/*
 * Copyright 2020, Data61, CSIRO (ABN 41 687 119 230)
 *
 * SPDX-License-Identifier: GPL-2.0-only
 */

#pragma once

#include <printf.h>
#include <types.h>

typedef union {
    uint8_t b[16];
    struct {
        uint32_t timeLow;
        uint16_t timeMid;
        uint16_t timeHigh;
        uint8_t clockSeqHighAndReserved;
        uint8_t clockSeqLow;
        uint8_t node[6];
    } s;
} efi_guid_t;

/* See UEFI Spec v2.7 Appendix A "GUID and Time Formats". */
static inline efi_guid_t make_efi_guid(uint32_t timeLow, uint16_t timeMid, uint16_t timeHighAndVersion,
        uint8_t clockSeqHighAndReserved, uint8_t clockSeqLow, uint8_t n0,
        uint8_t n1, uint8_t n2, uint8_t n3, uint8_t n4, uint8_t n5)
{
    efi_guid_t u;
    u.s.timeLow = timeLow;
    u.s.timeMid = timeMid;
    u.s.timeHigh = timeHighAndVersion;
    u.s.clockSeqHighAndReserved = clockSeqHighAndReserved;
    u.s.clockSeqLow = clockSeqLow;
    u.s.node[0] = n0;
    u.s.node[1] = n1;
    u.s.node[2] = n2;
    u.s.node[3] = n3;
    u.s.node[4] = n4;
    u.s.node[5] = n5;
    return u;
}

typedef struct {
    efi_guid_t guid;
    uintptr_t table;
} efi_config_table_t;

typedef struct {
    uint64_t signature;
    uint32_t revision;
    uint32_t headersize;
    uint32_t crc32;
    uint32_t reserved;
} efi_table_hdr_t;

typedef struct {
    efi_table_hdr_t hdr;
    void *fw_vendor;
    uint32_t fw_revision;
    /* padding on 64-bit */
    void *con_in_handle;
    void *con_in;
    void *con_out_handle;
    void *con_out;
    void *stderr_handle;
    void *stderr;
    void *runtime;
    void *boottime;
    uint32_t nr_tables;
    /* padding on 64-bit */
    void *tables;
} efi_system_table_t;

extern void *__application_handle;
extern efi_system_table_t *__efi_system_table;

/* Errors have the highest bit set. */
#define EFI_ERROR_FLAG                  (~(WORD_MAX >> 1))

#define EFI_SUCCESS                     0
#define EFI_LOAD_ERROR                  (1 | EFI_ERROR_FLAG)
#define EFI_BUFFER_TOO_SMALL            (5 | EFI_ERROR_FLAG)

/* EFI Memory types: */
#define EFI_RESERVED_TYPE                0
#define EFI_LOADER_CODE                  1
#define EFI_LOADER_DATA                  2
#define EFI_BOOT_SERVICES_CODE           3
#define EFI_BOOT_SERVICES_DATA           4
#define EFI_RUNTIME_SERVICES_CODE        5
#define EFI_RUNTIME_SERVICES_DATA        6
#define EFI_CONVENTIONAL_MEMORY          7
#define EFI_UNUSABLE_MEMORY              8
#define EFI_ACPI_RECLAIM_MEMORY          9
#define EFI_ACPI_MEMORY_NVS             10
#define EFI_MEMORY_MAPPED_IO            11
#define EFI_MEMORY_MAPPED_IO_PORT_SPACE 12
#define EFI_PAL_CODE                    13
#define EFI_PERSISTENT_MEMORY           14
#define EFI_MAX_MEMORY_TYPE             15

/* Attribute values: */
#define EFI_MEMORY_UC                   (UINT64_C(1) << 0)    /* uncached */
#define EFI_MEMORY_WC                   (UINT64_C(1) << 1)    /* write-coalescing */
#define EFI_MEMORY_WT                   (UINT64_C(1) << 2)    /* write-through */
#define EFI_MEMORY_WB                   (UINT64_C(1) << 3)    /* write-back */
#define EFI_MEMORY_UCE                  (UINT64_C(1) << 4)    /* uncached, exported */
#define EFI_MEMORY_WP                   (UINT64_C(1) << 12)   /* write-protect */
#define EFI_MEMORY_RP                   (UINT64_C(1) << 13)   /* read-protect */
#define EFI_MEMORY_XP                   (UINT64_C(1) << 14)   /* execute-protect */
#define EFI_MEMORY_MORE_RELIABLE        (UINT64_C(1) << 16)   /* higher reliability */
#define EFI_MEMORY_RO                   (UINT64_C(1) << 17)   /* read-only */
#define EFI_MEMORY_RUNTIME              (UINT64_C(1) << 31)   /* range requires runtime mapping */
#define EFI_MEMORY_DESCRIPTOR_VERSION   1

#define EFI_PAGE_BITS                   12
#define EFI_PAGE_SIZE                   (1UL << EFI_PAGE_BITS)

typedef struct {
    uint32_t type;
    uint32_t padding_1;
    uint64_t phys_addr;
    uint64_t virt_addr;
    uint64_t num_pages;
    uint64_t attribute;
} efi_memory_desc_t;

typedef struct {
    efi_table_hdr_t hdr;
    uintptr_t padding_1[4];
    unsigned long (*get_memory_map)(unsigned long *, void *, unsigned long *, unsigned long *, uint32_t *);
    unsigned long (*allocate_pool)(int, unsigned long, void **);
    unsigned long (*free_pool)(void *);
    uintptr_t padding_2[19];
    unsigned long (*exit_boot_services)(void *, unsigned long);
    uintptr_t padding_3[17];
} efi_boot_services_t;

int efi_guideq(efi_guid_t a, efi_guid_t b);
efi_boot_services_t *get_efi_boot_services(void);

void efi_early_init(uintptr_t application_handle, uintptr_t efi_system_table);
unsigned long efi_exit_boot_services(void);
void *efi_get_fdt(void);