/*
 * This file is part of the coreboot project.
 *
 * Copyright (C) 2007-2009 coresystems GmbH
 * Copyright (C) 2011 The ChromiumOS Authors.  All rights reserved.
 *
 * 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; version 2 of
 * the License.
 *
 * 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., 51 Franklin St, Fifth Floor, Boston,
 * MA 02110-1301 USA
 */

#include <console/console.h>
#include <device/device.h>
#include <string.h>
#include <arch/acpi.h>
#include <cpu/cpu.h>
#include <cpu/x86/mtrr.h>
#include <cpu/x86/msr.h>
#include <cpu/x86/lapic.h>
#include <cpu/intel/microcode.h>
#include <cpu/intel/speedstep.h>
#include <cpu/intel/turbo.h>
#include <cpu/x86/cache.h>
#include <cpu/x86/name.h>
#include <pc80/mc146818rtc.h>
#include "model_2065x.h"
#include "chip.h"

/*
 * List of supported C-states in this processor
 *
 * Latencies are typical worst-case package exit time in uS
 * taken from the SandyBridge BIOS specification.
 */
static acpi_cstate_t cstate_map[] = {
	{	/* 0: C0 */
	},{	/* 1: C1 */
		.latency = 1,
		.power = 1000,
		.resource = {
			.addrl = 0x00,	/* MWAIT State 0 */
			.space_id = ACPI_ADDRESS_SPACE_FIXED,
			.bit_width = ACPI_FFIXEDHW_VENDOR_INTEL,
			.bit_offset = ACPI_FFIXEDHW_CLASS_MWAIT,
			.resv = ACPI_FFIXEDHW_FLAG_HW_COORD,
		}
	},
	{	/* 2: C1E */
		.latency = 1,
		.power = 1000,
		.resource = {
			.addrl = 0x01,	/* MWAIT State 0 Sub-state 1 */
			.space_id = ACPI_ADDRESS_SPACE_FIXED,
			.bit_width = ACPI_FFIXEDHW_VENDOR_INTEL,
			.bit_offset = ACPI_FFIXEDHW_CLASS_MWAIT,
			.resv = ACPI_FFIXEDHW_FLAG_HW_COORD,
		}
	},
	{	/* 3: C3 */
		.latency = 63,
		.power = 500,
		.resource = {
			.addrl = 0x10,	/* MWAIT State 1 */
			.space_id = ACPI_ADDRESS_SPACE_FIXED,
			.bit_width = ACPI_FFIXEDHW_VENDOR_INTEL,
			.bit_offset = ACPI_FFIXEDHW_CLASS_MWAIT,
			.resv = ACPI_FFIXEDHW_FLAG_HW_COORD,
		}
	},
	{	/* 4: C6 */
		.latency = 87,
		.power = 350,
		.resource = {
			.addrl = 0x20,	/* MWAIT State 2 */
			.space_id = ACPI_ADDRESS_SPACE_FIXED,
			.bit_width = ACPI_FFIXEDHW_VENDOR_INTEL,
			.bit_offset = ACPI_FFIXEDHW_CLASS_MWAIT,
			.resv = ACPI_FFIXEDHW_FLAG_HW_COORD,
		}
	},
	{	/* 5: C7 */
		.latency = 90,
		.power = 200,
		.resource = {
			.addrl = 0x30,	/* MWAIT State 3 */
			.space_id = ACPI_ADDRESS_SPACE_FIXED,
			.bit_width = ACPI_FFIXEDHW_VENDOR_INTEL,
			.bit_offset = ACPI_FFIXEDHW_CLASS_MWAIT,
			.resv = ACPI_FFIXEDHW_FLAG_HW_COORD,
		}
	},
	{	/* 6: C7S */
		.latency = 90,
		.power = 200,
		.resource = {
			.addrl = 0x31,	/* MWAIT State 3 Sub-state 1 */
			.space_id = ACPI_ADDRESS_SPACE_FIXED,
			.bit_width = ACPI_FFIXEDHW_VENDOR_INTEL,
			.bit_offset = ACPI_FFIXEDHW_CLASS_MWAIT,
			.resv = ACPI_FFIXEDHW_FLAG_HW_COORD,
		}
	},
	{ 0 }
};

static void enable_vmx(void)
{
	struct cpuid_result regs;
	msr_t msr;
	int enable = CONFIG_ENABLE_VMX;

	regs = cpuid(1);
	/* Check that the VMX is supported before reading or writing the MSR. */
	if (!((regs.ecx & CPUID_VMX) || (regs.ecx & CPUID_SMX)))
		return;

	msr = rdmsr(IA32_FEATURE_CONTROL);

	if (msr.lo & (1 << 0)) {
		printk(BIOS_ERR, "VMX is locked, so %s will do nothing\n", __func__);
		/* VMX locked. If we set it again we get an illegal
		 * instruction
		 */
		return;
	}

