/*
 * Copyright (c) 2016 Google, Inc
 *
 * SPDX-License-Identifier:     GPL-2.0
 *
 * Based on code from coreboot src/soc/intel/broadwell/cpu.c
 */

#include <common.h>
#include <dm.h>
#include <cpu.h>
#include <asm/cpu.h>
#include <asm/cpu_x86.h>
#include <asm/cpu_common.h>
#include <asm/intel_regs.h>
#include <asm/msr.h>
#include <asm/post.h>
#include <asm/turbo.h>
#include <asm/arch/cpu.h>
#include <asm/arch/pch.h>
#include <asm/arch/rcb.h>

struct cpu_broadwell_priv {
        bool ht_disabled;
};

/* Convert time in seconds to POWER_LIMIT_1_TIME MSR value */
static const u8 power_limit_time_sec_to_msr[] = {
        [0]   = 0x00,
        [1]   = 0x0a,
        [2]   = 0x0b,
        [3]   = 0x4b,
        [4]   = 0x0c,
        [5]   = 0x2c,
        [6]   = 0x4c,
        [7]   = 0x6c,
        [8]   = 0x0d,
        [10]  = 0x2d,
        [12]  = 0x4d,
        [14]  = 0x6d,
        [16]  = 0x0e,
        [20]  = 0x2e,
        [24]  = 0x4e,
        [28]  = 0x6e,
        [32]  = 0x0f,
        [40]  = 0x2f,
        [48]  = 0x4f,
        [56]  = 0x6f,
        [64]  = 0x10,
        [80]  = 0x30,
        [96]  = 0x50,
        [112] = 0x70,
        [128] = 0x11,
};

/* Convert POWER_LIMIT_1_TIME MSR value to seconds */
static const u8 power_limit_time_msr_to_sec[] = {
        [0x00] = 0,
        [0x0a] = 1,
        [0x0b] = 2,
        [0x4b] = 3,
        [0x0c] = 4,
        [0x2c] = 5,
        [0x4c] = 6,
        [0x6c] = 7,
        [0x0d] = 8,
        [0x2d] = 10,
        [0x4d] = 12,
        [0x6d] = 14,
        [0x0e] = 16,
        [0x2e] = 20,
        [0x4e] = 24,
        [0x6e] = 28,
        [0x0f] = 32,
        [0x2f] = 40,
        [0x4f] = 48,
        [0x6f] = 56,
        [0x10] = 64,
        [0x30] = 80,
        [0x50] = 96,
        [0x70] = 112,
        [0x11] = 128,
};

int arch_cpu_init_dm(void)
{
        struct udevice *dev;
        int ret;

        /* Start up the LPC so we have serial */
        ret = uclass_first_device(UCLASS_LPC, &dev);
        if (ret)
                return ret;
        if (!dev)
                return -ENODEV;
        ret = cpu_set_flex_ratio_to_tdp_nominal();
        if (ret)
                return ret;

        return 0;
}

void set_max_freq(void)
{
        msr_t msr, perf_ctl, platform_info;

        /* Check for configurable TDP option */
        platform_info = msr_read(MSR_PLATFORM_INFO);

        if ((platform_info.hi >> 1) & 3) {
                /* Set to nominal TDP ratio */
                msr = msr_read(MSR_CONFIG_TDP_NOMINAL);
                perf_ctl.lo = (msr.lo & 0xff) << 8;
        } else {
                /* Platform Info bits 15:8 give max ratio */
                msr = msr_read(MSR_PLATFORM_INFO);
                perf_ctl.lo = msr.lo & 0xff00;
        }

        perf_ctl.hi = 0;
        msr_write(IA32_PERF_CTL, perf_ctl);

        debug("CPU: frequency set to %d MHz\n",
              ((perf_ctl.lo >> 8) & 0xff) * CPU_BCLK);
}

int arch_cpu_init(void)
{
        post_code(POST_CPU_INIT);

        return x86_cpu_init_f();
}

int print_cpuinfo(void)
{
        char processor_name[CPU_MAX_NAME_LEN];
        const char *name;
        int ret;

        set_max_freq();

        ret = cpu_common_init();
        if (ret)
                return ret;
        gd->arch.pei_boot_mode = PEI_BOOT_NONE;

