// SPDX-License-Identifier: GPL-2.0+
/*
 *  EFI application console interface
 *
 *  Copyright (c) 2016 Alexander Graf
 */

#include <common.h>
#include <charset.h>
#include <malloc.h>
#include <time.h>
#include <dm/device.h>
#include <efi_loader.h>
#include <env.h>
#include <stdio_dev.h>
#include <video_console.h>
#include <linux/delay.h>

#define EFI_COUT_MODE_2 2
#define EFI_MAX_COUT_MODE 3

struct cout_mode {
        unsigned long columns;
        unsigned long rows;
        int present;
};

static struct cout_mode efi_cout_modes[] = {
        /* EFI Mode 0 is 80x25 and always present */
        {
                .columns = 80,
                .rows = 25,
                .present = 1,
        },
        /* EFI Mode 1 is always 80x50 */
        {
                .columns = 80,
                .rows = 50,
                .present = 0,
        },
        /* Value are unknown until we query the console */
        {
                .columns = 0,
                .rows = 0,
                .present = 0,
        },
};

const efi_guid_t efi_guid_text_input_ex_protocol =
                        EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL_GUID;
const efi_guid_t efi_guid_text_input_protocol =
                        EFI_SIMPLE_TEXT_INPUT_PROTOCOL_GUID;
const efi_guid_t efi_guid_text_output_protocol =
                        EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL_GUID;

#define cESC '\x1b'
#define ESC "\x1b"

/* Default to mode 0 */
static struct simple_text_output_mode efi_con_mode = {
        .max_mode = 1,
        .mode = 0,
        .attribute = 0,
        .cursor_column = 0,
        .cursor_row = 0,
        .cursor_visible = 1,
};

static int term_get_char(s32 *c)
{
        u64 timeout;

        /* Wait up to 100 ms for a character */
        timeout = timer_get_us() + 100000;

        while (!tstc())
                if (timer_get_us() > timeout)
                        return 1;

        *c = getchar();
        return 0;
}

/**
 * Receive and parse a reply from the terminal.
 *
 * @n:          array of return values
 * @num:        number of return values expected
 * @end_char:   character indicating end of terminal message
 * Return:      non-zero indicates error
 */
static int term_read_reply(int *n, int num, char end_char)
{
        s32 c;
        int i = 0;

        if (term_get_char(&c) || c != cESC)
                return -1;

        if (term_get_char(&c) || c != '[')
                return -1;

        n[0] = 0;
        while (1) {
                if (!term_get_char(&c)) {
                        if (c == ';') {
                                i++;
                                if (i >= num)
                                        return -1;
                                n[i] = 0;
                                continue;
                        } else if (c == end_char) {
                                break;
                        } else if (c > '9' || c < '0') {
                                return -1;
                        }

                        /* Read one more decimal position */
                        n[i] *= 10;
                        n[i] += c - '0';
                } else {
                        return -1;
                }
        }
        if (i != num - 1)
                return -1;

        return 0;
}

/**
 * efi_cout_output_string() - write Unicode string to console
 *
 * This function implements the OutputString service of the simple text output
 * protocol. See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @this:       simple text output protocol
 * @string:     u16 string
 * Return:      status code
 */
static efi_status_t EFIAPI efi_cout_output_string(
                        struct efi_simple_text_output_protocol *this,
                        const u16 *string)
{
        struct simple_text_output_mode *con = &efi_con_mode;
        struct cout_mode *mode = &efi_cout_modes[con->mode];
        char *buf, *pos;
        const u16 *p;
        efi_status_t ret = EFI_SUCCESS;

        EFI_ENTRY("%p, %p", this, string);

        if (!this || !string) {
                ret = EFI_INVALID_PARAMETER;
                goto out;
        }

        buf = malloc(utf16_utf8_strlen(string) + 1);
        if (!buf) {
                ret = EFI_OUT_OF_RESOURCES;
                goto out;
        }
        pos = buf;
        utf16_utf8_strcpy(&pos, string);
        fputs(stdout, buf);
        free(buf);

        /*
         * Update the cursor position.
         *
         * The UEFI spec provides advance rules for U+0000, U+0008, U+000A,
         * and U000D. All other control characters are ignored. Any non-control
         * character increase the column by one.
         */
        for (p = string; *p; ++p) {
                switch (*p) {
                case '\b':      /* U+0008, backspace */
                        if (con->cursor_column)
                                con->cursor_column--;
                        break;
                case '\n':      /* U+000A, newline */
                        con->cursor_column = 0;
                        con->cursor_row++;
                        break;
                case '\r':      /* U+000D, carriage-return */
                        con->cursor_column = 0;
                        break;
                case 0xd800 ... 0xdbff:
                        /*
                         * Ignore high surrogates, we do not want to count a
                         * Unicode character twice.
                         */
                        break;
                default:
                        /* Exclude control codes */
                        if (*p > 0x1f)
                                con->cursor_column++;
                        break;
                }
                if (con->cursor_column >= mode->columns) {
                        con->cursor_column = 0;
                        con->cursor_row++;
                }
                /*
                 * When we exceed the row count the terminal will scroll up one
                 * line. We have to adjust the cursor position.
                 */
                if (con->cursor_row >= mode->rows && con->cursor_row)
                        con->cursor_row--;
        }

