/*
 * Copyright © 2007 David Airlie
 *
 * 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, sublicense,
 * 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 above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * 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 NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS 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.
 *
 * Authors:
 *     David Airlie
 */

#include <linux/fb.h>
#include <linux/pci.h>
#include <linux/pm_runtime.h>
#include <linux/vga_switcheroo.h>

#include <drm/drm_crtc_helper.h>
#include <drm/drm_drv.h>
#include <drm/drm_fb_helper.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_framebuffer.h>
#include <drm/drm_gem_framebuffer_helper.h>

#include "radeon.h"

static void radeon_fbdev_destroy_pinned_object(struct drm_gem_object *gobj)
{
        struct radeon_bo *rbo = gem_to_radeon_bo(gobj);
        int ret;

        ret = radeon_bo_reserve(rbo, false);
        if (likely(ret == 0)) {
                radeon_bo_kunmap(rbo);
                radeon_bo_unpin(rbo);
                radeon_bo_unreserve(rbo);
        }
        drm_gem_object_put(gobj);
}

static int radeon_fbdev_create_pinned_object(struct drm_fb_helper *fb_helper,
                                             const struct drm_format_info *info,
                                             struct drm_mode_fb_cmd2 *mode_cmd,
                                             struct drm_gem_object **gobj_p)
{
        struct radeon_device *rdev = fb_helper->dev->dev_private;
        struct drm_gem_object *gobj = NULL;
        struct radeon_bo *rbo = NULL;
        bool fb_tiled = false; /* useful for testing */
        u32 tiling_flags = 0;
        int ret;
        int aligned_size, size;
        int height = mode_cmd->height;
        u32 cpp;

        cpp = info->cpp[0];

        /* need to align pitch with crtc limits */
        mode_cmd->pitches[0] = radeon_align_pitch(rdev, mode_cmd->width, cpp,
                                                  fb_tiled);

        if (rdev->family >= CHIP_R600)
                height = ALIGN(mode_cmd->height, 8);
        size = mode_cmd->pitches[0] * height;
        aligned_size = ALIGN(size, PAGE_SIZE);
        ret = radeon_gem_object_create(rdev, aligned_size, 0,
                                       RADEON_GEM_DOMAIN_VRAM,
                                       0, true, &gobj);
        if (ret) {
                pr_err("failed to allocate framebuffer (%d)\n", aligned_size);
                return -ENOMEM;
        }
        rbo = gem_to_radeon_bo(gobj);

        if (fb_tiled)
                tiling_flags = RADEON_TILING_MACRO;

#ifdef __BIG_ENDIAN
        switch (cpp) {
        case 4:
                tiling_flags |= RADEON_TILING_SWAP_32BIT;
                break;
        case 2:
                tiling_flags |= RADEON_TILING_SWAP_16BIT;
                break;
        default:
                break;
        }
#endif

        if (tiling_flags) {
                ret = radeon_bo_set_tiling_flags(rbo,
                                                 tiling_flags | RADEON_TILING_SURFACE,
                                                 mode_cmd->pitches[0]);
                if (ret)
                        dev_err(rdev->dev, "FB failed to set tiling flags\n");
        }

        ret = radeon_bo_reserve(rbo, false);
        if (unlikely(ret != 0))
                goto err_radeon_fbdev_destroy_pinned_object;
        /* Only 27 bit offset for legacy CRTC */
        ret = radeon_bo_pin_restricted(rbo, RADEON_GEM_DOMAIN_VRAM,
                                       ASIC_IS_AVIVO(rdev) ? 0 : 1 << 27,
                                       NULL);
        if (ret) {
                radeon_bo_unreserve(rbo);
                goto err_radeon_fbdev_destroy_pinned_object;
        }
        if (fb_tiled)
                radeon_bo_check_tiling(rbo, 0, 0);
        ret = radeon_bo_kmap(rbo, NULL);
        radeon_bo_unreserve(rbo);
        if (ret)
                goto err_radeon_fbdev_destroy_pinned_object;

        *gobj_p = gobj;
        return 0;

err_radeon_fbdev_destroy_pinned_object:
        radeon_fbdev_destroy_pinned_object(gobj);
        *gobj_p = NULL;
        return ret;
}

/*
 * Fbdev ops and struct fb_ops
 */

static int radeon_fbdev_fb_open(struct fb_info *info, int user)
{
        struct drm_fb_helper *fb_helper = info->par;
        struct radeon_device *rdev = fb_helper->dev->dev_private;
        int ret;

        ret = pm_runtime_get_sync(rdev_to_drm(rdev)->dev);
        if (ret < 0 && ret != -EACCES)
                goto err_pm_runtime_mark_last_busy;

        return 0;

err_pm_runtime_mark_last_busy:
        pm_runtime_put_autosuspend(rdev_to_drm(rdev)->dev);
        return ret;
}

static int radeon_fbdev_fb_release(struct fb_info *info, int user)
{
        struct drm_fb_helper *fb_helper = info->par;
        struct radeon_device *rdev = fb_helper->dev->dev_private;

