/*
 * (C) Copyright 2008-2011
 * Graeme Russ, <graeme.russ@gmail.com>
 *
 * (C) Copyright 2002
 * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
 *
 * (C) Copyright 2002
 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Marius Groeger <mgroeger@sysgo.de>
 *
 * (C) Copyright 2002
 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Alex Zuepke <azu@sysgo.de>
 *
 * Part of this file is adapted from coreboot
 * src/arch/x86/lib/cpu.c
 *
 * SPDX-License-Identifier:     GPL-2.0+
 */

#include <common.h>
#include <command.h>
#include <dm.h>
#include <errno.h>
#include <malloc.h>
#include <asm/control_regs.h>
#include <asm/cpu.h>
#include <asm/lapic.h>
#include <asm/mp.h>
#include <asm/msr.h>
#include <asm/mtrr.h>
#include <asm/post.h>
#include <asm/processor.h>
#include <asm/processor-flags.h>
#include <asm/interrupt.h>
#include <asm/tables.h>
#include <linux/compiler.h>

DECLARE_GLOBAL_DATA_PTR;

/*
 * Constructor for a conventional segment GDT (or LDT) entry
 * This is a macro so it can be used in initialisers
 */
#define GDT_ENTRY(flags, base, limit)                   \
        ((((base)  & 0xff000000ULL) << (56-24)) |       \
         (((flags) & 0x0000f0ffULL) << 40) |            \
         (((limit) & 0x000f0000ULL) << (48-16)) |       \
         (((base)  & 0x00ffffffULL) << 16) |            \
         (((limit) & 0x0000ffffULL)))

struct gdt_ptr {
        u16 len;
        u32 ptr;
} __packed;

struct cpu_device_id {
        unsigned vendor;
        unsigned device;
};

struct cpuinfo_x86 {
        uint8_t x86;            /* CPU family */
        uint8_t x86_vendor;     /* CPU vendor */
        uint8_t x86_model;
        uint8_t x86_mask;
};

/*
 * List of cpu vendor strings along with their normalized
 * id values.
 */
static struct {
        int vendor;
        const char *name;
} x86_vendors[] = {
        { X86_VENDOR_INTEL,     "GenuineIntel", },
        { X86_VENDOR_CYRIX,     "CyrixInstead", },
        { X86_VENDOR_AMD,       "AuthenticAMD", },
        { X86_VENDOR_UMC,       "UMC UMC UMC ", },
        { X86_VENDOR_NEXGEN,    "NexGenDriven", },
        { X86_VENDOR_CENTAUR,   "CentaurHauls", },
        { X86_VENDOR_RISE,      "RiseRiseRise", },
        { X86_VENDOR_TRANSMETA, "GenuineTMx86", },
        { X86_VENDOR_TRANSMETA, "TransmetaCPU", },
        { X86_VENDOR_NSC,       "Geode by NSC", },
        { X86_VENDOR_SIS,       "SiS SiS SiS ", },
};

static const char *const x86_vendor_name[] = {
        [X86_VENDOR_INTEL]     = "Intel",
        [X86_VENDOR_CYRIX]     = "Cyrix",
        [X86_VENDOR_AMD]       = "AMD",
        [X86_VENDOR_UMC]       = "UMC",
        [X86_VENDOR_NEXGEN]    = "NexGen",
        [X86_VENDOR_CENTAUR]   = "Centaur",
        [X86_VENDOR_RISE]      = "Rise",
        [X86_VENDOR_TRANSMETA] = "Transmeta",
        [X86_VENDOR_NSC]       = "NSC",
        [X86_VENDOR_SIS]       = "SiS",
};

static void load_ds(u32 segment)
{
        asm volatile("movl %0, %%ds" : : "r" (segment * X86_GDT_ENTRY_SIZE));
}

static void load_es(u32 segment)
{
        asm volatile("movl %0, %%es" : : "r" (segment * X86_GDT_ENTRY_SIZE));
}