out:
        return EFI_EXIT(ret);
}

/**
 * efi_cout_test_string() - test writing Unicode string to console
 *
 * This function implements the TestString service of the simple text output
 * protocol. See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * As in OutputString we simply convert UTF-16 to UTF-8 there are no unsupported
 * code points and we can always return EFI_SUCCESS.
 *
 * @this:       simple text output protocol
 * @string:     u16 string
 * Return:      status code
 */
static efi_status_t EFIAPI efi_cout_test_string(
                        struct efi_simple_text_output_protocol *this,
                        const u16 *string)
{
        EFI_ENTRY("%p, %p", this, string);
        return EFI_EXIT(EFI_SUCCESS);
}

/**
 * cout_mode_matches() - check if mode has given terminal size
 *
 * @mode:       text mode
 * @rows:       number of rows
 * @cols:       number of columns
 * Return:      true if number of rows and columns matches the mode and
 *              the mode is present
 */
static bool cout_mode_matches(struct cout_mode *mode, int rows, int cols)
{
        if (!mode->present)
                return false;

        return (mode->rows == rows) && (mode->columns == cols);
}

/**
 * query_console_serial() - query serial console size
 *
 * When using a serial console or the net console we can only devise the
 * terminal size by querying the terminal using ECMA-48 control sequences.
 *
 * @rows:       pointer to return number of rows
 * @cols:       pointer to return number of columns
 * Returns:     0 on success
 */
static int query_console_serial(int *rows, int *cols)
{
        int ret = 0;
        int n[2];

        /* Empty input buffer */
        while (tstc())
                getchar();

        /*
         * Not all terminals understand CSI [18t for querying the console size.
         * We should adhere to escape sequences documented in the console_codes
         * man page and the ECMA-48 standard.
         *
         * So here we follow a different approach. We position the cursor to the
         * bottom right and query its position. Before leaving the function we
         * restore the original cursor position.
         */
        printf(ESC "7"          /* Save cursor position */
               ESC "[r"         /* Set scrolling region to full window */
               ESC "[999;999H"  /* Move to bottom right corner */
               ESC "[6n");      /* Query cursor position */

        /* Read {rows,cols} */
        if (term_read_reply(n, 2, 'R')) {
                ret = 1;
                goto out;
        }

        *cols = n[1];
        *rows = n[0];
out:
        printf(ESC "8");        /* Restore cursor position */
        return ret;
}

/**
 * query_vidconsole() - query video console size
 *
 *
 * @rows:       pointer to return number of rows
 * @cols:       pointer to return number of columns
 * Returns:     0 on success
 */
static int __maybe_unused query_vidconsole(int *rows, int *cols)
{
        const char *stdout_name = env_get("stdout");
        struct stdio_dev *stdout_dev;
        struct udevice *dev;
        struct vidconsole_priv *priv;

        if (!stdout_name || strncmp(stdout_name, "vidconsole", 10))
                return -ENODEV;
        stdout_dev = stdio_get_by_name("vidconsole");
        if (!stdout_dev)
                return -ENODEV;
        dev = stdout_dev->priv;
        if (!dev)
                return -ENODEV;
        priv = dev_get_uclass_priv(dev);
        if (!priv)
                return -ENODEV;
        *rows = priv->rows;
        *cols = priv->cols;
        return 0;
}

/**
 * query_console_size() - update the mode table.
 *
 * By default the only mode available is 80x25. If the console has at least 50
 * lines, enable mode 80x50. If we can query the console size and it is neither
 * 80x25 nor 80x50, set it as an additional mode.
 */
static void query_console_size(void)
{
        int rows = 25, cols = 80;
        int ret = -ENODEV;

        if IS_ENABLED(CONFIG_DM_VIDEO)
                ret = query_vidconsole(&rows, &cols);
        if (ret)
                ret = query_console_serial(&rows, &cols);
        if (ret)
                return;

        /* Test if we can have Mode 1 */
        if (cols >= 80 && rows >= 50) {
                efi_cout_modes[1].present = 1;
                efi_con_mode.max_mode = 2;
        }

        /*
         * Install our mode as mode 2 if it is different
         * than mode 0 or 1 and set it as the currently selected mode
         */
        if (!cout_mode_matches(&efi_cout_modes[0], rows, cols) &&
            !cout_mode_matches(&efi_cout_modes[1], rows, cols)) {
                efi_cout_modes[EFI_COUT_MODE_2].columns = cols;
                efi_cout_modes[EFI_COUT_MODE_2].rows = rows;
                efi_cout_modes[EFI_COUT_MODE_2].present = 1;
                efi_con_mode.max_mode = EFI_MAX_COUT_MODE;
                efi_con_mode.mode = EFI_COUT_MODE_2;
        }
}


