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 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 #define IO_PGTABLE_QUIRK_ARM_NS BIT(0)
88 #define IO_PGTABLE_QUIRK_NO_PERMS BIT(1)
89 #define IO_PGTABLE_QUIRK_TLBI_ON_MAP BIT(2)
90 #define IO_PGTABLE_QUIRK_ARM_MTK_EXT BIT(3)
91 #define IO_PGTABLE_QUIRK_NON_STRICT BIT(4)
92 unsigned long quirks;
93 unsigned long pgsize_bitmap;
94 unsigned int ias;
95 unsigned int oas;
96 bool coherent_walk;
97 const struct iommu_flush_ops *tlb;
98 struct device *iommu_dev;
99
100 /* Low-level data specific to the table format */
101 union {
102 struct {
103 u64 ttbr[2];
104 u64 tcr;
105 u64 mair[2];
106 } arm_lpae_s1_cfg;
107
108 struct {
109 u64 vttbr;
110 u64 vtcr;
111 } arm_lpae_s2_cfg;
112
113 struct {
114 u32 ttbr[2];
115 u32 tcr;
116 u32 nmrr;
117 u32 prrr;
118 } arm_v7s_cfg;
119
120 struct {
121 u64 transtab;
122 u64 memattr;
123 } arm_mali_lpae_cfg;
124 };
125 };
126
127 /**
128 * struct io_pgtable_ops - Page table manipulation API for IOMMU drivers.
129 *
130 * @map: Map a physically contiguous memory region.
131 * @unmap: Unmap a physically contiguous memory region.
132 * @iova_to_phys: Translate iova to physical address.
133 *
134 * These functions map directly onto the iommu_ops member functions with
135 * the same names.
136 */
137 struct io_pgtable_ops {
138 int (*map)(struct io_pgtable_ops *ops, unsigned long iova,
139 phys_addr_t paddr, size_t size, int prot);
140 size_t (*unmap)(struct io_pgtable_ops *ops, unsigned long iova,
141 size_t size, struct iommu_iotlb_gather *gather);
142 phys_addr_t (*iova_to_phys)(struct io_pgtable_ops *ops,
143 unsigned long iova);
144 };
145
146 /**
147 * alloc_io_pgtable_ops() - Allocate a page table allocator for use by an IOMMU.
148 *
149 * @fmt: The page table format.
150 * @cfg: The page table configuration. This will be modified to represent
151 * the configuration actually provided by the allocator (e.g. the
152 * pgsize_bitmap may be restricted).
153 * @cookie: An opaque token provided by the IOMMU driver and passed back to
154 * the callback routines in cfg->tlb.
155 */
156 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
157 struct io_pgtable_cfg *cfg,
158 void *cookie);
159
160 /**
161 * free_io_pgtable_ops() - Free an io_pgtable_ops structure. The caller
162 * *must* ensure that the page table is no longer
163 * live, but the TLB can be dirty.
164 *
165 * @ops: The ops returned from alloc_io_pgtable_ops.
166 */
167 void free_io_pgtable_ops(struct io_pgtable_ops *ops);
168
169
170 /*
171 * Internal structures for page table allocator implementations.
172 */
173
174 /**
175 * struct io_pgtable - Internal structure describing a set of page tables.
176 *
177 * @fmt: The page table format.
178 * @cookie: An opaque token provided by the IOMMU driver and passed back to
179 * any callback routines.
180 * @cfg: A copy of the page table configuration.
181 * @ops: The page table operations in use for this set of page tables.
182 */
183 struct io_pgtable {
184 enum io_pgtable_fmt fmt;
185 void *cookie;
186 struct io_pgtable_cfg cfg;
187 struct io_pgtable_ops ops;
188 };
189
190 #define io_pgtable_ops_to_pgtable(x) container_of((x), struct io_pgtable, ops)
191
192 static inline void io_pgtable_tlb_flush_all(struct io_pgtable *iop)
193 {
194 iop->cfg.tlb->tlb_flush_all(iop->cookie);
195 }
196
197 static inline void
198 io_pgtable_tlb_flush_walk(struct io_pgtable *iop, unsigned long iova,
199 size_t size, size_t granule)
200 {
201 iop->cfg.tlb->tlb_flush_walk(iova, size, granule, iop->cookie);
202 }
203
204 static inline void
205 io_pgtable_tlb_flush_leaf(struct io_pgtable *iop, unsigned long iova,
206 size_t size, size_t granule)
207 {
208 iop->cfg.tlb->tlb_flush_leaf(iova, size, granule, iop->cookie);
209 }
210
211 static inline void
212 io_pgtable_tlb_add_page(struct io_pgtable *iop,
213 struct iommu_iotlb_gather * gather, unsigned long iova,
214 size_t granule)
215 {
216 if (iop->cfg.tlb->tlb_add_page)
217 iop->cfg.tlb->tlb_add_page(gather, iova, granule, iop->cookie);
218 }
219
220 /**
221 * struct io_pgtable_init_fns - Alloc/free a set of page tables for a
222 * particular format.
223 *
224 * @alloc: Allocate a set of page tables described by cfg.
225 * @free: Free the page tables associated with iop.
226 */
227 struct io_pgtable_init_fns {
228 struct io_pgtable *(*alloc)(struct io_pgtable_cfg *cfg, void *cookie);
229 void (*free)(struct io_pgtable *iop);
230 };
231
232 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns;
233 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns;
234 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns;
235 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns;
236 extern struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns;
237 extern struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns;
238
239 #endif /* __IO_PGTABLE_H */