xref: /linux-6.15/include/linux/io-pgtable.h (revision dc09fe1c)
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 	APPLE_DART,
20 	APPLE_DART2,
21 	IO_PGTABLE_NUM_FMTS,
22 };
23 
24 /**
25  * struct iommu_flush_ops - IOMMU callbacks for TLB and page table management.
26  *
27  * @tlb_flush_all:  Synchronously invalidate the entire TLB context.
28  * @tlb_flush_walk: Synchronously invalidate all intermediate TLB state
29  *                  (sometimes referred to as the "walk cache") for a virtual
30  *                  address range.
31  * @tlb_add_page:   Optional callback to queue up leaf TLB invalidation for a
32  *                  single page.  IOMMUs that cannot batch TLB invalidation
33  *                  operations efficiently will typically issue them here, but
34  *                  others may decide to update the iommu_iotlb_gather structure
35  *                  and defer the invalidation until iommu_iotlb_sync() instead.
36  *
37  * Note that these can all be called in atomic context and must therefore
38  * not block.
39  */
40 struct iommu_flush_ops {
41 	void (*tlb_flush_all)(void *cookie);
42 	void (*tlb_flush_walk)(unsigned long iova, size_t size, size_t granule,
43 			       void *cookie);
44 	void (*tlb_add_page)(struct iommu_iotlb_gather *gather,
45 			     unsigned long iova, size_t granule, void *cookie);
46 };
47 
48 /**
49  * struct io_pgtable_cfg - Configuration data for a set of page tables.
50  *
51  * @quirks:        A bitmap of hardware quirks that require some special
52  *                 action by the low-level page table allocator.
53  * @pgsize_bitmap: A bitmap of page sizes supported by this set of page
54  *                 tables.
55  * @ias:           Input address (iova) size, in bits.
56  * @oas:           Output address (paddr) size, in bits.
57  * @coherent_walk  A flag to indicate whether or not page table walks made
58  *                 by the IOMMU are coherent with the CPU caches.
59  * @tlb:           TLB management callbacks for this set of tables.
60  * @iommu_dev:     The device representing the DMA configuration for the
61  *                 page table walker.
62  */
63 struct io_pgtable_cfg {
64 	/*
65 	 * IO_PGTABLE_QUIRK_ARM_NS: (ARM formats) Set NS and NSTABLE bits in
66 	 *	stage 1 PTEs, for hardware which insists on validating them
67 	 *	even in	non-secure state where they should normally be ignored.
68 	 *
69 	 * IO_PGTABLE_QUIRK_NO_PERMS: Ignore the IOMMU_READ, IOMMU_WRITE and
70 	 *	IOMMU_NOEXEC flags and map everything with full access, for
71 	 *	hardware which does not implement the permissions of a given
72 	 *	format, and/or requires some format-specific default value.
73 	 *
74 	 * IO_PGTABLE_QUIRK_ARM_MTK_EXT: (ARM v7s format) MediaTek IOMMUs extend
75 	 *	to support up to 35 bits PA where the bit32, bit33 and bit34 are
76 	 *	encoded in the bit9, bit4 and bit5 of the PTE respectively.
77 	 *
78 	 * IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT: (ARM v7s format) MediaTek IOMMUs
79 	 *	extend the translation table base support up to 35 bits PA, the
80 	 *	encoding format is same with IO_PGTABLE_QUIRK_ARM_MTK_EXT.
81 	 *
82 	 * IO_PGTABLE_QUIRK_ARM_TTBR1: (ARM LPAE format) Configure the table
83 	 *	for use in the upper half of a split address space.
84 	 *
85 	 * IO_PGTABLE_QUIRK_ARM_OUTER_WBWA: Override the outer-cacheability
86 	 *	attributes set in the TCR for a non-coherent page-table walker.
87 	 */
88 	#define IO_PGTABLE_QUIRK_ARM_NS			BIT(0)
89 	#define IO_PGTABLE_QUIRK_NO_PERMS		BIT(1)
90 	#define IO_PGTABLE_QUIRK_ARM_MTK_EXT		BIT(3)
91 	#define IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT	BIT(4)
92 	#define IO_PGTABLE_QUIRK_ARM_TTBR1		BIT(5)
93 	#define IO_PGTABLE_QUIRK_ARM_OUTER_WBWA		BIT(6)
94 	unsigned long			quirks;
95 	unsigned long			pgsize_bitmap;
96 	unsigned int			ias;
97 	unsigned int			oas;
98 	bool				coherent_walk;
99 	const struct iommu_flush_ops	*tlb;
100 	struct device			*iommu_dev;
101 
102 	/* Low-level data specific to the table format */
103 	union {
104 		struct {
105 			u64	ttbr;
106 			struct {
107 				u32	ips:3;
108 				u32	tg:2;
109 				u32	sh:2;
110 				u32	orgn:2;
111 				u32	irgn:2;
112 				u32	tsz:6;
113 			}	tcr;
114 			u64	mair;
115 		} arm_lpae_s1_cfg;
116 
117 		struct {
118 			u64	vttbr;
119 			struct {
120 				u32	ps:3;
121 				u32	tg:2;
122 				u32	sh:2;
123 				u32	orgn:2;
124 				u32	irgn:2;
125 				u32	sl:2;
126 				u32	tsz:6;
127 			}	vtcr;
128 		} arm_lpae_s2_cfg;
129 
130 		struct {
131 			u32	ttbr;
132 			u32	tcr;
133 			u32	nmrr;
134 			u32	prrr;
135 		} arm_v7s_cfg;
136 
137 		struct {
138 			u64	transtab;
139 			u64	memattr;
140 		} arm_mali_lpae_cfg;
141 
142 		struct {
143 			u64 ttbr[4];
144 			u32 n_ttbrs;
145 		} apple_dart_cfg;
146 	};
147 };
148 
149 /**
150  * struct io_pgtable_ops - Page table manipulation API for IOMMU drivers.
