xref: /linux/kernel/dma/Kconfig (revision 4d3af20eaf3fcd481a797738bb46634e37f4a1cc)
1ec8f24b7SThomas Gleixner# SPDX-License-Identifier: GPL-2.0-only
2cf65a0f6SChristoph Hellwig
3846f9e1fSChristoph Hellwigconfig NO_DMA
4846f9e1fSChristoph Hellwig	bool
5846f9e1fSChristoph Hellwig
6cf65a0f6SChristoph Hellwigconfig HAS_DMA
7cf65a0f6SChristoph Hellwig	bool
8cf65a0f6SChristoph Hellwig	depends on !NO_DMA
9cf65a0f6SChristoph Hellwig	default y
10cf65a0f6SChristoph Hellwig
112f9237d4SChristoph Hellwigconfig DMA_OPS
12ef1a85b6SChristoph Hellwig	depends on HAS_DMA
132f9237d4SChristoph Hellwig	bool
142f9237d4SChristoph Hellwig
15d35834c6SChristoph Hellwig#
16d35834c6SChristoph Hellwig# IOMMU drivers that can bypass the IOMMU code and optionally use the direct
17d35834c6SChristoph Hellwig# mapping fast path should select this option and set the dma_ops_bypass
18d35834c6SChristoph Hellwig# flag in struct device where applicable
19d35834c6SChristoph Hellwig#
20d35834c6SChristoph Hellwigconfig DMA_OPS_BYPASS
21d35834c6SChristoph Hellwig	bool
22d35834c6SChristoph Hellwig
238d8d53cfSAlexey Kardashevskiy# Lets platform IOMMU driver choose between bypass and IOMMU
248d8d53cfSAlexey Kardashevskiyconfig ARCH_HAS_DMA_MAP_DIRECT
258d8d53cfSAlexey Kardashevskiy	bool
268d8d53cfSAlexey Kardashevskiy
27cf65a0f6SChristoph Hellwigconfig NEED_SG_DMA_LENGTH
28cf65a0f6SChristoph Hellwig	bool
29cf65a0f6SChristoph Hellwig
30cf65a0f6SChristoph Hellwigconfig NEED_DMA_MAP_STATE
31cf65a0f6SChristoph Hellwig	bool
32cf65a0f6SChristoph Hellwig
33cf65a0f6SChristoph Hellwigconfig ARCH_DMA_ADDR_T_64BIT
34cf65a0f6SChristoph Hellwig	def_bool 64BIT || PHYS_ADDR_T_64BIT
35cf65a0f6SChristoph Hellwig
3611ddce15SChristoph Hellwigconfig ARCH_HAS_DMA_SET_MASK
3711ddce15SChristoph Hellwig	bool
3811ddce15SChristoph Hellwig
39419e2f18SChristoph Hellwig#
40419e2f18SChristoph Hellwig# Select this option if the architecture needs special handling for
41419e2f18SChristoph Hellwig# DMA_ATTR_WRITE_COMBINE.  Normally the "uncached" mapping should be what
42*4d3af20eSSui Jingfeng# people think of when saying write combine, so very few platforms should
43419e2f18SChristoph Hellwig# need to enable this.
44419e2f18SChristoph Hellwig#
45419e2f18SChristoph Hellwigconfig ARCH_HAS_DMA_WRITE_COMBINE
46419e2f18SChristoph Hellwig	bool
47419e2f18SChristoph Hellwig
48abdaf11aSChristoph Hellwig#
49abdaf11aSChristoph Hellwig# Select if the architectures provides the arch_dma_mark_clean hook
50abdaf11aSChristoph Hellwig#
51abdaf11aSChristoph Hellwigconfig ARCH_HAS_DMA_MARK_CLEAN
52abdaf11aSChristoph Hellwig	bool
53abdaf11aSChristoph Hellwig
54ff4c25f2SChristoph Hellwigconfig DMA_DECLARE_COHERENT
55cf65a0f6SChristoph Hellwig	bool
56cf65a0f6SChristoph Hellwig
57347cb6afSChristoph Hellwigconfig ARCH_HAS_SETUP_DMA_OPS
58347cb6afSChristoph Hellwig	bool
59347cb6afSChristoph Hellwig
60dc2acdedSChristoph Hellwigconfig ARCH_HAS_TEARDOWN_DMA_OPS
61cf65a0f6SChristoph Hellwig	bool
62cf65a0f6SChristoph Hellwig
63cf65a0f6SChristoph Hellwigconfig ARCH_HAS_SYNC_DMA_FOR_DEVICE
64cf65a0f6SChristoph Hellwig	bool
65cf65a0f6SChristoph Hellwig
66cf65a0f6SChristoph Hellwigconfig ARCH_HAS_SYNC_DMA_FOR_CPU
67cf65a0f6SChristoph Hellwig	bool
68cf65a0f6SChristoph Hellwig	select NEED_DMA_MAP_STATE
69cf65a0f6SChristoph Hellwig
70684f7e91SChristoph Hellwigconfig ARCH_HAS_SYNC_DMA_FOR_CPU_ALL
71684f7e91SChristoph Hellwig	bool
72684f7e91SChristoph Hellwig
7313bf5cedSChristoph Hellwigconfig ARCH_HAS_DMA_PREP_COHERENT
7413bf5cedSChristoph Hellwig	bool
7513bf5cedSChristoph Hellwig
769087c375STom Lendackyconfig ARCH_HAS_FORCE_DMA_UNENCRYPTED
779087c375STom Lendacky	bool
789087c375STom Lendacky
791d3f56b2SJiaxun Yang#
801d3f56b2SJiaxun Yang# Select this option if the architecture assumes DMA devices are coherent
811d3f56b2SJiaxun Yang# by default.
