86 * in the floppy driver directly to get a device for us.
87 */
88 if (unlikely(dev == NULL))
89 return NULL;
90
91 return dev->archdata.dma_ops;
92}
93
94static inline void set_dma_ops(struct device *dev, struct dma_map_ops *ops)
95{
96 dev->archdata.dma_ops = ops;
97}
98
99/*
100 * get_dma_offset()
101 *
102 * Get the dma offset on configurations where the dma address can be determined
103 * from the physical address by looking at a simple offset. Direct dma and
104 * swiotlb use this function, but it is typically not used by implementations
105 * with an iommu.
106 */
107static inline dma_addr_t get_dma_offset(struct device *dev)
108{
109 if (dev)
110 return dev->archdata.dma_offset;
111
112 return PCI_DRAM_OFFSET;
113}
114
115static inline void set_dma_offset(struct device *dev, dma_addr_t off)
116{
117 if (dev)
118 dev->archdata.dma_offset = off;
119}
120
121/* this will be removed soon */
122#define flush_write_buffers()
123
124#define HAVE_ARCH_DMA_SET_MASK 1
125extern int dma_set_mask(struct device *dev, u64 dma_mask);
126
127extern int __dma_set_mask(struct device *dev, u64 dma_mask);
128extern u64 __dma_get_required_mask(struct device *dev);
129
130static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
131{
132#ifdef CONFIG_SWIOTLB
133 struct dev_archdata *sd = &dev->archdata;
134
135 if (sd->max_direct_dma_addr && addr + size > sd->max_direct_dma_addr)
136 return false;
137#endif
138
139 if (!dev->dma_mask)
140 return false;
141
142 return addr + size - 1 <= *dev->dma_mask;
143}
144
145static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
146{
147 return paddr + get_dma_offset(dev);
148}
149
150static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
151{
152 return daddr - get_dma_offset(dev);
153}
154
155#define ARCH_HAS_DMA_MMAP_COHERENT
156
157static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
158 enum dma_data_direction direction)
159{
160 BUG_ON(direction == DMA_NONE);
161 __dma_sync(vaddr, size, (int)direction);
162}
163
164#endif /* __KERNEL__ */
165#endif /* _ASM_DMA_MAPPING_H */