/*
 *  linux/drivers/video/console/sticon.c - console driver using HP's STI firmware
 *
 *      Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>
 *      Copyright (C) 2002-2020 Helge Deller <deller@gmx.de>
 *
 *  Based on linux/drivers/video/vgacon.c and linux/drivers/video/fbcon.c,
 *  which were
 *
 *      Created 28 Sep 1997 by Geert Uytterhoeven
 *      Rewritten by Martin Mares <mj@ucw.cz>, July 1998
 *      Copyright (C) 1991, 1992  Linus Torvalds
 *                          1995  Jay Estabrook
 *      Copyright (C) 1995 Geert Uytterhoeven
 *      Copyright (C) 1993 Bjoern Brauel
 *                         Roman Hodek
 *      Copyright (C) 1993 Hamish Macdonald
 *                         Greg Harp
 *      Copyright (C) 1994 David Carter [carter@compsci.bristol.ac.uk]
 *
 *            with work by William Rucklidge (wjr@cs.cornell.edu)
 *                         Geert Uytterhoeven
 *                         Jes Sorensen (jds@kom.auc.dk)
 *                         Martin Apel
 *            with work by Guenther Kelleter
 *                         Martin Schaller
 *                         Andreas Schwab
 *                         Emmanuel Marty (core@ggi-project.org)
 *                         Jakub Jelinek (jj@ultra.linux.cz)
 *                         Martin Mares <mj@ucw.cz>
 *
 *  This file is subject to the terms and conditions of the GNU General Public
 *  License.  See the file COPYING in the main directory of this archive for
 *  more details.
 *
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/console.h>
#include <linux/errno.h>
#include <linux/vt_kern.h>
#include <linux/kd.h>
#include <linux/selection.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/font.h>
#include <linux/crc32.h>
#include <linux/fb.h>

#include <asm/io.h>

#include <video/sticore.h>

/* switching to graphics mode */
#define BLANK 0
static int vga_is_gfx;

#define STI_DEF_FONT    sticon_sti->font

/* borrowed from fbcon.c */
#define FNTREFCOUNT(fd) (fd->refcount)
#define FNTCRC(fd)      (fd->crc)
static struct sti_cooked_font *font_data[MAX_NR_CONSOLES];

/* this is the sti_struct used for this console */
static struct sti_struct *sticon_sti;

static const char *sticon_startup(void)
{
    return "STI console";
}

static void sticon_putcs(struct vc_data *conp, const u16 *s, unsigned int count,
                         unsigned int ypos, unsigned int xpos)
{
    if (vga_is_gfx || console_blanked)
            return;

    if (conp->vc_mode != KD_TEXT)
            return;

    while (count--) {
        sti_putc(sticon_sti, scr_readw(s++), ypos, xpos++,
                 font_data[conp->vc_num]);
    }
}

static void sticon_cursor(struct vc_data *conp, bool enable)
{
    unsigned short car1;

    /* no cursor update if screen is blanked */
    if (vga_is_gfx || console_blanked)
        return;

    car1 = conp->vc_screenbuf[conp->state.x + conp->state.y * conp->vc_cols];
    if (!enable) {
        sti_putc(sticon_sti, car1, conp->state.y, conp->state.x,
                 font_data[conp->vc_num]);
        return;
    }

    switch (CUR_SIZE(conp->vc_cursor_type)) {
    case CUR_UNDERLINE:
    case CUR_LOWER_THIRD:
    case CUR_LOWER_HALF:
    case CUR_TWO_THIRDS:
    case CUR_BLOCK:
        sti_putc(sticon_sti, (car1 & 255) + (0 << 8) + (7 << 11),
                 conp->state.y, conp->state.x, font_data[conp->vc_num]);
        break;
    }
}

static bool sticon_scroll(struct vc_data *conp, unsigned int t,
                unsigned int b, enum con_scroll dir, unsigned int count)
{
    struct sti_struct *sti = sticon_sti;

    if (vga_is_gfx)
        return false;

    sticon_cursor(conp, false);

    switch (dir) {
    case SM_UP:
        sti_bmove(sti, t + count, 0, t, 0, b - t - count, conp->vc_cols,
                  font_data[conp->vc_num]);
        sti_clear(sti, b - count, 0, count, conp->vc_cols,
                  conp->vc_video_erase_char, font_data[conp->vc_num]);
        break;

