/*
 *  boot.c - Architecture-Specific Low-Level ACPI Boot Support
 *
 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
 *  Copyright (C) 2001 Jun Nakajima <jun.nakajima@intel.com>
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */

#include <linux/init.h>
#include <linux/config.h>
#include <linux/acpi.h>
#include <asm/pgalloc.h>
#include <asm/apic.h>
#include <asm/io.h>
#include <asm/mpspec.h>

#if defined (CONFIG_X86_LOCAL_APIC)
#include <mach_apic.h>
#include <mach_mpparse.h>
#endif

#define PREFIX			"ACPI: "

extern int acpi_disabled;

/* --------------------------------------------------------------------------
                              Boot-time Configuration
   -------------------------------------------------------------------------- */

enum acpi_irq_model_id		acpi_irq_model;

/*
 * Temporarily use the virtual area starting from FIX_IO_APIC_BASE_END,
 * to map the target physical address. The problem is that set_fixmap()
 * provides a single page, and it is possible that the page is not
 * sufficient.
 * By using this area, we can map up to MAX_IO_APICS pages temporarily,
 * i.e. until the next __va_range() call.
 *
 * Important Safety Note:  The fixed I/O APIC page numbers are *subtracted*
 * from the fixed base.  That's why we start at FIX_IO_APIC_BASE_END and
 * count idx down while incrementing the phys address.
 */
char *__acpi_map_table(unsigned long phys, unsigned long size)
{
	unsigned long base, offset, mapped_size;
	int idx;

	if (phys + size < 8*1024*1024) 
		return __va(phys); 

	offset = phys & (PAGE_SIZE - 1);
	mapped_size = PAGE_SIZE - offset;
	set_fixmap(FIX_ACPI_END, phys);
	base = fix_to_virt(FIX_ACPI_END);

	/*
	 * Most cases can be covered by the below.
	 */
	idx = FIX_ACPI_END;
	while (mapped_size < size) {
		if (--idx < FIX_ACPI_BEGIN)
			return 0;	/* cannot handle this */
		phys += PAGE_SIZE;
		set_fixmap(idx, phys);
		mapped_size += PAGE_SIZE;
	}

	return ((unsigned char *) base + offset);
}


#ifdef CONFIG_X86_LOCAL_APIC

int acpi_lapic;

static u64 acpi_lapic_addr __initdata = APIC_DEFAULT_PHYS_BASE;


static int __init
acpi_parse_madt (
	unsigned long		phys_addr,
	unsigned long		size)
{
	struct acpi_table_madt	*madt = NULL;

	if (!phys_addr || !size)
		return -EINVAL;

	madt = (struct acpi_table_madt *) __acpi_map_table(phys_addr, size);
	if (!madt) {
		printk(KERN_WARNING PREFIX "Unable to map MADT\n");
		return -ENODEV;
	}

	if (madt->lapic_address)
		acpi_lapic_addr = (u64) madt->lapic_address;

	printk(KERN_INFO PREFIX "Local APIC address 0x%08x\n",
		madt->lapic_address);

	acpi_madt_oem_check(madt->header.oem_id, madt->header.oem_table_id);
	
	return 0;
}


static int __init
acpi_parse_lapic (
	acpi_table_entry_header *header)
{
	struct acpi_table_lapic	*processor = NULL;

	processor = (struct acpi_table_lapic*) header;
	if (!processor)
		return -EINVAL;

	acpi_table_print_madt_entry(header);

	mp_register_lapic (
		processor->id,					   /* APIC ID */
		processor->flags.enabled);			  /* Enabled? */

	return 0;
}


static int __init
acpi_parse_lapic_addr_ovr (
	acpi_table_entry_header *header)
{
	struct acpi_table_lapic_addr_ovr *lapic_addr_ovr = NULL;

	lapic_addr_ovr = (struct acpi_table_lapic_addr_ovr*) header;
	if (!lapic_addr_ovr)
		return -EINVAL;

	acpi_lapic_addr = lapic_addr_ovr->address;

