1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __IO_PGTABLE_H
3 #define __IO_PGTABLE_H
4
5 #include <linux/bitops.h>
6 #include <linux/iommu.h>
7
8 /*
9 * Public API for use by IOMMU drivers
10 */
11 enum io_pgtable_fmt {
12 ARM_32_LPAE_S1,
13 ARM_32_LPAE_S2,
14 ARM_64_LPAE_S1,
15 ARM_64_LPAE_S2,
16 ARM_V7S,
17 ARM_MALI_LPAE,
18 IO_PGTABLE_NUM_FMTS,
19 };
20
21 /**
22 * struct iommu_flush_ops - IOMMU callbacks for TLB and page table management.
23 *
24 * @tlb_flush_all: Synchronously invalidate the entire TLB context.
25 * @tlb_flush_walk: Synchronously invalidate all intermediate TLB state
26 * (sometimes referred to as the "walk cache") for a virtual
27 * address range.
28 * @tlb_flush_leaf: Synchronously invalidate all leaf TLB state for a virtual
29 * address range.
30 * @tlb_add_page: Optional callback to queue up leaf TLB invalidation for a
31 * single page. IOMMUs that cannot batch TLB invalidation
32 * operations efficiently will typically issue them here, but
33 * others may decide to update the iommu_iotlb_gather structure
34 * and defer the invalidation until iommu_tlb_sync() instead.
35 *
36 * Note that these can all be called in atomic context and must therefore
37 * not block.
38 */
39 struct iommu_flush_ops {
40 void (*tlb_flush_all)(void *cookie);
41 void (*tlb_flush_walk)(unsigned long iova, size_t size, size_t granule,
42 void *cookie);
43 void (*tlb_flush_leaf)(unsigned long iova, size_t size, size_t granule,
44 void *cookie);
45 void (*tlb_add_page)(struct iommu_iotlb_gather *gather,
46 unsigned long iova, size_t granule, void *cookie);
47 };
48
49 /**
50 * struct iommu_pgtable_ops - IOMMU callbacks for page table memory management.
51 *
52 * @alloc_pgtable: Allocate page table memory, and return a page-aligned
53 * cacheable linear mapping address of the start of a physically
54 * contiguous region of memory.
55 * @free_pgtable: Free page table memory.
56 */
57 struct iommu_pgtable_ops {
58 void *(*alloc_pgtable)(void *cookie, int order, gfp_t gfp_mask);
59 void (*free_pgtable)(void *cookie, void *virt, int order);
60 };
61
62 /**
63 * struct io_pgtable_cfg - Configuration data for a set of page tables.
64 *
65 * @quirks: A bitmap of hardware quirks that require some special
66 * action by the low-level page table allocator.
67 * @pgsize_bitmap: A bitmap of page sizes supported by this set of page
68 * tables.
69 * @ias: Input address (iova) size, in bits.
70 * @oas: Output address (paddr) size, in bits.
71 * @coherent_walk A flag to indicate whether or not page table walks made
72 * by the IOMMU are coherent with the CPU caches.
73 * @tlb: TLB management callbacks for this set of tables.
74 * @iommu_pgtable_ops: IOMMU page table memory management callbacks (optional;
75 * defaults to the buddy allocator if not present).
76 * @iommu_dev: The device representing the DMA configuration for the
77 * page table walker.
78 */
79 struct io_pgtable_cfg {
80 /*
81 * IO_PGTABLE_QUIRK_ARM_NS: (ARM formats) Set NS and NSTABLE bits in
82 * stage 1 PTEs, for hardware which insists on validating them
83 * even in non-secure state where they should normally be ignored.
84 *
85 * IO_PGTABLE_QUIRK_NO_PERMS: Ignore the IOMMU_READ, IOMMU_WRITE and
86 * IOMMU_NOEXEC flags and map everything with full access, for
87 * hardware which does not implement the permissions of a given
88 * format, and/or requires some format-specific default value.
89 *
90 * IO_PGTABLE_QUIRK_TLBI_ON_MAP: If the format forbids caching invalid
91 * (unmapped) entries but the hardware might do so anyway, perform
92 * TLB maintenance when mapping as well as when unmapping.
