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 APPLE_DART,
19 APPLE_DART2,
20 IO_PGTABLE_NUM_FMTS,
21 };
22
23 /**
24 * struct iommu_flush_ops - IOMMU callbacks for TLB and page table management.
25 *
26 * @tlb_flush_all: Synchronously invalidate the entire TLB context.
27 * @tlb_flush_walk: Synchronously invalidate all intermediate TLB state
28 * (sometimes referred to as the "walk cache") 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_iotlb_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_add_page)(struct iommu_iotlb_gather *gather,
44 unsigned long iova, size_t granule, void *cookie);
45 };
46
47 /**
48 * struct io_pgtable_cfg - Configuration data for a set of page tables.
49 *
50 * @quirks: A bitmap of hardware quirks that require some special
51 * action by the low-level page table allocator.
52 * @pgsize_bitmap: A bitmap of page sizes supported by this set of page
53 * tables.
54 * @ias: Input address (iova) size, in bits.
55 * @oas: Output address (paddr) size, in bits.
56 * @coherent_walk: A flag to indicate whether or not page table walks made
57 * by the IOMMU are coherent with the CPU caches.
58 * @tlb: TLB management callbacks for this set of tables.
59 * @iommu_dev: The device representing the DMA configuration for the
60 * page table walker.
61 */
62 struct io_pgtable_cfg {
63 /*
64 * IO_PGTABLE_QUIRK_ARM_NS: (ARM formats) Set NS and NSTABLE bits in
65 * stage 1 PTEs, for hardware which insists on validating them
66 * even in non-secure state where they should normally be ignored.
67 *
68 * IO_PGTABLE_QUIRK_NO_PERMS: Ignore the IOMMU_READ, IOMMU_WRITE and
69 * IOMMU_NOEXEC flags and map everything with full access, for
70 * hardware which does not implement the permissions of a given
71 * format, and/or requires some format-specific default value.
72 *
73 * IO_PGTABLE_QUIRK_ARM_MTK_EXT: (ARM v7s format) MediaTek IOMMUs extend
74 * to support up to 35 bits PA where the bit32, bit33 and bit34 are
75 * encoded in the bit9, bit4 and bit5 of the PTE respectively.
76 *
77 * IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT: (ARM v7s format) MediaTek IOMMUs
78 * extend the translation table base support up to 35 bits PA, the
79 * encoding format is same with IO_PGTABLE_QUIRK_ARM_MTK_EXT.
80 *
81 * IO_PGTABLE_QUIRK_ARM_TTBR1: (ARM LPAE format) Configure the table
82 * for use in the upper half of a split address space.
83 *
84 * IO_PGTABLE_QUIRK_ARM_OUTER_WBWA: Override the outer-cacheability
85 * attributes set in the TCR for a non-coherent page-table walker.
86 *
87 * IO_PGTABLE_QUIRK_ARM_HD: Enables dirty tracking in stage 1 pagetable.
88 * IO_PGTABLE_QUIRK_ARM_S2FWB: Use the FWB format for the MemAttrs bits
89 *
90 * IO_PGTABLE_QUIRK_NO_WARN: Do not WARN_ON() on conflicting
91 * mappings, but silently return -EEXISTS. Normally an attempt
92 * to map over an existing mapping would indicate some sort of
93 * kernel bug, which would justify the WARN_ON(). But for GPU
94 * drivers, this could be under control of userspace. Which
95 * deserves an error return, but not to spam dmesg.
96 */
97 #define IO_PGTABLE_QUIRK_ARM_NS BIT(0)
98 #define IO_PGTABLE_QUIRK_NO_PERMS BIT(1)
99 #define IO_PGTABLE_QUIRK_ARM_MTK_EXT BIT(3)
100 #define IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT BIT(4)
101 #define IO_PGTABLE_QUIRK_ARM_TTBR1 BIT(5)
102 #define IO_PGTABLE_QUIRK_ARM_OUTER_WBWA BIT(6)
103 #define IO_PGTABLE_QUIRK_ARM_HD BIT(7)
104 #define IO_PGTABLE_QUIRK_ARM_S2FWB BIT(8)
105 #define IO_PGTABLE_QUIRK_NO_WARN BIT(9)
106 unsigned long quirks;
107 unsigned long pgsize_bitmap;
108 unsigned int ias;
109 unsigned int oas;
110 bool coherent_walk;
111 const struct iommu_flush_ops *tlb;
112 struct device *iommu_dev;
113
114 /**
115 * @alloc: Custom page allocator.