	return 0;
}

#ifndef CONFIG_ACPI_HT_ONLY

static int __init
acpi_parse_lapic_nmi (
	acpi_table_entry_header *header)
{
	struct acpi_table_lapic_nmi *lapic_nmi = NULL;

	lapic_nmi = (struct acpi_table_lapic_nmi*) header;
	if (!lapic_nmi)
		return -EINVAL;

	acpi_table_print_madt_entry(header);

	if (lapic_nmi->lint != 1)
		printk(KERN_WARNING PREFIX "NMI not connected to LINT 1!\n");

	return 0;
}

#endif /*CONFIG_ACPI_HT_ONLY*/

#endif /*CONFIG_X86_LOCAL_APIC*/

#ifdef CONFIG_X86_IO_APIC

int acpi_ioapic;

#ifndef CONFIG_ACPI_HT_ONLY

static int __init
acpi_parse_ioapic (
	acpi_table_entry_header *header)
{
	struct acpi_table_ioapic *ioapic = NULL;

	ioapic = (struct acpi_table_ioapic*) header;
	if (!ioapic)
		return -EINVAL;
 
	acpi_table_print_madt_entry(header);

	mp_register_ioapic (
		ioapic->id,
		ioapic->address,
		ioapic->global_irq_base);
 
	return 0;
}


static int __init
acpi_parse_int_src_ovr (
	acpi_table_entry_header *header)
{
	struct acpi_table_int_src_ovr *intsrc = NULL;

	intsrc = (struct acpi_table_int_src_ovr*) header;
	if (!intsrc)
		return -EINVAL;

	acpi_table_print_madt_entry(header);

	mp_override_legacy_irq (
		intsrc->bus_irq,
		intsrc->flags.polarity,
		intsrc->flags.trigger,
		intsrc->global_irq);

	return 0;
}


static int __init
acpi_parse_nmi_src (
	acpi_table_entry_header *header)
{
	struct acpi_table_nmi_src *nmi_src = NULL;

	nmi_src = (struct acpi_table_nmi_src*) header;
	if (!nmi_src)
		return -EINVAL;

	acpi_table_print_madt_entry(header);

	/* TBD: Support nimsrc entries? */

	return 0;
}

#endif /*!CONFIG_ACPI_HT_ONLY*/ 
#endif /*CONFIG_X86_IO_APIC*/


static unsigned long __init
acpi_scan_rsdp (
	unsigned long		start,
	unsigned long		length)
{
	unsigned long		offset = 0;
	unsigned long		sig_len = sizeof("RSD PTR ") - 1;

	/*
	 * Scan all 16-byte boundaries of the physical memory region for the
	 * RSDP signature.
	 */
	for (offset = 0; offset < length; offset += 16) {
		if (strncmp((char *) (start + offset), "RSD PTR ", sig_len))
			continue;
		return (start + offset);
	}

	return 0;
}


unsigned long __init
acpi_find_rsdp (void)
{
	unsigned long		rsdp_phys = 0;

	/*
	 * Scan memory looking for the RSDP signature. First search EBDA (low
	 * memory) paragraphs and then search upper memory (E0000-FFFFF).
	 */
	rsdp_phys = acpi_scan_rsdp (0, 0x400);
	if (!rsdp_phys)
		rsdp_phys = acpi_scan_rsdp (0xE0000, 0xFFFFF);

	return rsdp_phys;
}


int __init
acpi_boot_init (void)
{
	int			result = 0;

	/*
	 * The default interrupt routing model is PIC (8259).  This gets
	 * overriden if IOAPICs are enumerated (below).
	 */
	acpi_irq_model = ACPI_IRQ_MODEL_PIC;

	/* 
	 * Initialize the ACPI boot-time table parser.
	 */
	result = acpi_table_init();
	if (result)
		return result;

	result = acpi_blacklisted();
	if (result) {
		acpi_disabled = 1;
		return result;
	}
	else
		printk(KERN_NOTICE PREFIX "BIOS passes blacklist\n");