/**
 * efi_cout_query_mode() - get terminal size for a text mode
 *
 * This function implements the QueryMode service of the simple text output
 * protocol. See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @this:               simple text output protocol
 * @mode_number:        mode number to retrieve information on
 * @columns:            number of columns
 * @rows:               number of rows
 * Return:              status code
 */
static efi_status_t EFIAPI efi_cout_query_mode(
                        struct efi_simple_text_output_protocol *this,
                        unsigned long mode_number, unsigned long *columns,
                        unsigned long *rows)
{
        EFI_ENTRY("%p, %ld, %p, %p", this, mode_number, columns, rows);

        if (mode_number >= efi_con_mode.max_mode)
                return EFI_EXIT(EFI_UNSUPPORTED);

        if (efi_cout_modes[mode_number].present != 1)
                return EFI_EXIT(EFI_UNSUPPORTED);

        if (columns)
                *columns = efi_cout_modes[mode_number].columns;
        if (rows)
                *rows = efi_cout_modes[mode_number].rows;

        return EFI_EXIT(EFI_SUCCESS);
}

static const struct {
        unsigned int fg;
        unsigned int bg;
} color[] = {
        { 30, 40 },     /* 0: black */
        { 34, 44 },     /* 1: blue */
        { 32, 42 },     /* 2: green */
        { 36, 46 },     /* 3: cyan */
        { 31, 41 },     /* 4: red */
        { 35, 45 },     /* 5: magenta */
        { 33, 43 },     /* 6: brown, map to yellow as EDK2 does*/
        { 37, 47 },     /* 7: light gray, map to white */
};

/**
 * efi_cout_set_attribute() - set fore- and background color
 *
 * This function implements the SetAttribute service of the simple text output
 * protocol. See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @this:       simple text output protocol
 * @attribute:  foreground color - bits 0-3, background color - bits 4-6
 * Return:      status code
 */
static efi_status_t EFIAPI efi_cout_set_attribute(
                        struct efi_simple_text_output_protocol *this,
                        unsigned long attribute)
{
        unsigned int bold = EFI_ATTR_BOLD(attribute);
        unsigned int fg = EFI_ATTR_FG(attribute);
        unsigned int bg = EFI_ATTR_BG(attribute);

        EFI_ENTRY("%p, %lx", this, attribute);

        efi_con_mode.attribute = attribute;
        if (attribute)
                printf(ESC"[%u;%u;%um", bold, color[fg].fg, color[bg].bg);
        else
                printf(ESC"[0;37;40m");

        return EFI_EXIT(EFI_SUCCESS);
}

/**
 * efi_cout_clear_screen() - clear screen
 *
 * This function implements the ClearScreen service of the simple text output
 * protocol. See the Unified Extensible Firmware Interface (UEFI) specification
 * for details.
 *
 * @this:       pointer to the protocol instance
 * Return:      status code
 */
static efi_status_t EFIAPI efi_cout_clear_screen(
                        struct efi_simple_text_output_protocol *this)
{
        EFI_ENTRY("%p", this);

        /*
         * The Linux console wants both a clear and a home command. The video
         * uclass does not support <ESC>[H without coordinates, yet.
         */
        printf(ESC "[2J" ESC "[1;1H");
        efi_con_mode.cursor_column = 0;
        efi_con_mode.cursor_row = 0;

        return EFI_EXIT(EFI_SUCCESS);
}

/**
 * efi_cout_clear_set_mode() - set text model
 *
 * This function implements the SetMode service of the simple text output
 * protocol. See the Unified Extensible Firmware  Interface (UEFI) specification
 * for details.
 *
 * @this:               pointer to the protocol instance
 * @mode_number:        number of the text mode to set
 * Return:              status code
 */
static efi_status_t EFIAPI efi_cout_set_mode(
                        struct efi_simple_text_output_protocol *this,
                        unsigned long mode_number)
{
        EFI_ENTRY("%p, %ld", this, mode_number);

        if (mode_number >= efi_con_mode.max_mode)
                return EFI_EXIT(EFI_UNSUPPORTED);

        if (!efi_cout_modes[mode_number].present)
                return EFI_EXIT(EFI_UNSUPPORTED);

        efi_con_mode.mode = mode_number;
        EFI_CALL(efi_cout_clear_screen(this));

        return EFI_EXIT(EFI_SUCCESS);
}

/**
 * efi_cout_reset() - reset the terminal
 *
 * This function implements the Reset service of the simple text output
 * protocol. See the Unified Extensible Firmware  Interface (UEFI) specification
 * for details.
 *
 * @this:                       pointer to the protocol instance
 * @extended_verification:      if set an extended verification may be executed
 * Return:                      status code
 */
static efi_status_t EFIAPI efi_cout_reset(
                        struct efi_simple_text_output_protocol *this,
                        char extended_verification)
{
        EFI_ENTRY("%p, %d", this, extended_verification);