93 *
94 * IO_PGTABLE_QUIRK_ARM_MTK_EXT: (ARM v7s format) MediaTek IOMMUs extend
95 * to support up to 35 bits PA where the bit32, bit33 and bit34 are
96 * encoded in the bit9, bit4 and bit5 of the PTE respectively.
97 *
98 * IO_PGTABLE_QUIRK_NON_STRICT: Skip issuing synchronous leaf TLBIs
99 * on unmap, for DMA domains using the flush queue mechanism for
100 * delayed invalidation.
101 */
102 #define IO_PGTABLE_QUIRK_ARM_NS BIT(0)
103 #define IO_PGTABLE_QUIRK_NO_PERMS BIT(1)
104 #define IO_PGTABLE_QUIRK_TLBI_ON_MAP BIT(2)
105 #define IO_PGTABLE_QUIRK_ARM_MTK_EXT BIT(3)
106 #define IO_PGTABLE_QUIRK_NON_STRICT BIT(4)
107 unsigned long quirks;
108 unsigned long pgsize_bitmap;
109 unsigned int ias;
110 unsigned int oas;
111 bool coherent_walk;
112 const struct iommu_flush_ops *tlb;
113 const struct iommu_pgtable_ops *iommu_pgtable_ops;
114 struct device *iommu_dev;
115
116 /* Low-level data specific to the table format */
117 union {
118 struct {
119 u64 ttbr[2];
120 u64 tcr;
121 u64 mair[2];
122 } arm_lpae_s1_cfg;
123
124 struct {
125 u64 vttbr;
126 u64 vtcr;
127 } arm_lpae_s2_cfg;
128
129 struct {
130 u32 ttbr[2];
131 u32 tcr;
132 u32 nmrr;
133 u32 prrr;
134 } arm_v7s_cfg;
135
136 struct {
137 u64 transtab;
138 u64 memattr;
139 } arm_mali_lpae_cfg;
140 };
141 };
142
143 /**
144 * struct io_pgtable_ops - Page table manipulation API for IOMMU drivers.
145 *
146 * @map: Map a physically contiguous memory region.
147 * @unmap: Unmap a physically contiguous memory region.
148 * @iova_to_phys: Translate iova to physical address.
149 *
150 * These functions map directly onto the iommu_ops member functions with
151 * the same names.
152 */
153 struct io_pgtable_ops {
154 int (*map)(struct io_pgtable_ops *ops, unsigned long iova,
155 phys_addr_t paddr, size_t size, int prot);
156 size_t (*unmap)(struct io_pgtable_ops *ops, unsigned long iova,
157 size_t size, struct iommu_iotlb_gather *gather);
158 phys_addr_t (*iova_to_phys)(struct io_pgtable_ops *ops,
159 unsigned long iova);
160 };
161
162 /**
163 * alloc_io_pgtable_ops() - Allocate a page table allocator for use by an IOMMU.
164 *
165 * @fmt: The page table format.
166 * @cfg: The page table configuration. This will be modified to represent
167 * the configuration actually provided by the allocator (e.g. the
168 * pgsize_bitmap may be restricted).
169 * @cookie: An opaque token provided by the IOMMU driver and passed back to
170 * the callback routines in cfg->tlb.
171 */
172 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
173 struct io_pgtable_cfg *cfg,
174 void *cookie);
175
176 /**
177 * free_io_pgtable_ops() - Free an io_pgtable_ops structure. The caller
178 * *must* ensure that the page table is no longer
179 * live, but the TLB can be dirty.
180 *
181 * @ops: The ops returned from alloc_io_pgtable_ops.
182 */
183 void free_io_pgtable_ops(struct io_pgtable_ops *ops);
184
185 /**
186 * io_pgtable_alloc_pages - Allocate memory for page tables using an IOMMU
187 * driver's provided callback, or the buddy allocator.
188 *
189 * @cfg: The page table configuration. This will be used to determine if
190 * the page table memory should be allocated through the IOMMU
191 * driver's callback, or the buddy allocator.
