/*	$OpenBSD: apmprobe.c,v 1.18 2014/07/08 13:31:30 deraadt Exp $	*/

/*
 * Copyright (c) 1997-2000 Michael Shalayeff
 * 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 ``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 HIS RELATIVES 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 MIND, 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.
 */
/*
 * APM derived from: apm_init.S, LP (Laptop Package)
 * wich contained this:
 * Copyright (C) 1994 by HOSOKAWA, Tatsumi <hosokawa@mt.cs.keio.ac.jp>
 *
 */
/*
 * If you want to know the specification of APM BIOS, see the following
 * documentations,
 *
 * [1] Intel Corporation and Microsoft Corporation, "Advanced Power
 *     Management, The Next Generation, Version 1.0", Feb.,1992.
 *
 * [2] Intel Corporation and Microsoft Corporation, "Advanced Power
 *     Management (APM) BIOS Interface Specification Revision 1.1",
 *     Sep.,1993, Intel Order Number: 241704-001, Microsoft Part
 *     Number: 781-110-X01
 *
 * or contact
 *
 * APM Support Desk (Intel Corporation, US)
 *   TEL: (800)628-8686
 *   FAX: (916)356-6100.
 */

#include <sys/param.h>
#include "libsa.h"
#include <stand/boot/bootarg.h>

#include <dev/isa/isareg.h>

#include <machine/apmvar.h>
#include <machine/biosvar.h>

#include "debug.h"

extern int debug;

static __inline u_int
apm_check(void)
{
	register u_int detail;
	register u_int8_t f;

	__asm volatile(DOINT(0x15) "\n\t"
	    "setc %b1\n\t"
	    "movzwl %%ax, %0\n\t"
	    "shll $16, %%ecx\n\t"
	    "orl %%ecx, %0"
	    : "=a" (detail), "=b" (f)
	    : "0" (APM_INSTCHECK), "1" (APM_DEV_APM_BIOS)
	    : "%ecx", "cc");

	if (f || BIOS_regs.biosr_bx != 0x504d /* "PM" */ ) {
#ifdef DEBUG
		if (debug)
			printf("apm_check: %x, %x, %x\n",
			    f, BIOS_regs.biosr_bx, detail);
#endif
		return 0;
	} else
		return detail;
}

static __inline int
apm_disconnect(void)
{
	register u_int16_t rv;

	__asm volatile(DOINT(0x15) "\n\t"
	    "setc %b0"
	    : "=a" (rv)
	    : "0" (APM_DISCONNECT), "b" (APM_DEV_APM_BIOS)
	    : "%ecx", "%edx", "cc");

	return ((rv & 0xff)? rv >> 8 : 0);
}

static __inline int
apm_connect(bios_apminfo_t *ai)
{
	register u_int16_t f;

	__asm volatile (DOINT(0x15) "\n\t"
	    "setc %b1\n\t"
	    "movb %%ah, %h1\n\t"
	    "movzwl %%ax, %%eax\n\tshll $4, %0\n\t"
	    "movzwl %%cx, %%ecx\n\tshll $4, %2\n\t"
	    "movzwl %%dx, %%edx\n\tshll $4, %3\n\t"
	    : "=a" (ai->apm_code32_base),
	      "=b" (f),
	      "=c" (ai->apm_code16_base),
	      "=d" (ai->apm_data_base)
	    : "0" (APM_PROT32_CONNECT), "1" (APM_DEV_APM_BIOS)
	    : "cc");

	if (f & 0xff)
		return (f >> 8);

	ai->apm_entry      = BIOS_regs.biosr_bx;
#if 0
	ai->apm_code_len   = BIOS_regs.biosr_si & 0xffff;
	ai->apm_code16_len = BIOS_regs.biosr_si & 0xffff;
	ai->apm_data_len   = BIOS_regs.biosr_di & 0xffff;
#else
	ai->apm_code_len   = 0xffff - (ai->apm_code32_base & 0xffff);
	ai->apm_code16_len = 0xffff - (ai->apm_code16_base & 0xffff);
	ai->apm_data_len   = 0xffff - (ai->apm_data_base & 0xffff);
#endif
	if (ai->apm_data_base < BOOTARG_OFF)
		ai->apm_data_len = PAGE_SIZE - (ai->apm_data_base & PAGE_MASK) - 1;

#ifdef DEBUG
	if (debug)
		printf("cs=%x:%x/%x:%x, ds=%x:%x\n",
		    ai->apm_code32_base, ai->apm_code_len,
		    ai->apm_code16_base, ai->apm_code16_len,
		    ai->apm_data_base,   ai->apm_data_len);
#endif
	/* inform apm bios about our driver version */
	__asm volatile (DOINT(0x15) "\n\t"
	    "setc %b1\n\t"
	    "movb %%ah, %h1"
	    : "=b" (f)
	    : "a" (APM_DRIVER_VERSION),
	      "0" (APM_DEV_APM_BIOS),
	      "c" (APM_VERSION)
	    : "cc");

	return 0;
}

static bios_apminfo_t ai;

void
apmprobe(void)
{
	if ((ai.apm_detail = apm_check())) {

		apm_disconnect();

		if (apm_connect(&ai) != 0) {
#ifdef DEBUG
			printf("\napm: connect error\n");
#endif
			return;
		}
#ifdef DEBUG
		if (debug)
			printf("apm[%x cs=%x[%x]/%x[%x] ds=%x[%x] @ %x]",
			    ai.apm_detail,
			    ai.apm_code32_base, ai.apm_code_len,
			    ai.apm_code16_base, ai.apm_code16_len,
			    ai.apm_data_base, ai.apm_data_len,
			    ai.apm_entry);
		else
			printf(" apm");
#else
		printf(" apm");
#endif
		addbootarg(BOOTARG_APMINFO, sizeof(ai), &ai);
	}
}

#define round_page(x)   (((x) + PAGE_MASK) & ~PAGE_MASK)
#define trunc_page(x)   ((x) & ~PAGE_MASK)

void
apmfixmem(void)
{
#ifdef DEBUG
	printf("apmremove (%d)", ai.apm_detail);
#endif
	if (ai.apm_detail)
		mem_delete(trunc_page(ai.apm_data_base),
		    round_page(ai.apm_data_base + ai.apm_data_len));
}
