/* $OpenBSD: prom.c,v 1.19 2025/06/29 15:55:21 miod Exp $ */
/* $NetBSD: prom.c,v 1.39 2000/03/06 21:36:05 thorpej Exp $ */

/* 
 * Copyright (c) 1992, 1994, 1995, 1996 Carnegie Mellon University
 * All Rights Reserved.
 * 
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 * 
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 * 
 * Carnegie Mellon requests users of this software to return to
 * 
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 * 
 * any improvements or extensions that they make and grant Carnegie Mellon
 * the rights to redistribute these changes.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <uvm/uvm_extern.h>
#include <sys/proc.h>
#include <sys/user.h>
#include <sys/mutex.h>

#include <machine/cpu.h>
#include <machine/rpb.h>
#define ENABLEPROM
#include <machine/prom.h>

#include <dev/cons.h>

/* XXX this is to fake out the console routines, while booting. */
struct consdev promcons = { NULL, NULL, promcngetc, promcnputc,
                            nullcnpollc, NULL, makedev(23,0), 1 };

struct rpb      *hwrpb;
int             alpha_console;

extern struct prom_vec prom_dispatch_v;

struct mutex prom_lock = MUTEX_INITIALIZER(IPL_HIGH);

void    prom_enter(void);
void    prom_leave(void);

void
init_prom_interface(struct rpb *rpb)
{
        struct crb *c;

        c = (struct crb *)((char *)rpb + rpb->rpb_crb_off);

        prom_dispatch_v.routine_arg = c->crb_v_dispatch;
        prom_dispatch_v.routine = c->crb_v_dispatch->entry_va;
}

void
init_bootstrap_console(void)
{
        char buf[4];

        init_prom_interface(hwrpb);

        prom_getenv(PROM_E_TTY_DEV, buf, 4);
        alpha_console = buf[0] - '0';

        /* XXX fake out the console routines, for now */
        cn_tab = &promcons;
}

void
prom_enter(void)
{
        mtx_enter(&prom_lock);
}

void
prom_leave(void)
{
        mtx_leave(&prom_lock);
}

/*
 * promcnputc:
 *
 * Remap char before passing off to prom.
 *
 * Prom only takes 32 bit addresses. Copy char somewhere prom can
 * find it. This routine will stop working after pmap_rid_of_console
 * is called in alpha_init. This is due to the hard coded address
 * of the console area.
 */
void
promcnputc(dev_t dev, int c)
{
        prom_return_t ret;
        unsigned char *to = (unsigned char *)0x20000000;

        prom_enter();   /* lock and map prom */
        *to = c;

        do {
                ret.bits = prom_putstr(alpha_console, to, 1);
        } while ((ret.u.retval & 1) == 0);

        prom_leave();           /* unmap prom and unlock */
}

/*
 * promcngetc:
 *
 * Wait for the prom to get a real char and pass it back.
 */
int
promcngetc(dev_t dev)
{
        prom_return_t ret;

        for (;;) {
                prom_enter();
                ret.bits = prom_getc(alpha_console);
                prom_leave();
                if (ret.u.status == 0 || ret.u.status == 1)
                        return (ret.u.retval);
        }
}

int
prom_getenv(int id, char *buf, int len)
{
        unsigned char *to = (unsigned char *)0x20000000;
        prom_return_t ret;

        prom_enter();
        ret.bits = prom_getenv_disp(id, to, len);
        bcopy(to, buf, len);
        prom_leave();

        if (ret.u.status & 0x4)
                ret.u.retval = 0;
        buf[ret.u.retval] = '\0';

        return (ret.bits);
}

void
prom_halt(int halt)
{
        struct pcs *p;

        /*
         * Turn off interrupts, for sanity.
         */
        (void) splhigh();

        /*
         * Set "boot request" part of the CPU state depending on what
         * we want to happen when we halt.
         */
        p = LOCATE_PCS(hwrpb, hwrpb->rpb_primary_cpu_id);
        p->pcs_flags &= ~(PCS_RC | PCS_HALT_REQ);
        if (halt)
                p->pcs_flags |= PCS_HALT_STAY_HALTED;
        else
                p->pcs_flags |= PCS_HALT_WARM_BOOT;

        /*
         * Halt the machine.
         */
        alpha_pal_halt();
}

u_int64_t
hwrpb_checksum(void)
{
        u_int64_t *p, sum;
        int i;

        for (i = 0, p = (u_int64_t *)hwrpb, sum = 0;
            i < (offsetof(struct rpb, rpb_checksum) / sizeof (u_int64_t));
            i++, p++)
                sum += *p;

        return (sum);
}

void
hwrpb_primary_init(void)
{
        struct pcs *p;

        p = LOCATE_PCS(hwrpb, hwrpb->rpb_primary_cpu_id);

        /* Initialize the primary's HWPCB and the Virtual Page Table Base. */
        bcopy(&proc0.p_addr->u_pcb.pcb_hw, p->pcs_hwpcb,
            sizeof proc0.p_addr->u_pcb.pcb_hw);
        hwrpb->rpb_vptb = VPTBASE;

        hwrpb->rpb_checksum = hwrpb_checksum();
}

void
hwrpb_restart_setup(void)
{
        struct pcs *p;

        /* Clear bootstrap-in-progress flag since we're done bootstrapping */
        p = LOCATE_PCS(hwrpb, hwrpb->rpb_primary_cpu_id);
        p->pcs_flags &= ~PCS_BIP;

        /* when 'c'ontinuing from console halt, do a dump */
        hwrpb->rpb_rest_term = (u_int64_t)&XentRestart;
        hwrpb->rpb_rest_term_val = 0x1;

        hwrpb->rpb_checksum = hwrpb_checksum();

        p->pcs_flags |= (PCS_RC | PCS_CV);
}

u_int64_t
console_restart(struct trapframe *framep)
{
        struct pcs *p;

        /* Clear restart-capable flag, since we can no longer restart. */
        p = LOCATE_PCS(hwrpb, hwrpb->rpb_primary_cpu_id);
        p->pcs_flags &= ~PCS_RC;

        /* Fill in the missing frame slots */

        framep->tf_regs[FRAME_PS] = p->pcs_halt_ps;
        framep->tf_regs[FRAME_PC] = p->pcs_halt_pc;
        framep->tf_regs[FRAME_T11] = p->pcs_halt_r25;
        framep->tf_regs[FRAME_RA] = p->pcs_halt_r26;
        framep->tf_regs[FRAME_T12] = p->pcs_halt_r27;

        panic("user requested console halt");

        return (1);
}