freebsd-skq/usr.sbin/acpi/acpidump/acpi_user.c

/*-
 * Copyright (c) 1999 Doug Rabson
 * Copyright (c) 2000 Mitsuru IWASAKI <iwasaki@FreeBSD.org>
 * All rights reserved.
 *
 * 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 AUTHOR 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 AUTHOR 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.
 *
 *	$FreeBSD$
 */

#include <sys/param.h>
#include <sys/mman.h>
#include <sys/queue.h>
#include <sys/stat.h>
#include <sys/sysctl.h>

#include <err.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "acpidump.h"

static char	machdep_acpi_root[] = "machdep.acpi_root";
static int      acpi_mem_fd = -1;

struct acpi_user_mapping {
	LIST_ENTRY(acpi_user_mapping) link;
	vm_offset_t     pa;
	caddr_t         va;
	size_t          size;
};

LIST_HEAD(acpi_user_mapping_list, acpi_user_mapping) maplist;

static void
acpi_user_init(void)
{

	if (acpi_mem_fd == -1) {
		acpi_mem_fd = open("/dev/mem", O_RDONLY);
		if (acpi_mem_fd == -1)
			err(1, "opening /dev/mem");
		LIST_INIT(&maplist);
	}
}

static struct acpi_user_mapping *
acpi_user_find_mapping(vm_offset_t pa, size_t size)
{
	struct	acpi_user_mapping *map;

	/* First search for an existing mapping */
	for (map = LIST_FIRST(&maplist); map; map = LIST_NEXT(map, link)) {
		if (map->pa <= pa && map->size >= pa + size - map->pa)
			return (map);
	}

	/* Then create a new one */
	size = round_page(pa + size) - trunc_page(pa);
	pa = trunc_page(pa);
	map = malloc(sizeof(struct acpi_user_mapping));
	if (!map)
		errx(1, "out of memory");
	map->pa = pa;
	map->va = mmap(0, size, PROT_READ, MAP_SHARED, acpi_mem_fd, pa);
	map->size = size;
	if ((intptr_t) map->va == -1)
		err(1, "can't map address");
	LIST_INSERT_HEAD(&maplist, map, link);

	return (map);
}

/*
 * Public interfaces
 */
struct ACPIrsdp *
acpi_find_rsd_ptr()
{
	struct ACPIrsdp rsdp;
	u_long		addr;
	size_t		len;

	acpi_user_init();

	/* Attempt to use sysctl to find RSD PTR record */
	len = sizeof(addr);
	if (sysctlbyname(machdep_acpi_root, &addr, &len, NULL, 0) == 0) {	
		pread(acpi_mem_fd, &rsdp, sizeof(rsdp), addr);
		if (memcmp(rsdp.signature, "RSD PTR ", 8) != 0)
			errx(1, "sysctl %s does not point to RSDP",
			     machdep_acpi_root);
		len = 20;			/* size of ACPI 1.0 table */
		if (acpi_checksum(&rsdp, len))
			warnx("RSDP has invalid checksum");
		if (rsdp.revision > 0)
			len = rsdp.length;
		return (acpi_map_physical(addr, len));
	}

#if !defined(__ia64__) && !defined(__amd64__)
	/* On ia32, scan physical memory for RSD PTR if above failed */
	for (addr = 0UL; addr < 1024UL * 1024UL; addr += 16UL) {
		pread(acpi_mem_fd, &rsdp, 8, addr);
		if (memcmp(rsdp.signature, "RSD PTR ", 8))
			continue;
		/* Read the entire table. */
		pread(acpi_mem_fd, &rsdp, sizeof(rsdp), addr);
		len = 20;			/* size of ACPI 1.0 table */
		if (acpi_checksum(&rsdp, len))
			continue;
		if (rsdp.revision > 0)
			len = rsdp.length;
		return (acpi_map_physical(addr, len));
	}
#endif

	return (0);
}

void *
acpi_map_physical(vm_offset_t pa, size_t size)
{
	struct	acpi_user_mapping *map;

	map = acpi_user_find_mapping(pa, size);
	return (map->va + (pa - map->pa));
}

struct ACPIsdt *
dsdt_load_file(char *infile)
{
	struct ACPIsdt	*sdt;
	uint8_t		*dp;
	struct stat	 sb;

	if ((acpi_mem_fd = open(infile, O_RDONLY)) == -1)
		errx(1, "opening %s", infile);

	LIST_INIT(&maplist);

	if (fstat(acpi_mem_fd, &sb) == -1)
		errx(1, "fstat %s", infile);

	dp = mmap(0, sb.st_size, PROT_READ, MAP_PRIVATE, acpi_mem_fd, 0);
	if (dp == NULL)
		errx(1, "mmap %s", infile);

	sdt = (struct ACPIsdt *)dp;
	if (strncmp(dp, "DSDT", 4) != 0 || acpi_checksum(sdt, sdt->len) != 0)
		return (NULL);

	return (sdt);
}