1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * Copyright (C) 2016 Imagination Technologies
4 * Author: Paul Burton <paul.burton@mips.com>
5 */
6
7 #ifndef __MIPS_ASM_MACHINE_H__
8 #define __MIPS_ASM_MACHINE_H__
9
10 #include <linux/libfdt.h>
11 #include <linux/of.h>
12
13 struct mips_machine {
14 const struct of_device_id *matches;
15 const void *fdt;
16 bool (*detect)(void);
17 const void *(*fixup_fdt)(const void *fdt, const void *match_data);
18 unsigned int (*measure_hpt_freq)(void);
19 };
20
21 extern long __mips_machines_start;
22 extern long __mips_machines_end;
23
24 #define MIPS_MACHINE(name) \
25 static const struct mips_machine __mips_mach_##name \
26 __used __section(.mips.machines.init)
27
28 #define for_each_mips_machine(mach) \
29 for ((mach) = (struct mips_machine *)&__mips_machines_start; \
30 (mach) < (struct mips_machine *)&__mips_machines_end; \
31 (mach)++)
32
33 /**
34 * mips_machine_is_compatible() - check if a machine is compatible with an FDT
35 * @mach: the machine struct to check
36 * @fdt: the FDT to check for compatibility with
37 *
38 * Check whether the given machine @mach is compatible with the given flattened
39 * device tree @fdt, based upon the compatibility property of the root node.
40 *
41 * Return: the device id matched if any, else NULL
42 */
43 static inline const struct of_device_id *
44 mips_machine_is_compatible(const struct mips_machine *mach, const void *fdt)
45 {
46 const struct of_device_id *match;
47
48 if (!mach->matches)
49 return NULL;
50
51 for (match = mach->matches; match->compatible[0]; match++) {
52 if (fdt_node_check_compatible(fdt, 0, match->compatible) == 0)
53 return match;
54 }
55
56 return NULL;
57 }
58
59 /**
60 * struct mips_fdt_fixup - Describe a fixup to apply to an FDT
61 * @apply: applies the fixup to @fdt, returns zero on success else -errno
62 * @description: a short description of the fixup
63 *
64 * Describes a fixup applied to an FDT blob by the @apply function. The
65 * @description field provides a short description of the fixup intended for
66 * use in error messages if the @apply function returns non-zero.
67 */
68 struct mips_fdt_fixup {
69 int (*apply)(void *fdt);
70 const char *description;
71 };
72
73 /**
74 * apply_mips_fdt_fixups() - apply fixups to an FDT blob
75 * @fdt_out: buffer in which to place the fixed-up FDT
76 * @fdt_out_size: the size of the @fdt_out buffer
77 * @fdt_in: the FDT blob
78 * @fixups: pointer to an array of fixups to be applied
79 *
80 * Loop through the array of fixups pointed to by @fixups, calling the apply
81 * function on each until either one returns an error or we reach the end of
82 * the list as indicated by an entry with a NULL apply field.
83 *
84 * Return: zero on success, else -errno
85 */
86 extern int __init apply_mips_fdt_fixups(void *fdt_out, size_t fdt_out_size,
87 const void *fdt_in,
88 const struct mips_fdt_fixup *fixups);
89
90 #endif /* __MIPS_ASM_MACHINE_H__ */