xref: /linux/include/linux/io-pgtable.h (revision 02680c23d7b3febe45ea3d4f9818c2b2dc89020a)
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 	IO_PGTABLE_NUM_FMTS,
20 };
21 
22 /**
23  * struct iommu_flush_ops - IOMMU callbacks for TLB and page table management.
24  *
25  * @tlb_flush_all:  Synchronously invalidate the entire TLB context.
26  * @tlb_flush_walk: Synchronously invalidate all intermediate TLB state
27  *                  (sometimes referred to as the "walk cache") for a virtual
28  *                  address range.
29  * @tlb_add_page:   Optional callback to queue up leaf TLB invalidation for a
30  *                  single page.  IOMMUs that cannot batch TLB invalidation
31  *                  operations efficiently will typically issue them here, but
32  *                  others may decide to update the iommu_iotlb_gather structure
33  *                  and defer the invalidation until iommu_iotlb_sync() instead.
34  *
35  * Note that these can all be called in atomic context and must therefore
36  * not block.
37  */
38 struct iommu_flush_ops {
39 	void (*tlb_flush_all)(void *cookie);
40 	void (*tlb_flush_walk)(unsigned long iova, size_t size, size_t granule,
41 			       void *cookie);
42 	void (*tlb_add_page)(struct iommu_iotlb_gather *gather,
43 			     unsigned long iova, size_t granule, void *cookie);
44 };
45 
46 /**
47  * struct io_pgtable_cfg - Configuration data for a set of page tables.
48  *
49  * @quirks:        A bitmap of hardware quirks that require some special
50  *                 action by the low-level page table allocator.
51  * @pgsize_bitmap: A bitmap of page sizes supported by this set of page
52  *                 tables.
53  * @ias:           Input address (iova) size, in bits.
54  * @oas:           Output address (paddr) size, in bits.
55  * @coherent_walk  A flag to indicate whether or not page table walks made
56  *                 by the IOMMU are coherent with the CPU caches.
57  * @tlb:           TLB management callbacks for this set of tables.
58  * @iommu_dev:     The device representing the DMA configuration for the
59  *                 page table walker.
60  */
61 struct io_pgtable_cfg {
62 	/*
63 	 * IO_PGTABLE_QUIRK_ARM_NS: (ARM formats) Set NS and NSTABLE bits in
64 	 *	stage 1 PTEs, for hardware which insists on validating them
65 	 *	even in	non-secure state where they should normally be ignored.
66 	 *
67 	 * IO_PGTABLE_QUIRK_NO_PERMS: Ignore the IOMMU_READ, IOMMU_WRITE and
68 	 *	IOMMU_NOEXEC flags and map everything with full access, for
69 	 *	hardware which does not implement the permissions of a given
70 	 *	format, and/or requires some format-specific default value.
71 	 *
72 	 * IO_PGTABLE_QUIRK_ARM_MTK_EXT: (ARM v7s format) MediaTek IOMMUs extend
73 	 *	to support up to 35 bits PA where the bit32, bit33 and bit34 are
74 	 *	encoded in the bit9, bit4 and bit5 of the PTE respectively.
75 	 *
76 	 * IO_PGTABLE_QUIRK_NON_STRICT: Skip issuing synchronous leaf TLBIs
77 	 *	on unmap, for DMA domains using the flush queue mechanism for
78 	 *	delayed invalidation.
79 	 *
80 	 * IO_PGTABLE_QUIRK_ARM_TTBR1: (ARM LPAE format) Configure the table
81 	 *	for use in the upper half of a split address space.
82 	 *
83 	 * IO_PGTABLE_QUIRK_ARM_OUTER_WBWA: Override the outer-cacheability
84 	 *	attributes set in the TCR for a non-coherent page-table walker.
85 	 */
86 	#define IO_PGTABLE_QUIRK_ARM_NS		BIT(0)
87 	#define IO_PGTABLE_QUIRK_NO_PERMS	BIT(1)
88 	#define IO_PGTABLE_QUIRK_ARM_MTK_EXT	BIT(3)
89 	#define IO_PGTABLE_QUIRK_NON_STRICT	BIT(4)
90 	#define IO_PGTABLE_QUIRK_ARM_TTBR1	BIT(5)
91 	#define IO_PGTABLE_QUIRK_ARM_OUTER_WBWA	BIT(6)
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;
104 			struct {
105 				u32	ips:3;
106 				u32	tg:2;
107 				u32	sh:2;
108 				u32	orgn:2;
109 				u32	irgn:2;
110 				u32	tsz:6;
111 			}	tcr;
112 			u64	mair;
113 		} arm_lpae_s1_cfg;
114 
115 		struct {
116 			u64	vttbr;
117 			struct {
118 				u32	ps:3;
119 				u32	tg:2;
120 				u32	sh:2;
121 				u32	orgn:2;
122 				u32	irgn:2;
123 				u32	sl:2;
124 				u32	tsz:6;
125 			}	vtcr;
126 		} arm_lpae_s2_cfg;
127 
128 		struct {
129 			u32	ttbr;
130 			u32	tcr;
131 			u32	nmrr;
132 			u32	prrr;
133 		} arm_v7s_cfg;
134 
135 		struct {
136 			u64	transtab;
137 			u64	memattr;
138 		} arm_mali_lpae_cfg;
139 	};
140 };
141 
142 /**
143  * struct io_pgtable_ops - Page table manipulation API for IOMMU drivers.