        pm_runtime_put_autosuspend(rdev_to_drm(rdev)->dev);

        return 0;
}

static void radeon_fbdev_fb_destroy(struct fb_info *info)
{
        struct drm_fb_helper *fb_helper = info->par;
        struct drm_framebuffer *fb = fb_helper->fb;
        struct drm_gem_object *gobj = drm_gem_fb_get_obj(fb, 0);

        drm_fb_helper_fini(fb_helper);

        drm_framebuffer_unregister_private(fb);
        drm_framebuffer_cleanup(fb);
        kfree(fb);
        radeon_fbdev_destroy_pinned_object(gobj);

        drm_client_release(&fb_helper->client);
}

static const struct fb_ops radeon_fbdev_fb_ops = {
        .owner = THIS_MODULE,
        .fb_open = radeon_fbdev_fb_open,
        .fb_release = radeon_fbdev_fb_release,
        FB_DEFAULT_IOMEM_OPS,
        DRM_FB_HELPER_DEFAULT_OPS,
        .fb_destroy = radeon_fbdev_fb_destroy,
};

static const struct drm_fb_helper_funcs radeon_fbdev_fb_helper_funcs = {
};

int radeon_fbdev_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
                                    struct drm_fb_helper_surface_size *sizes)
{
        struct radeon_device *rdev = fb_helper->dev->dev_private;
        const struct drm_format_info *format_info;
        struct drm_mode_fb_cmd2 mode_cmd = { };
        struct fb_info *info = fb_helper->info;
        struct drm_gem_object *gobj;
        struct radeon_bo *rbo;
        struct drm_framebuffer *fb;
        int ret;
        unsigned long tmp;

        mode_cmd.width = sizes->surface_width;
        mode_cmd.height = sizes->surface_height;

        /* avivo can't scanout real 24bpp */
        if ((sizes->surface_bpp == 24) && ASIC_IS_AVIVO(rdev))
                sizes->surface_bpp = 32;

        mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
                                                          sizes->surface_depth);

        format_info = drm_get_format_info(rdev_to_drm(rdev), mode_cmd.pixel_format,
                                          mode_cmd.modifier[0]);
        ret = radeon_fbdev_create_pinned_object(fb_helper, format_info, &mode_cmd, &gobj);
        if (ret) {
                DRM_ERROR("failed to create fbcon object %d\n", ret);
                return ret;
        }
        rbo = gem_to_radeon_bo(gobj);

        fb = kzalloc_obj(*fb);
        if (!fb) {
                ret = -ENOMEM;
                goto err_radeon_fbdev_destroy_pinned_object;
        }
        ret = radeon_framebuffer_init(rdev_to_drm(rdev), fb, format_info, &mode_cmd, gobj);
        if (ret) {
                DRM_ERROR("failed to initialize framebuffer %d\n", ret);
                goto err_kfree;
        }

        /* setup helper */
        fb_helper->funcs = &radeon_fbdev_fb_helper_funcs;
        fb_helper->fb = fb;

        info->fbops = &radeon_fbdev_fb_ops;

        /* radeon resume is fragile and needs a vt switch to help it along */
        info->skip_vt_switch = false;

        drm_fb_helper_fill_info(info, fb_helper, sizes);

        tmp = radeon_bo_gpu_offset(rbo) - rdev->mc.vram_start;
        info->fix.smem_start = rdev->mc.aper_base + tmp;
        info->fix.smem_len = radeon_bo_size(rbo);
        info->screen_base = (__force void __iomem *)rbo->kptr;
        info->screen_size = radeon_bo_size(rbo);

        memset_io(info->screen_base, 0, info->screen_size);

        /* Use default scratch pixmap (info->pixmap.flags = FB_PIXMAP_SYSTEM) */

        DRM_INFO("fb mappable at 0x%lX\n",  info->fix.smem_start);
        DRM_INFO("vram apper at 0x%lX\n",  (unsigned long)rdev->mc.aper_base);
        DRM_INFO("size %lu\n", (unsigned long)radeon_bo_size(rbo));
        DRM_INFO("fb depth is %d\n", fb->format->depth);
        DRM_INFO("   pitch is %d\n", fb->pitches[0]);

        return 0;

err_kfree:
        kfree(fb);
err_radeon_fbdev_destroy_pinned_object:
        radeon_fbdev_destroy_pinned_object(gobj);
        return ret;
}

bool radeon_fbdev_robj_is_fb(struct radeon_device *rdev, struct radeon_bo *robj)
{
        struct drm_fb_helper *fb_helper = rdev_to_drm(rdev)->fb_helper;
        struct drm_gem_object *gobj;

        if (!fb_helper)
                return false;

        gobj = drm_gem_fb_get_obj(fb_helper->fb, 0);
        if (!gobj)
                return false;
        if (gobj != &robj->tbo.base)
                return false;

        return true;
}