    case SM_DOWN:
        sti_bmove(sti, t, 0, t + count, 0, b - t - count, conp->vc_cols,
                  font_data[conp->vc_num]);
        sti_clear(sti, t, 0, count, conp->vc_cols,
                  conp->vc_video_erase_char, font_data[conp->vc_num]);
        break;
    }

    return false;
}

static void sticon_set_def_font(int unit)
{
        if (font_data[unit] != STI_DEF_FONT) {
                if (--FNTREFCOUNT(font_data[unit]) == 0) {
                        kfree(font_data[unit]->raw_ptr);
                        kfree(font_data[unit]);
                }
                font_data[unit] = STI_DEF_FONT;
        }
}

static int sticon_set_font(struct vc_data *vc, const struct console_font *op,
                           unsigned int vpitch)
{
        struct sti_struct *sti = sticon_sti;
        int vc_cols, vc_rows, vc_old_cols, vc_old_rows;
        int unit = vc->vc_num;
        int w = op->width;
        int h = op->height;
        int size, i, bpc, pitch;
        struct sti_rom_font *new_font;
        struct sti_cooked_font *cooked_font;
        unsigned char *data = op->data, *p;

        if ((w < 6) || (h < 6) || (w > 32) || (h > 32) || (vpitch != 32)
            || (op->charcount != 256 && op->charcount != 512))
                return -EINVAL;
        pitch = ALIGN(w, 8) / 8;
        bpc = pitch * h;
        size = bpc * op->charcount;

        new_font = kmalloc(sizeof(*new_font) + size, STI_LOWMEM);
        if (!new_font)
                return -ENOMEM;

        new_font->first_char = 0;
        new_font->last_char = op->charcount - 1;
        new_font->width = w;
        new_font->height = h;
        new_font->font_type = STI_FONT_HPROMAN8;
        new_font->bytes_per_char = bpc;
        new_font->underline_height = 0;
        new_font->underline_pos = 0;

        cooked_font = kzalloc_obj(*cooked_font);
        if (!cooked_font) {
                kfree(new_font);
                return -ENOMEM;
        }
        cooked_font->raw = new_font;
        cooked_font->raw_ptr = new_font;
        cooked_font->width = w;
        cooked_font->height = h;
        FNTREFCOUNT(cooked_font) = 0;   /* usage counter */

        p = (unsigned char *) new_font;
        p += sizeof(*new_font);
        for (i = 0; i < op->charcount; i++) {
                memcpy(p, data, bpc);
                data += pitch*32;
                p += bpc;
        }
        FNTCRC(cooked_font) = crc32(0, new_font, size + sizeof(*new_font));
        sti_font_convert_bytemode(sti, cooked_font);
        new_font = cooked_font->raw_ptr;

        /* check if font is already used by other console */
        for (i = 0; i < MAX_NR_CONSOLES; i++) {
                if (font_data[i] != STI_DEF_FONT
                    && (FNTCRC(font_data[i]) == FNTCRC(cooked_font))) {
                        kfree(new_font);
                        kfree(cooked_font);
                        /* current font is the same as the new one */
                        if (i == unit)
                                return 0;
                        cooked_font = font_data[i];
                        new_font = cooked_font->raw_ptr;
                        break;
                }
        }

        /* clear screen with old font: we now may have less rows */
        vc_old_rows = vc->vc_rows;
        vc_old_cols = vc->vc_cols;
        sti_clear(sticon_sti, 0, 0, vc_old_rows, vc_old_cols,
                  vc->vc_video_erase_char, font_data[vc->vc_num]);

        /* delete old font in case it is a user font */
        sticon_set_def_font(unit);

        FNTREFCOUNT(cooked_font)++;
        font_data[unit] = cooked_font;

        vc_cols = sti_onscreen_x(sti) / cooked_font->width;
        vc_rows = sti_onscreen_y(sti) / cooked_font->height;
        vc_resize(vc, vc_cols, vc_rows);

