/*
 * Copyright 2012 Red Hat Inc.
 * Parts based on xf86-video-ast
 * Copyright (c) 2005 ASPEED Technology Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 * USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 */
/*
 * Authors: Dave Airlie <airlied@redhat.com>
 */
#include <linux/export.h>
#include <drm/drmP.h>
#include <drm/drm_crtc.h>
#include <drm/drm_crtc_helper.h>
#include "ast_drv.h"

#include "ast_tables.h"

static struct ast_i2c_chan *ast_i2c_create(struct drm_device *dev);
static void ast_i2c_destroy(struct ast_i2c_chan *i2c);
static int ast_cursor_set(struct drm_crtc *crtc,
                          struct drm_file *file_priv,
                          uint32_t handle,
                          uint32_t width,
                          uint32_t height);
static int ast_cursor_move(struct drm_crtc *crtc,
                           int x, int y);

static inline void ast_load_palette_index(struct ast_private *ast,
                                     u8 index, u8 red, u8 green,
                                     u8 blue)
{
        ast_io_write8(ast, AST_IO_DAC_INDEX_WRITE, index);
        ast_io_read8(ast, AST_IO_SEQ_PORT);
        ast_io_write8(ast, AST_IO_DAC_DATA, red);
        ast_io_read8(ast, AST_IO_SEQ_PORT);
        ast_io_write8(ast, AST_IO_DAC_DATA, green);
        ast_io_read8(ast, AST_IO_SEQ_PORT);
        ast_io_write8(ast, AST_IO_DAC_DATA, blue);
        ast_io_read8(ast, AST_IO_SEQ_PORT);
}

static void ast_crtc_load_lut(struct drm_crtc *crtc)
{
        struct ast_private *ast = crtc->dev->dev_private;
        struct ast_crtc *ast_crtc = to_ast_crtc(crtc);
        int i;

        if (!crtc->enabled)
                return;

        for (i = 0; i < 256; i++)
                ast_load_palette_index(ast, i, ast_crtc->lut_r[i],
                                       ast_crtc->lut_g[i], ast_crtc->lut_b[i]);
}

static bool ast_get_vbios_mode_info(struct drm_crtc *crtc, struct drm_display_mode *mode,
                                    struct drm_display_mode *adjusted_mode,
                                    struct ast_vbios_mode_info *vbios_mode)
{
        struct ast_private *ast = crtc->dev->dev_private;
        u32 refresh_rate_index = 0, mode_id, color_index, refresh_rate;
        u32 hborder, vborder;

        switch (crtc->fb->bits_per_pixel) {
        case 8:
                vbios_mode->std_table = &vbios_stdtable[VGAModeIndex];
                color_index = VGAModeIndex - 1;
                break;
        case 16:
                vbios_mode->std_table = &vbios_stdtable[HiCModeIndex];
                color_index = HiCModeIndex;
                break;
        case 24:
        case 32:
                vbios_mode->std_table = &vbios_stdtable[TrueCModeIndex];
                color_index = TrueCModeIndex;
                break;
        default:
                return false;
        }

        switch (crtc->mode.crtc_hdisplay) {
        case 640:
                vbios_mode->enh_table = &res_640x480[refresh_rate_index];
                break;
        case 800:
                vbios_mode->enh_table = &res_800x600[refresh_rate_index];
                break;
        case 1024:
                vbios_mode->enh_table = &res_1024x768[refresh_rate_index];
                break;
        case 1280:
                if (crtc->mode.crtc_vdisplay == 800)
                        vbios_mode->enh_table = &res_1280x800[refresh_rate_index];
                else
                        vbios_mode->enh_table = &res_1280x1024[refresh_rate_index];
                break;
        case 1440:
                vbios_mode->enh_table = &res_1440x900[refresh_rate_index];
                break;
        case 1600:
                vbios_mode->enh_table = &res_1600x1200[refresh_rate_index];
                break;
        case 1680:
                vbios_mode->enh_table = &res_1680x1050[refresh_rate_index];
                break;
        case 1920:
                if (crtc->mode.crtc_vdisplay == 1080)
                        vbios_mode->enh_table = &res_1920x1080[refresh_rate_index];
                else
                        vbios_mode->enh_table = &res_1920x1200[refresh_rate_index];
                break;
        default:
                return false;
        }

        refresh_rate = drm_mode_vrefresh(mode);
        while (vbios_mode->enh_table->refresh_rate < refresh_rate) {
                vbios_mode->enh_table++;
                if ((vbios_mode->enh_table->refresh_rate > refresh_rate) ||
                    (vbios_mode->enh_table->refresh_rate == 0xff)) {
                        vbios_mode->enh_table--;
                        break;
                }
        }

        hborder = (vbios_mode->enh_table->flags & HBorder) ? 8 : 0;
        vborder = (vbios_mode->enh_table->flags & VBorder) ? 8 : 0;