	/* The IA32_FEATURE_CONTROL MSR may initialize with random values.
	 * It must be cleared regardless of VMX config setting.
	 */
	msr.hi = msr.lo = 0;

	printk(BIOS_DEBUG, "%s VMX\n", enable ? "Enabling" : "Disabling");

	/* Even though the Intel manual says you must set the lock bit in addition
	 * to the VMX bit in order for VMX to work, it is incorrect.  Thus we leave
	 * it unlocked for the OS to manage things itself.  This is good for a few
	 * reasons:
	 * - No need to reflash the bios just to toggle the lock bit.
	 * - The VMX bits really really should match each other across cores, so
	 *   hard locking it on one while another has the opposite setting can
	 *   easily lead to crashes as code using VMX migrates between them.
	 * - Vendors that want to "upsell" from a bios that disables+locks to
	 *   one that doesn't is sleazy.
	 * By leaving this to the OS (e.g. Linux), people can do exactly what they
	 * want on the fly, and do it correctly (e.g. across multiple cores).
	 */
	if (enable) {
		msr.lo |= (1 << 2);
		if (regs.ecx & CPUID_SMX)
			msr.lo |= (1 << 1);
	}

	wrmsr(IA32_FEATURE_CONTROL, msr);
}


int cpu_config_tdp_levels(void)
{
	msr_t platform_info;

	/* Minimum CPU revision */
	if (cpuid_eax(1) < IVB_CONFIG_TDP_MIN_CPUID)
		return 0;

	/* Bits 34:33 indicate how many levels supported */
	platform_info = rdmsr(MSR_PLATFORM_INFO);
	return (platform_info.hi >> 1) & 3;
}


static void configure_thermal_target(void)
{
	struct cpu_intel_model_2065x_config *conf;
	struct device *lapic;
	msr_t msr;

	/* Find pointer to CPU configuration */
	lapic = dev_find_lapic(SPEEDSTEP_APIC_MAGIC);
	if (!lapic || !lapic->chip_info)
		return;
	conf = lapic->chip_info;

	/* Set TCC activation offset if supported */
	msr = rdmsr(MSR_PLATFORM_INFO);
	if ((msr.lo & (1 << 30)) && conf->tcc_offset) {
		msr = rdmsr(MSR_TEMPERATURE_TARGET);
		msr.lo &= ~(0xf << 24); /* Bits 27:24 */
		msr.lo |= (conf->tcc_offset & 0xf) << 24;
		wrmsr(MSR_TEMPERATURE_TARGET, msr);
	}
}

static void configure_misc(void)
{
	msr_t msr;

	msr = rdmsr(IA32_MISC_ENABLE);
	msr.lo |= (1 << 0);	  /* Fast String enable */
	msr.lo |= (1 << 3); 	  /* TM1/TM2/EMTTM enable */
	msr.lo |= (1 << 16);	  /* Enhanced SpeedStep Enable */
	wrmsr(IA32_MISC_ENABLE, msr);

	/* Disable Thermal interrupts */
	msr.lo = 0;
	msr.hi = 0;
	wrmsr(IA32_THERM_INTERRUPT, msr);

#ifdef DISABLED
	/* Enable package critical interrupt only */
	msr.lo = 1 << 4;
	msr.hi = 0;
	wrmsr(IA32_PACKAGE_THERM_INTERRUPT, msr);
#endif
}

static void enable_lapic_tpr(void)
{
	msr_t msr;

	msr = rdmsr(MSR_PIC_MSG_CONTROL);
	msr.lo &= ~(1 << 10);	/* Enable APIC TPR updates */
	wrmsr(MSR_PIC_MSG_CONTROL, msr);
}


static void set_max_ratio(void)
{
	msr_t msr, perf_ctl;

	perf_ctl.hi = 0;

	/* Check for configurable TDP option */
	if (cpu_config_tdp_levels()) {
		/* Set to nominal TDP ratio */
		msr = rdmsr(MSR_CONFIG_TDP_NOMINAL);
		perf_ctl.lo = (msr.lo & 0xff) << 8;
	} else {
		/* Platform Info bits 15:8 give max ratio */
		msr = rdmsr(MSR_PLATFORM_INFO);
		perf_ctl.lo = msr.lo & 0xff00;
	}
	wrmsr(IA32_PERF_CTL, perf_ctl);

	printk(BIOS_DEBUG, "model_x06ax: frequency set to %d\n",
	       ((perf_ctl.lo >> 8) & 0xff) * NEHALEM_BCLK);
}

static void set_energy_perf_bias(u8 policy)
{
#ifdef DISABLED
	msr_t msr;