static void load_fs(u32 segment)
{
        asm volatile("movl %0, %%fs" : : "r" (segment * X86_GDT_ENTRY_SIZE));
}

static void load_gs(u32 segment)
{
        asm volatile("movl %0, %%gs" : : "r" (segment * X86_GDT_ENTRY_SIZE));
}

static void load_ss(u32 segment)
{
        asm volatile("movl %0, %%ss" : : "r" (segment * X86_GDT_ENTRY_SIZE));
}

static void load_gdt(const u64 *boot_gdt, u16 num_entries)
{
        struct gdt_ptr gdt;

        gdt.len = (num_entries * X86_GDT_ENTRY_SIZE) - 1;
        gdt.ptr = (u32)boot_gdt;

        asm volatile("lgdtl %0\n" : : "m" (gdt));
}

void arch_setup_gd(gd_t *new_gd)
{
        u64 *gdt_addr;

        gdt_addr = new_gd->arch.gdt;

        /* CS: code, read/execute, 4 GB, base 0 */
        gdt_addr[X86_GDT_ENTRY_32BIT_CS] = GDT_ENTRY(0xc09b, 0, 0xfffff);

        /* DS: data, read/write, 4 GB, base 0 */
        gdt_addr[X86_GDT_ENTRY_32BIT_DS] = GDT_ENTRY(0xc093, 0, 0xfffff);

        /* FS: data, read/write, 4 GB, base (Global Data Pointer) */
        new_gd->arch.gd_addr = new_gd;
        gdt_addr[X86_GDT_ENTRY_32BIT_FS] = GDT_ENTRY(0xc093,
                     (ulong)&new_gd->arch.gd_addr, 0xfffff);

        /* 16-bit CS: code, read/execute, 64 kB, base 0 */
        gdt_addr[X86_GDT_ENTRY_16BIT_CS] = GDT_ENTRY(0x009b, 0, 0x0ffff);

        /* 16-bit DS: data, read/write, 64 kB, base 0 */
        gdt_addr[X86_GDT_ENTRY_16BIT_DS] = GDT_ENTRY(0x0093, 0, 0x0ffff);

        gdt_addr[X86_GDT_ENTRY_16BIT_FLAT_CS] = GDT_ENTRY(0x809b, 0, 0xfffff);
        gdt_addr[X86_GDT_ENTRY_16BIT_FLAT_DS] = GDT_ENTRY(0x8093, 0, 0xfffff);

        load_gdt(gdt_addr, X86_GDT_NUM_ENTRIES);
        load_ds(X86_GDT_ENTRY_32BIT_DS);
        load_es(X86_GDT_ENTRY_32BIT_DS);
        load_gs(X86_GDT_ENTRY_32BIT_DS);
        load_ss(X86_GDT_ENTRY_32BIT_DS);
        load_fs(X86_GDT_ENTRY_32BIT_FS);
}

#ifdef CONFIG_HAVE_FSP
/*
 * Setup FSP execution environment GDT
 *
 * Per Intel FSP external architecture specification, before calling any FSP
 * APIs, we need make sure the system is in flat 32-bit mode and both the code
 * and data selectors should have full 4GB access range. Here we reuse the one
 * we used in arch/x86/cpu/start16.S, and reload the segement registers.
 */
void setup_fsp_gdt(void)
{
        load_gdt((const u64 *)(gdt_rom + CONFIG_RESET_SEG_START), 4);
        load_ds(X86_GDT_ENTRY_32BIT_DS);
        load_ss(X86_GDT_ENTRY_32BIT_DS);
        load_es(X86_GDT_ENTRY_32BIT_DS);
        load_fs(X86_GDT_ENTRY_32BIT_DS);
        load_gs(X86_GDT_ENTRY_32BIT_DS);
}
#endif

int __weak x86_cleanup_before_linux(void)
{
#ifdef CONFIG_BOOTSTAGE_STASH
        bootstage_stash((void *)CONFIG_BOOTSTAGE_STASH_ADDR,
                        CONFIG_BOOTSTAGE_STASH_SIZE);
#endif

        return 0;
}

/*
 * Cyrix CPUs without cpuid or with cpuid not yet enabled can be detected
 * by the fact that they preserve the flags across the division of 5/2.
 * PII and PPro exhibit this behavior too, but they have cpuid available.
 */

