/*
 *  linux/drivers/video/iplan2p4.c -- Low level frame buffer operations for
 *                                    interleaved bitplanes à la Atari (4
 *                                    planes, 2 bytes interleave)
 *
 *      Created 5 Apr 1997 by Geert Uytterhoeven
 *
 *  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/module.h>
#include <linux/string.h>
#include <linux/fb.h>

#include <asm/setup.h>

#include "atafb.h"

#define BPL     4
#include "atafb_utils.h"

void atafb_iplan2p4_copyarea(struct fb_info *info, u_long next_line,
                             int sy, int sx, int dy, int dx,
                             int height, int width)
{
        /*  bmove() has to distinguish two major cases: If both, source and
         *  destination, start at even addresses or both are at odd
         *  addresses, just the first odd and last even column (if present)
         *  require special treatment (memmove_col()). The rest between
         *  then can be copied by normal operations, because all adjacent
         *  bytes are affected and are to be stored in the same order.
         *    The pathological case is when the move should go from an odd
         *  address to an even or vice versa. Since the bytes in the plane
         *  words must be assembled in new order, it seems wisest to make
         *  all movements by memmove_col().
         */

        u8 *src, *dst;
        u32 *s, *d;
        int w, l , i, j;
        u_int colsize;
        u_int upwards = (dy < sy) || (dy == sy && dx < sx);

        colsize = height;
        if (!((sx ^ dx) & 15)) {
                /* odd->odd or even->even */

                if (upwards) {
                        src = (u8 *)info->screen_base + sy * next_line + (sx & ~15) / (8 / BPL);
                        dst = (u8 *)info->screen_base + dy * next_line + (dx & ~15) / (8 / BPL);
                        if (sx & 15) {
                                memmove32_col(dst, src, 0xff00ff, height, next_line - BPL * 2);
                                src += BPL * 2;
                                dst += BPL * 2;
                                width -= 8;
                        }
                        w = width >> 4;
                        if (w) {
                                s = (u32 *)src;
                                d = (u32 *)dst;
                                w *= BPL / 2;
                                l = next_line - w * 4;
                                for (j = height; j > 0; j--) {
                                        for (i = w; i > 0; i--)
                                                *d++ = *s++;
                                        s = (u32 *)((u8 *)s + l);
                                        d = (u32 *)((u8 *)d + l);
                                }
                        }
                        if (width & 15)
                                memmove32_col(dst + width / (8 / BPL), src + width / (8 / BPL),
                                              0xff00ff00, height, next_line - BPL * 2);
                } else {
                        src = (u8 *)info->screen_base + (sy - 1) * next_line + ((sx + width + 8) & ~15) / (8 / BPL);
                        dst = (u8 *)info->screen_base + (dy - 1) * next_line + ((dx + width + 8) & ~15) / (8 / BPL);

                        if ((sx + width) & 15) {
                                src -= BPL * 2;
                                dst -= BPL * 2;
                                memmove32_col(dst, src, 0xff00ff00, colsize, -next_line - BPL * 2);
                                width -= 8;
                        }
                        w = width >> 4;
                        if (w) {
                                s = (u32 *)src;
                                d = (u32 *)dst;
                                w *= BPL / 2;
                                l = next_line - w * 4;
                                for (j = height; j > 0; j--) {
                                        for (i = w; i > 0; i--)
                                                *--d = *--s;
                                        s = (u32 *)((u8 *)s - l);
                                        d = (u32 *)((u8 *)d - l);
                                }
                        }
                        if (sx & 15)
                                memmove32_col(dst - (width - 16) / (8 / BPL),
                                              src - (width - 16) / (8 / BPL),
                                              0xff00ff, colsize, -next_line - BPL * 2);
                }
        } else {
                /* odd->even or even->odd */
                if (upwards) {
                        u32 *src32, *dst32;
                        u32 pval[4], v, v1, mask;
                        int i, j, w, f;

                        src = (u8 *)info->screen_base + sy * next_line + (sx & ~15) / (8 / BPL);
                        dst = (u8 *)info->screen_base + dy * next_line + (dx & ~15) / (8 / BPL);

                        mask = 0xff00ff00;
                        f = 0;
                        w = width;
                        if (sx & 15) {
                                f = 1;
                                w += 8;
                        }
                        if ((sx + width) & 15)
                                f |= 2;
                        w >>= 4;
                        for (i = height; i; i--) {
                                src32 = (u32 *)src;
                                dst32 = (u32 *)dst;

                                if (f & 1) {
                                        pval[0] = (*src32++ << 8) & mask;
                                        pval[1] = (*src32++ << 8) & mask;
                                } else {
                                        pval[0] = dst32[0] & mask;
                                        pval[1] = dst32[1] & mask;
                                }

                                for (j = w; j > 0; j--) {
                                        v = *src32++;
                                        v1 = v & mask;
                                        *dst32++ = pval[0] | (v1 >> 8);
                                        pval[0] = (v ^ v1) << 8;
                                        v = *src32++;
                                        v1 = v & mask;
                                        *dst32++ = pval[1] | (v1 >> 8);
                                        pval[1] = (v ^ v1) << 8;
                                }