        adjusted_mode->crtc_htotal = vbios_mode->enh_table->ht;
        adjusted_mode->crtc_hblank_start = vbios_mode->enh_table->hde + hborder;
        adjusted_mode->crtc_hblank_end = vbios_mode->enh_table->ht - hborder;
        adjusted_mode->crtc_hsync_start = vbios_mode->enh_table->hde + hborder +
                vbios_mode->enh_table->hfp;
        adjusted_mode->crtc_hsync_end = (vbios_mode->enh_table->hde + hborder +
                                         vbios_mode->enh_table->hfp +
                                         vbios_mode->enh_table->hsync);

        adjusted_mode->crtc_vtotal = vbios_mode->enh_table->vt;
        adjusted_mode->crtc_vblank_start = vbios_mode->enh_table->vde + vborder;
        adjusted_mode->crtc_vblank_end = vbios_mode->enh_table->vt - vborder;
        adjusted_mode->crtc_vsync_start = vbios_mode->enh_table->vde + vborder +
                vbios_mode->enh_table->vfp;
        adjusted_mode->crtc_vsync_end = (vbios_mode->enh_table->vde + vborder +
                                         vbios_mode->enh_table->vfp +
                                         vbios_mode->enh_table->vsync);

        refresh_rate_index = vbios_mode->enh_table->refresh_rate_index;
        mode_id = vbios_mode->enh_table->mode_id;

        if (ast->chip == AST1180) {
                /* TODO 1180 */
        } else {
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0x8c, (u8)((color_index & 0xf) << 4));
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0x8d, refresh_rate_index & 0xff);
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0x8e, mode_id & 0xff);

                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0x91, 0xa8);
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0x92, crtc->fb->bits_per_pixel);
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0x93, adjusted_mode->clock / 1000);
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0x94, adjusted_mode->crtc_hdisplay);
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0x95, adjusted_mode->crtc_hdisplay >> 8);

                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0x96, adjusted_mode->crtc_vdisplay);
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0x97, adjusted_mode->crtc_vdisplay >> 8);
        }

        return true;


}
static void ast_set_std_reg(struct drm_crtc *crtc, struct drm_display_mode *mode,
                            struct ast_vbios_mode_info *vbios_mode)
{
        struct ast_private *ast = crtc->dev->dev_private;
        struct ast_vbios_stdtable *stdtable;
        u32 i;
        u8 jreg;

        stdtable = vbios_mode->std_table;

        jreg = stdtable->misc;
        ast_io_write8(ast, AST_IO_MISC_PORT_WRITE, jreg);

        /* Set SEQ */
        ast_set_index_reg(ast, AST_IO_SEQ_PORT, 0x00, 0x03);
        for (i = 0; i < 4; i++) {
                jreg = stdtable->seq[i];
                if (!i)
                        jreg |= 0x20;
                ast_set_index_reg(ast, AST_IO_SEQ_PORT, (i + 1) , jreg);
        }

        /* Set CRTC */
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x11, 0x7f, 0x00);
        for (i = 0; i < 25; i++)
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, i, stdtable->crtc[i]);

        /* set AR */
        jreg = ast_io_read8(ast, AST_IO_INPUT_STATUS1_READ);
        for (i = 0; i < 20; i++) {
                jreg = stdtable->ar[i];
                ast_io_write8(ast, AST_IO_AR_PORT_WRITE, (u8)i);
                ast_io_write8(ast, AST_IO_AR_PORT_WRITE, jreg);
        }
        ast_io_write8(ast, AST_IO_AR_PORT_WRITE, 0x14);
        ast_io_write8(ast, AST_IO_AR_PORT_WRITE, 0x00);

        jreg = ast_io_read8(ast, AST_IO_INPUT_STATUS1_READ);
        ast_io_write8(ast, AST_IO_AR_PORT_WRITE, 0x20);

        /* Set GR */
        for (i = 0; i < 9; i++)
                ast_set_index_reg(ast, AST_IO_GR_PORT, i, stdtable->gr[i]);
}

static void ast_set_crtc_reg(struct drm_crtc *crtc, struct drm_display_mode *mode,
                             struct ast_vbios_mode_info *vbios_mode)
{
        struct ast_private *ast = crtc->dev->dev_private;
        u8 jreg05 = 0, jreg07 = 0, jreg09 = 0, jregAC = 0, jregAD = 0, jregAE = 0;
        u16 temp;

        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x11, 0x7f, 0x00);

        temp = (mode->crtc_htotal >> 3) - 5;
        if (temp & 0x100)
                jregAC |= 0x01; /* HT D[8] */
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x00, 0x00, temp);

        temp = (mode->crtc_hdisplay >> 3) - 1;
        if (temp & 0x100)
                jregAC |= 0x04; /* HDE D[8] */
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x01, 0x00, temp);

        temp = (mode->crtc_hblank_start >> 3) - 1;
        if (temp & 0x100)
                jregAC |= 0x10; /* HBS D[8] */
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x02, 0x00, temp);

        temp = ((mode->crtc_hblank_end >> 3) - 1) & 0x7f;
        if (temp & 0x20)
                jreg05 |= 0x80;  /* HBE D[5] */
        if (temp & 0x40)
                jregAD |= 0x01;  /* HBE D[5] */
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x03, 0xE0, (temp & 0x1f));

        temp = (mode->crtc_hsync_start >> 3) - 1;
        if (temp & 0x100)
                jregAC |= 0x40; /* HRS D[5] */
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x04, 0x00, temp);

        temp = ((mode->crtc_hsync_end >> 3) - 1) & 0x3f;
        if (temp & 0x20)
                jregAD |= 0x04; /* HRE D[5] */
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x05, 0x60, (u8)((temp & 0x1f) | jreg05));

