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