1 # SPDX-License-Identifier: GPL-2.0-only 1 # SPDX-License-Identifier: GPL-2.0-only
2 2
3 config NO_DMA 3 config NO_DMA
4 bool 4 bool
5 5
6 config HAS_DMA 6 config HAS_DMA
7 bool 7 bool
8 depends on !NO_DMA 8 depends on !NO_DMA
9 default y 9 default y
10 10
11 config DMA_OPS 11 config DMA_OPS
12 depends on HAS_DMA 12 depends on HAS_DMA
13 bool 13 bool
14 14
15 # 15 #
16 # IOMMU drivers that can bypass the IOMMU code 16 # IOMMU drivers that can bypass the IOMMU code and optionally use the direct
17 # mapping fast path should select this option 17 # mapping fast path should select this option and set the dma_ops_bypass
18 # flag in struct device where applicable 18 # flag in struct device where applicable
19 # 19 #
20 config DMA_OPS_BYPASS 20 config DMA_OPS_BYPASS
21 bool 21 bool
22 22
23 # Lets platform IOMMU driver choose between by 23 # Lets platform IOMMU driver choose between bypass and IOMMU
24 config ARCH_HAS_DMA_MAP_DIRECT 24 config ARCH_HAS_DMA_MAP_DIRECT
25 bool 25 bool
26 26
27 config NEED_SG_DMA_FLAGS 27 config NEED_SG_DMA_FLAGS
28 bool 28 bool
29 29
30 config NEED_SG_DMA_LENGTH 30 config NEED_SG_DMA_LENGTH
31 bool 31 bool
32 32
33 config NEED_DMA_MAP_STATE 33 config NEED_DMA_MAP_STATE
34 bool 34 bool
35 35
36 config ARCH_DMA_ADDR_T_64BIT 36 config ARCH_DMA_ADDR_T_64BIT
37 def_bool 64BIT || PHYS_ADDR_T_64BIT 37 def_bool 64BIT || PHYS_ADDR_T_64BIT
38 38
39 config ARCH_HAS_DMA_SET_MASK 39 config ARCH_HAS_DMA_SET_MASK
40 bool 40 bool
41 41
42 # 42 #
43 # Select this option if the architecture needs 43 # Select this option if the architecture needs special handling for
44 # DMA_ATTR_WRITE_COMBINE. Normally the "uncac 44 # DMA_ATTR_WRITE_COMBINE. Normally the "uncached" mapping should be what
45 # people think of when saying write combine, s 45 # people think of when saying write combine, so very few platforms should
46 # need to enable this. 46 # need to enable this.
47 # 47 #
48 config ARCH_HAS_DMA_WRITE_COMBINE 48 config ARCH_HAS_DMA_WRITE_COMBINE
49 bool 49 bool
50 50
51 # 51 #
52 # Select if the architectures provides the arc 52 # Select if the architectures provides the arch_dma_mark_clean hook
53 # 53 #
54 config ARCH_HAS_DMA_MARK_CLEAN 54 config ARCH_HAS_DMA_MARK_CLEAN
55 bool 55 bool
56 56
57 config DMA_DECLARE_COHERENT 57 config DMA_DECLARE_COHERENT
58 bool 58 bool
59 59
60 config ARCH_HAS_SETUP_DMA_OPS 60 config ARCH_HAS_SETUP_DMA_OPS
61 bool 61 bool
62 62
63 config ARCH_HAS_TEARDOWN_DMA_OPS 63 config ARCH_HAS_TEARDOWN_DMA_OPS
64 bool 64 bool
65 65
66 config ARCH_HAS_SYNC_DMA_FOR_DEVICE 66 config ARCH_HAS_SYNC_DMA_FOR_DEVICE
67 bool 67 bool
68 68
69 config ARCH_HAS_SYNC_DMA_FOR_CPU 69 config ARCH_HAS_SYNC_DMA_FOR_CPU
70 bool 70 bool
71 select NEED_DMA_MAP_STATE 71 select NEED_DMA_MAP_STATE
72 72
73 config ARCH_HAS_SYNC_DMA_FOR_CPU_ALL 73 config ARCH_HAS_SYNC_DMA_FOR_CPU_ALL
74 bool 74 bool
75 75
76 config ARCH_HAS_DMA_PREP_COHERENT 76 config ARCH_HAS_DMA_PREP_COHERENT
77 bool 77 bool
78 78
79 config ARCH_HAS_FORCE_DMA_UNENCRYPTED 79 config ARCH_HAS_FORCE_DMA_UNENCRYPTED
80 bool 80 bool
81 81
82 # 82 #
83 # Select this option if the architecture assum 83 # Select this option if the architecture assumes DMA devices are coherent
84 # by default. 84 # by default.