        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xAC, 0x00, jregAC);
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xAD, 0x00, jregAD);

        /* vert timings */
        temp = (mode->crtc_vtotal) - 2;
        if (temp & 0x100)
                jreg07 |= 0x01;
        if (temp & 0x200)
                jreg07 |= 0x20;
        if (temp & 0x400)
                jregAE |= 0x01;
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x06, 0x00, temp);

        temp = (mode->crtc_vsync_start) - 1;
        if (temp & 0x100)
                jreg07 |= 0x04;
        if (temp & 0x200)
                jreg07 |= 0x80;
        if (temp & 0x400)
                jregAE |= 0x08;
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x10, 0x00, temp);

        temp = (mode->crtc_vsync_end - 1) & 0x3f;
        if (temp & 0x10)
                jregAE |= 0x20;
        if (temp & 0x20)
                jregAE |= 0x40;
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x11, 0x70, temp & 0xf);

        temp = mode->crtc_vdisplay - 1;
        if (temp & 0x100)
                jreg07 |= 0x02;
        if (temp & 0x200)
                jreg07 |= 0x40;
        if (temp & 0x400)
                jregAE |= 0x02;
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x12, 0x00, temp);

        temp = mode->crtc_vblank_start - 1;
        if (temp & 0x100)
                jreg07 |= 0x08;
        if (temp & 0x200)
                jreg09 |= 0x20;
        if (temp & 0x400)
                jregAE |= 0x04;
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x15, 0x00, temp);

        temp = mode->crtc_vblank_end - 1;
        if (temp & 0x100)
                jregAE |= 0x10;
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x16, 0x00, temp);

        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x07, 0x00, jreg07);
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x09, 0xdf, jreg09);
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xAE, 0x00, (jregAE | 0x80));

        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x11, 0x7f, 0x80);
}

static void ast_set_offset_reg(struct drm_crtc *crtc)
{
        struct ast_private *ast = crtc->dev->dev_private;

        u16 offset;

        offset = crtc->fb->pitches[0] >> 3;
        ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0x13, (offset & 0xff));
        ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xb0, (offset >> 8) & 0x3f);
}

static void ast_set_dclk_reg(struct drm_device *dev, struct drm_display_mode *mode,
                             struct ast_vbios_mode_info *vbios_mode)
{
        struct ast_private *ast = dev->dev_private;
        struct ast_vbios_dclk_info *clk_info;

        clk_info = &dclk_table[vbios_mode->enh_table->dclk_index];

        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xc0, 0x00, clk_info->param1);
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xc1, 0x00, clk_info->param2);
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xbb, 0x0f,
                               (clk_info->param3 & 0x80) | ((clk_info->param3 & 0x3) << 4));
}

static void ast_set_ext_reg(struct drm_crtc *crtc, struct drm_display_mode *mode,
                             struct ast_vbios_mode_info *vbios_mode)
{
        struct ast_private *ast = crtc->dev->dev_private;
        u8 jregA0 = 0, jregA3 = 0, jregA8 = 0;

        switch (crtc->fb->bits_per_pixel) {
        case 8:
                jregA0 = 0x70;
                jregA3 = 0x01;
                jregA8 = 0x00;
                break;
        case 15:
        case 16:
                jregA0 = 0x70;
                jregA3 = 0x04;
                jregA8 = 0x02;
                break;
        case 32:
                jregA0 = 0x70;
                jregA3 = 0x08;
                jregA8 = 0x02;
                break;
        }

        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xa0, 0x8f, jregA0);
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xa3, 0xf0, jregA3);
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xa8, 0xfd, jregA8);

        /* Set Threshold */
        if (ast->chip == AST2300) {
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xa7, 0x78);
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xa6, 0x60);
        } else if (ast->chip == AST2100 ||
                   ast->chip == AST1100 ||
                   ast->chip == AST2200 ||
                   ast->chip == AST2150) {
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xa7, 0x3f);
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xa6, 0x2f);
        } else {
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xa7, 0x2f);
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xa6, 0x1f);
        }
}

void ast_set_sync_reg(struct drm_device *dev, struct drm_display_mode *mode,
                      struct ast_vbios_mode_info *vbios_mode)
{
        struct ast_private *ast = dev->dev_private;
        u8 jreg;

        jreg = ast_io_read8(ast, AST_IO_MISC_PORT_READ);
        jreg |= (vbios_mode->enh_table->flags & SyncNN);
        ast_io_write8(ast, AST_IO_MISC_PORT_WRITE, jreg);
}

bool ast_set_dac_reg(struct drm_crtc *crtc, struct drm_display_mode *mode,
                     struct ast_vbios_mode_info *vbios_mode)
{
        switch (crtc->fb->bits_per_pixel) {
        case 8:
                break;
        default:
                return false;
        }
        return true;
}

void ast_set_start_address_crt1(struct drm_crtc *crtc, unsigned offset)
{
        struct ast_private *ast = crtc->dev->dev_private;
        u32 addr;

        addr = offset >> 2;
        ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0x0d, (u8)(addr & 0xff));
        ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0x0c, (u8)((addr >> 8) & 0xff));
        ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xaf, (u8)((addr >> 16) & 0xff));

