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 def_bool ARCH_HAS_SYNC_DMA_FOR_DEVICE <<
111 ARCH_HAS_SYNC_DMA_FOR_CPU_ALL <<
112 ARCH_HAS_DMA_OPS || SWIOTLB <<
113 <<
114 config DMA_RESTRICTED_POOL 110 config DMA_RESTRICTED_POOL
115 bool "DMA Restricted Pool" 111 bool "DMA Restricted Pool"
116 depends on OF && OF_RESERVED_MEM && SW 112 depends on OF && OF_RESERVED_MEM && SWIOTLB
117 help 113 help
118 This enables support for restricted 114 This enables support for restricted DMA pools which provide a level of
119 DMA memory protection on systems wit 115 DMA memory protection on systems with limited hardware protection
120 capabilities, such as those lacking 116 capabilities, such as those lacking an IOMMU.
121 117
122 For more information see 118 For more information see
123 <Documentation/devicetree/bindings/r 119 <Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt>
124 and <kernel/dma/swiotlb.c>. 120 and <kernel/dma/swiotlb.c>.
125 If unsure, say "n". 121 If unsure, say "n".
126 122
127 # 123 #
128 # Should be selected if we can mmap non-cohere 124 # Should be selected if we can mmap non-coherent mappings to userspace.
129 # The only thing that is really required is a 125 # The only thing that is really required is a way to set an uncached bit
130 # in the pagetables 126 # in the pagetables
131 # 127 #
132 config DMA_NONCOHERENT_MMAP 128 config DMA_NONCOHERENT_MMAP
133 default y if !MMU 129 default y if !MMU
134 bool 130 bool
135 131
136 config DMA_COHERENT_POOL 132 config DMA_COHERENT_POOL
137 select GENERIC_ALLOCATOR 133 select GENERIC_ALLOCATOR
138 bool 134 bool
139 135
140 config DMA_GLOBAL_POOL 136 config DMA_GLOBAL_POOL
141 select DMA_DECLARE_COHERENT 137 select DMA_DECLARE_COHERENT
142 depends on !ARCH_HAS_DMA_SET_UNCACHED <<
143 depends on !DMA_DIRECT_REMAP <<
144 bool 138 bool
145 139
146 config DMA_DIRECT_REMAP 140 config DMA_DIRECT_REMAP
147 bool 141 bool
148 select DMA_COHERENT_POOL 142 select DMA_COHERENT_POOL
149 select DMA_NONCOHERENT_MMAP 143 select DMA_NONCOHERENT_MMAP
150 <<
151 # <<
152 # Fallback to arch code for DMA allocations. <<
153 # <<
154 config ARCH_HAS_DMA_ALLOC <<
155 depends on !ARCH_HAS_DMA_SET_UNCACHED <<
156 depends on !DMA_DIRECT_REMAP <<
157 depends on !DMA_GLOBAL_POOL <<
158 bool <<
159 144
160 config DMA_CMA 145 config DMA_CMA
161 bool "DMA Contiguous Memory Allocator" 146 bool "DMA Contiguous Memory Allocator"
162 depends on HAVE_DMA_CONTIGUOUS && CMA 147 depends on HAVE_DMA_CONTIGUOUS && CMA
163 help 148 help
164 This enables the Contiguous Memory A 149 This enables the Contiguous Memory Allocator which allows drivers
165 to allocate big physically-contiguou 150 to allocate big physically-contiguous blocks of memory for use with
166 hardware components that do not supp 151 hardware components that do not support I/O map nor scatter-gather.
167 152
168 You can disable CMA by specifying "c 153 You can disable CMA by specifying "cma=0" on the kernel's command
169 line. 154 line.
170 155
171 For more information see <kernel/dma 156 For more information see <kernel/dma/contiguous.c>.
172 If unsure, say "n". 157 If unsure, say "n".
173 158
174 if DMA_CMA 159 if DMA_CMA
175 160
176 config DMA_NUMA_CMA 161 config DMA_NUMA_CMA
177 bool "Enable separate DMA Contiguous M 162 bool "Enable separate DMA Contiguous Memory Area for NUMA Node"
178 depends on NUMA 163 depends on NUMA
179 help 164 help
180 Enable this option to get numa CMA a 165 Enable this option to get numa CMA areas so that NUMA devices
181 can get local memory by DMA coherent 166 can get local memory by DMA coherent APIs.
182 167
183 You can set the size of pernuma CMA 168 You can set the size of pernuma CMA by specifying "cma_pernuma=size"
184 or set the node id and its size of C 169 or set the node id and its size of CMA by specifying "numa_cma=
185 <node>:size[,<node>:size]" on the ke 170 <node>:size[,<node>:size]" on the kernel's command line.
186 171
187 comment "Default contiguous memory area size:" 172 comment "Default contiguous memory area size:"
188 173
189 config CMA_SIZE_MBYTES 174 config CMA_SIZE_MBYTES
190 int "Size in Mega Bytes" 175 int "Size in Mega Bytes"
191 depends on !CMA_SIZE_SEL_PERCENTAGE 176 depends on !CMA_SIZE_SEL_PERCENTAGE
192 default 0 if X86 177 default 0 if X86
193 default 16 178 default 16
194 help 179 help
195 Defines the size (in MiB) of the def 180 Defines the size (in MiB) of the default memory area for Contiguous
196 Memory Allocator. If the size of 0 181 Memory Allocator. If the size of 0 is selected, CMA is disabled by
197 default, but it can be enabled by pa 182 default, but it can be enabled by passing cma=size[MG] to the kernel.
