xref: /openbmc/linux/arch/sh/kernel/machvec.c (revision f3539c12)
1 /*
2  * arch/sh/kernel/machvec.c
3  *
4  * The SuperH machine vector setup handlers, yanked from setup.c
5  *
6  *  Copyright (C) 1999  Niibe Yutaka
7  *  Copyright (C) 2002 - 2007 Paul Mundt
8  *
9  * This file is subject to the terms and conditions of the GNU General Public
10  * License.  See the file "COPYING" in the main directory of this archive
11  * for more details.
12  */
13 #include <linux/init.h>
14 #include <linux/string.h>
15 #include <asm/machvec.h>
16 #include <asm/sections.h>
17 #include <asm/addrspace.h>
18 #include <asm/setup.h>
19 #include <asm/io.h>
20 #include <asm/irq.h>
21 
22 #define MV_NAME_SIZE 32
23 
24 #define for_each_mv(mv) \
25 	for ((mv) = (struct sh_machine_vector *)&__machvec_start; \
26 	     (mv) && (unsigned long)(mv) < (unsigned long)&__machvec_end; \
27 	     (mv)++)
28 
29 static struct sh_machine_vector * __init get_mv_byname(const char *name)
30 {
31 	struct sh_machine_vector *mv;
32 
33 	for_each_mv(mv)
34 		if (strcasecmp(name, mv->mv_name) == 0)
35 			return mv;
36 
37 	return NULL;
38 }
39 
40 static unsigned int __initdata machvec_selected;
41 
42 static int __init early_parse_mv(char *from)
43 {
44 	char mv_name[MV_NAME_SIZE] = "";
45 	char *mv_end;
46 	char *mv_comma;
47 	int mv_len;
48 	struct sh_machine_vector *mvp;
49 
50 	mv_end = strchr(from, ' ');
51 	if (mv_end == NULL)
52 		mv_end = from + strlen(from);
53 
54 	mv_comma = strchr(from, ',');
55 	mv_len = mv_end - from;
56 	if (mv_len > (MV_NAME_SIZE-1))
57 		mv_len = MV_NAME_SIZE-1;
58 	memcpy(mv_name, from, mv_len);
59 	mv_name[mv_len] = '\0';
60 	from = mv_end;
61 
62 	machvec_selected = 1;
63 
64 	/* Boot with the generic vector */
65 	if (strcmp(mv_name, "generic") == 0)
66 		return 0;
67 
68 	mvp = get_mv_byname(mv_name);
69 	if (unlikely(!mvp)) {
70 		printk("Available vectors:\n\n\t'%s', ", sh_mv.mv_name);
71 		for_each_mv(mvp)
72 			printk("'%s', ", mvp->mv_name);
73 		printk("\n\n");
74 		panic("Failed to select machvec '%s' -- halting.\n",
75 		      mv_name);
76 	} else
77 		sh_mv = *mvp;
78 
79 	return 0;
80 }
81 early_param("sh_mv", early_parse_mv);
82 
83 void __init sh_mv_setup(void)
84 {
85 	/*
86 	 * Only overload the machvec if one hasn't been selected on
87 	 * the command line with sh_mv=
88 	 */
89 	if (!machvec_selected) {
90 		unsigned long machvec_size;
91 
92 		machvec_size = ((unsigned long)&__machvec_end -
93 				(unsigned long)&__machvec_start);
94 
95 		/*
96 		 * Sanity check for machvec section alignment. Ensure
97 		 * __initmv hasn't been misused.
98 		 */
99 		if (machvec_size % sizeof(struct sh_machine_vector))
100 			panic("machvec misaligned, invalid __initmv use?");
101 
102 		/*
103 		 * If the machvec hasn't been preselected, use the first
104 		 * vector (usually the only one) from .machvec.init.
105 		 */
106 		if (machvec_size >= sizeof(struct sh_machine_vector))
107 			sh_mv = *(struct sh_machine_vector *)&__machvec_start;
108 	}
109 
110 	printk(KERN_NOTICE "Booting machvec: %s\n", get_system_type());
111 
112 	/*
113 	 * Manually walk the vec, fill in anything that the board hasn't yet
114 	 * by hand, wrapping to the generic implementation.
115 	 */
116 #define mv_set(elem) do { \
117 	if (!sh_mv.mv_##elem) \
118 		sh_mv.mv_##elem = generic_##elem; \
119 } while (0)
120 
121 	mv_set(irq_demux);
122 	mv_set(mode_pins);
123 	mv_set(mem_init);
124 }
125