/*
 * Perform the Cyrix 5/2 test. A Cyrix won't change
 * the flags, while other 486 chips will.
 */
static inline int test_cyrix_52div(void)
{
        unsigned int test;

        __asm__ __volatile__(
             "sahf\n\t"         /* clear flags (%eax = 0x0005) */
             "div %b2\n\t"      /* divide 5 by 2 */
             "lahf"             /* store flags into %ah */
             : "=a" (test)
             : "0" (5), "q" (2)
             : "cc");

        /* AH is 0x02 on Cyrix after the divide.. */
        return (unsigned char) (test >> 8) == 0x02;
}

/*
 *      Detect a NexGen CPU running without BIOS hypercode new enough
 *      to have CPUID. (Thanks to Herbert Oppmann)
 */

static int deep_magic_nexgen_probe(void)
{
        int ret;

        __asm__ __volatile__ (
                "       movw    $0x5555, %%ax\n"
                "       xorw    %%dx,%%dx\n"
                "       movw    $2, %%cx\n"
                "       divw    %%cx\n"
                "       movl    $0, %%eax\n"
                "       jnz     1f\n"
                "       movl    $1, %%eax\n"
                "1:\n"
                : "=a" (ret) : : "cx", "dx");
        return  ret;
}

static bool has_cpuid(void)
{
        return flag_is_changeable_p(X86_EFLAGS_ID);
}

static bool has_mtrr(void)
{
        return cpuid_edx(0x00000001) & (1 << 12) ? true : false;
}

static int build_vendor_name(char *vendor_name)
{
        struct cpuid_result result;
        result = cpuid(0x00000000);
        unsigned int *name_as_ints = (unsigned int *)vendor_name;

        name_as_ints[0] = result.ebx;
        name_as_ints[1] = result.edx;
        name_as_ints[2] = result.ecx;

        return result.eax;
}

static void identify_cpu(struct cpu_device_id *cpu)
{
        char vendor_name[16];
        int i;

        vendor_name[0] = '\0'; /* Unset */
        cpu->device = 0; /* fix gcc 4.4.4 warning */

        /* Find the id and vendor_name */
        if (!has_cpuid()) {
                /* Its a 486 if we can modify the AC flag */
                if (flag_is_changeable_p(X86_EFLAGS_AC))
                        cpu->device = 0x00000400; /* 486 */
                else
                        cpu->device = 0x00000300; /* 386 */
                if ((cpu->device == 0x00000400) && test_cyrix_52div()) {
                        memcpy(vendor_name, "CyrixInstead", 13);
                        /* If we ever care we can enable cpuid here */
                }
                /* Detect NexGen with old hypercode */
                else if (deep_magic_nexgen_probe())
                        memcpy(vendor_name, "NexGenDriven", 13);
        }
        if (has_cpuid()) {
                int  cpuid_level;

                cpuid_level = build_vendor_name(vendor_name);
                vendor_name[12] = '\0';

                /* Intel-defined flags: level 0x00000001 */
                if (cpuid_level >= 0x00000001) {
                        cpu->device = cpuid_eax(0x00000001);
                } else {
                        /* Have CPUID level 0 only unheard of */
                        cpu->device = 0x00000400;
                }
        }
        cpu->vendor = X86_VENDOR_UNKNOWN;
        for (i = 0; i < ARRAY_SIZE(x86_vendors); i++) {
                if (memcmp(vendor_name, x86_vendors[i].name, 12) == 0) {
                        cpu->vendor = x86_vendors[i].vendor;
                        break;
                }
        }
}