        /* Print processor name */
        name = cpu_get_name(processor_name);
        printf("CPU:   %s\n", name);

        return 0;
}

/*
 * The core 100MHz BLCK is disabled in deeper c-states. One needs to calibrate
 * the 100MHz BCLCK against the 24MHz BLCK to restore the clocks properly
 * when a core is woken up
 */
static int pcode_ready(void)
{
        int wait_count;
        const int delay_step = 10;

        wait_count = 0;
        do {
                if (!(readl(MCHBAR_REG(BIOS_MAILBOX_INTERFACE)) &
                                MAILBOX_RUN_BUSY))
                        return 0;
                wait_count += delay_step;
                udelay(delay_step);
        } while (wait_count < 1000);

        return -ETIMEDOUT;
}

static u32 pcode_mailbox_read(u32 command)
{
        int ret;

        ret = pcode_ready();
        if (ret) {
                debug("PCODE: mailbox timeout on wait ready\n");
                return ret;
        }

        /* Send command and start transaction */
        writel(command | MAILBOX_RUN_BUSY, MCHBAR_REG(BIOS_MAILBOX_INTERFACE));

        ret = pcode_ready();
        if (ret) {
                debug("PCODE: mailbox timeout on completion\n");
                return ret;
        }

        /* Read mailbox */
        return readl(MCHBAR_REG(BIOS_MAILBOX_DATA));
}

static int pcode_mailbox_write(u32 command, u32 data)
{
        int ret;

        ret = pcode_ready();
        if (ret) {
                debug("PCODE: mailbox timeout on wait ready\n");
                return ret;
        }

        writel(data, MCHBAR_REG(BIOS_MAILBOX_DATA));

        /* Send command and start transaction */
        writel(command | MAILBOX_RUN_BUSY, MCHBAR_REG(BIOS_MAILBOX_INTERFACE));

        ret = pcode_ready();
        if (ret) {
                debug("PCODE: mailbox timeout on completion\n");
                return ret;
        }

        return 0;
}

/* @dev is the CPU device */
static void initialize_vr_config(struct udevice *dev)
{
        int ramp, min_vid;
        msr_t msr;

        debug("Initializing VR config\n");

        /* Configure VR_CURRENT_CONFIG */
        msr = msr_read(MSR_VR_CURRENT_CONFIG);
        /*
         * Preserve bits 63 and 62. Bit 62 is PSI4 enable, but it is only valid
         * on ULT systems
         */
        msr.hi &= 0xc0000000;
        msr.hi |= (0x01 << (52 - 32)); /* PSI3 threshold -  1A */
        msr.hi |= (0x05 << (42 - 32)); /* PSI2 threshold -  5A */
        msr.hi |= (0x14 << (32 - 32)); /* PSI1 threshold - 20A */
        msr.hi |= (1 <<  (62 - 32)); /* Enable PSI4 */
        /* Leave the max instantaneous current limit (12:0) to default */
        msr_write(MSR_VR_CURRENT_CONFIG, msr);

        /* Configure VR_MISC_CONFIG MSR */
        msr = msr_read(MSR_VR_MISC_CONFIG);
        /* Set the IOUT_SLOPE scalar applied to dIout in U10.1.9 format */
        msr.hi &= ~(0x3ff << (40 - 32));
        msr.hi |= (0x200 << (40 - 32)); /* 1.0 */
        /* Set IOUT_OFFSET to 0 */
        msr.hi &= ~0xff;
        /* Set entry ramp rate to slow */
        msr.hi &= ~(1 << (51 - 32));
        /* Enable decay mode on C-state entry */
        msr.hi |= (1 << (52 - 32));
        /* Set the slow ramp rate */
        msr.hi &= ~(0x3 << (53 - 32));
        /* Configure the C-state exit ramp rate */
        ramp = fdtdec_get_int(gd->fdt_blob, dev->of_offset, "intel,slow-ramp",
                              -1);
        if (ramp != -1) {
                /* Configured slow ramp rate */
                msr.hi |= ((ramp & 0x3) << (53 - 32));
                /* Set exit ramp rate to slow */
                msr.hi &= ~(1 << (50 - 32));
        } else {
                /* Fast ramp rate / 4 */
                msr.hi |= (0x01 << (53 - 32));
                /* Set exit ramp rate to fast */
                msr.hi |= (1 << (50 - 32));
        }
        /* Set MIN_VID (31:24) to allow CPU to have full control */
        msr.lo &= ~0xff000000;
        min_vid = fdtdec_get_int(gd->fdt_blob, dev->of_offset, "intel,min-vid",
                                 0);
        msr.lo |= (min_vid & 0xff) << 24;
        msr_write(MSR_VR_MISC_CONFIG, msr);

