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 AMD_IOMMU_V1,
19 AMD_IOMMU_V2,
20 APPLE_DART,
21 APPLE_DART2,
22 IO_PGTABLE_NUM_FMTS,
23 };
24
25 /**
26 * struct iommu_flush_ops - IOMMU callbacks for TLB and page table management.
27 *
28 * @tlb_flush_all: Synchronously invalidate the entire TLB context.
29 * @tlb_flush_walk: Synchronously invalidate all intermediate TLB state
30 * (sometimes referred to as the "walk cache") for a virtual
31 * address range.
32 * @tlb_add_page: Optional callback to queue up leaf TLB invalidation for a
33 * single page. IOMMUs that cannot batch TLB invalidation
34 * operations efficiently will typically issue them here, but
35 * others may decide to update the iommu_iotlb_gather structure
36 * and defer the invalidation until iommu_iotlb_sync() instead.
37 *
38 * Note that these can all be called in atomic context and must therefore
39 * not block.
40 */
41 struct iommu_flush_ops {
42 void (*tlb_flush_all)(void *cookie);
43 void (*tlb_flush_walk)(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 io_pgtable_cfg - Configuration data for a set of page tables.
51 *
52 * @quirks: A bitmap of hardware quirks that require some special
53 * action by the low-level page table allocator.
54 * @pgsize_bitmap: A bitmap of page sizes supported by this set of page
55 * tables.
56 * @ias: Input address (iova) size, in bits.
57 * @oas: Output address (paddr) size, in bits.
58 * @coherent_walk A flag to indicate whether or not page table walks made
59 * by the IOMMU are coherent with the CPU caches.
60 * @tlb: TLB management callbacks for this set of tables.
61 * @iommu_dev: The device representing the DMA configuration for the
62 * page table walker.
63 */
64 struct io_pgtable_cfg {
65 /*
66 * IO_PGTABLE_QUIRK_ARM_NS: (ARM formats) Set NS and NSTABLE bits in
67 * stage 1 PTEs, for hardware which insists on validating them
68 * even in non-secure state where they should normally be ignored.
69 *
70 * IO_PGTABLE_QUIRK_NO_PERMS: Ignore the IOMMU_READ, IOMMU_WRITE and
71 * IOMMU_NOEXEC flags and map everything with full access, for
72 * hardware which does not implement the permissions of a given
73 * format, and/or requires some format-specific default value.
74 *
75 * IO_PGTABLE_QUIRK_ARM_MTK_EXT: (ARM v7s format) MediaTek IOMMUs extend
76 * to support up to 35 bits PA where the bit32, bit33 and bit34 are
77 * encoded in the bit9, bit4 and bit5 of the PTE respectively.
78 *
79 * IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT: (ARM v7s format) MediaTek IOMMUs
80 * extend the translation table base support up to 35 bits PA, the
81 * encoding format is same with IO_PGTABLE_QUIRK_ARM_MTK_EXT.
82 *
83 * IO_PGTABLE_QUIRK_ARM_TTBR1: (ARM LPAE format) Configure the table
84 * for use in the upper half of a split address space.
85 *
86 * IO_PGTABLE_QUIRK_ARM_OUTER_WBWA: Override the outer-cacheability
87 * attributes set in the TCR for a non-coherent page-table walker.
88 *
89 * IO_PGTABLE_QUIRK_ARM_HD: Enables dirty tracking in stage 1 pagetable.
90 * IO_PGTABLE_QUIRK_ARM_S2FWB: Use the FWB format for the MemAttrs bits
91 *
92 * IO_PGTABLE_QUIRK_NO_WARN: Do not WARN_ON() on conflicting
93 * mappings, but silently return -EEXISTS. Normally an attempt
94 * to map over an existing mapping would indicate some sort of
95 * kernel bug, which would justify the WARN_ON(). But for GPU
96 * drivers, this could be under control of userspace. Which
97 * deserves an error return, but not to spam dmesg.
