/*
 * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
 * Author: Rob Clark <rob@ti.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/seq_file.h>

#include <drm/drm_crtc.h>
#include <drm/drm_crtc_helper.h>

#include "omap_dmm_tiler.h"
#include "omap_drv.h"

/*
 * framebuffer funcs
 */

static const u32 formats[] = {
        /* 16bpp [A]RGB: */
        DRM_FORMAT_RGB565, /* RGB16-565 */
        DRM_FORMAT_RGBX4444, /* RGB12x-4444 */
        DRM_FORMAT_XRGB4444, /* xRGB12-4444 */
        DRM_FORMAT_RGBA4444, /* RGBA12-4444 */
        DRM_FORMAT_ARGB4444, /* ARGB16-4444 */
        DRM_FORMAT_XRGB1555, /* xRGB15-1555 */
        DRM_FORMAT_ARGB1555, /* ARGB16-1555 */
        /* 24bpp RGB: */
        DRM_FORMAT_RGB888,   /* RGB24-888 */
        /* 32bpp [A]RGB: */
        DRM_FORMAT_RGBX8888, /* RGBx24-8888 */
        DRM_FORMAT_XRGB8888, /* xRGB24-8888 */
        DRM_FORMAT_RGBA8888, /* RGBA32-8888 */
        DRM_FORMAT_ARGB8888, /* ARGB32-8888 */
        /* YUV: */
        DRM_FORMAT_NV12,
        DRM_FORMAT_YUYV,
        DRM_FORMAT_UYVY,
};

/* per-plane info for the fb: */
struct plane {
        struct drm_gem_object *bo;
        uint32_t pitch;
        uint32_t offset;
        dma_addr_t dma_addr;
};

#define to_omap_framebuffer(x) container_of(x, struct omap_framebuffer, base)

struct omap_framebuffer {
        struct drm_framebuffer base;
        int pin_count;
        const struct drm_format_info *format;
        struct plane planes[2];
        /* lock for pinning (pin_count and planes.dma_addr) */
        struct mutex lock;
};

static int omap_framebuffer_create_handle(struct drm_framebuffer *fb,
                struct drm_file *file_priv,
                unsigned int *handle)
{
        struct omap_framebuffer *omap_fb = to_omap_framebuffer(fb);
        return drm_gem_handle_create(file_priv,
                        omap_fb->planes[0].bo, handle);
}

static void omap_framebuffer_destroy(struct drm_framebuffer *fb)
{
        struct omap_framebuffer *omap_fb = to_omap_framebuffer(fb);
        int i, n = fb->format->num_planes;

        DBG("destroy: FB ID: %d (%p)", fb->base.id, fb);

        drm_framebuffer_cleanup(fb);

        for (i = 0; i < n; i++) {
                struct plane *plane = &omap_fb->planes[i];

                drm_gem_object_unreference_unlocked(plane->bo);
        }

        kfree(omap_fb);
}

static const struct drm_framebuffer_funcs omap_framebuffer_funcs = {
        .create_handle = omap_framebuffer_create_handle,
        .destroy = omap_framebuffer_destroy,
};

static uint32_t get_linear_addr(struct plane *plane,
                const struct drm_format_info *format, int n, int x, int y)
{
        uint32_t offset;

        offset = plane->offset
               + (x * format->cpp[n] / (n == 0 ? 1 : format->hsub))
               + (y * plane->pitch / (n == 0 ? 1 : format->vsub));

        return plane->dma_addr + offset;
}

bool omap_framebuffer_supports_rotation(struct drm_framebuffer *fb)
{
        struct omap_framebuffer *omap_fb = to_omap_framebuffer(fb);
        struct plane *plane = &omap_fb->planes[0];

        return omap_gem_flags(plane->bo) & OMAP_BO_TILED;
}

/* Note: DRM rotates counter-clockwise, TILER & DSS rotates clockwise */
static uint32_t drm_rotation_to_tiler(unsigned int drm_rot)
{
        uint32_t orient;