85 # 85 #
86 config ARCH_DMA_DEFAULT_COHERENT 86 config ARCH_DMA_DEFAULT_COHERENT
87 bool 87 bool
88 88
89 config SWIOTLB 89 config SWIOTLB
90 bool 90 bool
91 select NEED_DMA_MAP_STATE 91 select NEED_DMA_MAP_STATE
92 92
93 config SWIOTLB_DYNAMIC 93 config SWIOTLB_DYNAMIC
94 bool "Dynamic allocation of DMA bounce 94 bool "Dynamic allocation of DMA bounce buffers"
95 default n 95 default n
96 depends on SWIOTLB 96 depends on SWIOTLB
97 help 97 help
98 This enables dynamic resizing of the 98 This enables dynamic resizing of the software IO TLB. The kernel
99 starts with one memory pool at boot 99 starts with one memory pool at boot and it will allocate additional
100 pools as needed. To reduce run-time 100 pools as needed. To reduce run-time kernel memory requirements, you
101 may have to specify a smaller size o 101 may have to specify a smaller size of the initial pool using
102 "swiotlb=" on the kernel command lin 102 "swiotlb=" on the kernel command line.
103 103
104 If unsure, say N. 104 If unsure, say N.
105 105
106 config DMA_BOUNCE_UNALIGNED_KMALLOC 106 config DMA_BOUNCE_UNALIGNED_KMALLOC
107 bool 107 bool
108 depends on SWIOTLB 108 depends on SWIOTLB
109 109
110 config DMA_NEED_SYNC 110 config DMA_NEED_SYNC
111 def_bool ARCH_HAS_SYNC_DMA_FOR_DEVICE 111 def_bool ARCH_HAS_SYNC_DMA_FOR_DEVICE || ARCH_HAS_SYNC_DMA_FOR_CPU || \
112 ARCH_HAS_SYNC_DMA_FOR_CPU_ALL 112 ARCH_HAS_SYNC_DMA_FOR_CPU_ALL || DMA_API_DEBUG || DMA_OPS || \
113 SWIOTLB 113 SWIOTLB
114 114
115 config DMA_RESTRICTED_POOL 115 config DMA_RESTRICTED_POOL
116 bool "DMA Restricted Pool" 116 bool "DMA Restricted Pool"
117 depends on OF && OF_RESERVED_MEM && SW 117 depends on OF && OF_RESERVED_MEM && SWIOTLB
118 help 118 help
119 This enables support for restricted 119 This enables support for restricted DMA pools which provide a level of
120 DMA memory protection on systems wit 120 DMA memory protection on systems with limited hardware protection
121 capabilities, such as those lacking 121 capabilities, such as those lacking an IOMMU.
122 122
123 For more information see 123 For more information see
124 <Documentation/devicetree/bindings/r 124 <Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt>
125 and <kernel/dma/swiotlb.c>. 125 and <kernel/dma/swiotlb.c>.
126 If unsure, say "n". 126 If unsure, say "n".
127 127
128 # 128 #
129 # Should be selected if we can mmap non-cohere 129 # Should be selected if we can mmap non-coherent mappings to userspace.
130 # The only thing that is really required is a 130 # The only thing that is really required is a way to set an uncached bit
131 # in the pagetables 131 # in the pagetables
132 # 132 #
133 config DMA_NONCOHERENT_MMAP 133 config DMA_NONCOHERENT_MMAP
134 default y if !MMU 134 default y if !MMU
135 bool 135 bool
136 136
137 config DMA_COHERENT_POOL 137 config DMA_COHERENT_POOL
138 select GENERIC_ALLOCATOR 138 select GENERIC_ALLOCATOR
139 bool 139 bool
140 140
141 config DMA_GLOBAL_POOL 141 config DMA_GLOBAL_POOL
142 select DMA_DECLARE_COHERENT 142 select DMA_DECLARE_COHERENT
143 depends on !ARCH_HAS_DMA_SET_UNCACHED 143 depends on !ARCH_HAS_DMA_SET_UNCACHED
144 depends on !DMA_DIRECT_REMAP 144 depends on !DMA_DIRECT_REMAP
145 bool 145 bool
146 146
147 config DMA_DIRECT_REMAP 147 config DMA_DIRECT_REMAP
148 bool 148 bool
149 select DMA_COHERENT_POOL 149 select DMA_COHERENT_POOL
150 select DMA_NONCOHERENT_MMAP 150 select DMA_NONCOHERENT_MMAP
151 151
152 # 152 #
153 # Fallback to arch code for DMA allocations. 153 # Fallback to arch code for DMA allocations. This should eventually go away.