        /*  Configure VR_MISC_CONFIG2 MSR */
        msr = msr_read(MSR_VR_MISC_CONFIG2);
        msr.lo &= ~0xffff;
        /*
         * Allow CPU to control minimum voltage completely (15:8) and
         * set the fast ramp voltage in 10mV steps
         */
        if (cpu_get_family_model() == BROADWELL_FAMILY_ULT)
                msr.lo |= 0x006a; /* 1.56V */
        else
                msr.lo |= 0x006f; /* 1.60V */
        msr_write(MSR_VR_MISC_CONFIG2, msr);

        /* Set C9/C10 VCC Min */
        pcode_mailbox_write(MAILBOX_BIOS_CMD_WRITE_C9C10_VOLTAGE, 0x1f1f);
}

static int calibrate_24mhz_bclk(void)
{
        int err_code;
        int ret;

        ret = pcode_ready();
        if (ret)
                return ret;

        /* A non-zero value initiates the PCODE calibration */
        writel(~0, MCHBAR_REG(BIOS_MAILBOX_DATA));
        writel(MAILBOX_RUN_BUSY | MAILBOX_BIOS_CMD_FSM_MEASURE_INTVL,
               MCHBAR_REG(BIOS_MAILBOX_INTERFACE));

        ret = pcode_ready();
        if (ret)
                return ret;

        err_code = readl(MCHBAR_REG(BIOS_MAILBOX_INTERFACE)) & 0xff;

        debug("PCODE: 24MHz BLCK calibration response: %d\n", err_code);

        /* Read the calibrated value */
        writel(MAILBOX_RUN_BUSY | MAILBOX_BIOS_CMD_READ_CALIBRATION,
               MCHBAR_REG(BIOS_MAILBOX_INTERFACE));

        ret = pcode_ready();
        if (ret)
                return ret;

        debug("PCODE: 24MHz BLCK calibration value: 0x%08x\n",
              readl(MCHBAR_REG(BIOS_MAILBOX_DATA)));

        return 0;
}

static void configure_pch_power_sharing(void)
{
        u32 pch_power, pch_power_ext, pmsync, pmsync2;
        int i;

        /* Read PCH Power levels from PCODE */
        pch_power = pcode_mailbox_read(MAILBOX_BIOS_CMD_READ_PCH_POWER);
        pch_power_ext = pcode_mailbox_read(MAILBOX_BIOS_CMD_READ_PCH_POWER_EXT);

        debug("PCH Power: PCODE Levels 0x%08x 0x%08x\n", pch_power,
              pch_power_ext);

        pmsync = readl(RCB_REG(PMSYNC_CONFIG));
        pmsync2 = readl(RCB_REG(PMSYNC_CONFIG2));

        /*
         * Program PMSYNC_TPR_CONFIG PCH power limit values
         *  pmsync[0:4]   = mailbox[0:5]
         *  pmsync[8:12]  = mailbox[6:11]
         *  pmsync[16:20] = mailbox[12:17]
         */
        for (i = 0; i < 3; i++) {
                u32 level = pch_power & 0x3f;
                pch_power >>= 6;
                pmsync &= ~(0x1f << (i * 8));
                pmsync |= (level & 0x1f) << (i * 8);
        }
        writel(pmsync, RCB_REG(PMSYNC_CONFIG));

        /*
         * Program PMSYNC_TPR_CONFIG2 Extended PCH power limit values
         *  pmsync2[0:4]   = mailbox[23:18]
         *  pmsync2[8:12]  = mailbox_ext[6:11]
         *  pmsync2[16:20] = mailbox_ext[12:17]
         *  pmsync2[24:28] = mailbox_ext[18:22]
         */
        pmsync2 &= ~0x1f;
        pmsync2 |= pch_power & 0x1f;

        for (i = 1; i < 4; i++) {
                u32 level = pch_power_ext & 0x3f;
                pch_power_ext >>= 6;
                pmsync2 &= ~(0x1f << (i * 8));
                pmsync2 |= (level & 0x1f) << (i * 8);
        }
        writel(pmsync2, RCB_REG(PMSYNC_CONFIG2));
}

static int bsp_init_before_ap_bringup(struct udevice *dev)
{
        int ret;

        initialize_vr_config(dev);
        ret = calibrate_24mhz_bclk();
        if (ret)
                return ret;
        configure_pch_power_sharing();

        return 0;
}

int cpu_config_tdp_levels(void)
{
        msr_t platform_info;

