/*      $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);
}