192 * @cookie: An opaque pointer used by the IOMMU driver's callback.
193 * @order: The order of the size of the allocation.
194 * @gfp_mask: The GFP mask to be used with the allocation
195 *
196 * Returns a cacheable linear mapping address to a physically contiguous region
197 * of memory. The start of the region must be page-aligned.
198 */
199 void *io_pgtable_alloc_pages(struct io_pgtable_cfg *cfg, void *cookie,
200 int order, gfp_t gfp_mask);
201
202 /**
203 * io_pgtable_free_pages - Free memory for page tables using an IOMMU
204 * driver's provided callback, or the buddy allocator.
205 *
206 * @cfg: The page table configuration. This will be used to determine if
207 * the page table memory should be allocated through the IOMMU
208 * driver's callback, or the buddy allocator.
209 * @cookie: An opage pointer used by the IOMMU driver's callback.
210 * @virt: The virtual address of the memory to free.
211 * @order: The order of the size of the allocation.
212 */
213 void io_pgtable_free_pages(struct io_pgtable_cfg *cfg, void *cookie, void *virt,
214 int order);
215
216 /*
217 * Internal structures for page table allocator implementations.
218 */
219
220 /**
221 * struct io_pgtable - Internal structure describing a set of page tables.
222 *
223 * @fmt: The page table format.
224 * @cookie: An opaque token provided by the IOMMU driver and passed back to
225 * any callback routines.
226 * @cfg: A copy of the page table configuration.
227 * @ops: The page table operations in use for this set of page tables.
228 */
229 struct io_pgtable {
230 enum io_pgtable_fmt fmt;
231 void *cookie;
232 struct io_pgtable_cfg cfg;
233 struct io_pgtable_ops ops;
234 };
235
236 #define io_pgtable_ops_to_pgtable(x) container_of((x), struct io_pgtable, ops)
237
io_pgtable_tlb_flush_all(struct io_pgtable * iop)238 static inline void io_pgtable_tlb_flush_all(struct io_pgtable *iop)
239 {
240 iop->cfg.tlb->tlb_flush_all(iop->cookie);
241 }
242
243 static inline void
io_pgtable_tlb_flush_walk(struct io_pgtable * iop,unsigned long iova,size_t size,size_t granule)244 io_pgtable_tlb_flush_walk(struct io_pgtable *iop, unsigned long iova,
245 size_t size, size_t granule)
246 {
247 iop->cfg.tlb->tlb_flush_walk(iova, size, granule, iop->cookie);
248 }
249
250 static inline void
io_pgtable_tlb_flush_leaf(struct io_pgtable * iop,unsigned long iova,size_t size,size_t granule)251 io_pgtable_tlb_flush_leaf(struct io_pgtable *iop, unsigned long iova,
252 size_t size, size_t granule)
253 {
254 iop->cfg.tlb->tlb_flush_leaf(iova, size, granule, iop->cookie);
255 }
256
257 static inline void
io_pgtable_tlb_add_page(struct io_pgtable * iop,struct iommu_iotlb_gather * gather,unsigned long iova,size_t granule)258 io_pgtable_tlb_add_page(struct io_pgtable *iop,
259 struct iommu_iotlb_gather * gather, unsigned long iova,
260 size_t granule)
261 {
262 if (iop->cfg.tlb->tlb_add_page)
263 iop->cfg.tlb->tlb_add_page(gather, iova, granule, iop->cookie);
264 }
265
266 /**
267 * struct io_pgtable_init_fns - Alloc/free a set of page tables for a
268 * particular format.
269 *
270 * @alloc: Allocate a set of page tables described by cfg.
271 * @free: Free the page tables associated with iop.
272 */
273 struct io_pgtable_init_fns {
274 struct io_pgtable *(*alloc)(struct io_pgtable_cfg *cfg, void *cookie);
275 void (*free)(struct io_pgtable *iop);
276 };
277
278 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns;
279 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns;
280 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns;
281 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns;
282 extern struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns;
283 extern struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns;
284
285 #endif /* __IO_PGTABLE_H */
286