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

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

        perf_ctl.hi = 0;

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

        debug("cpu: frequency set to %d\n",
              ((perf_ctl.lo >> 8) & 0xff) * CPU_BCLK);
}

int broadwell_init(struct udevice *dev)
{
        struct cpu_broadwell_priv *priv = dev_get_priv(dev);
        int num_threads;
        int num_cores;
        msr_t msr;
        int ret;

        msr = msr_read(CORE_THREAD_COUNT_MSR);
        num_threads = (msr.lo >> 0) & 0xffff;
        num_cores = (msr.lo >> 16) & 0xffff;
        debug("CPU has %u cores, %u threads enabled\n", num_cores,
              num_threads);

        priv->ht_disabled = num_threads == num_cores;

        ret = bsp_init_before_ap_bringup(dev);
        if (ret)
                return ret;

        set_max_ratio();

        return ret;
}

static void configure_mca(void)
{
        msr_t msr;
        const unsigned int mcg_cap_msr = 0x179;
        int i;
        int num_banks;

        msr = msr_read(mcg_cap_msr);
        num_banks = msr.lo & 0xff;
        msr.lo = 0;
        msr.hi = 0;
        /*
         * TODO(adurbin): This should only be done on a cold boot. Also, some
         * of these banks are core vs package scope. For now every CPU clears
         * every bank
         */
        for (i = 0; i < num_banks; i++)
                msr_write(MSR_IA32_MC0_STATUS + (i * 4), msr);
}

static void enable_lapic_tpr(void)
{
        msr_t msr;

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


static void configure_c_states(void)
{
        msr_t msr;

        msr = msr_read(MSR_PMG_CST_CONFIG_CONTROL);
        msr.lo |= (1 << 31);    /* Timed MWAIT Enable */
        msr.lo |= (1 << 30);    /* Package c-state Undemotion Enable */
        msr.lo |= (1 << 29);    /* Package c-state Demotion Enable */
        msr.lo |= (1 << 28);    /* C1 Auto Undemotion Enable */
        msr.lo |= (1 << 27);    /* C3 Auto Undemotion Enable */
        msr.lo |= (1 << 26);    /* C1 Auto Demotion Enable */
        msr.lo |= (1 << 25);    /* C3 Auto Demotion Enable */
        msr.lo &= ~(1 << 10);   /* Disable IO MWAIT redirection */
        /* The deepest package c-state defaults to factory-configured value */
        msr_write(MSR_PMG_CST_CONFIG_CONTROL, msr);

        msr = msr_read(MSR_MISC_PWR_MGMT);
        msr.lo &= ~(1 << 0);    /* Enable P-state HW_ALL coordination */
        msr_write(MSR_MISC_PWR_MGMT, msr);

        msr = msr_read(MSR_POWER_CTL);
        msr.lo |= (1 << 18);    /* Enable Energy Perf Bias MSR 0x1b0 */
        msr.lo |= (1 << 1);     /* C1E Enable */
        msr.lo |= (1 << 0);     /* Bi-directional PROCHOT# */
        msr_write(MSR_POWER_CTL, msr);

        /* C-state Interrupt Response Latency Control 0 - package C3 latency */
        msr.hi = 0;
        msr.lo = IRTL_VALID | IRTL_1024_NS | C_STATE_LATENCY_CONTROL_0_LIMIT;
        msr_write(MSR_C_STATE_LATENCY_CONTROL_0, msr);

        /* C-state Interrupt Response Latency Control 1 */
        msr.hi = 0;
        msr.lo = IRTL_VALID | IRTL_1024_NS | C_STATE_LATENCY_CONTROL_1_LIMIT;
        msr_write(MSR_C_STATE_LATENCY_CONTROL_1, msr);

        /* C-state Interrupt Response Latency Control 2 - package C6/C7 short */
        msr.hi = 0;
        msr.lo = IRTL_VALID | IRTL_1024_NS | C_STATE_LATENCY_CONTROL_2_LIMIT;
        msr_write(MSR_C_STATE_LATENCY_CONTROL_2, msr);