static inline void get_fms(struct cpuinfo_x86 *c, uint32_t tfms)
{
        c->x86 = (tfms >> 8) & 0xf;
        c->x86_model = (tfms >> 4) & 0xf;
        c->x86_mask = tfms & 0xf;
        if (c->x86 == 0xf)
                c->x86 += (tfms >> 20) & 0xff;
        if (c->x86 >= 0x6)
                c->x86_model += ((tfms >> 16) & 0xF) << 4;
}

int x86_cpu_init_f(void)
{
        const u32 em_rst = ~X86_CR0_EM;
        const u32 mp_ne_set = X86_CR0_MP | X86_CR0_NE;

        if (ll_boot_init()) {
                /* initialize FPU, reset EM, set MP and NE */
                asm ("fninit\n" \
                "movl %%cr0, %%eax\n" \
                "andl %0, %%eax\n" \
                "orl  %1, %%eax\n" \
                "movl %%eax, %%cr0\n" \
                : : "i" (em_rst), "i" (mp_ne_set) : "eax");
        }

        /* identify CPU via cpuid and store the decoded info into gd->arch */
        if (has_cpuid()) {
                struct cpu_device_id cpu;
                struct cpuinfo_x86 c;

                identify_cpu(&cpu);
                get_fms(&c, cpu.device);
                gd->arch.x86 = c.x86;
                gd->arch.x86_vendor = cpu.vendor;
                gd->arch.x86_model = c.x86_model;
                gd->arch.x86_mask = c.x86_mask;
                gd->arch.x86_device = cpu.device;

                gd->arch.has_mtrr = has_mtrr();
        }
        /* Don't allow PCI region 3 to use memory in the 2-4GB memory hole */
        gd->pci_ram_top = 0x80000000U;

        /* Configure fixed range MTRRs for some legacy regions */
        if (gd->arch.has_mtrr) {
                u64 mtrr_cap;

                mtrr_cap = native_read_msr(MTRR_CAP_MSR);
                if (mtrr_cap & MTRR_CAP_FIX) {
                        /* Mark the VGA RAM area as uncacheable */
                        native_write_msr(MTRR_FIX_16K_A0000_MSR,
                                         MTRR_FIX_TYPE(MTRR_TYPE_UNCACHEABLE),
                                         MTRR_FIX_TYPE(MTRR_TYPE_UNCACHEABLE));

                        /*
                         * Mark the PCI ROM area as cacheable to improve ROM
                         * execution performance.
                         */
                        native_write_msr(MTRR_FIX_4K_C0000_MSR,
                                         MTRR_FIX_TYPE(MTRR_TYPE_WRBACK),
                                         MTRR_FIX_TYPE(MTRR_TYPE_WRBACK));
                        native_write_msr(MTRR_FIX_4K_C8000_MSR,
                                         MTRR_FIX_TYPE(MTRR_TYPE_WRBACK),
                                         MTRR_FIX_TYPE(MTRR_TYPE_WRBACK));
                        native_write_msr(MTRR_FIX_4K_D0000_MSR,
                                         MTRR_FIX_TYPE(MTRR_TYPE_WRBACK),
                                         MTRR_FIX_TYPE(MTRR_TYPE_WRBACK));
                        native_write_msr(MTRR_FIX_4K_D8000_MSR,
                                         MTRR_FIX_TYPE(MTRR_TYPE_WRBACK),
                                         MTRR_FIX_TYPE(MTRR_TYPE_WRBACK));

                        /* Enable the fixed range MTRRs */
                        msr_setbits_64(MTRR_DEF_TYPE_MSR, MTRR_DEF_TYPE_FIX_EN);
                }
        }

        return 0;
}

void x86_enable_caches(void)
{
        unsigned long cr0;

        cr0 = read_cr0();
        cr0 &= ~(X86_CR0_NW | X86_CR0_CD);
        write_cr0(cr0);
        wbinvd();
}
void enable_caches(void) __attribute__((weak, alias("x86_enable_caches")));

void x86_disable_caches(void)
{
        unsigned long cr0;

        cr0 = read_cr0();
        cr0 |= X86_CR0_NW | X86_CR0_CD;
        wbinvd();
        write_cr0(cr0);
        wbinvd();
}
void disable_caches(void) __attribute__((weak, alias("x86_disable_caches")));

int x86_init_cache(void)
{
        enable_caches();

        return 0;
}
int init_cache(void) __attribute__((weak, alias("x86_init_cache")));

int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
        printf("resetting ...\n");