}

static void ast_crtc_dpms(struct drm_crtc *crtc, int mode)
{
        struct ast_private *ast = crtc->dev->dev_private;

        if (ast->chip == AST1180)
                return;

        switch (mode) {
        case DRM_MODE_DPMS_ON:
        case DRM_MODE_DPMS_STANDBY:
        case DRM_MODE_DPMS_SUSPEND:
                ast_set_index_reg_mask(ast, AST_IO_SEQ_PORT, 0x1, 0xdf, 0);
                ast_crtc_load_lut(crtc);
                break;
        case DRM_MODE_DPMS_OFF:
                ast_set_index_reg_mask(ast, AST_IO_SEQ_PORT, 0x1, 0xdf, 0x20);
                break;
        }
}

static bool ast_crtc_mode_fixup(struct drm_crtc *crtc,
                                const struct drm_display_mode *mode,
                                struct drm_display_mode *adjusted_mode)
{
        return true;
}

/* ast is different - we will force move buffers out of VRAM */
static int ast_crtc_do_set_base(struct drm_crtc *crtc,
                                struct drm_framebuffer *fb,
                                int x, int y, int atomic)
{
        struct ast_private *ast = crtc->dev->dev_private;
        struct drm_gem_object *obj;
        struct ast_framebuffer *ast_fb;
        struct ast_bo *bo;
        int ret;
        u64 gpu_addr;

        /* push the previous fb to system ram */
        if (!atomic && fb) {
                ast_fb = to_ast_framebuffer(fb);
                obj = ast_fb->obj;
                bo = gem_to_ast_bo(obj);
                ret = ast_bo_reserve(bo, false);
                if (ret)
                        return ret;
                ast_bo_push_sysram(bo);
                ast_bo_unreserve(bo);
        }

        ast_fb = to_ast_framebuffer(crtc->fb);
        obj = ast_fb->obj;
        bo = gem_to_ast_bo(obj);

        ret = ast_bo_reserve(bo, false);
        if (ret)
                return ret;

        ret = ast_bo_pin(bo, TTM_PL_FLAG_VRAM, &gpu_addr);
        if (ret) {
                ast_bo_unreserve(bo);
                return ret;
        }

        if (&ast->fbdev->afb == ast_fb) {
                /* if pushing console in kmap it */
                ret = ttm_bo_kmap(&bo->bo, 0, bo->bo.num_pages, &bo->kmap);
                if (ret)
                        DRM_ERROR("failed to kmap fbcon\n");
        }
        ast_bo_unreserve(bo);

        ast_set_start_address_crt1(crtc, (u32)gpu_addr);

        return 0;
}

static int ast_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
                             struct drm_framebuffer *old_fb)
{
        return ast_crtc_do_set_base(crtc, old_fb, x, y, 0);
}

static int ast_crtc_mode_set(struct drm_crtc *crtc,
                             struct drm_display_mode *mode,
                             struct drm_display_mode *adjusted_mode,
                             int x, int y,
                             struct drm_framebuffer *old_fb)
{
        struct drm_device *dev = crtc->dev;
        struct ast_private *ast = crtc->dev->dev_private;
        struct ast_vbios_mode_info vbios_mode;
        bool ret;
        if (ast->chip == AST1180) {
                DRM_ERROR("AST 1180 modesetting not supported\n");
                return -EINVAL;
        }

        ret = ast_get_vbios_mode_info(crtc, mode, adjusted_mode, &vbios_mode);
        if (ret == false)
                return -EINVAL;
        ast_open_key(ast);

        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xa1, 0xff, 0x04);

        ast_set_std_reg(crtc, adjusted_mode, &vbios_mode);
        ast_set_crtc_reg(crtc, adjusted_mode, &vbios_mode);
        ast_set_offset_reg(crtc);
        ast_set_dclk_reg(dev, adjusted_mode, &vbios_mode);
        ast_set_ext_reg(crtc, adjusted_mode, &vbios_mode);
        ast_set_sync_reg(dev, adjusted_mode, &vbios_mode);
        ast_set_dac_reg(crtc, adjusted_mode, &vbios_mode);

        ast_crtc_mode_set_base(crtc, x, y, old_fb);

