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/pgtable.h>
  14#include <asm/setup.h>
  15#include <asm/traps.h>
  16#include <asm/sun3xprom.h>
  17#include <asm/idprom.h>
  18#include <asm/segment.h>
  19#include <asm/sun3ints.h>
  20#include <asm/openprom.h>
  21#include <asm/machines.h>
  22
  23void (*sun3x_putchar)(int);
  24int (*sun3x_getchar)(void);
  25int (*sun3x_mayget)(void);
  26int (*sun3x_mayput)(int);
  27void (*sun3x_prom_reboot)(void);
  28e_vector sun3x_prom_abort;
  29struct linux_romvec *romvec;
  30
  31/* prom vector table */
  32e_vector *sun3x_prom_vbr;
  33
  34/* Handle returning to the prom */
  35void sun3x_halt(void)
  36{
  37        unsigned long flags;
  38
  39        /* Disable interrupts while we mess with things */
  40        local_irq_save(flags);
  41
  42        /* Restore prom vbr */
  43        asm volatile ("movec %0,%%vbr" : : "r" ((void*)sun3x_prom_vbr));
  44
  45        /* Restore prom NMI clock */
  46//      sun3x_disable_intreg(5);
  47        sun3_enable_irq(7);
  48
  49        /* Let 'er rip */
  50        asm volatile ("trap #14");
  51
  52        /* Restore everything */
  53        sun3_disable_irq(7);
  54        sun3_enable_irq(5);
  55
  56        asm volatile ("movec %0,%%vbr" : : "r" ((void*)vectors));
  57        local_irq_restore(flags);
  58}
  59
  60void sun3x_reboot(void)
  61{
  62        /* This never returns, don't bother saving things */
  63        local_irq_disable();
  64
  65        /* Restore prom vbr */
  66        asm volatile ("movec %0,%%vbr" : : "r" ((void*)sun3x_prom_vbr));
  67
  68        /* Restore prom NMI clock */
  69        sun3_disable_irq(5);
  70        sun3_enable_irq(7);
  71
  72        /* Let 'er rip */
  73        (*romvec->pv_reboot)("vmlinux");
  74}
  75
  76static void sun3x_prom_write(struct console *co, const char *s,
  77                             unsigned int count)
  78{
  79        while (count--) {
  80                if (*s == '\n')
  81                        sun3x_putchar('\r');
  82                sun3x_putchar(*s++);
  83        }
  84}
  85
  86/* debug console - write-only */
  87
  88static struct console sun3x_debug = {
  89        .name   = "debug",
  90        .write  = sun3x_prom_write,
  91        .flags  = CON_PRINTBUFFER,
  92        .index  = -1,
  93};
  94
  95void __init sun3x_prom_init(void)
  96{
  97        /* Read the vector table */
  98
  99        sun3x_putchar = *(void (**)(int)) (SUN3X_P_PUTCHAR);
 100        sun3x_getchar = *(int (**)(void)) (SUN3X_P_GETCHAR);
 101        sun3x_mayget = *(int (**)(void))  (SUN3X_P_MAYGET);
 102        sun3x_mayput = *(int (**)(int))   (SUN3X_P_MAYPUT);
 103        sun3x_prom_reboot = *(void (**)(void)) (SUN3X_P_REBOOT);
 104        sun3x_prom_abort = *(e_vector *)  (SUN3X_P_ABORT);
 105        romvec = (struct linux_romvec *)SUN3X_PROM_BASE;
 106
 107        idprom_init();
 108
 109        if (!((idprom->id_machtype & SM_ARCH_MASK) == SM_SUN3X)) {
 110                pr_warn("Machine reports strange type %02x\n",
 111                        idprom->id_machtype);
 112                pr_warn("Pretending it's a 3/80, but very afraid...\n");
 113                idprom->id_machtype = SM_SUN3X | SM_3_80;
 114        }
 115
 116        /* point trap #14 at abort.
 117         * XXX this is futile since we restore the vbr first - oops
 118         */
 119        vectors[VEC_TRAP14] = sun3x_prom_abort;
 120}
 121
 122static int __init sun3x_debug_setup(char *arg)
 123{
 124        /* If debug=prom was specified, start the debug console */
 125        if (MACH_IS_SUN3X && !strcmp(arg, "prom"))
 126                register_console(&sun3x_debug);
 127        return 0;
 128}
 129
 130early_param("debug", sun3x_debug_setup);
 131
 132/* some prom functions to export */
 133int prom_getintdefault(int node, char *property, int deflt)
 134{
 135        return deflt;
 136}
 137
 138int prom_getbool (int node, char *prop)
 139{
 140        return 1;
 141}
 142
 143void prom_printf(char *fmt, ...)
 144{
 145}
 146
 147void prom_halt (void)
 148{
 149        sun3x_halt();
 150}
 151
 152/* Get the idprom and stuff it into buffer 'idbuf'.  Returns the
 153 * format type.  'num_bytes' is the number of bytes that your idbuf
 154 * has space for.  Returns 0xff on error.
 155 */
 156unsigned char
 157prom_get_idprom(char *idbuf, int num_bytes)
 158{
 159        int i;
 160
 161        /* make a copy of the idprom structure */
 162        for (i = 0; i < num_bytes; i++)
 163                idbuf[i] = ((char *)SUN3X_IDPROM)[i];
 164
 165        return idbuf[0];
 166}
 167