src/soc/intel/apollolake/cpu.c

/*
 * This file is part of the coreboot project.
 *
 * Copyright (C) 2015-2016 Intel Corp.
 * (Written by Andrey Petrov <andrey.petrov@intel.com> for Intel Corp.)
 * (Written by Alexandru Gagniuc <alexandrux.gagniuc@intel.com> for Intel Corp.)
 *
 * 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.
 */

#include <console/console.h>
#include <cpu/cpu.h>
#include <cpu/x86/cache.h>
#include <cpu/x86/mp.h>
#include <cpu/x86/msr.h>
#include <cpu/x86/mtrr.h>
#include <device/device.h>
#include <device/pci.h>
#include <soc/cpu.h>
#include <soc/smm.h>

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

static struct cpu_device_id cpu_table[] = {
	{ X86_VENDOR_INTEL, CPUID_APOLLOLAKE_A0 },
	{ X86_VENDOR_INTEL, CPUID_APOLLOLAKE_B0 },
	{ 0, 0 },
};

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


/*
 * MP and SMM loading initialization.
 */
struct smm_relocation_attrs {
	uint32_t smbase;
	uint32_t smrr_base;
	uint32_t smrr_mask;
};

static struct smm_relocation_attrs relo_attrs;

static void read_cpu_topology(unsigned int *num_phys, unsigned int *num_virt)
{
	msr_t msr;
	msr = rdmsr(MSR_CORE_THREAD_COUNT);
	*num_virt = (msr.lo >> 0) & 0xffff;
	*num_phys = (msr.lo >> 16) & 0xffff;
}

/*
 * Do essential initialization tasks before APs can be fired up
 *
 * 1. Prevent race condition in MTRR solution. Enable MTRRs on the BSP. This
 * creates the MTRR solution that the APs will use. Otherwise APs will try to
 * apply the incomplete solution as the BSP is calculating it.
 */
static void pre_mp_init(void)
{
	x86_setup_mtrrs_with_detect();
	x86_mtrr_check();
}

/* Find CPU topology */
static int get_cpu_count(void)
{
	unsigned int num_virt_cores, num_phys_cores;

	read_cpu_topology(&num_phys_cores, &num_virt_cores);

	printk(BIOS_DEBUG, "Detected %u core, %u thread CPU.\n",
	       num_phys_cores, num_virt_cores);

	return num_virt_cores;
}

static void get_smm_info(uintptr_t *perm_smbase, size_t *perm_smsize,
				size_t *smm_save_state_size)
{
	void *smm_base;
	size_t smm_size;

	/* All range registers are aligned to 4KiB */
	const uint32_t rmask = ~((1 << 12) - 1);

	/* Initialize global tracking state. */
	smm_region(&smm_base, &smm_size);
	relo_attrs.smbase = (uint32_t)smm_base;
	relo_attrs.smrr_base = relo_attrs.smbase | MTRR_TYPE_WRBACK;
	relo_attrs.smrr_mask = ~(smm_size - 1) & rmask;
	relo_attrs.smrr_mask |= MTRR_PHYS_MASK_VALID;

	*perm_smbase = relo_attrs.smbase;
	*perm_smsize = smm_size - CONFIG_SMM_RESERVED_SIZE;
	*smm_save_state_size = sizeof(em64t100_smm_state_save_area_t);
}

static void relocation_handler(int cpu, uintptr_t curr_smbase,
				uintptr_t staggered_smbase)
{
	msr_t smrr;
	em64t100_smm_state_save_area_t *smm_state;
	/* Set up SMRR. */
	smrr.lo = relo_attrs.smrr_base;
	smrr.hi = 0;
	wrmsr(SMRR_PHYS_BASE, smrr);
	smrr.lo = relo_attrs.smrr_mask;
	smrr.hi = 0;
	wrmsr(SMRR_PHYS_MASK, smrr);
	smm_state = (void *)(SMM_EM64T100_SAVE_STATE_OFFSET + curr_smbase);
	smm_state->smbase = staggered_smbase;
}
/*
 * CPU initialization recipe
 *
 * Note that no microcode update is passed to the init function. CSE updates
 * the microcode on all cores before releasing them from reset. That means that
 * the BSP and all APs will come up with the same microcode revision.
 */
static const struct mp_ops mp_ops = {
	.pre_mp_init = pre_mp_init,
	.get_cpu_count = get_cpu_count,
	.get_smm_info = get_smm_info,
	.pre_mp_smm_init = southbridge_smm_clear_state,
	.relocation_handler = relocation_handler,
	.post_mp_init = southbridge_smm_enable_smi,
};

void apollolake_init_cpus(device_t dev)
{
	/* Clear for take-off */
	if (mp_init_with_smm(dev->link_list, &mp_ops) < 0)
		printk(BIOS_ERR, "MP initialization failure.\n");
}