        return 0;
}

static void ast_crtc_disable(struct drm_crtc *crtc)
{

}

static void ast_crtc_prepare(struct drm_crtc *crtc)
{

}

static void ast_crtc_commit(struct drm_crtc *crtc)
{
        struct ast_private *ast = crtc->dev->dev_private;
        ast_set_index_reg_mask(ast, AST_IO_SEQ_PORT, 0x1, 0xdf, 0);
}


static const struct drm_crtc_helper_funcs ast_crtc_helper_funcs = {
        .dpms = ast_crtc_dpms,
        .mode_fixup = ast_crtc_mode_fixup,
        .mode_set = ast_crtc_mode_set,
        .mode_set_base = ast_crtc_mode_set_base,
        .disable = ast_crtc_disable,
        .load_lut = ast_crtc_load_lut,
        .prepare = ast_crtc_prepare,
        .commit = ast_crtc_commit,

};

static void ast_crtc_reset(struct drm_crtc *crtc)
{

}

static void ast_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
                                 u16 *blue, uint32_t start, uint32_t size)
{
        struct ast_crtc *ast_crtc = to_ast_crtc(crtc);
        int end = (start + size > 256) ? 256 : start + size, i;

        /* userspace palettes are always correct as is */
        for (i = start; i < end; i++) {
                ast_crtc->lut_r[i] = red[i] >> 8;
                ast_crtc->lut_g[i] = green[i] >> 8;
                ast_crtc->lut_b[i] = blue[i] >> 8;
        }
        ast_crtc_load_lut(crtc);
}


static void ast_crtc_destroy(struct drm_crtc *crtc)
{
        drm_crtc_cleanup(crtc);
        kfree(crtc);
}

static const struct drm_crtc_funcs ast_crtc_funcs = {
        .cursor_set = ast_cursor_set,
        .cursor_move = ast_cursor_move,
        .reset = ast_crtc_reset,
        .set_config = drm_crtc_helper_set_config,
        .gamma_set = ast_crtc_gamma_set,
        .destroy = ast_crtc_destroy,
};

int ast_crtc_init(struct drm_device *dev)
{
        struct ast_crtc *crtc;
        int i;

        crtc = kzalloc(sizeof(struct ast_crtc), GFP_KERNEL);
        if (!crtc)
                return -ENOMEM;

        drm_crtc_init(dev, &crtc->base, &ast_crtc_funcs);
        drm_mode_crtc_set_gamma_size(&crtc->base, 256);
        drm_crtc_helper_add(&crtc->base, &ast_crtc_helper_funcs);

        for (i = 0; i < 256; i++) {
                crtc->lut_r[i] = i;
                crtc->lut_g[i] = i;
                crtc->lut_b[i] = i;
        }
        return 0;
}

static void ast_encoder_destroy(struct drm_encoder *encoder)
{
        drm_encoder_cleanup(encoder);
        kfree(encoder);
}


static struct drm_encoder *ast_best_single_encoder(struct drm_connector *connector)
{
        int enc_id = connector->encoder_ids[0];
        struct drm_mode_object *obj;
        struct drm_encoder *encoder;

        /* pick the encoder ids */
        if (enc_id) {
                obj = drm_mode_object_find(connector->dev, enc_id, DRM_MODE_OBJECT_ENCODER);
                if (!obj)
                        return NULL;
                encoder = obj_to_encoder(obj);
                return encoder;
        }
        return NULL;
}


static const struct drm_encoder_funcs ast_enc_funcs = {
        .destroy = ast_encoder_destroy,
};

static void ast_encoder_dpms(struct drm_encoder *encoder, int mode)
{

}

static bool ast_mode_fixup(struct drm_encoder *encoder,
                           const struct drm_display_mode *mode,
                           struct drm_display_mode *adjusted_mode)
{
        return true;
}

static void ast_encoder_mode_set(struct drm_encoder *encoder,
                               struct drm_display_mode *mode,
                               struct drm_display_mode *adjusted_mode)
{
}

static void ast_encoder_prepare(struct drm_encoder *encoder)
{

}

static void ast_encoder_commit(struct drm_encoder *encoder)
{

}


static const struct drm_encoder_helper_funcs ast_enc_helper_funcs = {
        .dpms = ast_encoder_dpms,
        .mode_fixup = ast_mode_fixup,
        .prepare = ast_encoder_prepare,
        .commit = ast_encoder_commit,
        .mode_set = ast_encoder_mode_set,
};

int ast_encoder_init(struct drm_device *dev)
{
        struct ast_encoder *ast_encoder;

        ast_encoder = kzalloc(sizeof(struct ast_encoder), GFP_KERNEL);
        if (!ast_encoder)
                return -ENOMEM;

        drm_encoder_init(dev, &ast_encoder->base, &ast_enc_funcs,
                         DRM_MODE_ENCODER_DAC);
        drm_encoder_helper_add(&ast_encoder->base, &ast_enc_helper_funcs);

        ast_encoder->base.possible_crtcs = 1;
        return 0;
}

static int ast_get_modes(struct drm_connector *connector)
{
        struct ast_connector *ast_connector = to_ast_connector(connector);
        struct edid *edid;
        int ret;