821d3f56b2SJiaxun Yang#
831d3f56b2SJiaxun Yangconfig ARCH_DMA_DEFAULT_COHERENT
841d3f56b2SJiaxun Yang	bool
851d3f56b2SJiaxun Yang
86cf65a0f6SChristoph Hellwigconfig SWIOTLB
87cf65a0f6SChristoph Hellwig	bool
88cf65a0f6SChristoph Hellwig	select NEED_DMA_MAP_STATE
89f0edfea8SChristoph Hellwig
900b84e4f8SClaire Changconfig DMA_RESTRICTED_POOL
910b84e4f8SClaire Chang	bool "DMA Restricted Pool"
92f3c4b134SClaire Chang	depends on OF && OF_RESERVED_MEM && SWIOTLB
930b84e4f8SClaire Chang	help
940b84e4f8SClaire Chang	  This enables support for restricted DMA pools which provide a level of
950b84e4f8SClaire Chang	  DMA memory protection on systems with limited hardware protection
960b84e4f8SClaire Chang	  capabilities, such as those lacking an IOMMU.
970b84e4f8SClaire Chang
980b84e4f8SClaire Chang	  For more information see
990b84e4f8SClaire Chang	  <Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt>
1000b84e4f8SClaire Chang	  and <kernel/dma/swiotlb.c>.
1010b84e4f8SClaire Chang	  If unsure, say "n".
1020b84e4f8SClaire Chang
10334dc0ea6SChristoph Hellwig#
10434dc0ea6SChristoph Hellwig# Should be selected if we can mmap non-coherent mappings to userspace.
10534dc0ea6SChristoph Hellwig# The only thing that is really required is a way to set an uncached bit
10634dc0ea6SChristoph Hellwig# in the pagetables
10734dc0ea6SChristoph Hellwig#
10834dc0ea6SChristoph Hellwigconfig DMA_NONCOHERENT_MMAP
1091fbf57d0SChristoph Hellwig	default y if !MMU
11034dc0ea6SChristoph Hellwig	bool
11134dc0ea6SChristoph Hellwig
112dbed452aSDavid Rientjesconfig DMA_COHERENT_POOL
113d07ae4c4SChristoph Hellwig	select GENERIC_ALLOCATOR
114dbed452aSDavid Rientjes	bool
115dbed452aSDavid Rientjes
116faf4ef82SChristoph Hellwigconfig DMA_GLOBAL_POOL
117faf4ef82SChristoph Hellwig	select DMA_DECLARE_COHERENT
118faf4ef82SChristoph Hellwig	bool
119faf4ef82SChristoph Hellwig
120e860c299SDavid Rientjesconfig DMA_DIRECT_REMAP
121e860c299SDavid Rientjes	bool
122e860c299SDavid Rientjes	select DMA_COHERENT_POOL
123f5ff79fdSChristoph Hellwig	select DMA_NONCOHERENT_MMAP
124e860c299SDavid Rientjes
125ddb26d8eSChristoph Hellwigconfig DMA_CMA
126ddb26d8eSChristoph Hellwig	bool "DMA Contiguous Memory Allocator"
127ddb26d8eSChristoph Hellwig	depends on HAVE_DMA_CONTIGUOUS && CMA
128ddb26d8eSChristoph Hellwig	help
129ddb26d8eSChristoph Hellwig	  This enables the Contiguous Memory Allocator which allows drivers
130ddb26d8eSChristoph Hellwig	  to allocate big physically-contiguous blocks of memory for use with
131ddb26d8eSChristoph Hellwig	  hardware components that do not support I/O map nor scatter-gather.