        /* Clear screen */
        EFI_CALL(efi_cout_clear_screen(this));
        /* Set default colors */
        efi_con_mode.attribute = 0x07;
        printf(ESC "[0;37;40m");

        return EFI_EXIT(EFI_SUCCESS);
}

/**
 * efi_cout_set_cursor_position() - reset the terminal
 *
 * This function implements the SetCursorPosition service of the simple text
 * output protocol. See the Unified Extensible Firmware  Interface (UEFI)
 * specification for details.
 *
 * @this:       pointer to the protocol instance
 * @column:     column to move to
 * @row:        row to move to
 * Return:      status code
 */
static efi_status_t EFIAPI efi_cout_set_cursor_position(
                        struct efi_simple_text_output_protocol *this,
                        unsigned long column, unsigned long row)
{
        efi_status_t ret = EFI_SUCCESS;
        struct simple_text_output_mode *con = &efi_con_mode;
        struct cout_mode *mode = &efi_cout_modes[con->mode];

        EFI_ENTRY("%p, %ld, %ld", this, column, row);

        /* Check parameters */
        if (!this) {
                ret = EFI_INVALID_PARAMETER;
                goto out;
        }
        if (row >= mode->rows || column >= mode->columns) {
                ret = EFI_UNSUPPORTED;
                goto out;
        }

        /*
         * Set cursor position by sending CSI H.
         * EFI origin is [0, 0], terminal origin is [1, 1].
         */
        printf(ESC "[%d;%dH", (int)row + 1, (int)column + 1);
        efi_con_mode.cursor_column = column;
        efi_con_mode.cursor_row = row;
out:
        return EFI_EXIT(ret);
}

/**
 * efi_cout_enable_cursor() - enable the cursor
 *
 * This function implements the EnableCursor service of the simple text  output
 * protocol. See the Unified Extensible Firmware  Interface (UEFI) specification
 * for details.
 *
 * @this:       pointer to the protocol instance
 * @enable:     if true enable, if false disable the cursor
 * Return:      status code
 */
static efi_status_t EFIAPI efi_cout_enable_cursor(
                        struct efi_simple_text_output_protocol *this,
                        bool enable)
{
        EFI_ENTRY("%p, %d", this, enable);

        printf(ESC"[?25%c", enable ? 'h' : 'l');
        efi_con_mode.cursor_visible = !!enable;

        return EFI_EXIT(EFI_SUCCESS);
}

struct efi_simple_text_output_protocol efi_con_out = {
        .reset = efi_cout_reset,
        .output_string = efi_cout_output_string,
        .test_string = efi_cout_test_string,
        .query_mode = efi_cout_query_mode,
        .set_mode = efi_cout_set_mode,
        .set_attribute = efi_cout_set_attribute,
        .clear_screen = efi_cout_clear_screen,
        .set_cursor_position = efi_cout_set_cursor_position,
        .enable_cursor = efi_cout_enable_cursor,
        .mode = (void*)&efi_con_mode,
};

/**
 * struct efi_cin_notify_function - registered console input notify function
 *
 * @link:       link to list
 * @key:        key to notify
 * @function:   function to call
 */
struct efi_cin_notify_function {
        struct list_head link;
        struct efi_key_data key;
        efi_status_t (EFIAPI *function)
                (struct efi_key_data *key_data);
};

static bool key_available;
static struct efi_key_data next_key;
static LIST_HEAD(cin_notify_functions);

/**
 * set_shift_mask() - set shift mask
 *
 * @mod:        Xterm shift mask
 * @key_state:  receives the state of the shift, alt, control, and logo keys
 */
void set_shift_mask(int mod, struct efi_key_state *key_state)
{
        key_state->key_shift_state = EFI_SHIFT_STATE_VALID;
        if (mod) {
                --mod;
                if (mod & 1)
                        key_state->key_shift_state |= EFI_LEFT_SHIFT_PRESSED;
                if (mod & 2)
                        key_state->key_shift_state |= EFI_LEFT_ALT_PRESSED;
                if (mod & 4)
                        key_state->key_shift_state |= EFI_LEFT_CONTROL_PRESSED;
                if (!mod || (mod & 8))
                        key_state->key_shift_state |= EFI_LEFT_LOGO_PRESSED;
        }
}