        switch (drm_rot & DRM_MODE_ROTATE_MASK) {
        default:
        case DRM_MODE_ROTATE_0:
                orient = 0;
                break;
        case DRM_MODE_ROTATE_90:
                orient = MASK_XY_FLIP | MASK_X_INVERT;
                break;
        case DRM_MODE_ROTATE_180:
                orient = MASK_X_INVERT | MASK_Y_INVERT;
                break;
        case DRM_MODE_ROTATE_270:
                orient = MASK_XY_FLIP | MASK_Y_INVERT;
                break;
        }

        if (drm_rot & DRM_MODE_REFLECT_X)
                orient ^= MASK_X_INVERT;

        if (drm_rot & DRM_MODE_REFLECT_Y)
                orient ^= MASK_Y_INVERT;

        return orient;
}

/* update ovl info for scanout, handles cases of multi-planar fb's, etc.
 */
void omap_framebuffer_update_scanout(struct drm_framebuffer *fb,
                struct drm_plane_state *state, struct omap_overlay_info *info)
{
        struct omap_framebuffer *omap_fb = to_omap_framebuffer(fb);
        const struct drm_format_info *format = omap_fb->format;
        struct plane *plane = &omap_fb->planes[0];
        uint32_t x, y, orient = 0;

        info->fourcc = fb->format->format;

        info->pos_x      = state->crtc_x;
        info->pos_y      = state->crtc_y;
        info->out_width  = state->crtc_w;
        info->out_height = state->crtc_h;
        info->width      = state->src_w >> 16;
        info->height     = state->src_h >> 16;

        /* DSS driver wants the w & h in rotated orientation */
        if (drm_rotation_90_or_270(state->rotation))
                swap(info->width, info->height);

        x = state->src_x >> 16;
        y = state->src_y >> 16;

        if (omap_gem_flags(plane->bo) & OMAP_BO_TILED) {
                uint32_t w = state->src_w >> 16;
                uint32_t h = state->src_h >> 16;

                orient = drm_rotation_to_tiler(state->rotation);

                /*
                 * omap_gem_rotated_paddr() wants the x & y in tiler units.
                 * Usually tiler unit size is the same as the pixel size, except
                 * for YUV422 formats, for which the tiler unit size is 32 bits
                 * and pixel size is 16 bits.
                 */
                if (fb->format->format == DRM_FORMAT_UYVY ||
                                fb->format->format == DRM_FORMAT_YUYV) {
                        x /= 2;
                        w /= 2;
                }

                /* adjust x,y offset for invert: */
                if (orient & MASK_Y_INVERT)
                        y += h - 1;
                if (orient & MASK_X_INVERT)
                        x += w - 1;

                /* Note: x and y are in TILER units, not pixels */
                omap_gem_rotated_dma_addr(plane->bo, orient, x, y,
                                          &info->paddr);
                info->rotation_type = OMAP_DSS_ROT_TILER;
                info->rotation = state->rotation ?: DRM_MODE_ROTATE_0;
                /* Note: stride in TILER units, not pixels */
                info->screen_width  = omap_gem_tiled_stride(plane->bo, orient);
        } else {
                switch (state->rotation & DRM_MODE_ROTATE_MASK) {
                case 0:
                case DRM_MODE_ROTATE_0:
                        /* OK */
                        break;

                default:
                        dev_warn(fb->dev->dev,
                                "rotation '%d' ignored for non-tiled fb\n",
                                state->rotation);
                        break;
                }

                info->paddr         = get_linear_addr(plane, format, 0, x, y);
                info->rotation_type = OMAP_DSS_ROT_NONE;
                info->rotation      = DRM_MODE_ROTATE_0;
                info->screen_width  = plane->pitch;
        }