132ddb26d8eSChristoph Hellwig
133ddb26d8eSChristoph Hellwig	  You can disable CMA by specifying "cma=0" on the kernel's command
134ddb26d8eSChristoph Hellwig	  line.
135ddb26d8eSChristoph Hellwig
1360b1abd1fSChristoph Hellwig	  For more information see <kernel/dma/contiguous.c>.
137ddb26d8eSChristoph Hellwig	  If unsure, say "n".
138ddb26d8eSChristoph Hellwig
139ddb26d8eSChristoph Hellwigif  DMA_CMA
140b7176c26SBarry Song
141b7176c26SBarry Songconfig DMA_PERNUMA_CMA
142b7176c26SBarry Song	bool "Enable separate DMA Contiguous Memory Area for each NUMA Node"
143b7176c26SBarry Song	default NUMA && ARM64
144b7176c26SBarry Song	help
145b7176c26SBarry Song	  Enable this option to get pernuma CMA areas so that devices like
146b7176c26SBarry Song	  ARM64 SMMU can get local memory by DMA coherent APIs.
147b7176c26SBarry Song
148b7176c26SBarry Song	  You can set the size of pernuma CMA by specifying "cma_pernuma=size"
149b7176c26SBarry Song	  on the kernel's command line.
150b7176c26SBarry Song
151ddb26d8eSChristoph Hellwigcomment "Default contiguous memory area size:"
152ddb26d8eSChristoph Hellwig
153ddb26d8eSChristoph Hellwigconfig CMA_SIZE_MBYTES
154ddb26d8eSChristoph Hellwig	int "Size in Mega Bytes"
155ddb26d8eSChristoph Hellwig	depends on !CMA_SIZE_SEL_PERCENTAGE
156ddb26d8eSChristoph Hellwig	default 0 if X86
157ddb26d8eSChristoph Hellwig	default 16
158ddb26d8eSChristoph Hellwig	help
159ddb26d8eSChristoph Hellwig	  Defines the size (in MiB) of the default memory area for Contiguous
160ddb26d8eSChristoph Hellwig	  Memory Allocator.  If the size of 0 is selected, CMA is disabled by
161ddb26d8eSChristoph Hellwig	  default, but it can be enabled by passing cma=size[MG] to the kernel.
162ddb26d8eSChristoph Hellwig
163ddb26d8eSChristoph Hellwig
164ddb26d8eSChristoph Hellwigconfig CMA_SIZE_PERCENTAGE
165ddb26d8eSChristoph Hellwig	int "Percentage of total memory"
166ddb26d8eSChristoph Hellwig	depends on !CMA_SIZE_SEL_MBYTES
167ddb26d8eSChristoph Hellwig	default 0 if X86
168ddb26d8eSChristoph Hellwig	default 10
169ddb26d8eSChristoph Hellwig	help
170ddb26d8eSChristoph Hellwig	  Defines the size of the default memory area for Contiguous Memory
171ddb26d8eSChristoph Hellwig	  Allocator as a percentage of the total memory in the system.
172ddb26d8eSChristoph Hellwig	  If 0 percent is selected, CMA is disabled by default, but it can be
173ddb26d8eSChristoph Hellwig	  enabled by passing cma=size[MG] to the kernel.
174ddb26d8eSChristoph Hellwig
175ddb26d8eSChristoph Hellwigchoice
176ddb26d8eSChristoph Hellwig	prompt "Selected region size"
177ddb26d8eSChristoph Hellwig	default CMA_SIZE_SEL_MBYTES
178ddb26d8eSChristoph Hellwig
179ddb26d8eSChristoph Hellwigconfig CMA_SIZE_SEL_MBYTES
180ddb26d8eSChristoph Hellwig	bool "Use mega bytes value only"
181ddb26d8eSChristoph Hellwig
182ddb26d8eSChristoph Hellwigconfig CMA_SIZE_SEL_PERCENTAGE
183ddb26d8eSChristoph Hellwig	bool "Use percentage value only"
184ddb26d8eSChristoph Hellwig
185ddb26d8eSChristoph Hellwigconfig CMA_SIZE_SEL_MIN
186ddb26d8eSChristoph Hellwig	bool "Use lower value (minimum)"
187ddb26d8eSChristoph Hellwig
188ddb26d8eSChristoph Hellwigconfig CMA_SIZE_SEL_MAX
189ddb26d8eSChristoph Hellwig	bool "Use higher value (maximum)"
190ddb26d8eSChristoph Hellwig
191ddb26d8eSChristoph Hellwigendchoice
192ddb26d8eSChristoph Hellwig
193ddb26d8eSChristoph Hellwigconfig CMA_ALIGNMENT
194ddb26d8eSChristoph Hellwig	int "Maximum PAGE_SIZE order of alignment for contiguous buffers"
1950de32796SPaul Cercueil	range 2 12
196ddb26d8eSChristoph Hellwig	default 8
197ddb26d8eSChristoph Hellwig	help
198ddb26d8eSChristoph Hellwig	  DMA mapping framework by default aligns all buffers to the smallest
199ddb26d8eSChristoph Hellwig	  PAGE_SIZE order which is greater than or equal to the requested buffer
200ddb26d8eSChristoph Hellwig	  size. This works well for buffers up to a few hundreds kilobytes, but
201ddb26d8eSChristoph Hellwig	  for larger buffers it just a memory waste. With this parameter you can
202ddb26d8eSChristoph Hellwig	  specify the maximum PAGE_SIZE order for contiguous buffers. Larger
203ddb26d8eSChristoph Hellwig	  buffers will be aligned only to this specified order. The order is
204ddb26d8eSChristoph Hellwig	  expressed as a power of two multiplied by the PAGE_SIZE.