144  *
145  * @map:          Map a physically contiguous memory region.
146  * @unmap:        Unmap a physically contiguous memory region.
147  * @iova_to_phys: Translate iova to physical address.
148  *
149  * These functions map directly onto the iommu_ops member functions with
150  * the same names.
151  */
152 struct io_pgtable_ops {
153 	int (*map)(struct io_pgtable_ops *ops, unsigned long iova,
154 		   phys_addr_t paddr, size_t size, int prot, gfp_t gfp);
155 	size_t (*unmap)(struct io_pgtable_ops *ops, unsigned long iova,
156 			size_t size, struct iommu_iotlb_gather *gather);
157 	phys_addr_t (*iova_to_phys)(struct io_pgtable_ops *ops,
158 				    unsigned long iova);
159 };
160 
161 /**
162  * alloc_io_pgtable_ops() - Allocate a page table allocator for use by an IOMMU.
163  *
164  * @fmt:    The page table format.
165  * @cfg:    The page table configuration. This will be modified to represent
166  *          the configuration actually provided by the allocator (e.g. the
167  *          pgsize_bitmap may be restricted).
168  * @cookie: An opaque token provided by the IOMMU driver and passed back to
169  *          the callback routines in cfg->tlb.
170  */
171 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
172 					    struct io_pgtable_cfg *cfg,
173 					    void *cookie);
174 
175 /**
176  * free_io_pgtable_ops() - Free an io_pgtable_ops structure. The caller
177  *                         *must* ensure that the page table is no longer
178  *                         live, but the TLB can be dirty.
179  *
180  * @ops: The ops returned from alloc_io_pgtable_ops.
181  */
182 void free_io_pgtable_ops(struct io_pgtable_ops *ops);
183 
184 
185 /*
186  * Internal structures for page table allocator implementations.
187  */
188 
189 /**
190  * struct io_pgtable - Internal structure describing a set of page tables.
191  *
192  * @fmt:    The page table format.
193  * @cookie: An opaque token provided by the IOMMU driver and passed back to
194  *          any callback routines.
195  * @cfg:    A copy of the page table configuration.
196  * @ops:    The page table operations in use for this set of page tables.
197  */
198 struct io_pgtable {
199 	enum io_pgtable_fmt	fmt;
200 	void			*cookie;
201 	struct io_pgtable_cfg	cfg;
202 	struct io_pgtable_ops	ops;
203 };
204 
205 #define io_pgtable_ops_to_pgtable(x) container_of((x), struct io_pgtable, ops)
206 
207 static inline void io_pgtable_tlb_flush_all(struct io_pgtable *iop)
208 {
209 	if (iop->cfg.tlb && iop->cfg.tlb->tlb_flush_all)
210 		iop->cfg.tlb->tlb_flush_all(iop->cookie);
211 }
212 
213 static inline void
214 io_pgtable_tlb_flush_walk(struct io_pgtable *iop, unsigned long iova,
215 			  size_t size, size_t granule)
216 {
217 	if (iop->cfg.tlb && iop->cfg.tlb->tlb_flush_walk)
218 		iop->cfg.tlb->tlb_flush_walk(iova, size, granule, iop->cookie);
219 }
220 
221 static inline void
222 io_pgtable_tlb_add_page(struct io_pgtable *iop,
223 			struct iommu_iotlb_gather * gather, unsigned long iova,
224 			size_t granule)
225 {
226 	if (iop->cfg.tlb && iop->cfg.tlb->tlb_add_page)
227 		iop->cfg.tlb->tlb_add_page(gather, iova, granule, iop->cookie);
228 }
229 
230 /**
231  * struct io_pgtable_init_fns - Alloc/free a set of page tables for a
232  *                              particular format.
233  *
234  * @alloc: Allocate a set of page tables described by cfg.
235  * @free:  Free the page tables associated with iop.
236  */
237 struct io_pgtable_init_fns {
238 	struct io_pgtable *(*alloc)(struct io_pgtable_cfg *cfg, void *cookie);
239 	void (*free)(struct io_pgtable *iop);
240 };
241 
242 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns;
243 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns;
244 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns;
245 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns;
246 extern struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns;
247 extern struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns;
248 extern struct io_pgtable_init_fns io_pgtable_amd_iommu_v1_init_fns;
249 
250 #endif /* __IO_PGTABLE_H */
251