// SPDX-License-Identifier: GPL-2.0
/*
 * Author: Huacai Chen <chenhuacai@loongson.cn>
 * Copyright (C) 2020 Loongson Technology Corporation Limited
 */

#include <linux/acpi.h>
#include <linux/dmi.h>
#include <linux/efi.h>
#include <linux/memblock.h>
#include <asm/acpi.h>
#include <asm/bootinfo.h>
#include <asm/cacheflush.h>
#include <asm/efi.h>
#include <asm/smp.h>
#include <asm/time.h>

#include <loongson.h>

#define SMBIOS_BIOSSIZE_OFFSET		0x09
#define SMBIOS_BIOSEXTERN_OFFSET 	0x13
#define SMBIOS_FREQLOW_OFFSET		0x16
#define SMBIOS_FREQHIGH_OFFSET		0x17
#define SMBIOS_FREQLOW_MASK		0xFF
#define SMBIOS_CORE_PACKAGE_OFFSET	0x23
#define LOONGSON_EFI_ENABLE     	(1 << 3)

struct loongson_board_info b_info;
static const char dmi_empty_string[] = "        ";
extern void __init arch_reserve_vmcore(void);
extern void __init arch_parse_crashkernel(void);

static const char *dmi_string_parse(const struct dmi_header *dm, u8 s)
{
	const u8 *bp = ((u8 *) dm) + dm->length;

	if (s) {
		s--;
		while (s > 0 && *bp) {
			bp += strlen(bp) + 1;
			s--;
		}

		if (*bp != 0) {
			size_t len = strlen(bp)+1;
			size_t cmp_len = len > 8 ? 8 : len;

			if (!memcmp(bp, dmi_empty_string, cmp_len))
				return dmi_empty_string;

			return bp;
		}
	}

	return "";

}

static void __init parse_cpu_table(const struct dmi_header *dm)
{
	long freq_temp = 0;
	char *dmi_data = (char *)dm;

	freq_temp = ((*(dmi_data + SMBIOS_FREQHIGH_OFFSET) << 8) + \
			((*(dmi_data + SMBIOS_FREQLOW_OFFSET)) & SMBIOS_FREQLOW_MASK));
	cpu_clock_freq = freq_temp * 1000000;

	loongson_sysconf.cpuname = (void *)dmi_string_parse(dm, dmi_data[16]);
	loongson_sysconf.cores_per_package = *(dmi_data + SMBIOS_CORE_PACKAGE_OFFSET);

	pr_info("CpuClock = %llu\n", cpu_clock_freq);

}

static void __init parse_bios_table(const struct dmi_header *dm)
{
	char *dmi_data = (char *)dm;

	b_info.bios_size = (*(dmi_data + SMBIOS_BIOSSIZE_OFFSET) + 1) << 6;
}

static void __init find_tokens(const struct dmi_header *dm, void *dummy)
{
	switch (dm->type) {
	case 0x0: /* Extern BIOS */
		parse_bios_table(dm);
		break;
	case 0x4: /* Calling interface */
		parse_cpu_table(dm);
		break;
	}
}

static void __init smbios_parse(void)
{
	b_info.bios_vendor = (void *)dmi_get_system_info(DMI_BIOS_VENDOR);
	b_info.bios_version = (void *)dmi_get_system_info(DMI_BIOS_VERSION);
	b_info.bios_release_date = (void *)dmi_get_system_info(DMI_BIOS_DATE);
	b_info.board_vendor = (void *)dmi_get_system_info(DMI_BOARD_VENDOR);
	b_info.board_name = (void *)dmi_get_system_info(DMI_BOARD_NAME);
	dmi_walk(find_tokens, NULL);
}

void __init early_init(void)
{
	init_environ();
	efi_init();
	memblock_init();
}

void __init platform_init(void)
{
	arch_reserve_vmcore();
	arch_parse_crashkernel();

#ifdef CONFIG_ACPI_TABLE_UPGRADE
	acpi_table_upgrade();
#endif
#ifdef CONFIG_ACPI
	acpi_gbl_use_default_register_widths = false;
	acpi_boot_table_init();
#endif

#ifdef CONFIG_NUMA
	init_numa_memory();
#endif
	dmi_setup();
	smbios_parse();
	pr_info("The BIOS Version: %s\n",b_info.bios_version);

	efi_runtime_init();

	register_smp_ops(&loongson3_smp_ops);
}