/*      $NetBSD: mmu.c,v 1.9 2014/03/26 15:55:44 christos Exp $ */

/*-
 * Copyright (c) 2003 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Paul Kranenburg.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/boot_flag.h>
#include <lib/libsa/stand.h>
#include <machine/promlib.h>
#include <machine/ctlreg.h>
#include <machine/pte.h>
#include <sparc/sparc/asm.h>
#include <sparc/stand/common/promdev.h>

static int sun4_mmu3l;  /* sun4 3-lvl MMU */
static int rcookie;     /* sun4 3-lvl MMU region resource */
static int scookie;     /* sun4/sun4c MMU segment resource */
static int obmem;       /* SRMMU on-board memory space */

static int pmap_map4(vaddr_t va, paddr_t pa, psize_t size);
static int pmap_extract4(vaddr_t va, paddr_t *ppa);
static int pmap_map_srmmu(vaddr_t va, paddr_t pa, psize_t size);
static int pmap_extract_srmmu(vaddr_t va, paddr_t *ppa);

int (*pmap_map)(vaddr_t va, paddr_t pa, psize_t size);
int (*pmap_extract)(vaddr_t va, paddr_t *ppa);

extern int boothowto;

int mmu_init(void)
{
        if (CPU_ISSUN4 || CPU_ISSUN4C) {
                pmap_map = pmap_map4;
                pmap_extract = pmap_extract4;
                if (CPU_ISSUN4) {
                        /* Find out if we're on a 3-lvl sun4 MMU. */
                        struct idprom *idp = prom_getidprom();
                        if (idp->idp_machtype == ID_SUN4_400)
                                sun4_mmu3l = 1;
                }
                /*
                 * XXX - we just guess which MMU cookies are free:
                 *       region 0 maps [0-16MB]
                 *       segment 0-16 map [0-4MB]
                 *       the PROM mappings use high-valued cookies.
                 */
                rcookie = 2;
                scookie = 17;
        } else if (CPU_ISSUN4M || CPU_ISSUN4D) {
                char buf[32];
                pmap_map = pmap_map_srmmu;
                pmap_extract = pmap_extract_srmmu;
                snprintf(buf, sizeof(buf), "obmem %lx L!", (u_long)&obmem);
                prom_interpret(buf);
        } else
                return (ENOTSUP);

        return (0);
}


/*
 * SUN4 & SUN4C VM routines.
 * Limited functionality wrt. MMU resource management.
 */
#define setregmap(va, smeg)     stha((va)+2, ASI_REGMAP, (smeg << 8))
#define setsegmap(va, pmeg)     (CPU_ISSUN4C \
                                        ? stba(va, ASI_SEGMAP, pmeg) \
                                        : stha(va, ASI_SEGMAP, pmeg))

int pmap_map4(vaddr_t va, paddr_t pa, psize_t size)
{
        u_int n = (size + NBPG - 1) >> PGSHIFT;
        u_int pte;

        if (sun4_mmu3l)
                setregmap((va & -NBPRG), rcookie++);

        if (boothowto & AB_VERBOSE)
                printf("Mapping %lx -> %lx (%d pages)\n", va, pa, n);
        setsegmap((va & -NBPSG), ++scookie);
        while (n--) {
                pte = PG_S | PG_V | PG_W | PG_NC | ((pa >> PGSHIFT) & PG_PFNUM);
                setpte4(va, pte);
                va += NBPG;
                pa += NBPG;
                if ((va & (NBPSG - 1)) == 0) {
                        if (boothowto & AB_VERBOSE)
                                printf("%d ", scookie);
                        setsegmap(va, ++scookie);
                }
        }
        if (boothowto & AB_VERBOSE)
                printf("\n");
        return (0);
}

int pmap_extract4(vaddr_t va, paddr_t *ppa)
{
        u_int pte;

        va &= -NBPG;
        pte = getpte4(va);
        if ((pte & PG_V) == 0)
                return (EFAULT);

        *ppa = (pte & PG_PFNUM) << PGSHIFT;
        return (0);
}


/*
 * SRMMU VM routines.
 * We use the PROM's Forth services to do all the hard work.
 */
int pmap_map_srmmu(vaddr_t va, paddr_t pa, psize_t size)
{
        char buf[64];

        snprintf(buf, sizeof(buf), "%lx %x %lx %lx map-pages",
            pa, obmem, va, size);

        if (boothowto & AB_VERBOSE)
                printf("Mapping kernel: %s\n", buf);

        prom_interpret(buf);
        return (0);
}

int pmap_extract_srmmu(vaddr_t va, paddr_t *ppa)
{
        char buf[32];
        u_int pte;

        va &= -NBPG;
        snprintf(buf, sizeof(buf), "%lx pgmap@ %lx L!", va, (u_long)&pte);
        prom_interpret(buf);
        if ((pte & SRMMU_TETYPE) != SRMMU_TEPTE)
                return (EFAULT);

        *ppa = (pte & SRMMU_PPNMASK) << SRMMU_PPNPASHIFT;
        return (0);
}