        edid = drm_get_edid(connector, &ast_connector->i2c->adapter);
        if (edid) {
                drm_mode_connector_update_edid_property(&ast_connector->base, edid);
                ret = drm_add_edid_modes(connector, edid);
                kfree(edid);
                return ret;
        } else
                drm_mode_connector_update_edid_property(&ast_connector->base, NULL);
        return 0;
}

static int ast_mode_valid(struct drm_connector *connector,
                          struct drm_display_mode *mode)
{
        return MODE_OK;
}

static void ast_connector_destroy(struct drm_connector *connector)
{
        struct ast_connector *ast_connector = to_ast_connector(connector);
        ast_i2c_destroy(ast_connector->i2c);
        drm_sysfs_connector_remove(connector);
        drm_connector_cleanup(connector);
        kfree(connector);
}

static enum drm_connector_status
ast_connector_detect(struct drm_connector *connector, bool force)
{
        return connector_status_connected;
}

static const struct drm_connector_helper_funcs ast_connector_helper_funcs = {
        .mode_valid = ast_mode_valid,
        .get_modes = ast_get_modes,
        .best_encoder = ast_best_single_encoder,
};

static const struct drm_connector_funcs ast_connector_funcs = {
        .dpms = drm_helper_connector_dpms,
        .detect = ast_connector_detect,
        .fill_modes = drm_helper_probe_single_connector_modes,
        .destroy = ast_connector_destroy,
};

int ast_connector_init(struct drm_device *dev)
{
        struct ast_connector *ast_connector;
        struct drm_connector *connector;
        struct drm_encoder *encoder;

        ast_connector = kzalloc(sizeof(struct ast_connector), GFP_KERNEL);
        if (!ast_connector)
                return -ENOMEM;

        connector = &ast_connector->base;
        drm_connector_init(dev, connector, &ast_connector_funcs, DRM_MODE_CONNECTOR_VGA);

        drm_connector_helper_add(connector, &ast_connector_helper_funcs);

        connector->interlace_allowed = 0;
        connector->doublescan_allowed = 0;

        drm_sysfs_connector_add(connector);

        connector->polled = DRM_CONNECTOR_POLL_CONNECT;

        encoder = list_first_entry(&dev->mode_config.encoder_list, struct drm_encoder, head);
        drm_mode_connector_attach_encoder(connector, encoder);

        ast_connector->i2c = ast_i2c_create(dev);
        if (!ast_connector->i2c)
                DRM_ERROR("failed to add ddc bus for connector\n");

        return 0;
}

/* allocate cursor cache and pin at start of VRAM */
int ast_cursor_init(struct drm_device *dev)
{
        struct ast_private *ast = dev->dev_private;
        int size;
        int ret;
        struct drm_gem_object *obj;
        struct ast_bo *bo;
        uint64_t gpu_addr;

        size = (AST_HWC_SIZE + AST_HWC_SIGNATURE_SIZE) * AST_DEFAULT_HWC_NUM;

        ret = ast_gem_create(dev, size, true, &obj);
        if (ret)
                return ret;
        bo = gem_to_ast_bo(obj);
        ret = ast_bo_reserve(bo, false);
        if (unlikely(ret != 0))
                goto fail;

        ret = ast_bo_pin(bo, TTM_PL_FLAG_VRAM, &gpu_addr);
        ast_bo_unreserve(bo);
        if (ret)
                goto fail;

        /* kmap the object */
        ret = ttm_bo_kmap(&bo->bo, 0, bo->bo.num_pages, &ast->cache_kmap);
        if (ret)
                goto fail;

        ast->cursor_cache = obj;
        ast->cursor_cache_gpu_addr = gpu_addr;
        DRM_DEBUG_KMS("pinned cursor cache at %llx\n", ast->cursor_cache_gpu_addr);
        return 0;
fail:
        return ret;
}

void ast_cursor_fini(struct drm_device *dev)
{
        struct ast_private *ast = dev->dev_private;
        ttm_bo_kunmap(&ast->cache_kmap);
        drm_gem_object_unreference_unlocked(ast->cursor_cache);
}

int ast_mode_init(struct drm_device *dev)
{
        ast_cursor_init(dev);
        ast_crtc_init(dev);
        ast_encoder_init(dev);
        ast_connector_init(dev);
        return 0;
}

void ast_mode_fini(struct drm_device *dev)
{
        ast_cursor_fini(dev);
}

static int get_clock(void *i2c_priv)
{
        struct ast_i2c_chan *i2c = i2c_priv;
        struct ast_private *ast = i2c->dev->dev_private;
        uint32_t val;

        val = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4;
        return val & 1 ? 1 : 0;
}

static int get_data(void *i2c_priv)
{
        struct ast_i2c_chan *i2c = i2c_priv;
        struct ast_private *ast = i2c->dev->dev_private;
        uint32_t val;

        val = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5;
        return val & 1 ? 1 : 0;
}