116 *
117 * Optional hook used to allocate page tables. If this function is NULL,
118 * @free must be NULL too.
119 *
120 * Memory returned should be zeroed and suitable for dma_map_single() and
121 * virt_to_phys().
122 *
123 * Not all formats support custom page allocators. Before considering
124 * passing a non-NULL value, make sure the chosen page format supports
125 * this feature.
126 */
127 void *(*alloc)(void *cookie, size_t size, gfp_t gfp);
128
129 /**
130 * @free: Custom page de-allocator.
131 *
132 * Optional hook used to free page tables allocated with the @alloc
133 * hook. Must be non-NULL if @alloc is not NULL, must be NULL
134 * otherwise.
135 */
136 void (*free)(void *cookie, void *pages, size_t size);
137
138 /* Low-level data specific to the table format */
139 /* private: */
140 union {
141 struct {
142 u64 ttbr;
143 struct {
144 u32 ips:3;
145 u32 tg:2;
146 u32 sh:2;
147 u32 orgn:2;
148 u32 irgn:2;
149 u32 tsz:6;
150 } tcr;
151 u64 mair;
152 } arm_lpae_s1_cfg;
153
154 struct {
155 u64 vttbr;
156 struct {
157 u32 ps:3;
158 u32 tg:2;
159 u32 sh:2;
160 u32 orgn:2;
161 u32 irgn:2;
162 u32 sl:2;
163 u32 tsz:6;
164 } vtcr;
165 } arm_lpae_s2_cfg;
166
167 struct {
168 u32 ttbr;
169 u32 tcr;
170 u32 nmrr;
171 u32 prrr;
172 } arm_v7s_cfg;
173
174 struct {
175 u64 transtab;
176 u64 memattr;
177 } arm_mali_lpae_cfg;
178
179 struct {
180 u64 ttbr[4];
181 u32 n_ttbrs;
182 u32 n_levels;
183 } apple_dart_cfg;
184
185 struct {
186 int nid;
187 } amd;
188 };
189 };
190
191 /**
192 * struct arm_lpae_io_pgtable_walk_data - information from a pgtable walk
193 *
194 * @ptes: The recorded PTE values from the walk
195 */
196 struct arm_lpae_io_pgtable_walk_data {
197 u64 ptes[4];
198 };
199
200 /**
201 * struct io_pgtable_ops - Page table manipulation API for IOMMU drivers.
202 *
203 * @map_pages: Map a physically contiguous range of pages of the same size.
204 * @unmap_pages: Unmap a range of virtually contiguous pages of the same size.
205 * @iova_to_phys: Translate iova to physical address.
206 * @pgtable_walk: (optional) Perform a page table walk for a given iova.
207 * @read_and_clear_dirty: Record dirty info per IOVA. If an IOVA is dirty,
208 * clear its dirty state from the PTE unless the
209 * IOMMU_DIRTY_NO_CLEAR flag is passed in.
210 *
211 * These functions map directly onto the iommu_ops member functions with
212 * the same names.
213 */
214 struct io_pgtable_ops {
215 int (*map_pages)(struct io_pgtable_ops *ops, unsigned long iova,
216 phys_addr_t paddr, size_t pgsize, size_t pgcount,
217 int prot, gfp_t gfp, size_t *mapped);
218 size_t (*unmap_pages)(struct io_pgtable_ops *ops, unsigned long iova,
219 size_t pgsize, size_t pgcount,
220 struct iommu_iotlb_gather *gather);
221 phys_addr_t (*iova_to_phys)(struct io_pgtable_ops *ops,
222 unsigned long iova);
223 int (*pgtable_walk)(struct io_pgtable_ops *ops, unsigned long iova, void *wd);
224 int (*read_and_clear_dirty)(struct io_pgtable_ops *ops,
225 unsigned long iova, size_t size,
226 unsigned long flags,
227 struct iommu_dirty_bitmap *dirty);
228 };
229
230 /**
231 * alloc_io_pgtable_ops() - Allocate a page table allocator for use by an IOMMU.
232 *
233 * @fmt: The page table format.