/**
 * analyze_modifiers() - analyze modifiers (shift, alt, ctrl) for function keys
 *
 * This gets called when we have already parsed CSI.
 *
 * @key_state:  receives the state of the shift, alt, control, and logo keys
 * Return:      the unmodified code
 */
static int analyze_modifiers(struct efi_key_state *key_state)
{
        int c, mod = 0, ret = 0;

        c = getchar();

        if (c != ';') {
                ret = c;
                if (c == '~')
                        goto out;
                c = getchar();
        }
        for (;;) {
                switch (c) {
                case '0'...'9':
                        mod *= 10;
                        mod += c - '0';
                /* fall through */
                case ';':
                        c = getchar();
                        break;
                default:
                        goto out;
                }
        }
out:
        set_shift_mask(mod, key_state);
        if (!ret)
                ret = c;
        return ret;
}

/**
 * efi_cin_read_key() - read a key from the console input
 *
 * @key:        - key received
 * Return:      - status code
 */
static efi_status_t efi_cin_read_key(struct efi_key_data *key)
{
        struct efi_input_key pressed_key = {
                .scan_code = 0,
                .unicode_char = 0,
        };
        s32 ch;

        if (console_read_unicode(&ch))
                return EFI_NOT_READY;

        key->key_state.key_shift_state = EFI_SHIFT_STATE_INVALID;
        key->key_state.key_toggle_state = EFI_TOGGLE_STATE_INVALID;

        /* We do not support multi-word codes */
        if (ch >= 0x10000)
                ch = '?';

        switch (ch) {
        case 0x1b:
                /*
                 * If a second key is received within 10 ms, assume that we are
                 * dealing with an escape sequence. Otherwise consider this the
                 * escape key being hit. 10 ms is long enough to work fine at
                 * 1200 baud and above.
                 */
                udelay(10000);
                if (!tstc()) {
                        pressed_key.scan_code = 23;
                        break;
                }
                /*
                 * Xterm Control Sequences
                 * https://www.xfree86.org/4.8.0/ctlseqs.html
                 */
                ch = getchar();
                switch (ch) {
                case cESC: /* ESC */
                        pressed_key.scan_code = 23;
                        break;
                case 'O': /* F1 - F4, End */
                        ch = getchar();
                        /* consider modifiers */
                        if (ch == 'F') { /* End */
                                pressed_key.scan_code = 6;
                                break;
                        } else if (ch < 'P') {
                                set_shift_mask(ch - '0', &key->key_state);
                                ch = getchar();
                        }
                        pressed_key.scan_code = ch - 'P' + 11;
                        break;
                case '[':
                        ch = getchar();
                        switch (ch) {
                        case 'A'...'D': /* up, down right, left */
                                pressed_key.scan_code = ch - 'A' + 1;
                                break;
                        case 'F': /* End */
                                pressed_key.scan_code = 6;
                                break;
                        case 'H': /* Home */
                                pressed_key.scan_code = 5;
                                break;
                        case '1':
                                ch = analyze_modifiers(&key->key_state);
                                switch (ch) {
                                case '1'...'5': /* F1 - F5 */
                                        pressed_key.scan_code = ch - '1' + 11;
                                        break;
                                case '6'...'9': /* F5 - F8 */
                                        pressed_key.scan_code = ch - '6' + 15;
                                        break;
                                case 'A'...'D': /* up, down right, left */
                                        pressed_key.scan_code = ch - 'A' + 1;
                                        break;
                                case 'F': /* End */
                                        pressed_key.scan_code = 6;
                                        break;
                                case 'H': /* Home */
                                        pressed_key.scan_code = 5;
                                        break;
                                case '~': /* Home */
                                        pressed_key.scan_code = 5;
                                        break;
                                }
                                break;
                        case '2':
                                ch = analyze_modifiers(&key->key_state);
                                switch (ch) {
                                case '0'...'1': /* F9 - F10 */
                                        pressed_key.scan_code = ch - '0' + 19;
                                        break;
                                case '3'...'4': /* F11 - F12 */
                                        pressed_key.scan_code = ch - '3' + 21;
                                        break;
                                case '~': /* INS */
                                        pressed_key.scan_code = 7;
                                        break;
                                }
                                break;
                        case '3': /* DEL */
                                pressed_key.scan_code = 8;
                                analyze_modifiers(&key->key_state);
                                break;
                        case '5': /* PG UP */
                                pressed_key.scan_code = 9;
                                analyze_modifiers(&key->key_state);
                                break;
                        case '6': /* PG DOWN */
                                pressed_key.scan_code = 10;
                                analyze_modifiers(&key->key_state);
                                break;
                        } /* [ */
                        break;
                default:
                        /* ALT key */
                        set_shift_mask(3, &key->key_state);
                }
                break;
        case 0x7f:
                /* Backspace */
                ch = 0x08;
        }
        if (pressed_key.scan_code) {
                key->key_state.key_shift_state |= EFI_SHIFT_STATE_VALID;
        } else {
                pressed_key.unicode_char = ch;

