arch/sh/kernel/machvec.c

   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
  27 static 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
  38 static unsigned int __initdata machvec_selected;
  39
  40 static 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 }
  79 early_param("sh_mv", early_parse_mv);
  80
  81 void __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 }