static void set_clock(void *i2c_priv, int clock)
{
        struct ast_i2c_chan *i2c = i2c_priv;
        struct ast_private *ast = i2c->dev->dev_private;
        int i;
        u8 ujcrb7, jtemp;

        for (i = 0; i < 0x10000; i++) {
                ujcrb7 = ((clock & 0x01) ? 0 : 1);
                ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xfe, ujcrb7);
                jtemp = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x01);
                if (ujcrb7 == jtemp)
                        break;
        }
}

static void set_data(void *i2c_priv, int data)
{
        struct ast_i2c_chan *i2c = i2c_priv;
        struct ast_private *ast = i2c->dev->dev_private;
        int i;
        u8 ujcrb7, jtemp;

        for (i = 0; i < 0x10000; i++) {
                ujcrb7 = ((data & 0x01) ? 0 : 1) << 2;
                ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xfb, ujcrb7);
                jtemp = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x04);
                if (ujcrb7 == jtemp)
                        break;
        }
}

static struct ast_i2c_chan *ast_i2c_create(struct drm_device *dev)
{
        struct ast_i2c_chan *i2c;
        int ret;

        i2c = kzalloc(sizeof(struct ast_i2c_chan), GFP_KERNEL);
        if (!i2c)
                return NULL;

        i2c->adapter.owner = THIS_MODULE;
        i2c->adapter.class = I2C_CLASS_DDC;
        i2c->adapter.dev.parent = &dev->pdev->dev;
        i2c->dev = dev;
        i2c_set_adapdata(&i2c->adapter, i2c);
        snprintf(i2c->adapter.name, sizeof(i2c->adapter.name),
                 "AST i2c bit bus");
        i2c->adapter.algo_data = &i2c->bit;

        i2c->bit.udelay = 20;
        i2c->bit.timeout = 2;
        i2c->bit.data = i2c;
        i2c->bit.setsda = set_data;
        i2c->bit.setscl = set_clock;
        i2c->bit.getsda = get_data;
        i2c->bit.getscl = get_clock;
        ret = i2c_bit_add_bus(&i2c->adapter);
        if (ret) {
                DRM_ERROR("Failed to register bit i2c\n");
                goto out_free;
        }

        return i2c;
out_free:
        kfree(i2c);
        return NULL;
}

static void ast_i2c_destroy(struct ast_i2c_chan *i2c)
{
        if (!i2c)
                return;
        i2c_del_adapter(&i2c->adapter);
        kfree(i2c);
}

void ast_show_cursor(struct drm_crtc *crtc)
{
        struct ast_private *ast = crtc->dev->dev_private;
        u8 jreg;

        jreg = 0x2;
        /* enable ARGB cursor */
        jreg |= 1;
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xcb, 0xfc, jreg);
}

void ast_hide_cursor(struct drm_crtc *crtc)
{
        struct ast_private *ast = crtc->dev->dev_private;
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xcb, 0xfc, 0x00);
}

static u32 copy_cursor_image(u8 *src, u8 *dst, int width, int height)
{
        union {
                u32 ul;
                u8 b[4];
        } srcdata32[2], data32;
        union {
                u16 us;
                u8 b[2];
        } data16;
        u32 csum = 0;
        s32 alpha_dst_delta, last_alpha_dst_delta;
        u8 *srcxor, *dstxor;
        int i, j;
        u32 per_pixel_copy, two_pixel_copy;

        alpha_dst_delta = AST_MAX_HWC_WIDTH << 1;
        last_alpha_dst_delta = alpha_dst_delta - (width << 1);

        srcxor = src;
        dstxor = (u8 *)dst + last_alpha_dst_delta + (AST_MAX_HWC_HEIGHT - height) * alpha_dst_delta;
        per_pixel_copy = width & 1;
        two_pixel_copy = width >> 1;

        for (j = 0; j < height; j++) {
                for (i = 0; i < two_pixel_copy; i++) {
                        srcdata32[0].ul = *((u32 *)srcxor) & 0xf0f0f0f0;
                        srcdata32[1].ul = *((u32 *)(srcxor + 4)) & 0xf0f0f0f0;
                        data32.b[0] = srcdata32[0].b[1] | (srcdata32[0].b[0] >> 4);
                        data32.b[1] = srcdata32[0].b[3] | (srcdata32[0].b[2] >> 4);
                        data32.b[2] = srcdata32[0].b[1] | (srcdata32[1].b[0] >> 4);
                        data32.b[3] = srcdata32[0].b[3] | (srcdata32[1].b[2] >> 4);

                        writel(data32.ul, dstxor);
                        csum += data32.ul;

                        dstxor += 4;
                        srcxor += 8;

                }

                for (i = 0; i < per_pixel_copy; i++) {
                        srcdata32[0].ul = *((u32 *)srcxor) & 0xf0f0f0f0;
                        data16.b[0] = srcdata32[0].b[1] | (srcdata32[0].b[0] >> 4);
                        data16.b[1] = srcdata32[0].b[3] | (srcdata32[0].b[2] >> 4);
                        writew(data16.us, dstxor);
                        csum += (u32)data16.us;