205ddb26d8eSChristoph Hellwig
206ddb26d8eSChristoph Hellwig	  For example, if your system defaults to 4KiB pages, the order value
207ddb26d8eSChristoph Hellwig	  of 8 means that the buffers will be aligned up to 1MiB only.
208ddb26d8eSChristoph Hellwig
209ddb26d8eSChristoph Hellwig	  If unsure, leave the default value "8".
210ddb26d8eSChristoph Hellwig
211ddb26d8eSChristoph Hellwigendif
212ddb26d8eSChristoph Hellwig
21370ca7ba2SAndy Shevchenkoconfig DMA_API_DEBUG
21470ca7ba2SAndy Shevchenko	bool "Enable debugging of DMA-API usage"
21570ca7ba2SAndy Shevchenko	select NEED_DMA_MAP_STATE
21670ca7ba2SAndy Shevchenko	help
21770ca7ba2SAndy Shevchenko	  Enable this option to debug the use of the DMA API by device drivers.
21870ca7ba2SAndy Shevchenko	  With this option you will be able to detect common bugs in device
21970ca7ba2SAndy Shevchenko	  drivers like double-freeing of DMA mappings or freeing mappings that
22070ca7ba2SAndy Shevchenko	  were never allocated.
22170ca7ba2SAndy Shevchenko
22270ca7ba2SAndy Shevchenko	  This option causes a performance degradation.  Use only if you want to
22370ca7ba2SAndy Shevchenko	  debug device drivers and dma interactions.
22470ca7ba2SAndy Shevchenko
22570ca7ba2SAndy Shevchenko	  If unsure, say N.
22670ca7ba2SAndy Shevchenko
22770ca7ba2SAndy Shevchenkoconfig DMA_API_DEBUG_SG
22870ca7ba2SAndy Shevchenko	bool "Debug DMA scatter-gather usage"
22970ca7ba2SAndy Shevchenko	default y
23070ca7ba2SAndy Shevchenko	depends on DMA_API_DEBUG
23170ca7ba2SAndy Shevchenko	help
23270ca7ba2SAndy Shevchenko	  Perform extra checking that callers of dma_map_sg() have respected the
23370ca7ba2SAndy Shevchenko	  appropriate segment length/boundary limits for the given device when
23470ca7ba2SAndy Shevchenko	  preparing DMA scatterlists.
23570ca7ba2SAndy Shevchenko
23670ca7ba2SAndy Shevchenko	  This is particularly likely to have been overlooked in cases where the
23770ca7ba2SAndy Shevchenko	  dma_map_sg() API is used for general bulk mapping of pages rather than
23870ca7ba2SAndy Shevchenko	  preparing literal scatter-gather descriptors, where there is a risk of
23970ca7ba2SAndy Shevchenko	  unexpected behaviour from DMA API implementations if the scatterlist
24070ca7ba2SAndy Shevchenko	  is technically out-of-spec.
24170ca7ba2SAndy Shevchenko
24270ca7ba2SAndy Shevchenko	  If unsure, say N.
24365789daaSBarry Song
24465789daaSBarry Songconfig DMA_MAP_BENCHMARK
24565789daaSBarry Song	bool "Enable benchmarking of streaming DMA mapping"
24665789daaSBarry Song	depends on DEBUG_FS
24765789daaSBarry Song	help
24865789daaSBarry Song	  Provides /sys/kernel/debug/dma_map_benchmark that helps with testing
24965789daaSBarry Song	  performance of dma_(un)map_page.
25065789daaSBarry Song
25165789daaSBarry Song	  See tools/testing/selftests/dma/dma_map_benchmark.c
252