98 */
99 #define IO_PGTABLE_QUIRK_ARM_NS BIT(0)
100 #define IO_PGTABLE_QUIRK_NO_PERMS BIT(1)
101 #define IO_PGTABLE_QUIRK_ARM_MTK_EXT BIT(3)
102 #define IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT BIT(4)
103 #define IO_PGTABLE_QUIRK_ARM_TTBR1 BIT(5)
104 #define IO_PGTABLE_QUIRK_ARM_OUTER_WBWA BIT(6)
105 #define IO_PGTABLE_QUIRK_ARM_HD BIT(7)
106 #define IO_PGTABLE_QUIRK_ARM_S2FWB BIT(8)
107 #define IO_PGTABLE_QUIRK_NO_WARN BIT(9)
108 unsigned long quirks;
109 unsigned long pgsize_bitmap;
110 unsigned int ias;
111 unsigned int oas;
112 bool coherent_walk;
113 const struct iommu_flush_ops *tlb;
114 struct device *iommu_dev;
115
116 /**
117 * @alloc: Custom page allocator.
118 *
119 * Optional hook used to allocate page tables. If this function is NULL,
120 * @free must be NULL too.
121 *
122 * Memory returned should be zeroed and suitable for dma_map_single() and
123 * virt_to_phys().
124 *
125 * Not all formats support custom page allocators. Before considering
126 * passing a non-NULL value, make sure the chosen page format supports
127 * this feature.
128 */
129 void *(*alloc)(void *cookie, size_t size, gfp_t gfp);
130
131 /**
132 * @free: Custom page de-allocator.
133 *
134 * Optional hook used to free page tables allocated with the @alloc
135 * hook. Must be non-NULL if @alloc is not NULL, must be NULL
136 * otherwise.
137 */
138 void (*free)(void *cookie, void *pages, size_t size);
139
140 /* Low-level data specific to the table format */
141 union {
142 struct {
143 u64 ttbr;
144 struct {
145 u32 ips:3;
146 u32 tg:2;
147 u32 sh:2;
148 u32 orgn:2;
149 u32 irgn:2;
150 u32 tsz:6;
151 } tcr;
152 u64 mair;
153 } arm_lpae_s1_cfg;
154
155 struct {
156 u64 vttbr;
157 struct {
158 u32 ps:3;
159 u32 tg:2;
160 u32 sh:2;
161 u32 orgn:2;
162 u32 irgn:2;
163 u32 sl:2;
164 u32 tsz:6;
165 } vtcr;
166 } arm_lpae_s2_cfg;
167
168 struct {
169 u32 ttbr;
170 u32 tcr;
171 u32 nmrr;
172 u32 prrr;
173 } arm_v7s_cfg;
174
175 struct {
176 u64 transtab;
177 u64 memattr;
178 } arm_mali_lpae_cfg;
179
180 struct {
181 u64 ttbr[4];
182 u32 n_ttbrs;
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 *
208 * These functions map directly onto the iommu_ops member functions with
209 * the same names.
210 */
211 struct io_pgtable_ops {
212 int (*map_pages)(struct io_pgtable_ops *ops, unsigned long iova,
213 phys_addr_t paddr, size_t pgsize, size_t pgcount,
214 int prot, gfp_t gfp, size_t *mapped);
215 size_t (*unmap_pages)(struct io_pgtable_ops *ops, unsigned long iova,
216 size_t pgsize, size_t pgcount,
217 struct iommu_iotlb_gather *gather);
218 phys_addr_t (*iova_to_phys)(struct io_pgtable_ops *ops,
219 unsigned long iova);
220 int (*pgtable_walk)(struct io_pgtable_ops *ops, unsigned long iova, void *wd);
221 int (*read_and_clear_dirty)(struct io_pgtable_ops *ops,
222 unsigned long iova, size_t size,
223 unsigned long flags,
224 struct iommu_dirty_bitmap *dirty);
225 };
226
227 /**
228 * alloc_io_pgtable_ops() - Allocate a page table allocator for use by an IOMMU.
229 *
230 * @fmt: The page table format.
231 * @cfg: The page table configuration. This will be modified to represent
232 * the configuration actually provided by the allocator (e.g. the
233 * pgsize_bitmap may be restricted).