	/* Energy Policy is bits 3:0 */
	msr = rdmsr(IA32_ENERGY_PERFORMANCE_BIAS);
	msr.lo &= ~0xf;
	msr.lo |= policy & 0xf;
	wrmsr(IA32_ENERGY_PERFORMANCE_BIAS, msr);

	printk(BIOS_DEBUG, "model_x06ax: energy policy set to %u\n",
	       policy);
#endif
}

static void configure_mca(void)
{
	msr_t msr;
	int i;

	msr.lo = msr.hi = 0;
	/* This should only be done on a cold boot */
	for (i = 0; i < 7; i++)
		wrmsr(IA32_MC0_STATUS + (i * 4), msr);
}

/*
 * Initialize any extra cores/threads in this package.
 */
static void intel_cores_init(struct device *cpu)
{
	struct cpuid_result result;
	unsigned threads_per_package, threads_per_core, i;

	/* Logical processors (threads) per core */
	result = cpuid_ext(0xb, 0);
	threads_per_core = result.ebx & 0xffff;

	/* Logical processors (threads) per package */
	result = cpuid_ext(0xb, 1);
	threads_per_package = result.ebx & 0xffff;

	/* Only initialize extra cores from BSP */
	if (cpu->path.apic.apic_id)
		return;

	printk(BIOS_DEBUG, "CPU: %u has %u cores, %u threads per core\n",
	       cpu->path.apic.apic_id, threads_per_package/threads_per_core,
	       threads_per_core);

	for (i = 1; i < threads_per_package; ++i) {
		struct device_path cpu_path;
		struct device *new;

		/* Build the cpu device path */
		cpu_path.type = DEVICE_PATH_APIC;
		cpu_path.apic.apic_id =
		  cpu->path.apic.apic_id + (i % threads_per_core)
			+ ((i / threads_per_core) << 2);

		/* Allocate the new cpu device structure */
		new = alloc_dev(cpu->bus, &cpu_path);
		if (!new)
			continue;

		printk(BIOS_DEBUG, "CPU: %u has core %u\n",
		       cpu->path.apic.apic_id,
		       new->path.apic.apic_id);

#if CONFIG_SMP && CONFIG_MAX_CPUS > 1
		/* Start the new cpu */
		if (!start_cpu(new)) {
			/* Record the error in cpu? */
			printk(BIOS_ERR, "CPU %u would not start!\n",
			       new->path.apic.apic_id);
		}
#endif
	}
}

static void model_2065x_init(struct device *cpu)
{
	char processor_name[49];
	struct cpuid_result cpuid_regs;

	/* Turn on caching if we haven't already */
	x86_enable_cache();

	intel_update_microcode_from_cbfs();

	/* Clear out pending MCEs */
	configure_mca();

	/* Print processor name */
	fill_processor_name(processor_name);
	printk(BIOS_INFO, "CPU: %s.\n", processor_name);
	printk(BIOS_INFO, "CPU:lapic=%ld, boot_cpu=%d\n", lapicid (), boot_cpu ());

	/* Setup MTRRs based on physical address size */
	cpuid_regs = cpuid(0x80000008);
	x86_setup_fixed_mtrrs();
	x86_setup_var_mtrrs(cpuid_regs.eax & 0xff, 2);
	x86_mtrr_check();

	/* Setup Page Attribute Tables (PAT) */
	// TODO set up PAT

	/* Enable the local cpu apics */
	enable_lapic_tpr();
	setup_lapic();

	/* Enable virtualization if enabled in CMOS */
	enable_vmx();

	/* Configure Enhanced SpeedStep and Thermal Sensors */
	configure_misc();

	/* Thermal throttle activation offset */
	configure_thermal_target();

	/* Set energy policy */
	set_energy_perf_bias(ENERGY_POLICY_NORMAL);

	/* Set Max Ratio */
	set_max_ratio();

	/* Enable Turbo */
	enable_turbo();

	/* Start up extra cores */
	intel_cores_init(cpu);
}

static struct device_operations cpu_dev_ops = {
	.init     = model_2065x_init,
};

static struct cpu_device_id cpu_table[] = {
	{ X86_VENDOR_INTEL, 0x20652 }, /* Intel Nehalem */
	{ X86_VENDOR_INTEL, 0x20655 }, /* Intel Nehalem */
	{ 0, 0 },
};

static const struct cpu_driver driver __cpu_driver = {
	.ops      = &cpu_dev_ops,
	.id_table = cpu_table,
	.cstates  = cstate_map,
};