                /*
                 * Assume left control key for control characters typically
                 * entered using the control key.
                 */
                if (ch >= 0x01 && ch <= 0x1f) {
                        key->key_state.key_shift_state |=
                                        EFI_SHIFT_STATE_VALID;
                        switch (ch) {
                        case 0x01 ... 0x07:
                        case 0x0b ... 0x0c:
                        case 0x0e ... 0x1f:
                                key->key_state.key_shift_state |=
                                                EFI_LEFT_CONTROL_PRESSED;
                        }
                }
        }
        key->key = pressed_key;

        return EFI_SUCCESS;
}

/**
 * efi_cin_notify() - notify registered functions
 */
static void efi_cin_notify(void)
{
        struct efi_cin_notify_function *item;

        list_for_each_entry(item, &cin_notify_functions, link) {
                bool match = true;

                /* We do not support toggle states */
                if (item->key.key.unicode_char || item->key.key.scan_code) {
                        if (item->key.key.unicode_char !=
                            next_key.key.unicode_char ||
                            item->key.key.scan_code != next_key.key.scan_code)
                                match = false;
                }
                if (item->key.key_state.key_shift_state &&
                    item->key.key_state.key_shift_state !=
                    next_key.key_state.key_shift_state)
                        match = false;

                if (match)
                        /* We don't bother about the return code */
                        EFI_CALL(item->function(&next_key));
        }
}

/**
 * efi_cin_check() - check if keyboard input is available
 */
static void efi_cin_check(void)
{
        efi_status_t ret;

        if (key_available) {
                efi_signal_event(efi_con_in.wait_for_key);
                return;
        }

        if (tstc()) {
                ret = efi_cin_read_key(&next_key);
                if (ret == EFI_SUCCESS) {
                        key_available = true;

                        /* Notify registered functions */
                        efi_cin_notify();

                        /* Queue the wait for key event */
                        if (key_available)
                                efi_signal_event(efi_con_in.wait_for_key);
                }
        }
}

/**
 * efi_cin_empty_buffer() - empty input buffer
 */
static void efi_cin_empty_buffer(void)
{
        while (tstc())
                getchar();
        key_available = false;
}

/**
 * efi_cin_reset_ex() - reset console input
 *
 * @this:                       - the extended simple text input protocol
 * @extended_verification:      - extended verification
 *
 * This function implements the reset service of the
 * EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL.
 *
 * See the Unified Extensible Firmware Interface (UEFI) specification for
 * details.
 *
 * Return: old value of the task priority level
 */
static efi_status_t EFIAPI efi_cin_reset_ex(
                struct efi_simple_text_input_ex_protocol *this,
                bool extended_verification)
{
        efi_status_t ret = EFI_SUCCESS;

        EFI_ENTRY("%p, %d", this, extended_verification);

        /* Check parameters */
        if (!this) {
                ret = EFI_INVALID_PARAMETER;
                goto out;
        }

        efi_cin_empty_buffer();
out:
        return EFI_EXIT(ret);
}

/**
 * efi_cin_read_key_stroke_ex() - read key stroke
 *
 * @this:       instance of the EFI_SIMPLE_TEXT_INPUT_PROTOCOL
 * @key_data:   key read from console
 * Return:      status code
 *
 * This function implements the ReadKeyStrokeEx service of the
 * EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL.
 *
 * See the Unified Extensible Firmware Interface (UEFI) specification for
 * details.
 */
static efi_status_t EFIAPI efi_cin_read_key_stroke_ex(
                struct efi_simple_text_input_ex_protocol *this,
                struct efi_key_data *key_data)
{
        efi_status_t ret = EFI_SUCCESS;

        EFI_ENTRY("%p, %p", this, key_data);

        /* Check parameters */
        if (!this || !key_data) {
                ret = EFI_INVALID_PARAMETER;
                goto out;
        }

        /* We don't do interrupts, so check for timers cooperatively */
        efi_timer_check();

        /* Enable console input after ExitBootServices */
        efi_cin_check();

        if (!key_available) {
                ret = EFI_NOT_READY;
                goto out;
        }
        /*
         * CTRL+A - CTRL+Z have to be signaled as a - z.
         * SHIFT+CTRL+A - SHIFT+CTRL+Z have to be signaled as A - Z.
         */
        switch (next_key.key.unicode_char) {
        case 0x01 ... 0x07:
        case 0x0b ... 0x0c:
        case 0x0e ... 0x1a:
                if (!(next_key.key_state.key_toggle_state &
                      EFI_CAPS_LOCK_ACTIVE) ^
                    !(next_key.key_state.key_shift_state &
                      (EFI_LEFT_SHIFT_PRESSED | EFI_RIGHT_SHIFT_PRESSED)))
                        next_key.key.unicode_char += 0x40;
                else
                        next_key.key.unicode_char += 0x60;
        }
        *key_data = next_key;
        key_available = false;
        efi_con_in.wait_for_key->is_signaled = false;

out:
        return EFI_EXIT(ret);
}

/**
 * efi_cin_set_state() - set toggle key state
 *
 * @this:               instance of the EFI_SIMPLE_TEXT_INPUT_PROTOCOL
 * @key_toggle_state:   pointer to key toggle state
 * Return:              status code
 *
 * This function implements the SetState service of the
 * EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL.
 *
 * See the Unified Extensible Firmware Interface (UEFI) specification for
 * details.
 */
static efi_status_t EFIAPI efi_cin_set_state(
                struct efi_simple_text_input_ex_protocol *this,
                u8 *key_toggle_state)
{
        EFI_ENTRY("%p, %p", this, key_toggle_state);
        /*
         * U-Boot supports multiple console input sources like serial and
         * net console for which a key toggle state cannot be set at all.
         *
         * According to the UEFI specification it is allowable to not implement
         * this service.
         */
        return EFI_EXIT(EFI_UNSUPPORTED);
}

