1// SPDX-License-Identifier: GPL-2.0
2/*
3 * arch/sh/kernel/machvec.c
4 *
5 * The SuperH machine vector setup handlers, yanked from setup.c
6 *
7 *  Copyright (C) 1999  Niibe Yutaka
8 *  Copyright (C) 2002 - 2007 Paul Mundt
9 */
10#include <linux/init.h>
11#include <linux/string.h>
12#include <asm/machvec.h>
13#include <asm/sections.h>
14#include <asm/addrspace.h>
15#include <asm/setup.h>
16#include <asm/io.h>
17#include <asm/irq.h>
18#include <asm/processor.h>
19
20#define MV_NAME_SIZE 32
21
22#define for_each_mv(mv) \
23	for ((mv) = (struct sh_machine_vector *)__machvec_start; \
24	     (mv) && (unsigned long)(mv) < (unsigned long)__machvec_end; \
25	     (mv)++)
26
27static struct sh_machine_vector * __init get_mv_byname(const char *name)
28{
29	struct sh_machine_vector *mv;
30
31	for_each_mv(mv)
32		if (strcasecmp(name, mv->mv_name) == 0)
33			return mv;
34
35	return NULL;
36}
37
38static unsigned int __initdata machvec_selected;
39
40static int __init early_parse_mv(char *from)
41{
42	char mv_name[MV_NAME_SIZE] = "";
43	char *mv_end;
44	char *mv_comma;
45	int mv_len;
46	struct sh_machine_vector *mvp;
47
48	mv_end = strchr(from, ' ');
49	if (mv_end == NULL)
50		mv_end = from + strlen(from);
51
52	mv_comma = strchr(from, ',');
53	mv_len = mv_end - from;
54	if (mv_len > (MV_NAME_SIZE-1))
55		mv_len = MV_NAME_SIZE-1;
56	memcpy(mv_name, from, mv_len);
57	mv_name[mv_len] = '\0';
58	from = mv_end;
59
60	machvec_selected = 1;
61
62	/* Boot with the generic vector */
63	if (strcmp(mv_name, "generic") == 0)
64		return 0;
65
66	mvp = get_mv_byname(mv_name);
67	if (unlikely(!mvp)) {
68		pr_info("Available vectors:\n\n\t'%s', ", sh_mv.mv_name);
69		for_each_mv(mvp)
70			pr_cont("'%s', ", mvp->mv_name);
71		pr_cont("\n\n");
72		panic("Failed to select machvec '%s' -- halting.\n",
73		      mv_name);
74	} else
75		sh_mv = *mvp;
76
77	return 0;
78}
79early_param("sh_mv", early_parse_mv);
80
81void __init sh_mv_setup(void)
82{
83	/*
84	 * Only overload the machvec if one hasn't been selected on
85	 * the command line with sh_mv=
86	 */
87	if (!machvec_selected) {
88		unsigned long machvec_size;
89
90		machvec_size = ((unsigned long)__machvec_end -
91				(unsigned long)__machvec_start);
92
93		/*
94		 * Sanity check for machvec section alignment. Ensure
95		 * __initmv hasn't been misused.
96		 */
97		if (machvec_size % sizeof(struct sh_machine_vector))
98			panic("machvec misaligned, invalid __initmv use?");
99
100		/*
101		 * If the machvec hasn't been preselected, use the first
102		 * vector (usually the only one) from .machvec.init.
103		 */
104		if (machvec_size >= sizeof(struct sh_machine_vector))
105			sh_mv = *(struct sh_machine_vector *)__machvec_start;
106	}
107
108	pr_notice("Booting machvec: %s\n", get_system_type());
109
110	/*
111	 * Manually walk the vec, fill in anything that the board hasn't yet
112	 * by hand, wrapping to the generic implementation.
113	 */
114#define mv_set(elem) do { \
115	if (!sh_mv.mv_##elem) \
116		sh_mv.mv_##elem = generic_##elem; \
117} while (0)
118
119	mv_set(irq_demux);
120	mv_set(mode_pins);
121	mv_set(mem_init);
122}
123