LXR linux/arch/m68k/sun3x/prom.c

   1// SPDX-License-Identifier: GPL-2.0
   2/* Prom access routines for the sun3x */
   3
   4#include <linux/types.h>
   5#include <linux/kernel.h>
   6#include <linux/tty.h>
   7#include <linux/console.h>
   8#include <linux/init.h>
   9#include <linux/mm.h>
  10#include <linux/string.h>
  11
  12#include <asm/page.h>
  13#include <asm/setup.h>
  14#include <asm/traps.h>
  15#include <asm/sun3xprom.h>
  16#include <asm/idprom.h>
  17#include <asm/sun3ints.h>
  18#include <asm/openprom.h>
  19#include <asm/machines.h>
  20
  21void (*sun3x_putchar)(int);
  22int (*sun3x_getchar)(void);
  23int (*sun3x_mayget)(void);
  24int (*sun3x_mayput)(int);
  25void (*sun3x_prom_reboot)(void);
  26e_vector sun3x_prom_abort;
  27struct linux_romvec *romvec;
  28
  29/* prom vector table */
  30e_vector *sun3x_prom_vbr;
  31
  32/* Handle returning to the prom */
  33void sun3x_halt(void)
  34{
  35        unsigned long flags;
  36
  37        /* Disable interrupts while we mess with things */
  38        local_irq_save(flags);
  39
  40        /* Restore prom vbr */
  41        asm volatile ("movec %0,%%vbr" : : "r" ((void*)sun3x_prom_vbr));
  42
  43        /* Restore prom NMI clock */
  44//      sun3x_disable_intreg(5);
  45        sun3_enable_irq(7);
  46
  47        /* Let 'er rip */
  48        asm volatile ("trap #14");
  49
  50        /* Restore everything */
  51        sun3_disable_irq(7);
  52        sun3_enable_irq(5);
  53
  54        asm volatile ("movec %0,%%vbr" : : "r" ((void*)vectors));
  55        local_irq_restore(flags);
  56}
  57
  58void sun3x_reboot(void)
  59{
  60        /* This never returns, don't bother saving things */
  61        local_irq_disable();
  62
  63        /* Restore prom vbr */
  64        asm volatile ("movec %0,%%vbr" : : "r" ((void*)sun3x_prom_vbr));
  65
  66        /* Restore prom NMI clock */
  67        sun3_disable_irq(5);
  68        sun3_enable_irq(7);
  69
  70        /* Let 'er rip */
  71        (*romvec->pv_reboot)("vmlinux");
  72}
  73
  74static void sun3x_prom_write(struct console *co, const char *s,
  75                             unsigned int count)
  76{
  77        while (count--) {
  78                if (*s == '\n')
  79                        sun3x_putchar('\r');
  80                sun3x_putchar(*s++);
  81        }
  82}
  83
  84/* debug console - write-only */
  85
  86static struct console sun3x_debug = {
  87        .name   = "debug",
  88        .write  = sun3x_prom_write,
  89        .flags  = CON_PRINTBUFFER,
  90        .index  = -1,
  91};
  92
  93void __init sun3x_prom_init(void)
  94{
  95        /* Read the vector table */
  96
  97        sun3x_putchar = *(void (**)(int)) (SUN3X_P_PUTCHAR);
  98        sun3x_getchar = *(int (**)(void)) (SUN3X_P_GETCHAR);
  99        sun3x_mayget = *(int (**)(void))  (SUN3X_P_MAYGET);
 100        sun3x_mayput = *(int (**)(int))   (SUN3X_P_MAYPUT);
 101        sun3x_prom_reboot = *(void (**)(void)) (SUN3X_P_REBOOT);
 102        sun3x_prom_abort = *(e_vector *)  (SUN3X_P_ABORT);
 103        romvec = (struct linux_romvec *)SUN3X_PROM_BASE;
 104
 105        idprom_init();
 106
 107        if (!((idprom->id_machtype & SM_ARCH_MASK) == SM_SUN3X)) {
 108                pr_warn("Machine reports strange type %02x\n",
 109                        idprom->id_machtype);
 110                pr_warn("Pretending it's a 3/80, but very afraid...\n");
 111                idprom->id_machtype = SM_SUN3X | SM_3_80;
 112        }
 113
 114        /* point trap #14 at abort.
 115         * XXX this is futile since we restore the vbr first - oops
 116         */
 117        vectors[VEC_TRAP14] = sun3x_prom_abort;
 118}
 119
 120static int __init sun3x_debug_setup(char *arg)
 121{
 122        /* If debug=prom was specified, start the debug console */
 123        if (MACH_IS_SUN3X && !strcmp(arg, "prom"))
 124                register_console(&sun3x_debug);
 125        return 0;
 126}
 127
 128early_param("debug", sun3x_debug_setup);
 129
 130/* some prom functions to export */
 131int prom_getintdefault(int node, char *property, int deflt)
 132{
 133        return deflt;
 134}
 135
 136int prom_getbool (int node, char *prop)
 137{
 138        return 1;
 139}
 140
 141void prom_printf(char *fmt, ...)
 142{
 143}
 144
 145void prom_halt (void)
 146{
 147        sun3x_halt();
 148}
 149
 150/* Get the idprom and stuff it into buffer 'idbuf'.  Returns the
 151 * format type.  'num_bytes' is the number of bytes that your idbuf
 152 * has space for.  Returns 0xff on error.
 153 */
 154unsigned char
 155prom_get_idprom(char *idbuf, int num_bytes)
 156{
 157        int i;
 158
 159        /* make a copy of the idprom structure */
 160        for (i = 0; i < num_bytes; i++)
 161                idbuf[i] = ((char *)SUN3X_IDPROM)[i];
 162
 163        return idbuf[0];
 164}
 165