/**
 * efi_cin_register_key_notify() - register key notification function
 *
 * @this:                       instance of the EFI_SIMPLE_TEXT_INPUT_PROTOCOL
 * @key_data:                   key to be notified
 * @key_notify_function:        function to be called if the key is pressed
 * @notify_handle:              handle for unregistering the notification
 * Return:                      status code
 *
 * This function implements the SetState service of the
 * EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL.
 *
 * See the Unified Extensible Firmware Interface (UEFI) specification for
 * details.
 */
static efi_status_t EFIAPI efi_cin_register_key_notify(
                struct efi_simple_text_input_ex_protocol *this,
                struct efi_key_data *key_data,
                efi_status_t (EFIAPI *key_notify_function)(
                        struct efi_key_data *key_data),
                void **notify_handle)
{
        efi_status_t ret = EFI_SUCCESS;
        struct efi_cin_notify_function *notify_function;

        EFI_ENTRY("%p, %p, %p, %p",
                  this, key_data, key_notify_function, notify_handle);

        /* Check parameters */
        if (!this || !key_data || !key_notify_function || !notify_handle) {
                ret = EFI_INVALID_PARAMETER;
                goto out;
        }

        EFI_PRINT("u+%04x, sc %04x, sh %08x, tg %02x\n",
                  key_data->key.unicode_char,
               key_data->key.scan_code,
               key_data->key_state.key_shift_state,
               key_data->key_state.key_toggle_state);

        notify_function = calloc(1, sizeof(struct efi_cin_notify_function));
        if (!notify_function) {
                ret = EFI_OUT_OF_RESOURCES;
                goto out;
        }
        notify_function->key = *key_data;
        notify_function->function = key_notify_function;
        list_add_tail(&notify_function->link, &cin_notify_functions);
        *notify_handle = notify_function;
out:
        return EFI_EXIT(ret);
}

/**
 * efi_cin_unregister_key_notify() - unregister key notification function
 *
 * @this:                       instance of the EFI_SIMPLE_TEXT_INPUT_PROTOCOL
 * @notification_handle:        handle received when registering
 * Return:                      status code
 *
 * This function implements the SetState service of the
 * EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL.
 *
 * See the Unified Extensible Firmware Interface (UEFI) specification for
 * details.
 */
static efi_status_t EFIAPI efi_cin_unregister_key_notify(
                struct efi_simple_text_input_ex_protocol *this,
                void *notification_handle)
{
        efi_status_t ret = EFI_INVALID_PARAMETER;
        struct efi_cin_notify_function *item, *notify_function =
                        notification_handle;

        EFI_ENTRY("%p, %p", this, notification_handle);

        /* Check parameters */
        if (!this || !notification_handle)
                goto out;

        list_for_each_entry(item, &cin_notify_functions, link) {
                if (item == notify_function) {
                        ret = EFI_SUCCESS;
                        break;
                }
        }
        if (ret != EFI_SUCCESS)
                goto out;

        /* Remove the notify function */
        list_del(&notify_function->link);
        free(notify_function);
out:
        return EFI_EXIT(ret);
}


/**
 * efi_cin_reset() - drain the input buffer
 *
 * @this:                       instance of the EFI_SIMPLE_TEXT_INPUT_PROTOCOL
 * @extended_verification:      allow for exhaustive verification
 * Return:                      status code
 *
 * This function implements the Reset service of the
 * EFI_SIMPLE_TEXT_INPUT_PROTOCOL.
 *
 * See the Unified Extensible Firmware Interface (UEFI) specification for
 * details.
 */
static efi_status_t EFIAPI efi_cin_reset
                        (struct efi_simple_text_input_protocol *this,
                         bool extended_verification)
{
        efi_status_t ret = EFI_SUCCESS;

        EFI_ENTRY("%p, %d", this, extended_verification);