#ifdef CONFIG_X86_LOCAL_APIC

	/* 
	 * MADT
	 * ----
	 * Parse the Multiple APIC Description Table (MADT), if exists.
	 * Note that this table provides platform SMP configuration 
	 * information -- the successor to MPS tables.
	 */

	result = acpi_table_parse(ACPI_APIC, acpi_parse_madt);
	if (!result) {
		printk(KERN_WARNING PREFIX "MADT not present\n");
		return 0;
	}
	else if (result < 0) {
		printk(KERN_ERR PREFIX "Error parsing MADT\n");
		return result;
	}
	else if (result > 1) 
		printk(KERN_WARNING PREFIX "Multiple MADT tables exist\n");

	/* 
	 * Local APIC
	 * ----------
	 * Note that the LAPIC address is obtained from the MADT (32-bit value)
	 * and (optionally) overriden by a LAPIC_ADDR_OVR entry (64-bit value).
	 */

	result = acpi_table_parse_madt(ACPI_MADT_LAPIC_ADDR_OVR, acpi_parse_lapic_addr_ovr);
	if (result < 0) {
		printk(KERN_ERR PREFIX "Error parsing LAPIC address override entry\n");
		return result;
	}

	mp_register_lapic_address(acpi_lapic_addr);

	result = acpi_table_parse_madt(ACPI_MADT_LAPIC, acpi_parse_lapic);
	if (!result) { 
		printk(KERN_ERR PREFIX "No LAPIC entries present\n");
		/* TBD: Cleanup to allow fallback to MPS */
		return -ENODEV;
	}
	else if (result < 0) {
		printk(KERN_ERR PREFIX "Error parsing LAPIC entry\n");
		/* TBD: Cleanup to allow fallback to MPS */
		return result;
	}

#ifndef CONFIG_ACPI_HT_ONLY
	result = acpi_table_parse_madt(ACPI_MADT_LAPIC_NMI, acpi_parse_lapic_nmi);
	if (result < 0) {
		printk(KERN_ERR PREFIX "Error parsing LAPIC NMI entry\n");
		/* TBD: Cleanup to allow fallback to MPS */
		return result;
	}
#endif /*!CONFIG_ACPI_HT_ONLY*/

	acpi_lapic = 1;

#endif /*CONFIG_X86_LOCAL_APIC*/

#ifdef CONFIG_X86_IO_APIC
#ifndef CONFIG_ACPI_HT_ONLY

	/* 
	 * I/O APIC 
	 * --------
	 */

	result = acpi_table_parse_madt(ACPI_MADT_IOAPIC, acpi_parse_ioapic);
	if (!result) { 
		printk(KERN_ERR PREFIX "No IOAPIC entries present\n");
		return -ENODEV;
	}
	else if (result < 0) {
		printk(KERN_ERR PREFIX "Error parsing IOAPIC entry\n");
		return result;
	}

	/* Build a default routing table for legacy (ISA) interrupts. */
	mp_config_acpi_legacy_irqs();

	result = acpi_table_parse_madt(ACPI_MADT_INT_SRC_OVR, acpi_parse_int_src_ovr);
	if (result < 0) {
		printk(KERN_ERR PREFIX "Error parsing interrupt source overrides entry\n");
		/* TBD: Cleanup to allow fallback to MPS */
		return result;
	}

	result = acpi_table_parse_madt(ACPI_MADT_NMI_SRC, acpi_parse_nmi_src);
	if (result < 0) {
		printk(KERN_ERR PREFIX "Error parsing NMI SRC entry\n");
		/* TBD: Cleanup to allow fallback to MPS */
		return result;
	}

	acpi_irq_model = ACPI_IRQ_MODEL_IOAPIC;

	acpi_ioapic = 1;

#endif /*!CONFIG_ACPI_HT_ONLY*/
#endif /*CONFIG_X86_IO_APIC*/

#ifdef CONFIG_X86_LOCAL_APIC
	if (acpi_lapic && acpi_ioapic) {
		smp_found_config = 1;
		clustered_apic_check();
	}
#endif

	return 0;
}