                                if (f & 2) {
                                        dst32[0] = (dst32[0] & mask) | pval[0];
                                        dst32[1] = (dst32[1] & mask) | pval[1];
                                }

                                src += next_line;
                                dst += next_line;
                        }
                } else {
                        u32 *src32, *dst32;
                        u32 pval[4], v, v1, mask;
                        int i, j, w, f;

                        src = (u8 *)info->screen_base + (sy - 1) * next_line + ((sx + width + 8) & ~15) / (8 / BPL);
                        dst = (u8 *)info->screen_base + (dy - 1) * next_line + ((dx + width + 8) & ~15) / (8 / BPL);

                        mask = 0xff00ff;
                        f = 0;
                        w = width;
                        if ((dx + width) & 15)
                                f = 1;
                        if (sx & 15) {
                                f |= 2;
                                w += 8;
                        }
                        w >>= 4;
                        for (i = height; i; i--) {
                                src32 = (u32 *)src;
                                dst32 = (u32 *)dst;

                                if (f & 1) {
                                        pval[0] = dst32[-1] & mask;
                                        pval[1] = dst32[-2] & mask;
                                } else {
                                        pval[0] = (*--src32 >> 8) & mask;
                                        pval[1] = (*--src32 >> 8) & mask;
                                }

                                for (j = w; j > 0; j--) {
                                        v = *--src32;
                                        v1 = v & mask;
                                        *--dst32 = pval[0] | (v1 << 8);
                                        pval[0] = (v ^ v1) >> 8;
                                        v = *--src32;
                                        v1 = v & mask;
                                        *--dst32 = pval[1] | (v1 << 8);
                                        pval[1] = (v ^ v1) >> 8;
                                }

                                if (!(f & 2)) {
                                        dst32[-1] = (dst32[-1] & mask) | pval[0];
                                        dst32[-2] = (dst32[-2] & mask) | pval[1];
                                }

                                src -= next_line;
                                dst -= next_line;
                        }
                }
        }
}

void atafb_iplan2p4_fillrect(struct fb_info *info, u_long next_line, u32 color,
                             int sy, int sx, int height, int width)
{
        u32 *dest;
        int rows, i;
        u32 cval[4];

        dest = (u32 *)(info->screen_base + sy * next_line + (sx & ~15) / (8 / BPL));
        if (sx & 15) {
                u8 *dest8 = (u8 *)dest + 1;

                expand8_col2mask(color, cval);

                for (i = height; i; i--) {
                        fill8_col(dest8, cval);
                        dest8 += next_line;
                }
                dest += BPL / 2;
                width -= 8;
        }

        expand16_col2mask(color, cval);
        rows = width >> 4;
        if (rows) {
                u32 *d = dest;
                u32 off = next_line - rows * BPL * 2;
                for (i = height; i; i--) {
                        d = fill16_col(d, rows, cval);
                        d = (u32 *)((long)d + off);
                }
                dest += rows * BPL / 2;
                width &= 15;
        }

        if (width) {
                u8 *dest8 = (u8 *)dest;

                expand8_col2mask(color, cval);

                for (i = height; i; i--) {
                        fill8_col(dest8, cval);
                        dest8 += next_line;
                }
        }
}

void atafb_iplan2p4_linefill(struct fb_info *info, u_long next_line,
                             int dy, int dx, u32 width,
                             const u8 *data, u32 bgcolor, u32 fgcolor)
{
        u32 *dest;
        const u16 *data16;
        int rows;
        u32 fgm[4], bgm[4], m;

        dest = (u32 *)(info->screen_base + dy * next_line + (dx & ~15) / (8 / BPL));
        if (dx & 15) {
                fill8_2col((u8 *)dest + 1, fgcolor, bgcolor, *data++);
                dest += BPL / 2;
                width -= 8;
        }

        if (width >= 16) {
                data16 = (const u16 *)data;
                expand16_2col2mask(fgcolor, bgcolor, fgm, bgm);

                for (rows = width / 16; rows; rows--) {
                        u16 d = *data16++;
                        m = d | ((u32)d << 16);
                        *dest++ = (m & fgm[0]) ^ bgm[0];
                        *dest++ = (m & fgm[1]) ^ bgm[1];
                }

                data = (const u8 *)data16;
                width &= 15;
        }

        if (width)
                fill8_2col((u8 *)dest, fgcolor, bgcolor, *data);
}

#ifdef MODULE
MODULE_LICENSE("GPL");

int init_module(void)
{
        return 0;
}

void cleanup_module(void)
{
}
#endif /* MODULE */


    /*
     *  Visible symbols for modules
     */

EXPORT_SYMBOL(atafb_iplan2p4_copyarea);
EXPORT_SYMBOL(atafb_iplan2p4_fillrect);
EXPORT_SYMBOL(atafb_iplan2p4_linefill);