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_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_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 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_TLBI_ON_MAP: If the format forbids caching invalid
76 * (unmapped) entries but the hardware might do so anyway, perform
77 * TLB maintenance when mapping as well as when unmapping.
78 *
79 * IO_PGTABLE_QUIRK_ARM_MTK_EXT: (ARM v7s format) MediaTek IOMMUs extend
80 * to support up to 34 bits PA where the bit32 and bit33 are
81 * encoded in the bit9 and bit4 of the PTE respectively.
82 *
83 * IO_PGTABLE_QUIRK_NON_STRICT: Skip issuing synchronous leaf TLBIs
84 * on unmap, for DMA domains using the flush queue mechanism for
85 * delayed invalidation.
86 *
87 * IO_PGTABLE_QUIRK_ARM_TTBR1: (ARM LPAE format) Configure the table
88 * for use in the upper half of a split address space.
89 */
90 #define IO_PGTABLE_QUIRK_ARM_NS BIT(0)
91 #define IO_PGTABLE_QUIRK_NO_PERMS BIT(1)
92 #define IO_PGTABLE_QUIRK_TLBI_ON_MAP BIT(2)
93 #define IO_PGTABLE_QUIRK_ARM_MTK_EXT BIT(3)
94 #define IO_PGTABLE_QUIRK_NON_STRICT BIT(4)
95 #define IO_PGTABLE_QUIRK_ARM_TTBR1 BIT(5)
96 unsigned long quirks;
97 unsigned long pgsize_bitmap;
98 unsigned int ias;
99 unsigned int oas;
100 bool coherent_walk;
101 const struct iommu_flush_ops *tlb;
102 struct device *iommu_dev;
103
104 /* Low-level data specific to the table format */
105 union {
106 struct {
107 u64 ttbr;
108 struct {
109 u32 ips:3;
110 u32 tg:2;
111 u32 sh:2;
112 u32 orgn:2;
113 u32 irgn:2;
114 u32 tsz:6;
115 } tcr;
116 u64 mair;
117 } arm_lpae_s1_cfg;
118
119 struct {
120 u64 vttbr;
121 struct {
122 u32 ps:3;
123 u32 tg:2;
124 u32 sh:2;
125 u32 orgn:2;
126 u32 irgn:2;
127 u32 sl:2;
128 u32 tsz:6;
129 } vtcr;
130 } arm_lpae_s2_cfg;
131
132 struct {
133 u32 ttbr;
134 u32 tcr;
135 u32 nmrr;
136 u32 prrr;
137 } arm_v7s_cfg;
138
139 struct {
140 u64 transtab;
141 u64 memattr;
142 } arm_mali_lpae_cfg;
143 };
144 };
145
146 /**
147 * struct io_pgtable_ops - Page table manipulation API for IOMMU drivers.
148 *
149 * @map: Map a physically contiguous memory region.
150 * @unmap: Unmap a physically contiguous memory region.
151 * @iova_to_phys: Translate iova to physical address.
152 *
153 * These functions map directly onto the iommu_ops member functions with
154 * the same names.
155 */
156 struct io_pgtable_ops {
157 int (*map)(struct io_pgtable_ops *ops, unsigned long iova,
158 phys_addr_t paddr, size_t size, int prot, gfp_t gfp);
159 size_t (*unmap)(struct io_pgtable_ops *ops, unsigned long iova,
160 size_t size, struct iommu_iotlb_gather *gather);
161 phys_addr_t (*iova_to_phys)(struct io_pgtable_ops *ops,
162 unsigned long iova);
163 };
164
165 /**
166 * alloc_io_pgtable_ops() - Allocate a page table allocator for use by an IOMMU.
167 *
168 * @fmt: The page table format.
169 * @cfg: The page table configuration. This will be modified to represent
170 * the configuration actually provided by the allocator (e.g. the
171 * pgsize_bitmap may be restricted).
172 * @cookie: An opaque token provided by the IOMMU driver and passed back to
173 * the callback routines in cfg->tlb.
174 */
175 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
176 struct io_pgtable_cfg *cfg,
177 void *cookie);
178
179 /**
180 * free_io_pgtable_ops() - Free an io_pgtable_ops structure. The caller
181 * *must* ensure that the page table is no longer
182 * live, but the TLB can be dirty.
183 *
184 * @ops: The ops returned from alloc_io_pgtable_ops.
185 */
186 void free_io_pgtable_ops(struct io_pgtable_ops *ops);
187
188
189 /*
190 * Internal structures for page table allocator implementations.
191 */
192
193 /**
194 * struct io_pgtable - Internal structure describing a set of page tables.
195 *
196 * @fmt: The page table format.
197 * @cookie: An opaque token provided by the IOMMU driver and passed back to
198 * any callback routines.
199 * @cfg: A copy of the page table configuration.
200 * @ops: The page table operations in use for this set of page tables.
201 */
202 struct io_pgtable {
203 enum io_pgtable_fmt fmt;
204 void *cookie;
205 struct io_pgtable_cfg cfg;
206 struct io_pgtable_ops ops;
207 };
208
209 #define io_pgtable_ops_to_pgtable(x) container_of((x), struct io_pgtable, ops)
210
io_pgtable_tlb_flush_all(struct io_pgtable * iop)211 static inline void io_pgtable_tlb_flush_all(struct io_pgtable *iop)
212 {
213 iop->cfg.tlb->tlb_flush_all(iop->cookie);
214 }
215
216 static inline void
io_pgtable_tlb_flush_walk(struct io_pgtable * iop,unsigned long iova,size_t size,size_t granule)217 io_pgtable_tlb_flush_walk(struct io_pgtable *iop, unsigned long iova,
218 size_t size, size_t granule)
219 {
220 iop->cfg.tlb->tlb_flush_walk(iova, size, granule, iop->cookie);
221 }
222
223 static inline void
io_pgtable_tlb_flush_leaf(struct io_pgtable * iop,unsigned long iova,size_t size,size_t granule)224 io_pgtable_tlb_flush_leaf(struct io_pgtable *iop, unsigned long iova,
225 size_t size, size_t granule)
226 {
227 iop->cfg.tlb->tlb_flush_leaf(iova, size, granule, iop->cookie);
228 }
229
230 static inline void
io_pgtable_tlb_add_page(struct io_pgtable * iop,struct iommu_iotlb_gather * gather,unsigned long iova,size_t granule)231 io_pgtable_tlb_add_page(struct io_pgtable *iop,
232 struct iommu_iotlb_gather * gather, unsigned long iova,
233 size_t granule)
234 {
235 if (iop->cfg.tlb->tlb_add_page)
236 iop->cfg.tlb->tlb_add_page(gather, iova, granule, iop->cookie);
237 }
238
239 /**
240 * struct io_pgtable_init_fns - Alloc/free a set of page tables for a
241 * particular format.
242 *
243 * @alloc: Allocate a set of page tables described by cfg.
244 * @free: Free the page tables associated with iop.
245 */
246 struct io_pgtable_init_fns {
247 struct io_pgtable *(*alloc)(struct io_pgtable_cfg *cfg, void *cookie);
248 void (*free)(struct io_pgtable *iop);
249 };
250
251 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns;
252 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns;
253 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns;
254 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns;
255 extern struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns;
256 extern struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns;
257
258 #endif /* __IO_PGTABLE_H */
259