        /* Check parameters */
        if (!this) {
                ret = EFI_INVALID_PARAMETER;
                goto out;
        }

        efi_cin_empty_buffer();
out:
        return EFI_EXIT(ret);
}

/**
 * efi_cin_read_key_stroke() - read key stroke
 *
 * @this:       instance of the EFI_SIMPLE_TEXT_INPUT_PROTOCOL
 * @key:        key read from console
 * Return:      status code
 *
 * This function implements the ReadKeyStroke service of the
 * EFI_SIMPLE_TEXT_INPUT_PROTOCOL.
 *
 * See the Unified Extensible Firmware Interface (UEFI) specification for
 * details.
 */
static efi_status_t EFIAPI efi_cin_read_key_stroke
                        (struct efi_simple_text_input_protocol *this,
                         struct efi_input_key *key)
{
        efi_status_t ret = EFI_SUCCESS;

        EFI_ENTRY("%p, %p", this, key);

        /* Check parameters */
        if (!this || !key) {
                ret = EFI_INVALID_PARAMETER;
                goto out;
        }

        /* We don't do interrupts, so check for timers cooperatively */
        efi_timer_check();

        /* Enable console input after ExitBootServices */
        efi_cin_check();

        if (!key_available) {
                ret = EFI_NOT_READY;
                goto out;
        }
        *key = next_key.key;
        key_available = false;
        efi_con_in.wait_for_key->is_signaled = false;
out:
        return EFI_EXIT(ret);
}

static struct efi_simple_text_input_ex_protocol efi_con_in_ex = {
        .reset = efi_cin_reset_ex,
        .read_key_stroke_ex = efi_cin_read_key_stroke_ex,
        .wait_for_key_ex = NULL,
        .set_state = efi_cin_set_state,
        .register_key_notify = efi_cin_register_key_notify,
        .unregister_key_notify = efi_cin_unregister_key_notify,
};

struct efi_simple_text_input_protocol efi_con_in = {
        .reset = efi_cin_reset,
        .read_key_stroke = efi_cin_read_key_stroke,
        .wait_for_key = NULL,
};

static struct efi_event *console_timer_event;

/*
 * efi_console_timer_notify() - notify the console timer event
 *
 * @event:      console timer event
 * @context:    not used
 */
static void EFIAPI efi_console_timer_notify(struct efi_event *event,
                                            void *context)
{
        EFI_ENTRY("%p, %p", event, context);
        efi_cin_check();
        EFI_EXIT(EFI_SUCCESS);
}

/**
 * efi_key_notify() - notify the wait for key event
 *
 * @event:      wait for key event
 * @context:    not used
 */
static void EFIAPI efi_key_notify(struct efi_event *event, void *context)
{
        EFI_ENTRY("%p, %p", event, context);
        efi_cin_check();
        EFI_EXIT(EFI_SUCCESS);
}

/**
 * efi_console_register() - install the console protocols
 *
 * This function is called from do_bootefi_exec().
 *
 * Return:      status code
 */
efi_status_t efi_console_register(void)
{
        efi_status_t r;
        efi_handle_t console_output_handle;
        efi_handle_t console_input_handle;

        /* Set up mode information */
        query_console_size();

        /* Create handles */
        r = efi_create_handle(&console_output_handle);
        if (r != EFI_SUCCESS)
                goto out_of_memory;

        r = efi_add_protocol(console_output_handle,
                             &efi_guid_text_output_protocol, &efi_con_out);
        if (r != EFI_SUCCESS)
                goto out_of_memory;
        systab.con_out_handle = console_output_handle;
        systab.stderr_handle = console_output_handle;

        r = efi_create_handle(&console_input_handle);
        if (r != EFI_SUCCESS)
                goto out_of_memory;

        r = efi_add_protocol(console_input_handle,
                             &efi_guid_text_input_protocol, &efi_con_in);
        if (r != EFI_SUCCESS)
                goto out_of_memory;
        systab.con_in_handle = console_input_handle;
        r = efi_add_protocol(console_input_handle,
                             &efi_guid_text_input_ex_protocol, &efi_con_in_ex);
        if (r != EFI_SUCCESS)
                goto out_of_memory;

        /* Create console events */
        r = efi_create_event(EVT_NOTIFY_WAIT, TPL_CALLBACK, efi_key_notify,
                             NULL, NULL, &efi_con_in.wait_for_key);
        if (r != EFI_SUCCESS) {
                printf("ERROR: Failed to register WaitForKey event\n");
                return r;
        }
        efi_con_in_ex.wait_for_key_ex = efi_con_in.wait_for_key;
        r = efi_create_event(EVT_TIMER | EVT_NOTIFY_SIGNAL, TPL_CALLBACK,
                             efi_console_timer_notify, NULL, NULL,
                             &console_timer_event);
        if (r != EFI_SUCCESS) {
                printf("ERROR: Failed to register console event\n");
                return r;
        }
        /* 5000 ns cycle is sufficient for 2 MBaud */
        r = efi_set_timer(console_timer_event, EFI_TIMER_PERIODIC, 50);
        if (r != EFI_SUCCESS)
                printf("ERROR: Failed to set console timer\n");
        return r;
out_of_memory:
        printf("ERROR: Out of memory\n");
        return r;
}