        /* wait 50 ms */
        udelay(50000);
        disable_interrupts();
        reset_cpu(0);

        /*NOTREACHED*/
        return 0;
}

void  flush_cache(unsigned long dummy1, unsigned long dummy2)
{
        asm("wbinvd\n");
}

__weak void reset_cpu(ulong addr)
{
        /* Do a hard reset through the chipset's reset control register */
        outb(SYS_RST | RST_CPU, PORT_RESET);
        for (;;)
                cpu_hlt();
}

void x86_full_reset(void)
{
        outb(FULL_RST | SYS_RST | RST_CPU, PORT_RESET);
}

int dcache_status(void)
{
        return !(read_cr0() & X86_CR0_CD);
}

/* Define these functions to allow ehch-hcd to function */
void flush_dcache_range(unsigned long start, unsigned long stop)
{
}

void invalidate_dcache_range(unsigned long start, unsigned long stop)
{
}

void dcache_enable(void)
{
        enable_caches();
}

void dcache_disable(void)
{
        disable_caches();
}

void icache_enable(void)
{
}

void icache_disable(void)
{
}

int icache_status(void)
{
        return 1;
}

void cpu_enable_paging_pae(ulong cr3)
{
        __asm__ __volatile__(
                /* Load the page table address */
                "movl   %0, %%cr3\n"
                /* Enable pae */
                "movl   %%cr4, %%eax\n"
                "orl    $0x00000020, %%eax\n"
                "movl   %%eax, %%cr4\n"
                /* Enable paging */
                "movl   %%cr0, %%eax\n"
                "orl    $0x80000000, %%eax\n"
                "movl   %%eax, %%cr0\n"
                :
                : "r" (cr3)
                : "eax");
}

void cpu_disable_paging_pae(void)
{
        /* Turn off paging */
        __asm__ __volatile__ (
                /* Disable paging */
                "movl   %%cr0, %%eax\n"
                "andl   $0x7fffffff, %%eax\n"
                "movl   %%eax, %%cr0\n"
                /* Disable pae */
                "movl   %%cr4, %%eax\n"
                "andl   $0xffffffdf, %%eax\n"
                "movl   %%eax, %%cr4\n"
                :
                :
                : "eax");
}

static bool can_detect_long_mode(void)
{
        return cpuid_eax(0x80000000) > 0x80000000UL;
}

static bool has_long_mode(void)
{
        return cpuid_edx(0x80000001) & (1 << 29) ? true : false;
}

int cpu_has_64bit(void)
{
        return has_cpuid() && can_detect_long_mode() &&
                has_long_mode();
}

const char *cpu_vendor_name(int vendor)
{
        const char *name;
        name = "<invalid cpu vendor>";
        if ((vendor < (ARRAY_SIZE(x86_vendor_name))) &&
            (x86_vendor_name[vendor] != 0))
                name = x86_vendor_name[vendor];

        return name;
}

char *cpu_get_name(char *name)
{
        unsigned int *name_as_ints = (unsigned int *)name;
        struct cpuid_result regs;
        char *ptr;
        int i;

        /* This bit adds up to 48 bytes */
        for (i = 0; i < 3; i++) {
                regs = cpuid(0x80000002 + i);
                name_as_ints[i * 4 + 0] = regs.eax;
                name_as_ints[i * 4 + 1] = regs.ebx;
                name_as_ints[i * 4 + 2] = regs.ecx;
                name_as_ints[i * 4 + 3] = regs.edx;
        }
        name[CPU_MAX_NAME_LEN - 1] = '\0';

