xref: /openbmc/linux/drivers/iommu/io-pgtable.c (revision 4a6a676f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Generic page table allocator for IOMMUs.
4  *
5  * Copyright (C) 2014 ARM Limited
6  *
7  * Author: Will Deacon <will.deacon@arm.com>
8  */
9 
10 #include <linux/bug.h>
11 #include <linux/io-pgtable.h>
12 #include <linux/kernel.h>
13 #include <linux/types.h>
14 
15 static const struct io_pgtable_init_fns *
16 io_pgtable_init_table[IO_PGTABLE_NUM_FMTS] = {
17 #ifdef CONFIG_IOMMU_IO_PGTABLE_LPAE
18 	[ARM_32_LPAE_S1] = &io_pgtable_arm_32_lpae_s1_init_fns,
19 	[ARM_32_LPAE_S2] = &io_pgtable_arm_32_lpae_s2_init_fns,
20 	[ARM_64_LPAE_S1] = &io_pgtable_arm_64_lpae_s1_init_fns,
21 	[ARM_64_LPAE_S2] = &io_pgtable_arm_64_lpae_s2_init_fns,
22 	[ARM_MALI_LPAE] = &io_pgtable_arm_mali_lpae_init_fns,
23 #endif
24 #ifdef CONFIG_IOMMU_IO_PGTABLE_DART
25 	[APPLE_DART] = &io_pgtable_apple_dart_init_fns,
26 	[APPLE_DART2] = &io_pgtable_apple_dart_init_fns,
27 #endif
28 #ifdef CONFIG_IOMMU_IO_PGTABLE_ARMV7S
29 	[ARM_V7S] = &io_pgtable_arm_v7s_init_fns,
30 #endif
31 #ifdef CONFIG_AMD_IOMMU
32 	[AMD_IOMMU_V1] = &io_pgtable_amd_iommu_v1_init_fns,
33 	[AMD_IOMMU_V2] = &io_pgtable_amd_iommu_v2_init_fns,
34 #endif
35 };
36 
37 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
38 					    struct io_pgtable_cfg *cfg,
39 					    void *cookie)
40 {
41 	struct io_pgtable *iop;
42 	const struct io_pgtable_init_fns *fns;
43 
44 	if (fmt >= IO_PGTABLE_NUM_FMTS)
45 		return NULL;
46 
47 	fns = io_pgtable_init_table[fmt];
48 	if (!fns)
49 		return NULL;
50 
51 	iop = fns->alloc(cfg, cookie);
52 	if (!iop)
53 		return NULL;
54 
55 	iop->fmt	= fmt;
56 	iop->cookie	= cookie;
57 	iop->cfg	= *cfg;
58 
59 	return &iop->ops;
60 }
61 EXPORT_SYMBOL_GPL(alloc_io_pgtable_ops);
62 
63 /*
64  * It is the IOMMU driver's responsibility to ensure that the page table
65  * is no longer accessible to the walker by this point.
66  */
67 void free_io_pgtable_ops(struct io_pgtable_ops *ops)
68 {
69 	struct io_pgtable *iop;
70 
71 	if (!ops)
72 		return;
73 
74 	iop = io_pgtable_ops_to_pgtable(ops);
75 	io_pgtable_tlb_flush_all(iop);
76 	io_pgtable_init_table[iop->fmt]->free(iop);
77 }
78 EXPORT_SYMBOL_GPL(free_io_pgtable_ops);
79