        /* C-state Interrupt Response Latency Control 3 - package C8 */
        msr.hi = 0;
        msr.lo = IRTL_VALID | IRTL_1024_NS | C_STATE_LATENCY_CONTROL_3_LIMIT;
        msr_write(MSR_C_STATE_LATENCY_CONTROL_3, msr);

        /* C-state Interrupt Response Latency Control 4 - package C9 */
        msr.hi = 0;
        msr.lo = IRTL_VALID | IRTL_1024_NS | C_STATE_LATENCY_CONTROL_4_LIMIT;
        msr_write(MSR_C_STATE_LATENCY_CONTROL_4, msr);

        /* C-state Interrupt Response Latency Control 5 - package C10 */
        msr.hi = 0;
        msr.lo = IRTL_VALID | IRTL_1024_NS | C_STATE_LATENCY_CONTROL_5_LIMIT;
        msr_write(MSR_C_STATE_LATENCY_CONTROL_5, msr);
}

static void configure_misc(void)
{
        msr_t msr;

        msr = msr_read(MSR_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 */
        msr_write(MSR_IA32_MISC_ENABLE, msr);

        /* Disable thermal interrupts */
        msr.lo = 0;
        msr.hi = 0;
        msr_write(MSR_IA32_THERM_INTERRUPT, msr);

        /* Enable package critical interrupt only */
        msr.lo = 1 << 4;
        msr.hi = 0;
        msr_write(MSR_IA32_PACKAGE_THERM_INTERRUPT, msr);
}

static void configure_thermal_target(struct udevice *dev)
{
        int tcc_offset;
        msr_t msr;

        tcc_offset = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
                                    "intel,tcc-offset", 0);

        /* Set TCC activaiton offset if supported */
        msr = msr_read(MSR_PLATFORM_INFO);
        if ((msr.lo & (1 << 30)) && tcc_offset) {
                msr = msr_read(MSR_TEMPERATURE_TARGET);
                msr.lo &= ~(0xf << 24); /* Bits 27:24 */
                msr.lo |= (tcc_offset & 0xf) << 24;
                msr_write(MSR_TEMPERATURE_TARGET, msr);
        }
}

static void configure_dca_cap(void)
{
        struct cpuid_result cpuid_regs;
        msr_t msr;

        /* Check feature flag in CPUID.(EAX=1):ECX[18]==1 */
        cpuid_regs = cpuid(1);
        if (cpuid_regs.ecx & (1 << 18)) {
                msr = msr_read(MSR_IA32_PLATFORM_DCA_CAP);
                msr.lo |= 1;
                msr_write(MSR_IA32_PLATFORM_DCA_CAP, msr);
        }
}

static void set_energy_perf_bias(u8 policy)
{
        msr_t msr;
        int ecx;

        /* Determine if energy efficient policy is supported */
        ecx = cpuid_ecx(0x6);
        if (!(ecx & (1 << 3)))
                return;

        /* Energy Policy is bits 3:0 */
        msr = msr_read(MSR_IA32_ENERGY_PERFORMANCE_BIAS);
        msr.lo &= ~0xf;
        msr.lo |= policy & 0xf;
        msr_write(MSR_IA32_ENERGY_PERFORMANCE_BIAS, msr);

        debug("cpu: energy policy set to %u\n", policy);
}

/* All CPUs including BSP will run the following function */
static void cpu_core_init(struct udevice *dev)
{
        /* Clear out pending MCEs */
        configure_mca();

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

        /* Configure C States */
        configure_c_states();

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

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

        /* Enable Direct Cache Access */
        configure_dca_cap();

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

        /* Enable Turbo */
        turbo_enable();
}

/*
 * Configure processor power limits if possible
 * This must be done AFTER set of BIOS_RESET_CPL
 */
void cpu_set_power_limits(int power_limit_1_time)
{
        msr_t msr;
        msr_t limit;
        unsigned power_unit;
        unsigned tdp, min_power, max_power, max_time;
        u8 power_limit_1_val;

        msr = msr_read(MSR_PLATFORM_INFO);
        if (power_limit_1_time > ARRAY_SIZE(power_limit_time_sec_to_msr))
                power_limit_1_time = 28;

        if (!(msr.lo & PLATFORM_INFO_SET_TDP))
                return;