        /* need to repaint screen if cols & rows are same as old font */
        if (vc_cols == vc_old_cols && vc_rows == vc_old_rows)
                update_screen(vc);

        return 0;
}

static int sticon_font_default(struct vc_data *vc, struct console_font *op,
                               const char *name)
{
        sticon_set_def_font(vc->vc_num);

        return 0;
}

static int sticon_font_set(struct vc_data *vc, const struct console_font *font,
                           unsigned int vpitch, unsigned int flags)
{
        return sticon_set_font(vc, font, vpitch);
}

static void sticon_init(struct vc_data *c, bool init)
{
    struct sti_struct *sti = sticon_sti;
    int vc_cols, vc_rows;

    sti_set(sti, 0, 0, sti_onscreen_y(sti), sti_onscreen_x(sti), 0);
    vc_cols = sti_onscreen_x(sti) / sti->font->width;
    vc_rows = sti_onscreen_y(sti) / sti->font->height;
    c->vc_can_do_color = 1;

    if (init) {
        c->vc_cols = vc_cols;
        c->vc_rows = vc_rows;
    } else {
        vc_resize(c, vc_cols, vc_rows);
    }
}

static void sticon_deinit(struct vc_data *c)
{
    int i;

    /* free memory used by user font */
    for (i = 0; i < MAX_NR_CONSOLES; i++)
        sticon_set_def_font(i);
}

static void sticon_clear(struct vc_data *conp, unsigned int sy, unsigned int sx,
                         unsigned int width)
{
    sti_clear(sticon_sti, sy, sx, 1, width,
              conp->vc_video_erase_char, font_data[conp->vc_num]);
}

static bool sticon_switch(struct vc_data *conp)
{
    return true;        /* needs refreshing */
}

static bool sticon_blank(struct vc_data *c, enum vesa_blank_mode blank,
                         bool mode_switch)
{
    if (blank == VESA_NO_BLANKING) {
        if (mode_switch)
            vga_is_gfx = 0;
        return true;
    }
    sti_clear(sticon_sti, 0, 0, c->vc_rows, c->vc_cols, BLANK,
              font_data[c->vc_num]);
    if (mode_switch)
        vga_is_gfx = 1;

    return true;
}

static u8 sticon_build_attr(struct vc_data *conp, u8 color,
                            enum vc_intensity intens,
                            bool blink, bool underline, bool reverse,
                            bool italic)
{
        u8 fg = color & 7;
        u8 bg = (color & 0x70) >> 4;

        if (reverse)
                return (fg << 3) | bg;
        else
                return (bg << 3) | fg;
}

static void sticon_invert_region(struct vc_data *conp, u16 *p, int count)
{
    int col = 1; /* vga_can_do_color; */

    while (count--) {
        u16 a = scr_readw(p);

        if (col)
                a = ((a) & 0x88ff) | (((a) & 0x7000) >> 4) | (((a) & 0x0700) << 4);
        else
                a = ((a & 0x0700) == 0x0100) ? 0x7000 : 0x7700;

        scr_writew(a, p++);
    }
}

static const struct consw sti_con = {
        .owner                  = THIS_MODULE,
        .con_startup            = sticon_startup,
        .con_init               = sticon_init,
        .con_deinit             = sticon_deinit,
        .con_clear              = sticon_clear,
        .con_putcs              = sticon_putcs,
        .con_cursor             = sticon_cursor,
        .con_scroll             = sticon_scroll,
        .con_switch             = sticon_switch,
        .con_blank              = sticon_blank,
        .con_font_set           = sticon_font_set,
        .con_font_default       = sticon_font_default,
        .con_build_attr         = sticon_build_attr,
        .con_invert_region      = sticon_invert_region,
};



static int __init sticonsole_init(void)
{
    int err, i;

    /* already initialized ? */
    if (sticon_sti)
         return 0;

    sticon_sti = sti_get_rom(0);
    if (!sticon_sti)
        return -ENODEV;

    for (i = 0; i < MAX_NR_CONSOLES; i++)
        font_data[i] = STI_DEF_FONT;

    pr_info("sticon: Initializing STI text console on %s at [%s]\n",
        sticon_sti->sti_data->inq_outptr.dev_name,
        sticon_sti->pa_path);
    console_lock();
    err = do_take_over_console(&sti_con, 0, MAX_NR_CONSOLES - 1,
                PAGE0->mem_cons.cl_class != CL_DUPLEX);
    console_unlock();

    return err;
}

module_init(sticonsole_init);
MODULE_DESCRIPTION("HP STI console driver");
MODULE_LICENSE("GPL");