154 # 154 #
155 config ARCH_HAS_DMA_ALLOC 155 config ARCH_HAS_DMA_ALLOC
156 depends on !ARCH_HAS_DMA_SET_UNCACHED 156 depends on !ARCH_HAS_DMA_SET_UNCACHED
157 depends on !DMA_DIRECT_REMAP 157 depends on !DMA_DIRECT_REMAP
158 depends on !DMA_GLOBAL_POOL 158 depends on !DMA_GLOBAL_POOL
159 bool 159 bool
160 160
161 config DMA_CMA 161 config DMA_CMA
162 bool "DMA Contiguous Memory Allocator" 162 bool "DMA Contiguous Memory Allocator"
163 depends on HAVE_DMA_CONTIGUOUS && CMA 163 depends on HAVE_DMA_CONTIGUOUS && CMA
164 help 164 help
165 This enables the Contiguous Memory A 165 This enables the Contiguous Memory Allocator which allows drivers
166 to allocate big physically-contiguou 166 to allocate big physically-contiguous blocks of memory for use with
167 hardware components that do not supp 167 hardware components that do not support I/O map nor scatter-gather.
168 168
169 You can disable CMA by specifying "c 169 You can disable CMA by specifying "cma=0" on the kernel's command
170 line. 170 line.
171 171
172 For more information see <kernel/dma 172 For more information see <kernel/dma/contiguous.c>.
173 If unsure, say "n". 173 If unsure, say "n".
174 174
175 if DMA_CMA 175 if DMA_CMA
176 176
177 config DMA_NUMA_CMA 177 config DMA_NUMA_CMA
178 bool "Enable separate DMA Contiguous M 178 bool "Enable separate DMA Contiguous Memory Area for NUMA Node"
179 depends on NUMA 179 depends on NUMA
180 help 180 help
181 Enable this option to get numa CMA a 181 Enable this option to get numa CMA areas so that NUMA devices
182 can get local memory by DMA coherent 182 can get local memory by DMA coherent APIs.
183 183
184 You can set the size of pernuma CMA 184 You can set the size of pernuma CMA by specifying "cma_pernuma=size"
185 or set the node id and its size of C 185 or set the node id and its size of CMA by specifying "numa_cma=
186 <node>:size[,<node>:size]" on the ke 186 <node>:size[,<node>:size]" on the kernel's command line.
187 187
188 comment "Default contiguous memory area size:" 188 comment "Default contiguous memory area size:"
189 189
190 config CMA_SIZE_MBYTES 190 config CMA_SIZE_MBYTES
191 int "Size in Mega Bytes" 191 int "Size in Mega Bytes"
192 depends on !CMA_SIZE_SEL_PERCENTAGE 192 depends on !CMA_SIZE_SEL_PERCENTAGE
193 default 0 if X86 193 default 0 if X86
194 default 16 194 default 16
195 help 195 help
196 Defines the size (in MiB) of the def 196 Defines the size (in MiB) of the default memory area for Contiguous
197 Memory Allocator. If the size of 0 197 Memory Allocator. If the size of 0 is selected, CMA is disabled by
198 default, but it can be enabled by pa 198 default, but it can be enabled by passing cma=size[MG] to the kernel.
199 199
200 200
201 config CMA_SIZE_PERCENTAGE 201 config CMA_SIZE_PERCENTAGE
202 int "Percentage of total memory" 202 int "Percentage of total memory"
203 depends on !CMA_SIZE_SEL_MBYTES 203 depends on !CMA_SIZE_SEL_MBYTES
204 default 0 if X86 204 default 0 if X86
205 default 10 205 default 10
206 help 206 help
207 Defines the size of the default memo 207 Defines the size of the default memory area for Contiguous Memory
208 Allocator as a percentage of the tot 208 Allocator as a percentage of the total memory in the system.
209 If 0 percent is selected, CMA is dis 209 If 0 percent is selected, CMA is disabled by default, but it can be
210 enabled by passing cma=size[MG] to t 210 enabled by passing cma=size[MG] to the kernel.
