xref: /linux/include/linux/io-pgtable.h (revision cbac924200b838cfb8d8b1415113d788089dc50b)
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 	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_TTBR1: (ARM LPAE format) Configure the table
78 	 *	for use in the upper half of a split address space.
79 	 *
80 	 * IO_PGTABLE_QUIRK_ARM_OUTER_WBWA: Override the outer-cacheability
81 	 *	attributes set in the TCR for a non-coherent page-table walker.
82 	 */
83 	#define IO_PGTABLE_QUIRK_ARM_NS		BIT(0)
84 	#define IO_PGTABLE_QUIRK_NO_PERMS	BIT(1)
85 	#define IO_PGTABLE_QUIRK_ARM_MTK_EXT	BIT(3)
86 	#define IO_PGTABLE_QUIRK_ARM_TTBR1	BIT(5)
87 	#define IO_PGTABLE_QUIRK_ARM_OUTER_WBWA	BIT(6)
88 	unsigned long			quirks;
89 	unsigned long			pgsize_bitmap;
90 	unsigned int			ias;
91 	unsigned int			oas;
92 	bool				coherent_walk;
93 	const struct iommu_flush_ops	*tlb;
94 	struct device			*iommu_dev;
95 
96 	/* Low-level data specific to the table format */
97 	union {
98 		struct {
99 			u64	ttbr;
100 			struct {
101 				u32	ips:3;
102 				u32	tg:2;
103 				u32	sh:2;
104 				u32	orgn:2;
105 				u32	irgn:2;
106 				u32	tsz:6;
107 			}	tcr;
108 			u64	mair;
109 		} arm_lpae_s1_cfg;
110 
111 		struct {
112 			u64	vttbr;
113 			struct {
114 				u32	ps:3;
115 				u32	tg:2;
116 				u32	sh:2;
117 				u32	orgn:2;
118 				u32	irgn:2;
119 				u32	sl:2;
120 				u32	tsz:6;
121 			}	vtcr;
122 		} arm_lpae_s2_cfg;
123 
124 		struct {
125 			u32	ttbr;
126 			u32	tcr;
127 			u32	nmrr;
128 			u32	prrr;
129 		} arm_v7s_cfg;
130 
131 		struct {
132 			u64	transtab;
133 			u64	memattr;
134 		} arm_mali_lpae_cfg;
135 
136 		struct {
137 			u64 ttbr[4];
138 			u32 n_ttbrs;
139 		} apple_dart_cfg;
140 	};
141 };
142 
143 /**
144  * struct io_pgtable_ops - Page table manipulation API for IOMMU drivers.
145  *
146  * @map:          Map a physically contiguous memory region.
147  * @map_pages:    Map a physically contiguous range of pages of the same size.
148  * @unmap:        Unmap a physically contiguous memory region.
149  * @unmap_pages:  Unmap a range of virtually contiguous pages of the same size.
150  * @iova_to_phys: Translate iova to physical address.
151  *
152  * These functions map directly onto the iommu_ops member functions with
153  * the same names.
154  */
155 struct io_pgtable_ops {
156 	int (*map)(struct io_pgtable_ops *ops, unsigned long iova,
157 		   phys_addr_t paddr, size_t size, int prot, gfp_t gfp);
158 	int (*map_pages)(struct io_pgtable_ops *ops, unsigned long iova,
159 			 phys_addr_t paddr, size_t pgsize, size_t pgcount,
160 			 int prot, gfp_t gfp, size_t *mapped);
161 	size_t (*unmap)(struct io_pgtable_ops *ops, unsigned long iova,
162 			size_t size, struct iommu_iotlb_gather *gather);
163 	size_t (*unmap_pages)(struct io_pgtable_ops *ops, unsigned long iova,
164 			      size_t pgsize, size_t pgcount,
165 			      struct iommu_iotlb_gather *gather);
166 	phys_addr_t (*iova_to_phys)(struct io_pgtable_ops *ops,
167 				    unsigned long iova);
168 };
169 
170 /**
171  * alloc_io_pgtable_ops() - Allocate a page table allocator for use by an IOMMU.
172  *
173  * @fmt:    The page table format.
174  * @cfg:    The page table configuration. This will be modified to represent
175  *          the configuration actually provided by the allocator (e.g. the
176  *          pgsize_bitmap may be restricted).
177  * @cookie: An opaque token provided by the IOMMU driver and passed back to
178  *          the callback routines in cfg->tlb.
179  */
180 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
181 					    struct io_pgtable_cfg *cfg,
182 					    void *cookie);
183 
184 /**
185  * free_io_pgtable_ops() - Free an io_pgtable_ops structure. The caller
186  *                         *must* ensure that the page table is no longer
187  *                         live, but the TLB can be dirty.
188  *
189  * @ops: The ops returned from alloc_io_pgtable_ops.
190  */
191 void free_io_pgtable_ops(struct io_pgtable_ops *ops);
192 
193 
194 /*
195  * Internal structures for page table allocator implementations.
196  */
197 
198 /**
199  * struct io_pgtable - Internal structure describing a set of page tables.
200  *
201  * @fmt:    The page table format.
202  * @cookie: An opaque token provided by the IOMMU driver and passed back to
203  *          any callback routines.
204  * @cfg:    A copy of the page table configuration.
205  * @ops:    The page table operations in use for this set of page tables.
206  */
207 struct io_pgtable {
208 	enum io_pgtable_fmt	fmt;
209 	void			*cookie;
210 	struct io_pgtable_cfg	cfg;
211 	struct io_pgtable_ops	ops;
212 };
213 
214 #define io_pgtable_ops_to_pgtable(x) container_of((x), struct io_pgtable, ops)
215 
216 static inline void io_pgtable_tlb_flush_all(struct io_pgtable *iop)
217 {
218 	if (iop->cfg.tlb && iop->cfg.tlb->tlb_flush_all)
219 		iop->cfg.tlb->tlb_flush_all(iop->cookie);
220 }
221 
222 static inline void
223 io_pgtable_tlb_flush_walk(struct io_pgtable *iop, unsigned long iova,
224 			  size_t size, size_t granule)
225 {
226 	if (iop->cfg.tlb && iop->cfg.tlb->tlb_flush_walk)
227 		iop->cfg.tlb->tlb_flush_walk(iova, size, granule, iop->cookie);
228 }
229 
230 static inline void
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 && 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 extern struct io_pgtable_init_fns io_pgtable_amd_iommu_v1_init_fns;
258 extern struct io_pgtable_init_fns io_pgtable_apple_dart_init_fns;
259 
260 #endif /* __IO_PGTABLE_H */
261