198 183
199 184
200 config CMA_SIZE_PERCENTAGE 185 config CMA_SIZE_PERCENTAGE
201 int "Percentage of total memory" 186 int "Percentage of total memory"
202 depends on !CMA_SIZE_SEL_MBYTES 187 depends on !CMA_SIZE_SEL_MBYTES
203 default 0 if X86 188 default 0 if X86
204 default 10 189 default 10
205 help 190 help
206 Defines the size of the default memo 191 Defines the size of the default memory area for Contiguous Memory
207 Allocator as a percentage of the tot 192 Allocator as a percentage of the total memory in the system.
208 If 0 percent is selected, CMA is dis 193 If 0 percent is selected, CMA is disabled by default, but it can be
209 enabled by passing cma=size[MG] to t 194 enabled by passing cma=size[MG] to the kernel.
210 195
211 choice 196 choice
212 prompt "Selected region size" 197 prompt "Selected region size"
213 default CMA_SIZE_SEL_MBYTES 198 default CMA_SIZE_SEL_MBYTES
214 199
215 config CMA_SIZE_SEL_MBYTES 200 config CMA_SIZE_SEL_MBYTES
216 bool "Use mega bytes value only" 201 bool "Use mega bytes value only"
217 202
218 config CMA_SIZE_SEL_PERCENTAGE 203 config CMA_SIZE_SEL_PERCENTAGE
219 bool "Use percentage value only" 204 bool "Use percentage value only"
220 205
221 config CMA_SIZE_SEL_MIN 206 config CMA_SIZE_SEL_MIN
222 bool "Use lower value (minimum)" 207 bool "Use lower value (minimum)"
223 208
224 config CMA_SIZE_SEL_MAX 209 config CMA_SIZE_SEL_MAX
225 bool "Use higher value (maximum)" 210 bool "Use higher value (maximum)"
226 211
227 endchoice 212 endchoice
228 213
229 config CMA_ALIGNMENT 214 config CMA_ALIGNMENT
230 int "Maximum PAGE_SIZE order of alignm 215 int "Maximum PAGE_SIZE order of alignment for contiguous buffers"
231 range 2 12 216 range 2 12
232 default 8 217 default 8
233 help 218 help
234 DMA mapping framework by default ali 219 DMA mapping framework by default aligns all buffers to the smallest
235 PAGE_SIZE order which is greater tha 220 PAGE_SIZE order which is greater than or equal to the requested buffer
236 size. This works well for buffers up 221 size. This works well for buffers up to a few hundreds kilobytes, but
237 for larger buffers it just a memory 222 for larger buffers it just a memory waste. With this parameter you can
238 specify the maximum PAGE_SIZE order 223 specify the maximum PAGE_SIZE order for contiguous buffers. Larger
239 buffers will be aligned only to this 224 buffers will be aligned only to this specified order. The order is
240 expressed as a power of two multipli 225 expressed as a power of two multiplied by the PAGE_SIZE.
241 226
242 For example, if your system defaults 227 For example, if your system defaults to 4KiB pages, the order value
243 of 8 means that the buffers will be 228 of 8 means that the buffers will be aligned up to 1MiB only.
244 229
245 If unsure, leave the default value " 230 If unsure, leave the default value "8".
246 231
247 endif 232 endif
248 233
249 config DMA_API_DEBUG 234 config DMA_API_DEBUG
250 bool "Enable debugging of DMA-API usag 235 bool "Enable debugging of DMA-API usage"
251 select NEED_DMA_MAP_STATE 236 select NEED_DMA_MAP_STATE
252 help 237 help
253 Enable this option to debug the use 238 Enable this option to debug the use of the DMA API by device drivers.
254 With this option you will be able to 239 With this option you will be able to detect common bugs in device
255 drivers like double-freeing of DMA m 240 drivers like double-freeing of DMA mappings or freeing mappings that
256 were never allocated. 241 were never allocated.
257 242
258 This option causes a performance deg 243 This option causes a performance degradation. Use only if you want to
259 debug device drivers and dma interac 244 debug device drivers and dma interactions.
260 245
261 If unsure, say N. 246 If unsure, say N.
262 247
263 config DMA_API_DEBUG_SG 248 config DMA_API_DEBUG_SG
264 bool "Debug DMA scatter-gather usage" 249 bool "Debug DMA scatter-gather usage"
265 default y 250 default y
266 depends on DMA_API_DEBUG 251 depends on DMA_API_DEBUG
267 help 252 help
268 Perform extra checking that callers 253 Perform extra checking that callers of dma_map_sg() have respected the
269 appropriate segment length/boundary 254 appropriate segment length/boundary limits for the given device when
270 preparing DMA scatterlists. 255 preparing DMA scatterlists.
271 256
272 This is particularly likely to have 257 This is particularly likely to have been overlooked in cases where the
273 dma_map_sg() API is used for general 258 dma_map_sg() API is used for general bulk mapping of pages rather than
274 preparing literal scatter-gather des 259 preparing literal scatter-gather descriptors, where there is a risk of
275 unexpected behaviour from DMA API im 260 unexpected behaviour from DMA API implementations if the scatterlist
276 is technically out-of-spec. 261 is technically out-of-spec.
277 262
278 If unsure, say N. 263 If unsure, say N.
279 264
280 config DMA_MAP_BENCHMARK 265 config DMA_MAP_BENCHMARK
281 bool "Enable benchmarking of streaming 266 bool "Enable benchmarking of streaming DMA mapping"
282 depends on DEBUG_FS 267 depends on DEBUG_FS
283 help 268 help
284 Provides /sys/kernel/debug/dma_map_b 269 Provides /sys/kernel/debug/dma_map_benchmark that helps with testing
285 performance of dma_(un)map_page. 270 performance of dma_(un)map_page.
286 271
287 See tools/testing/selftests/dma/dma_ 272 See tools/testing/selftests/dma/dma_map_benchmark.c
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