151  *
152  * @map:          Map a physically contiguous memory region.
153  * @map_pages:    Map a physically contiguous range of pages of the same size.
154  * @unmap:        Unmap a physically contiguous memory region.
155  * @unmap_pages:  Unmap a range of virtually contiguous pages of the same size.
156  * @iova_to_phys: Translate iova to physical address.
157  *
158  * These functions map directly onto the iommu_ops member functions with
159  * the same names.
160  */
161 struct io_pgtable_ops {
162 	int (*map)(struct io_pgtable_ops *ops, unsigned long iova,
163 		   phys_addr_t paddr, size_t size, int prot, gfp_t gfp);
164 	int (*map_pages)(struct io_pgtable_ops *ops, unsigned long iova,
165 			 phys_addr_t paddr, size_t pgsize, size_t pgcount,
166 			 int prot, gfp_t gfp, size_t *mapped);
167 	size_t (*unmap)(struct io_pgtable_ops *ops, unsigned long iova,
168 			size_t size, struct iommu_iotlb_gather *gather);
169 	size_t (*unmap_pages)(struct io_pgtable_ops *ops, unsigned long iova,
170 			      size_t pgsize, size_t pgcount,
171 			      struct iommu_iotlb_gather *gather);
172 	phys_addr_t (*iova_to_phys)(struct io_pgtable_ops *ops,
173 				    unsigned long iova);
174 };
175 
176 /**
177  * alloc_io_pgtable_ops() - Allocate a page table allocator for use by an IOMMU.
178  *
179  * @fmt:    The page table format.
180  * @cfg:    The page table configuration. This will be modified to represent
181  *          the configuration actually provided by the allocator (e.g. the
182  *          pgsize_bitmap may be restricted).
183  * @cookie: An opaque token provided by the IOMMU driver and passed back to
184  *          the callback routines in cfg->tlb.
185  */
186 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
187 					    struct io_pgtable_cfg *cfg,
188 					    void *cookie);
189 
190 /**
191  * free_io_pgtable_ops() - Free an io_pgtable_ops structure. The caller
192  *                         *must* ensure that the page table is no longer
193  *                         live, but the TLB can be dirty.
194  *
195  * @ops: The ops returned from alloc_io_pgtable_ops.
196  */
197 void free_io_pgtable_ops(struct io_pgtable_ops *ops);
198 
199 
200 /*
201  * Internal structures for page table allocator implementations.
202  */
203 
204 /**
205  * struct io_pgtable - Internal structure describing a set of page tables.
206  *
207  * @fmt:    The page table format.
208  * @cookie: An opaque token provided by the IOMMU driver and passed back to
209  *          any callback routines.
210  * @cfg:    A copy of the page table configuration.
211  * @ops:    The page table operations in use for this set of page tables.
212  */
213 struct io_pgtable {
214 	enum io_pgtable_fmt	fmt;
215 	void			*cookie;
216 	struct io_pgtable_cfg	cfg;
217 	struct io_pgtable_ops	ops;
218 };
219 
220 #define io_pgtable_ops_to_pgtable(x) container_of((x), struct io_pgtable, ops)
221 
222 static inline void io_pgtable_tlb_flush_all(struct io_pgtable *iop)
223 {
224 	if (iop->cfg.tlb && iop->cfg.tlb->tlb_flush_all)
225 		iop->cfg.tlb->tlb_flush_all(iop->cookie);
226 }
227 
228 static inline void
229 io_pgtable_tlb_flush_walk(struct io_pgtable *iop, unsigned long iova,
230 			  size_t size, size_t granule)
231 {
232 	if (iop->cfg.tlb && iop->cfg.tlb->tlb_flush_walk)
233 		iop->cfg.tlb->tlb_flush_walk(iova, size, granule, iop->cookie);
234 }
235 
236 static inline void
237 io_pgtable_tlb_add_page(struct io_pgtable *iop,
238 			struct iommu_iotlb_gather * gather, unsigned long iova,
239 			size_t granule)
240 {
241 	if (iop->cfg.tlb && iop->cfg.tlb->tlb_add_page)
242 		iop->cfg.tlb->tlb_add_page(gather, iova, granule, iop->cookie);
243 }
244 
245 /**
246  * struct io_pgtable_init_fns - Alloc/free a set of page tables for a
247  *                              particular format.
248  *
249  * @alloc: Allocate a set of page tables described by cfg.
250  * @free:  Free the page tables associated with iop.
251  */
252 struct io_pgtable_init_fns {
253 	struct io_pgtable *(*alloc)(struct io_pgtable_cfg *cfg, void *cookie);
254 	void (*free)(struct io_pgtable *iop);
255 };
256 
257 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns;
258 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns;
259 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns;
260 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns;
261 extern struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns;
262 extern struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns;
263 extern struct io_pgtable_init_fns io_pgtable_amd_iommu_v1_init_fns;
264 extern struct io_pgtable_init_fns io_pgtable_apple_dart_init_fns;
265 
266 #endif /* __IO_PGTABLE_H */
267