234 * @cookie: An opaque token provided by the IOMMU driver and passed back to
235 * the callback routines in cfg->tlb.
236 */
237 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
238 struct io_pgtable_cfg *cfg,
239 void *cookie);
240
241 /**
242 * free_io_pgtable_ops() - Free an io_pgtable_ops structure. The caller
243 * *must* ensure that the page table is no longer
244 * live, but the TLB can be dirty.
245 *
246 * @ops: The ops returned from alloc_io_pgtable_ops.
247 */
248 void free_io_pgtable_ops(struct io_pgtable_ops *ops);
249
250
251 /*
252 * Internal structures for page table allocator implementations.
253 */
254
255 /**
256 * struct io_pgtable - Internal structure describing a set of page tables.
257 *
258 * @fmt: The page table format.
259 * @cookie: An opaque token provided by the IOMMU driver and passed back to
260 * any callback routines.
261 * @cfg: A copy of the page table configuration.
262 * @ops: The page table operations in use for this set of page tables.
263 */
264 struct io_pgtable {
265 enum io_pgtable_fmt fmt;
266 void *cookie;
267 struct io_pgtable_cfg cfg;
268 struct io_pgtable_ops ops;
269 };
270
271 #define io_pgtable_ops_to_pgtable(x) container_of((x), struct io_pgtable, ops)
272
io_pgtable_tlb_flush_all(struct io_pgtable * iop)273 static inline void io_pgtable_tlb_flush_all(struct io_pgtable *iop)
274 {
275 if (iop->cfg.tlb && iop->cfg.tlb->tlb_flush_all)
276 iop->cfg.tlb->tlb_flush_all(iop->cookie);
277 }
278
279 static inline void
io_pgtable_tlb_flush_walk(struct io_pgtable * iop,unsigned long iova,size_t size,size_t granule)280 io_pgtable_tlb_flush_walk(struct io_pgtable *iop, unsigned long iova,
281 size_t size, size_t granule)
282 {
283 if (iop->cfg.tlb && iop->cfg.tlb->tlb_flush_walk)
284 iop->cfg.tlb->tlb_flush_walk(iova, size, granule, iop->cookie);
285 }
286
287 static inline void
io_pgtable_tlb_add_page(struct io_pgtable * iop,struct iommu_iotlb_gather * gather,unsigned long iova,size_t granule)288 io_pgtable_tlb_add_page(struct io_pgtable *iop,
289 struct iommu_iotlb_gather * gather, unsigned long iova,
290 size_t granule)
291 {
292 if (iop->cfg.tlb && iop->cfg.tlb->tlb_add_page)
293 iop->cfg.tlb->tlb_add_page(gather, iova, granule, iop->cookie);
294 }
295
296 /**
297 * enum io_pgtable_caps - IO page table backend capabilities.
298 */
299 enum io_pgtable_caps {
300 /** @IO_PGTABLE_CAP_CUSTOM_ALLOCATOR: Backend accepts custom page table allocators. */
301 IO_PGTABLE_CAP_CUSTOM_ALLOCATOR = BIT(0),
302 };
303
304 /**
305 * struct io_pgtable_init_fns - Alloc/free a set of page tables for a
306 * particular format.
307 *
308 * @alloc: Allocate a set of page tables described by cfg.
309 * @free: Free the page tables associated with iop.
310 * @caps: Combination of @io_pgtable_caps flags encoding the backend capabilities.
311 */
312 struct io_pgtable_init_fns {
313 struct io_pgtable *(*alloc)(struct io_pgtable_cfg *cfg, void *cookie);
314 void (*free)(struct io_pgtable *iop);
315 u32 caps;
316 };
317
318 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns;
319 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns;
320 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns;
321 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns;
322 extern struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns;
323 extern struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns;
324 extern struct io_pgtable_init_fns io_pgtable_amd_iommu_v1_init_fns;
325 extern struct io_pgtable_init_fns io_pgtable_amd_iommu_v2_init_fns;
326 extern struct io_pgtable_init_fns io_pgtable_apple_dart_init_fns;
327
328 #endif /* __IO_PGTABLE_H */
329