tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#ifndef __IO_PGTABLE_H
2#define __IO_PGTABLE_H
3#include <linux/bitops.h>
4
5/*
6 * Public API for use by IOMMU drivers
7 */
8enum io_pgtable_fmt {
9 ARM_32_LPAE_S1,
10 ARM_32_LPAE_S2,
11 ARM_64_LPAE_S1,
12 ARM_64_LPAE_S2,
13 ARM_V7S,
14 IO_PGTABLE_NUM_FMTS,
15};
16
17/**
18 * struct iommu_gather_ops - IOMMU callbacks for TLB and page table management.
19 *
20 * @tlb_flush_all: Synchronously invalidate the entire TLB context.
21 * @tlb_add_flush: Queue up a TLB invalidation for a virtual address range.
22 * @tlb_sync: Ensure any queued TLB invalidation has taken effect, and
23 * any corresponding page table updates are visible to the
24 * IOMMU.
25 *
26 * Note that these can all be called in atomic context and must therefore
27 * not block.
28 */
29struct iommu_gather_ops {
30 void (*tlb_flush_all)(void *cookie);
31 void (*tlb_add_flush)(unsigned long iova, size_t size, size_t granule,
32 bool leaf, void *cookie);
33 void (*tlb_sync)(void *cookie);
34};
35
36/**
37 * struct io_pgtable_cfg - Configuration data for a set of page tables.
38 *
39 * @quirks: A bitmap of hardware quirks that require some special
40 * action by the low-level page table allocator.
41 * @pgsize_bitmap: A bitmap of page sizes supported by this set of page
42 * tables.
43 * @ias: Input address (iova) size, in bits.
44 * @oas: Output address (paddr) size, in bits.
45 * @tlb: TLB management callbacks for this set of tables.
46 * @iommu_dev: The device representing the DMA configuration for the
47 * page table walker.
48 */
49struct io_pgtable_cfg {
50 /*
51 * IO_PGTABLE_QUIRK_ARM_NS: (ARM formats) Set NS and NSTABLE bits in
52 * stage 1 PTEs, for hardware which insists on validating them
53 * even in non-secure state where they should normally be ignored.
54 *
55 * IO_PGTABLE_QUIRK_NO_PERMS: Ignore the IOMMU_READ, IOMMU_WRITE and
56 * IOMMU_NOEXEC flags and map everything with full access, for
57 * hardware which does not implement the permissions of a given
58 * format, and/or requires some format-specific default value.
59 *
60 * IO_PGTABLE_QUIRK_TLBI_ON_MAP: If the format forbids caching invalid
61 * (unmapped) entries but the hardware might do so anyway, perform
62 * TLB maintenance when mapping as well as when unmapping.
63 *
64 * IO_PGTABLE_QUIRK_ARM_MTK_4GB: (ARM v7s format) Set bit 9 in all
65 * PTEs, for Mediatek IOMMUs which treat it as a 33rd address bit
66 * when the SoC is in "4GB mode" and they can only access the high
67 * remap of DRAM (0x1_00000000 to 0x1_ffffffff).
68 */
69 #define IO_PGTABLE_QUIRK_ARM_NS BIT(0)
70 #define IO_PGTABLE_QUIRK_NO_PERMS BIT(1)
71 #define IO_PGTABLE_QUIRK_TLBI_ON_MAP BIT(2)
72 #define IO_PGTABLE_QUIRK_ARM_MTK_4GB BIT(3)
73 unsigned long quirks;
74 unsigned long pgsize_bitmap;
75 unsigned int ias;
76 unsigned int oas;
77 const struct iommu_gather_ops *tlb;
78 struct device *iommu_dev;
79
80 /* Low-level data specific to the table format */
81 union {
82 struct {
83 u64 ttbr[2];
84 u64 tcr;
85 u64 mair[2];
86 } arm_lpae_s1_cfg;
87
88 struct {
89 u64 vttbr;
90 u64 vtcr;
91 } arm_lpae_s2_cfg;
92
93 struct {
94 u32 ttbr[2];
95 u32 tcr;
96 u32 nmrr;
97 u32 prrr;
98 } arm_v7s_cfg;
99 };
100};
101
102/**
103 * struct io_pgtable_ops - Page table manipulation API for IOMMU drivers.