                        dstxor += 2;
                        srcxor += 4;
                }
                dstxor += last_alpha_dst_delta;
        }
        return csum;
}

static int ast_cursor_set(struct drm_crtc *crtc,
                          struct drm_file *file_priv,
                          uint32_t handle,
                          uint32_t width,
                          uint32_t height)
{
        struct ast_private *ast = crtc->dev->dev_private;
        struct ast_crtc *ast_crtc = to_ast_crtc(crtc);
        struct drm_gem_object *obj;
        struct ast_bo *bo;
        uint64_t gpu_addr;
        u32 csum;
        int ret;
        struct ttm_bo_kmap_obj uobj_map;
        u8 *src, *dst;
        bool src_isiomem, dst_isiomem;
        if (!handle) {
                ast_hide_cursor(crtc);
                return 0;
        }

        if (width > AST_MAX_HWC_WIDTH || height > AST_MAX_HWC_HEIGHT)
                return -EINVAL;

        obj = drm_gem_object_lookup(crtc->dev, file_priv, handle);
        if (!obj) {
                DRM_ERROR("Cannot find cursor object %x for crtc\n", handle);
                return -ENOENT;
        }
        bo = gem_to_ast_bo(obj);

        ret = ast_bo_reserve(bo, false);
        if (ret)
                goto fail;

        ret = ttm_bo_kmap(&bo->bo, 0, bo->bo.num_pages, &uobj_map);

        src = ttm_kmap_obj_virtual(&uobj_map, &src_isiomem);
        dst = ttm_kmap_obj_virtual(&ast->cache_kmap, &dst_isiomem);

        if (src_isiomem == true)
                DRM_ERROR("src cursor bo should be in main memory\n");
        if (dst_isiomem == false)
                DRM_ERROR("dst bo should be in VRAM\n");

        dst += (AST_HWC_SIZE + AST_HWC_SIGNATURE_SIZE)*ast->next_cursor;

        /* do data transfer to cursor cache */
        csum = copy_cursor_image(src, dst, width, height);

        /* write checksum + signature */
        ttm_bo_kunmap(&uobj_map);
        ast_bo_unreserve(bo);
        {
                u8 *dst = (u8 *)ast->cache_kmap.virtual + (AST_HWC_SIZE + AST_HWC_SIGNATURE_SIZE)*ast->next_cursor + AST_HWC_SIZE;
                writel(csum, dst);
                writel(width, dst + AST_HWC_SIGNATURE_SizeX);
                writel(height, dst + AST_HWC_SIGNATURE_SizeY);
                writel(0, dst + AST_HWC_SIGNATURE_HOTSPOTX);
                writel(0, dst + AST_HWC_SIGNATURE_HOTSPOTY);

                /* set pattern offset */
                gpu_addr = ast->cursor_cache_gpu_addr;
                gpu_addr += (AST_HWC_SIZE + AST_HWC_SIGNATURE_SIZE)*ast->next_cursor;
                gpu_addr >>= 3;
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xc8, gpu_addr & 0xff);
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xc9, (gpu_addr >> 8) & 0xff);
                ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xca, (gpu_addr >> 16) & 0xff);
        }
        ast_crtc->cursor_width = width;
        ast_crtc->cursor_height = height;
        ast_crtc->offset_x = AST_MAX_HWC_WIDTH - width;
        ast_crtc->offset_y = AST_MAX_HWC_WIDTH - height;

        ast->next_cursor = (ast->next_cursor + 1) % AST_DEFAULT_HWC_NUM;

        ast_show_cursor(crtc);

        drm_gem_object_unreference_unlocked(obj);
        return 0;
fail:
        drm_gem_object_unreference_unlocked(obj);
        return ret;
}

static int ast_cursor_move(struct drm_crtc *crtc,
                           int x, int y)
{
        struct ast_crtc *ast_crtc = to_ast_crtc(crtc);
        struct ast_private *ast = crtc->dev->dev_private;
        int x_offset, y_offset;
        u8 *sig;

        sig = (u8 *)ast->cache_kmap.virtual + (AST_HWC_SIZE + AST_HWC_SIGNATURE_SIZE)*ast->next_cursor + AST_HWC_SIZE;
        writel(x, sig + AST_HWC_SIGNATURE_X);
        writel(y, sig + AST_HWC_SIGNATURE_Y);

        x_offset = ast_crtc->offset_x;
        y_offset = ast_crtc->offset_y;
        if (x < 0) {
                x_offset = (-x) + ast_crtc->offset_x;
                x = 0;
        }

        if (y < 0) {
                y_offset = (-y) + ast_crtc->offset_y;
                y = 0;
        }
        ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xc2, x_offset);
        ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xc3, y_offset);
        ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xc4, (x & 0xff));
        ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xc5, ((x >> 8) & 0x0f));
        ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xc6, (y & 0xff));
        ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xc7, ((y >> 8) & 0x07));

        /* dummy write to fire HWC */
        ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xCB, 0xFF, 0x00);

        return 0;
}