        /* Skip leading spaces. */
        ptr = name;
        while (*ptr == ' ')
                ptr++;

        return ptr;
}

int default_print_cpuinfo(void)
{
        printf("CPU: %s, vendor %s, device %xh\n",
               cpu_has_64bit() ? "x86_64" : "x86",
               cpu_vendor_name(gd->arch.x86_vendor), gd->arch.x86_device);

        return 0;
}

#define PAGETABLE_SIZE          (6 * 4096)

/**
 * build_pagetable() - build a flat 4GiB page table structure for 64-bti mode
 *
 * @pgtable: Pointer to a 24iKB block of memory
 */
static void build_pagetable(uint32_t *pgtable)
{
        uint i;

        memset(pgtable, '\0', PAGETABLE_SIZE);

        /* Level 4 needs a single entry */
        pgtable[0] = (uint32_t)&pgtable[1024] + 7;

        /* Level 3 has one 64-bit entry for each GiB of memory */
        for (i = 0; i < 4; i++) {
                pgtable[1024 + i * 2] = (uint32_t)&pgtable[2048] +
                                                        0x1000 * i + 7;
        }

        /* Level 2 has 2048 64-bit entries, each repesenting 2MiB */
        for (i = 0; i < 2048; i++)
                pgtable[2048 + i * 2] = 0x183 + (i << 21UL);
}

int cpu_jump_to_64bit(ulong setup_base, ulong target)
{
        uint32_t *pgtable;

        pgtable = memalign(4096, PAGETABLE_SIZE);
        if (!pgtable)
                return -ENOMEM;

        build_pagetable(pgtable);
        cpu_call64((ulong)pgtable, setup_base, target);
        free(pgtable);

        return -EFAULT;
}

void show_boot_progress(int val)
{
#if MIN_PORT80_KCLOCKS_DELAY
        /*
         * Scale the time counter reading to avoid using 64 bit arithmetics.
         * Can't use get_timer() here becuase it could be not yet
         * initialized or even implemented.
         */
        if (!gd->arch.tsc_prev) {
                gd->arch.tsc_base_kclocks = rdtsc() / 1000;
                gd->arch.tsc_prev = 0;
        } else {
                uint32_t now;

                do {
                        now = rdtsc() / 1000 - gd->arch.tsc_base_kclocks;
                } while (now < (gd->arch.tsc_prev + MIN_PORT80_KCLOCKS_DELAY));
                gd->arch.tsc_prev = now;
        }
#endif
        outb(val, POST_PORT);
}

#ifndef CONFIG_SYS_COREBOOT
int last_stage_init(void)
{
        write_tables();

        return 0;
}
#endif

#ifdef CONFIG_SMP
static int enable_smis(struct udevice *cpu, void *unused)
{
        return 0;
}

static struct mp_flight_record mp_steps[] = {
        MP_FR_BLOCK_APS(mp_init_cpu, NULL, mp_init_cpu, NULL),
        /* Wait for APs to finish initialization before proceeding */
        MP_FR_BLOCK_APS(NULL, NULL, enable_smis, NULL),
};

static int x86_mp_init(void)
{
        struct mp_params mp_params;

        mp_params.parallel_microcode_load = 0,
        mp_params.flight_plan = &mp_steps[0];
        mp_params.num_records = ARRAY_SIZE(mp_steps);
        mp_params.microcode_pointer = 0;

        if (mp_init(&mp_params)) {
                printf("Warning: MP init failure\n");
                return -EIO;
        }

        return 0;
}
#endif

__weak int x86_init_cpus(void)
{
#ifdef CONFIG_SMP
        debug("Init additional CPUs\n");
        x86_mp_init();
#else
        struct udevice *dev;

        /*
         * This causes the cpu-x86 driver to be probed.
         * We don't check return value here as we want to allow boards
         * which have not been converted to use cpu uclass driver to boot.
         */
        uclass_first_device(UCLASS_CPU, &dev);
#endif

        return 0;
}

int cpu_init_r(void)
{
        if (ll_boot_init())
                return x86_init_cpus();

        return 0;
}