root/arch/mips/dec/prom/init.c
// SPDX-License-Identifier: GPL-2.0
/*
 * init.c: PROM library initialisation code.
 *
 * Copyright (C) 1998 Harald Koerfgen
 * Copyright (C) 2002, 2004  Maciej W. Rozycki
 */
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/linkage.h>
#include <linux/smp.h>
#include <linux/string.h>
#include <linux/types.h>

#include <asm/bootinfo.h>
#include <asm/cpu.h>
#include <asm/cpu-type.h>
#include <asm/processor.h>

#include <asm/dec/prom.h>


int (*__rex_bootinit)(void);
int (*__rex_bootread)(void);
int (*__rex_getbitmap)(memmap *);
unsigned long *(*__rex_slot_address)(int);
void *(*__rex_gettcinfo)(void);
int (*__rex_getsysid)(void);
void (*__rex_clear_cache)(void);

int (*__prom_getchar)(void);
char *(*__prom_getenv)(char *);
int (*__prom_printf)(char *, ...);

int (*__pmax_open)(char*, int);
int (*__pmax_lseek)(int, long, int);
int (*__pmax_read)(int, void *, int);
int (*__pmax_close)(int);


/*
 * Detect which PROM the DECSTATION has, and set the callback vectors
 * appropriately.
 */
static void __init which_prom(s32 magic, s32 *prom_vec)
{
        /*
         * No sign of the REX PROM's magic number means we assume a non-REX
         * machine (i.e. we're on a DS2100/3100, DS5100 or DS5000/2xx)
         */
        if (prom_is_rex(magic)) {
                /*
                 * Set up prom abstraction structure with REX entry points.
                 */
                __rex_bootinit =
                        (void *)(long)*(prom_vec + REX_PROM_BOOTINIT);
                __rex_bootread =
                        (void *)(long)*(prom_vec + REX_PROM_BOOTREAD);
                __rex_getbitmap =
                        (void *)(long)*(prom_vec + REX_PROM_GETBITMAP);
                __prom_getchar =
                        (void *)(long)*(prom_vec + REX_PROM_GETCHAR);
                __prom_getenv =
                        (void *)(long)*(prom_vec + REX_PROM_GETENV);
                __rex_getsysid =
                        (void *)(long)*(prom_vec + REX_PROM_GETSYSID);
                __rex_gettcinfo =
                        (void *)(long)*(prom_vec + REX_PROM_GETTCINFO);
                __prom_printf =
                        (void *)(long)*(prom_vec + REX_PROM_PRINTF);
                __rex_slot_address =
                        (void *)(long)*(prom_vec + REX_PROM_SLOTADDR);
                __rex_clear_cache =
                        (void *)(long)*(prom_vec + REX_PROM_CLEARCACHE);
        } else {
                /*
                 * Set up prom abstraction structure with non-REX entry points.
                 */
                __prom_getchar = (void *)PMAX_PROM_GETCHAR;
                __prom_getenv = (void *)PMAX_PROM_GETENV;
                __prom_printf = (void *)PMAX_PROM_PRINTF;
                __pmax_open = (void *)PMAX_PROM_OPEN;
                __pmax_lseek = (void *)PMAX_PROM_LSEEK;
                __pmax_read = (void *)PMAX_PROM_READ;
                __pmax_close = (void *)PMAX_PROM_CLOSE;
        }
}

void __init prom_init(void)
{
        extern void dec_machine_halt(void);
        static const char cpu_msg[] __initconst =
                "Sorry, this kernel is compiled for a wrong CPU type!\n";
        s32 argc = fw_arg0;
        s32 *argv = (void *)fw_arg1;
        u32 magic = fw_arg2;
        s32 *prom_vec = (void *)fw_arg3;

        /*
         * Determine which PROM we have
         * (and therefore which machine we're on!)
         */
        which_prom(magic, prom_vec);

        if (prom_is_rex(magic))
                rex_clear_cache();

        /* Register the early console.  */
        register_prom_console();

        /* Were we compiled with the right CPU option? */
#if defined(CONFIG_CPU_R3000)
        if ((current_cpu_type() == CPU_R4000SC) ||
            (current_cpu_type() == CPU_R4400SC)) {
                static const char r4k_msg[] __initconst =
                        "Please recompile with \"CONFIG_CPU_R4X00 = y\".\n";
                printk(cpu_msg);
                printk(r4k_msg);
                dec_machine_halt();
        }
#endif

#if defined(CONFIG_CPU_R4X00)
        if ((current_cpu_type() == CPU_R3000) ||
            (current_cpu_type() == CPU_R3000A)) {
                static const char r3k_msg[] __initconst =
                        "Please recompile with \"CONFIG_CPU_R3000 = y\".\n";
                printk(cpu_msg);
                printk(r3k_msg);
                dec_machine_halt();
        }
#endif

        prom_meminit(magic);
        prom_identify_arch(magic);
        prom_init_cmdline(argc, argv, magic);
}