xref: /openbmc/linux/drivers/iommu/io-pgtable.c (revision aaac38f6)
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 	[APPLE_DART] = &io_pgtable_apple_dart_init_fns,
24 #endif
25 #ifdef CONFIG_IOMMU_IO_PGTABLE_ARMV7S
26 	[ARM_V7S] = &io_pgtable_arm_v7s_init_fns,
27 #endif
28 #ifdef CONFIG_AMD_IOMMU
29 	[AMD_IOMMU_V1] = &io_pgtable_amd_iommu_v1_init_fns,
30 	[AMD_IOMMU_V2] = &io_pgtable_amd_iommu_v2_init_fns,
31 #endif
32 };
33 
34 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
35 					    struct io_pgtable_cfg *cfg,
36 					    void *cookie)
37 {
38 	struct io_pgtable *iop;
39 	const struct io_pgtable_init_fns *fns;
40 
41 	if (fmt >= IO_PGTABLE_NUM_FMTS)
42 		return NULL;
43 
44 	fns = io_pgtable_init_table[fmt];
45 	if (!fns)
46 		return NULL;
47 
48 	iop = fns->alloc(cfg, cookie);
49 	if (!iop)
50 		return NULL;
51 
52 	iop->fmt	= fmt;
53 	iop->cookie	= cookie;
54 	iop->cfg	= *cfg;
55 
56 	return &iop->ops;
57 }
58 EXPORT_SYMBOL_GPL(alloc_io_pgtable_ops);
59 
60 /*
61  * It is the IOMMU driver's responsibility to ensure that the page table
62  * is no longer accessible to the walker by this point.
63  */
64 void free_io_pgtable_ops(struct io_pgtable_ops *ops)
65 {
66 	struct io_pgtable *iop;
67 
68 	if (!ops)
69 		return;
70 
71 	iop = io_pgtable_ops_to_pgtable(ops);
72 	io_pgtable_tlb_flush_all(iop);
73 	io_pgtable_init_table[iop->fmt]->free(iop);
74 }
75 EXPORT_SYMBOL_GPL(free_io_pgtable_ops);
76