104 *
105 * @map: Map a physically contiguous memory region.
106 * @unmap: Unmap a physically contiguous memory region.
107 * @iova_to_phys: Translate iova to physical address.
108 *
109 * These functions map directly onto the iommu_ops member functions with
110 * the same names.
111 */
112struct io_pgtable_ops {
113 int (*map)(struct io_pgtable_ops *ops, unsigned long iova,
114 phys_addr_t paddr, size_t size, int prot);
115 int (*unmap)(struct io_pgtable_ops *ops, unsigned long iova,
116 size_t size);
117 phys_addr_t (*iova_to_phys)(struct io_pgtable_ops *ops,
118 unsigned long iova);
119};
120
121/**
122 * alloc_io_pgtable_ops() - Allocate a page table allocator for use by an IOMMU.
123 *
124 * @fmt: The page table format.
125 * @cfg: The page table configuration. This will be modified to represent
126 * the configuration actually provided by the allocator (e.g. the
127 * pgsize_bitmap may be restricted).
128 * @cookie: An opaque token provided by the IOMMU driver and passed back to
129 * the callback routines in cfg->tlb.
130 */
131struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
132 struct io_pgtable_cfg *cfg,
133 void *cookie);
134
135/**
136 * free_io_pgtable_ops() - Free an io_pgtable_ops structure. The caller
137 * *must* ensure that the page table is no longer
138 * live, but the TLB can be dirty.
139 *
140 * @ops: The ops returned from alloc_io_pgtable_ops.
141 */
142void free_io_pgtable_ops(struct io_pgtable_ops *ops);
143
144
145/*
146 * Internal structures for page table allocator implementations.
147 */
148
149/**
150 * struct io_pgtable - Internal structure describing a set of page tables.
151 *
152 * @fmt: The page table format.
153 * @cookie: An opaque token provided by the IOMMU driver and passed back to
154 * any callback routines.
155 * @tlb_sync_pending: Private flag for optimising out redundant syncs.
156 * @cfg: A copy of the page table configuration.
157 * @ops: The page table operations in use for this set of page tables.
158 */
159struct io_pgtable {
160 enum io_pgtable_fmt fmt;
161 void *cookie;
162 bool tlb_sync_pending;
163 struct io_pgtable_cfg cfg;
164 struct io_pgtable_ops ops;
165};
166
167#define io_pgtable_ops_to_pgtable(x) container_of((x), struct io_pgtable, ops)
168
169static inline void io_pgtable_tlb_flush_all(struct io_pgtable *iop)
170{
171 iop->cfg.tlb->tlb_flush_all(iop->cookie);
172 iop->tlb_sync_pending = true;
173}
174
175static inline void io_pgtable_tlb_add_flush(struct io_pgtable *iop,
176 unsigned long iova, size_t size, size_t granule, bool leaf)
177{
178 iop->cfg.tlb->tlb_add_flush(iova, size, granule, leaf, iop->cookie);
179 iop->tlb_sync_pending = true;
180}
181
182static inline void io_pgtable_tlb_sync(struct io_pgtable *iop)
183{
184 if (iop->tlb_sync_pending) {
185 iop->cfg.tlb->tlb_sync(iop->cookie);
186 iop->tlb_sync_pending = false;
187 }
188}
189
190/**
191 * struct io_pgtable_init_fns - Alloc/free a set of page tables for a
192 * particular format.
193 *
194 * @alloc: Allocate a set of page tables described by cfg.
195 * @free: Free the page tables associated with iop.
196 */
197struct io_pgtable_init_fns {
198 struct io_pgtable *(*alloc)(struct io_pgtable_cfg *cfg, void *cookie);
199 void (*free)(struct io_pgtable *iop);
200};
201
202extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns;
203extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns;
204extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns;
205extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns;
206extern struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns;
207
208#endif /* __IO_PGTABLE_H */