        /* convert to pixels: */
        info->screen_width /= format->cpp[0];

        if (fb->format->format == DRM_FORMAT_NV12) {
                plane = &omap_fb->planes[1];

                if (info->rotation_type == OMAP_DSS_ROT_TILER) {
                        WARN_ON(!(omap_gem_flags(plane->bo) & OMAP_BO_TILED));
                        omap_gem_rotated_dma_addr(plane->bo, orient, x/2, y/2,
                                                  &info->p_uv_addr);
                } else {
                        info->p_uv_addr = get_linear_addr(plane, format, 1, x, y);
                }
        } else {
                info->p_uv_addr = 0;
        }
}

/* pin, prepare for scanout: */
int omap_framebuffer_pin(struct drm_framebuffer *fb)
{
        struct omap_framebuffer *omap_fb = to_omap_framebuffer(fb);
        int ret, i, n = fb->format->num_planes;

        mutex_lock(&omap_fb->lock);

        if (omap_fb->pin_count > 0) {
                omap_fb->pin_count++;
                mutex_unlock(&omap_fb->lock);
                return 0;
        }

        for (i = 0; i < n; i++) {
                struct plane *plane = &omap_fb->planes[i];
                ret = omap_gem_pin(plane->bo, &plane->dma_addr);
                if (ret)
                        goto fail;
                omap_gem_dma_sync_buffer(plane->bo, DMA_TO_DEVICE);
        }

        omap_fb->pin_count++;

        mutex_unlock(&omap_fb->lock);

        return 0;

fail:
        for (i--; i >= 0; i--) {
                struct plane *plane = &omap_fb->planes[i];
                omap_gem_unpin(plane->bo);
                plane->dma_addr = 0;
        }

        mutex_unlock(&omap_fb->lock);

        return ret;
}

/* unpin, no longer being scanned out: */
void omap_framebuffer_unpin(struct drm_framebuffer *fb)
{
        struct omap_framebuffer *omap_fb = to_omap_framebuffer(fb);
        int i, n = fb->format->num_planes;

        mutex_lock(&omap_fb->lock);

        omap_fb->pin_count--;

        if (omap_fb->pin_count > 0) {
                mutex_unlock(&omap_fb->lock);
                return;
        }

        for (i = 0; i < n; i++) {
                struct plane *plane = &omap_fb->planes[i];
                omap_gem_unpin(plane->bo);
                plane->dma_addr = 0;
        }

        mutex_unlock(&omap_fb->lock);
}

/* iterate thru all the connectors, returning ones that are attached
 * to the same fb..
 */
struct drm_connector *omap_framebuffer_get_next_connector(
                struct drm_framebuffer *fb, struct drm_connector *from)
{
        struct drm_device *dev = fb->dev;
        struct list_head *connector_list = &dev->mode_config.connector_list;
        struct drm_connector *connector = from;

        if (!from)
                return list_first_entry_or_null(connector_list, typeof(*from),
                                                head);

        list_for_each_entry_from(connector, connector_list, head) {
                if (connector != from) {
                        struct drm_encoder *encoder = connector->encoder;
                        struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
                        if (crtc && crtc->primary->fb == fb)
                                return connector;

                }
        }

        return NULL;
}

#ifdef CONFIG_DEBUG_FS
void omap_framebuffer_describe(struct drm_framebuffer *fb, struct seq_file *m)
{
        struct omap_framebuffer *omap_fb = to_omap_framebuffer(fb);
        int i, n = fb->format->num_planes;

        seq_printf(m, "fb: %dx%d@%4.4s\n", fb->width, fb->height,
                        (char *)&fb->format->format);

        for (i = 0; i < n; i++) {
                struct plane *plane = &omap_fb->planes[i];
                seq_printf(m, "   %d: offset=%d pitch=%d, obj: ",
                                i, plane->offset, plane->pitch);
                omap_gem_describe(plane->bo, m);
        }
}
#endif

struct drm_framebuffer *omap_framebuffer_create(struct drm_device *dev,
                struct drm_file *file, const struct drm_mode_fb_cmd2 *mode_cmd)
{
        unsigned int num_planes = drm_format_num_planes(mode_cmd->pixel_format);
        struct drm_gem_object *bos[4];
        struct drm_framebuffer *fb;
        int i;

