prom.c

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/* Prom access routines for the sun3x */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/tty.h>
#include <linux/console.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/string.h>

#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/bootinfo.h>
#include <asm/setup.h>
#include <asm/traps.h>
#include <asm/sun3xprom.h>
#include <asm/idprom.h>
#include <asm/segment.h>
#include <asm/sun3ints.h>
#include <asm/openprom.h>
#include <asm/machines.h>

void (*sun3x_putchar)(int);
int (*sun3x_getchar)(void);
int (*sun3x_mayget)(void);
int (*sun3x_mayput)(int);
void (*sun3x_prom_reboot)(void);
e_vector sun3x_prom_abort;
struct linux_romvec *romvec;

/* prom vector table */
e_vector *sun3x_prom_vbr;

/* Handle returning to the prom */
void sun3x_halt(void)
{
    unsigned long flags;

    /* Disable interrupts while we mess with things */
    local_irq_save(flags);

    /* Restore prom vbr */
    asm volatile ("movec %0,%%vbr" : : "r" ((void*)sun3x_prom_vbr));

    /* Restore prom NMI clock */
//  sun3x_disable_intreg(5);
    sun3_enable_irq(7);

    /* Let 'er rip */
    asm volatile ("trap #14");

    /* Restore everything */
    sun3_disable_irq(7);
    sun3_enable_irq(5);

    asm volatile ("movec %0,%%vbr" : : "r" ((void*)vectors));
    local_irq_restore(flags);
}

void sun3x_reboot(void)
{
    /* This never returns, don't bother saving things */
    local_irq_disable();

    /* Restore prom vbr */
    asm volatile ("movec %0,%%vbr" : : "r" ((void*)sun3x_prom_vbr));

    /* Restore prom NMI clock */
    sun3_disable_irq(5);
    sun3_enable_irq(7);

    /* Let 'er rip */
    (*romvec->pv_reboot)("vmlinux");
}

static void sun3x_prom_write(struct console *co, const char *s,
                             unsigned int count)
{
    while (count--) {
        if (*s == '\n')
            sun3x_putchar('\r');
        sun3x_putchar(*s++);
    }
}

/* debug console - write-only */

static struct console sun3x_debug = {
    .name   = "debug",
    .write  = sun3x_prom_write,
    .flags  = CON_PRINTBUFFER,
    .index  = -1,
};

void __init sun3x_prom_init(void)
{
    /* Read the vector table */

    sun3x_putchar = *(void (**)(int)) (SUN3X_P_PUTCHAR);
    sun3x_getchar = *(int (**)(void)) (SUN3X_P_GETCHAR);
    sun3x_mayget = *(int (**)(void))  (SUN3X_P_MAYGET);
    sun3x_mayput = *(int (**)(int))   (SUN3X_P_MAYPUT);
    sun3x_prom_reboot = *(void (**)(void)) (SUN3X_P_REBOOT);
    sun3x_prom_abort = *(e_vector *)  (SUN3X_P_ABORT);
    romvec = (struct linux_romvec *)SUN3X_PROM_BASE;

    idprom_init();

    if (!((idprom->id_machtype & SM_ARCH_MASK) == SM_SUN3X)) {
        printk("Warning: machine reports strange type %02x\n",
            idprom->id_machtype);
        printk("Pretending it's a 3/80, but very afraid...\n");
        idprom->id_machtype = SM_SUN3X | SM_3_80;
    }

    /* point trap #14 at abort.
     * XXX this is futile since we restore the vbr first - oops
     */
    vectors[VEC_TRAP14] = sun3x_prom_abort;
}

static int __init sun3x_debug_setup(char *arg)
{
    /* If debug=prom was specified, start the debug console */
    if (MACH_IS_SUN3X && !strcmp(arg, "prom"))
        register_console(&sun3x_debug);
    return 0;
}

early_param("debug", sun3x_debug_setup);

/* some prom functions to export */
int prom_getintdefault(int node, char *property, int deflt)
{
    return deflt;
}

int prom_getbool (int node, char *prop)
{
    return 1;
}

void prom_printf(char *fmt, ...)
{
}

void prom_halt (void)
{
    sun3x_halt();
}

/* Get the idprom and stuff it into buffer 'idbuf'.  Returns the
 * format type.  'num_bytes' is the number of bytes that your idbuf
 * has space for.  Returns 0xff on error.
 */
unsigned char
prom_get_idprom(char *idbuf, int num_bytes)
{
        int i;

    /* make a copy of the idprom structure */
    for (i = 0; i < num_bytes; i++)
        idbuf[i] = ((char *)SUN3X_IDPROM)[i];

        return idbuf[0];
}