        /* Get units */
        msr = msr_read(MSR_PKG_POWER_SKU_UNIT);
        power_unit = 2 << ((msr.lo & 0xf) - 1);

        /* Get power defaults for this SKU */
        msr = msr_read(MSR_PKG_POWER_SKU);
        tdp = msr.lo & 0x7fff;
        min_power = (msr.lo >> 16) & 0x7fff;
        max_power = msr.hi & 0x7fff;
        max_time = (msr.hi >> 16) & 0x7f;

        debug("CPU TDP: %u Watts\n", tdp / power_unit);

        if (power_limit_time_msr_to_sec[max_time] > power_limit_1_time)
                power_limit_1_time = power_limit_time_msr_to_sec[max_time];

        if (min_power > 0 && tdp < min_power)
                tdp = min_power;

        if (max_power > 0 && tdp > max_power)
                tdp = max_power;

        power_limit_1_val = power_limit_time_sec_to_msr[power_limit_1_time];

        /* Set long term power limit to TDP */
        limit.lo = 0;
        limit.lo |= tdp & PKG_POWER_LIMIT_MASK;
        limit.lo |= PKG_POWER_LIMIT_EN;
        limit.lo |= (power_limit_1_val & PKG_POWER_LIMIT_TIME_MASK) <<
                PKG_POWER_LIMIT_TIME_SHIFT;

        /* Set short term power limit to 1.25 * TDP */
        limit.hi = 0;
        limit.hi |= ((tdp * 125) / 100) & PKG_POWER_LIMIT_MASK;
        limit.hi |= PKG_POWER_LIMIT_EN;
        /* Power limit 2 time is only programmable on server SKU */

        msr_write(MSR_PKG_POWER_LIMIT, limit);

        /* Set power limit values in MCHBAR as well */
        writel(limit.lo, MCHBAR_REG(MCH_PKG_POWER_LIMIT_LO));
        writel(limit.hi, MCHBAR_REG(MCH_PKG_POWER_LIMIT_HI));

        /* Set DDR RAPL power limit by copying from MMIO to MSR */
        msr.lo = readl(MCHBAR_REG(MCH_DDR_POWER_LIMIT_LO));
        msr.hi = readl(MCHBAR_REG(MCH_DDR_POWER_LIMIT_HI));
        msr_write(MSR_DDR_RAPL_LIMIT, msr);

        /* Use nominal TDP values for CPUs with configurable TDP */
        if (cpu_config_tdp_levels()) {
                msr = msr_read(MSR_CONFIG_TDP_NOMINAL);
                limit.hi = 0;
                limit.lo = msr.lo & 0xff;
                msr_write(MSR_TURBO_ACTIVATION_RATIO, limit);
        }
}

static int broadwell_get_info(struct udevice *dev, struct cpu_info *info)
{
        msr_t msr;

        msr = msr_read(IA32_PERF_CTL);
        info->cpu_freq = ((msr.lo >> 8) & 0xff) * BROADWELL_BCLK * 1000000;
        info->features = 1 << CPU_FEAT_L1_CACHE | 1 << CPU_FEAT_MMU |
                1 << CPU_FEAT_UCODE | 1 << CPU_FEAT_DEVICE_ID;

        return 0;
}

static int broadwell_get_count(struct udevice *dev)
{
        return 4;
}

static int cpu_x86_broadwell_probe(struct udevice *dev)
{
        if (dev->seq == 0) {
                cpu_core_init(dev);
                return broadwell_init(dev);
        }

        return 0;
}

static const struct cpu_ops cpu_x86_broadwell_ops = {
        .get_desc       = cpu_x86_get_desc,
        .get_info       = broadwell_get_info,
        .get_count      = broadwell_get_count,
        .get_vendor     = cpu_x86_get_vendor,
};

static const struct udevice_id cpu_x86_broadwell_ids[] = {
        { .compatible = "intel,core-i3-gen5" },
        { }
};

U_BOOT_DRIVER(cpu_x86_broadwell_drv) = {
        .name           = "cpu_x86_broadwell",
        .id             = UCLASS_CPU,
        .of_match       = cpu_x86_broadwell_ids,
        .bind           = cpu_x86_bind,
        .probe          = cpu_x86_broadwell_probe,
        .ops            = &cpu_x86_broadwell_ops,
        .priv_auto_alloc_size   = sizeof(struct cpu_broadwell_priv),
};