        for (i = 0; i < num_planes; i++) {
                bos[i] = drm_gem_object_lookup(file, mode_cmd->handles[i]);
                if (!bos[i]) {
                        fb = ERR_PTR(-ENOENT);
                        goto error;
                }
        }

        fb = omap_framebuffer_init(dev, mode_cmd, bos);
        if (IS_ERR(fb))
                goto error;

        return fb;

error:
        while (--i >= 0)
                drm_gem_object_unreference_unlocked(bos[i]);

        return fb;
}

struct drm_framebuffer *omap_framebuffer_init(struct drm_device *dev,
                const struct drm_mode_fb_cmd2 *mode_cmd, struct drm_gem_object **bos)
{
        const struct drm_format_info *format = NULL;
        struct omap_framebuffer *omap_fb = NULL;
        struct drm_framebuffer *fb = NULL;
        unsigned int pitch = mode_cmd->pitches[0];
        int ret, i;

        DBG("create framebuffer: dev=%p, mode_cmd=%p (%dx%d@%4.4s)",
                        dev, mode_cmd, mode_cmd->width, mode_cmd->height,
                        (char *)&mode_cmd->pixel_format);

        format = drm_format_info(mode_cmd->pixel_format);

        for (i = 0; i < ARRAY_SIZE(formats); i++) {
                if (formats[i] == mode_cmd->pixel_format)
                        break;
        }

        if (!format || i == ARRAY_SIZE(formats)) {
                dev_dbg(dev->dev, "unsupported pixel format: %4.4s\n",
                        (char *)&mode_cmd->pixel_format);
                ret = -EINVAL;
                goto fail;
        }

        omap_fb = kzalloc(sizeof(*omap_fb), GFP_KERNEL);
        if (!omap_fb) {
                ret = -ENOMEM;
                goto fail;
        }

        fb = &omap_fb->base;
        omap_fb->format = format;
        mutex_init(&omap_fb->lock);

        /*
         * The code below assumes that no format use more than two planes, and
         * that the two planes of multiplane formats need the same number of
         * bytes per pixel.
         */
        if (format->num_planes == 2 && pitch != mode_cmd->pitches[1]) {
                dev_dbg(dev->dev, "pitches differ between planes 0 and 1\n");
                ret = -EINVAL;
                goto fail;
        }

        if (pitch % format->cpp[0]) {
                dev_dbg(dev->dev,
                        "buffer pitch (%u bytes) is not a multiple of pixel size (%u bytes)\n",
                        pitch, format->cpp[0]);
                ret = -EINVAL;
                goto fail;
        }

        for (i = 0; i < format->num_planes; i++) {
                struct plane *plane = &omap_fb->planes[i];
                unsigned int vsub = i == 0 ? 1 : format->vsub;
                unsigned int size;

                size = pitch * mode_cmd->height / vsub;

                if (size > omap_gem_mmap_size(bos[i]) - mode_cmd->offsets[i]) {
                        dev_dbg(dev->dev,
                                "provided buffer object is too small! %zu < %d\n",
                                bos[i]->size - mode_cmd->offsets[i], size);
                        ret = -EINVAL;
                        goto fail;
                }

                plane->bo     = bos[i];
                plane->offset = mode_cmd->offsets[i];
                plane->pitch  = pitch;
                plane->dma_addr  = 0;
        }

        drm_helper_mode_fill_fb_struct(dev, fb, mode_cmd);

        ret = drm_framebuffer_init(dev, fb, &omap_framebuffer_funcs);
        if (ret) {
                dev_err(dev->dev, "framebuffer init failed: %d\n", ret);
                goto fail;
        }

        DBG("create: FB ID: %d (%p)", fb->base.id, fb);

        return fb;

fail:
        kfree(omap_fb);

        return ERR_PTR(ret);
}