234 * @cfg: The page table configuration. This will be modified to represent
235 * the configuration actually provided by the allocator (e.g. the
236 * pgsize_bitmap may be restricted).
237 * @cookie: An opaque token provided by the IOMMU driver and passed back to
238 * the callback routines.
239 *
240 * Returns: Pointer to the &struct io_pgtable_ops for this set of page tables.
241 */
242 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
243 struct io_pgtable_cfg *cfg,
244 void *cookie);
245
246 /**
247 * free_io_pgtable_ops() - Free an io_pgtable_ops structure. The caller
248 * *must* ensure that the page table is no longer
249 * live, but the TLB can be dirty.
250 *
251 * @ops: The ops returned from alloc_io_pgtable_ops.
252 */
253 void free_io_pgtable_ops(struct io_pgtable_ops *ops);
254
255
256 /*
257 * Internal structures for page table allocator implementations.
258 */
259
260 /**
261 * struct io_pgtable - Internal structure describing a set of page tables.
262 *
263 * @fmt: The page table format.
264 * @cookie: An opaque token provided by the IOMMU driver and passed back to
265 * any callback routines.
266 * @cfg: A copy of the page table configuration.
267 * @ops: The page table operations in use for this set of page tables.
268 */
269 struct io_pgtable {
270 enum io_pgtable_fmt fmt;
271 void *cookie;
272 struct io_pgtable_cfg cfg;
273 struct io_pgtable_ops ops;
274 };
275
276 #define io_pgtable_ops_to_pgtable(x) container_of((x), struct io_pgtable, ops)
277
io_pgtable_tlb_flush_all(struct io_pgtable * iop)278 static inline void io_pgtable_tlb_flush_all(struct io_pgtable *iop)
279 {
280 if (iop->cfg.tlb && iop->cfg.tlb->tlb_flush_all)
281 iop->cfg.tlb->tlb_flush_all(iop->cookie);
282 }
283
284 static inline void
io_pgtable_tlb_flush_walk(struct io_pgtable * iop,unsigned long iova,size_t size,size_t granule)285 io_pgtable_tlb_flush_walk(struct io_pgtable *iop, unsigned long iova,
286 size_t size, size_t granule)
287 {
288 if (iop->cfg.tlb && iop->cfg.tlb->tlb_flush_walk)
289 iop->cfg.tlb->tlb_flush_walk(iova, size, granule, iop->cookie);
290 }
291
292 static inline void
io_pgtable_tlb_add_page(struct io_pgtable * iop,struct iommu_iotlb_gather * gather,unsigned long iova,size_t granule)293 io_pgtable_tlb_add_page(struct io_pgtable *iop,
294 struct iommu_iotlb_gather * gather, unsigned long iova,
295 size_t granule)
296 {
297 if (iop->cfg.tlb && iop->cfg.tlb->tlb_add_page)
298 iop->cfg.tlb->tlb_add_page(gather, iova, granule, iop->cookie);
299 }
300
301 /**
302 * enum io_pgtable_caps - IO page table backend capabilities.
303 */
304 enum io_pgtable_caps {
305 /** @IO_PGTABLE_CAP_CUSTOM_ALLOCATOR: Backend accepts custom page table allocators. */
306 IO_PGTABLE_CAP_CUSTOM_ALLOCATOR = BIT(0),
307 };
308
309 /**
310 * struct io_pgtable_init_fns - Alloc/free a set of page tables for a
311 * particular format.
312 *
313 * @alloc: Allocate a set of page tables described by cfg.
314 * @free: Free the page tables associated with iop.
315 * @caps: Combination of @io_pgtable_caps flags encoding the backend capabilities.
316 */
317 struct io_pgtable_init_fns {
318 struct io_pgtable *(*alloc)(struct io_pgtable_cfg *cfg, void *cookie);
319 void (*free)(struct io_pgtable *iop);
320 u32 caps;
321 };
322
323 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns;
324 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns;
325 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns;
326 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns;
327 extern struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns;
328 extern struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns;
329 extern struct io_pgtable_init_fns io_pgtable_amd_iommu_v1_init_fns;
330 extern struct io_pgtable_init_fns io_pgtable_amd_iommu_v2_init_fns;
331 extern struct io_pgtable_init_fns io_pgtable_apple_dart_init_fns;
332
333 #endif /* __IO_PGTABLE_H */
334