211 211
212 choice 212 choice
213 prompt "Selected region size" 213 prompt "Selected region size"
214 default CMA_SIZE_SEL_MBYTES 214 default CMA_SIZE_SEL_MBYTES
215 215
216 config CMA_SIZE_SEL_MBYTES 216 config CMA_SIZE_SEL_MBYTES
217 bool "Use mega bytes value only" 217 bool "Use mega bytes value only"
218 218
219 config CMA_SIZE_SEL_PERCENTAGE 219 config CMA_SIZE_SEL_PERCENTAGE
220 bool "Use percentage value only" 220 bool "Use percentage value only"
221 221
222 config CMA_SIZE_SEL_MIN 222 config CMA_SIZE_SEL_MIN
223 bool "Use lower value (minimum)" 223 bool "Use lower value (minimum)"
224 224
225 config CMA_SIZE_SEL_MAX 225 config CMA_SIZE_SEL_MAX
226 bool "Use higher value (maximum)" 226 bool "Use higher value (maximum)"
227 227
228 endchoice 228 endchoice
229 229
230 config CMA_ALIGNMENT 230 config CMA_ALIGNMENT
231 int "Maximum PAGE_SIZE order of alignm 231 int "Maximum PAGE_SIZE order of alignment for contiguous buffers"
232 range 2 12 232 range 2 12
233 default 8 233 default 8
234 help 234 help
235 DMA mapping framework by default ali 235 DMA mapping framework by default aligns all buffers to the smallest
236 PAGE_SIZE order which is greater tha 236 PAGE_SIZE order which is greater than or equal to the requested buffer
237 size. This works well for buffers up 237 size. This works well for buffers up to a few hundreds kilobytes, but
238 for larger buffers it just a memory 238 for larger buffers it just a memory waste. With this parameter you can
239 specify the maximum PAGE_SIZE order 239 specify the maximum PAGE_SIZE order for contiguous buffers. Larger
240 buffers will be aligned only to this 240 buffers will be aligned only to this specified order. The order is
241 expressed as a power of two multipli 241 expressed as a power of two multiplied by the PAGE_SIZE.
242 242
243 For example, if your system defaults 243 For example, if your system defaults to 4KiB pages, the order value
244 of 8 means that the buffers will be 244 of 8 means that the buffers will be aligned up to 1MiB only.
245 245
246 If unsure, leave the default value " 246 If unsure, leave the default value "8".
247 247
248 endif 248 endif
249 249
250 config DMA_API_DEBUG 250 config DMA_API_DEBUG
251 bool "Enable debugging of DMA-API usag 251 bool "Enable debugging of DMA-API usage"
252 select NEED_DMA_MAP_STATE 252 select NEED_DMA_MAP_STATE
253 help 253 help
254 Enable this option to debug the use 254 Enable this option to debug the use of the DMA API by device drivers.
255 With this option you will be able to 255 With this option you will be able to detect common bugs in device
256 drivers like double-freeing of DMA m 256 drivers like double-freeing of DMA mappings or freeing mappings that
257 were never allocated. 257 were never allocated.
258 258
259 This option causes a performance deg 259 This option causes a performance degradation. Use only if you want to
260 debug device drivers and dma interac 260 debug device drivers and dma interactions.
261 261
262 If unsure, say N. 262 If unsure, say N.
263 263
264 config DMA_API_DEBUG_SG 264 config DMA_API_DEBUG_SG
265 bool "Debug DMA scatter-gather usage" 265 bool "Debug DMA scatter-gather usage"
266 default y 266 default y
267 depends on DMA_API_DEBUG 267 depends on DMA_API_DEBUG
268 help 268 help
269 Perform extra checking that callers 269 Perform extra checking that callers of dma_map_sg() have respected the
270 appropriate segment length/boundary 270 appropriate segment length/boundary limits for the given device when
271 preparing DMA scatterlists. 271 preparing DMA scatterlists.
272 272
273 This is particularly likely to have 273 This is particularly likely to have been overlooked in cases where the
274 dma_map_sg() API is used for general 274 dma_map_sg() API is used for general bulk mapping of pages rather than
275 preparing literal scatter-gather des 275 preparing literal scatter-gather descriptors, where there is a risk of
276 unexpected behaviour from DMA API im 276 unexpected behaviour from DMA API implementations if the scatterlist
277 is technically out-of-spec. 277 is technically out-of-spec.
278 278
279 If unsure, say N. 279 If unsure, say N.
280 280
281 config DMA_MAP_BENCHMARK 281 config DMA_MAP_BENCHMARK
282 bool "Enable benchmarking of streaming 282 bool "Enable benchmarking of streaming DMA mapping"
283 depends on DEBUG_FS 283 depends on DEBUG_FS
284 help 284 help
285 Provides /sys/kernel/debug/dma_map_b 285 Provides /sys/kernel/debug/dma_map_benchmark that helps with testing
286 performance of dma_(un)map_page. 286 performance of dma_(un)map_page.
287 287
288 See tools/testing/selftests/dma/dma_ 288 See tools/testing/selftests/dma/dma_map_benchmark.c
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