/*
 * 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/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/tty.h>
#include <linux/sysrq.h>
#include <linux/delay.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/screen_info.h>
#include <linux/vga_switcheroo.h>
#include <linux/console.h>

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

#include "nouveau_drm.h"
#include "nouveau_gem.h"
#include "nouveau_bo.h"
#include "nouveau_fbcon.h"
#include "nouveau_chan.h"

#include "nouveau_crtc.h"

#include <core/client.h>
#include <core/device.h>

#include <subdev/fb.h>

MODULE_PARM_DESC(nofbaccel, "Disable fbcon acceleration");
static int nouveau_nofbaccel = 0;
module_param_named(nofbaccel, nouveau_nofbaccel, int, 0400);

static void
nouveau_fbcon_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
{
        struct nouveau_fbdev *fbcon = info->par;
        struct nouveau_drm *drm = nouveau_drm(fbcon->dev);
        struct nouveau_device *device = nv_device(drm->device);
        int ret;

        if (info->state != FBINFO_STATE_RUNNING)
                return;

        ret = -ENODEV;
        if (!in_interrupt() && !(info->flags & FBINFO_HWACCEL_DISABLED) &&
            mutex_trylock(&drm->client.mutex)) {
                if (device->card_type < NV_50)
                        ret = nv04_fbcon_fillrect(info, rect);
                else
                if (device->card_type < NV_C0)
                        ret = nv50_fbcon_fillrect(info, rect);
                else
                        ret = nvc0_fbcon_fillrect(info, rect);
                mutex_unlock(&drm->client.mutex);
        }

        if (ret == 0)
                return;

        if (ret != -ENODEV)
                nouveau_fbcon_gpu_lockup(info);
        cfb_fillrect(info, rect);
}

static void
nouveau_fbcon_copyarea(struct fb_info *info, const struct fb_copyarea *image)
{
        struct nouveau_fbdev *fbcon = info->par;
        struct nouveau_drm *drm = nouveau_drm(fbcon->dev);
        struct nouveau_device *device = nv_device(drm->device);
        int ret;

        if (info->state != FBINFO_STATE_RUNNING)
                return;

        ret = -ENODEV;
        if (!in_interrupt() && !(info->flags & FBINFO_HWACCEL_DISABLED) &&
            mutex_trylock(&drm->client.mutex)) {
                if (device->card_type < NV_50)
                        ret = nv04_fbcon_copyarea(info, image);
                else
                if (device->card_type < NV_C0)
                        ret = nv50_fbcon_copyarea(info, image);
                else
                        ret = nvc0_fbcon_copyarea(info, image);
                mutex_unlock(&drm->client.mutex);
        }

        if (ret == 0)
                return;

        if (ret != -ENODEV)
                nouveau_fbcon_gpu_lockup(info);
        cfb_copyarea(info, image);
}

static void
nouveau_fbcon_imageblit(struct fb_info *info, const struct fb_image *image)
{
        struct nouveau_fbdev *fbcon = info->par;
        struct nouveau_drm *drm = nouveau_drm(fbcon->dev);
        struct nouveau_device *device = nv_device(drm->device);
        int ret;

        if (info->state != FBINFO_STATE_RUNNING)
                return;

        ret = -ENODEV;
        if (!in_interrupt() && !(info->flags & FBINFO_HWACCEL_DISABLED) &&
            mutex_trylock(&drm->client.mutex)) {
                if (device->card_type < NV_50)
                        ret = nv04_fbcon_imageblit(info, image);
                else
                if (device->card_type < NV_C0)
                        ret = nv50_fbcon_imageblit(info, image);
                else
                        ret = nvc0_fbcon_imageblit(info, image);
                mutex_unlock(&drm->client.mutex);
        }

        if (ret == 0)
                return;

        if (ret != -ENODEV)
                nouveau_fbcon_gpu_lockup(info);
        cfb_imageblit(info, image);
}

static int
nouveau_fbcon_sync(struct fb_info *info)
{
        struct nouveau_fbdev *fbcon = info->par;
        struct nouveau_drm *drm = nouveau_drm(fbcon->dev);
        struct nouveau_channel *chan = drm->channel;
        int ret;

        if (!chan || !chan->accel_done || in_interrupt() ||
            info->state != FBINFO_STATE_RUNNING ||
            info->flags & FBINFO_HWACCEL_DISABLED)
                return 0;

        if (!mutex_trylock(&drm->client.mutex))
                return 0;

        ret = nouveau_channel_idle(chan);
        mutex_unlock(&drm->client.mutex);
        if (ret) {
                nouveau_fbcon_gpu_lockup(info);
                return 0;
        }

        chan->accel_done = false;
        return 0;
}

static struct fb_ops nouveau_fbcon_ops = {
        .owner = THIS_MODULE,
        .fb_check_var = drm_fb_helper_check_var,
        .fb_set_par = drm_fb_helper_set_par,
        .fb_fillrect = nouveau_fbcon_fillrect,
        .fb_copyarea = nouveau_fbcon_copyarea,
        .fb_imageblit = nouveau_fbcon_imageblit,
        .fb_sync = nouveau_fbcon_sync,
        .fb_pan_display = drm_fb_helper_pan_display,
        .fb_blank = drm_fb_helper_blank,
        .fb_setcmap = drm_fb_helper_setcmap,
        .fb_debug_enter = drm_fb_helper_debug_enter,
        .fb_debug_leave = drm_fb_helper_debug_leave,
};

static struct fb_ops nouveau_fbcon_sw_ops = {
        .owner = THIS_MODULE,
        .fb_check_var = drm_fb_helper_check_var,
        .fb_set_par = drm_fb_helper_set_par,
        .fb_fillrect = cfb_fillrect,
        .fb_copyarea = cfb_copyarea,
        .fb_imageblit = cfb_imageblit,
        .fb_pan_display = drm_fb_helper_pan_display,
        .fb_blank = drm_fb_helper_blank,
        .fb_setcmap = drm_fb_helper_setcmap,
        .fb_debug_enter = drm_fb_helper_debug_enter,
        .fb_debug_leave = drm_fb_helper_debug_leave,
};

static void nouveau_fbcon_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
                                    u16 blue, int regno)
{
        struct nouveau_crtc *nv_crtc = nouveau_crtc(crtc);

        nv_crtc->lut.r[regno] = red;
        nv_crtc->lut.g[regno] = green;
        nv_crtc->lut.b[regno] = blue;
}

static void nouveau_fbcon_gamma_get(struct drm_crtc *crtc, u16 *red, u16 *green,
                                    u16 *blue, int regno)
{
        struct nouveau_crtc *nv_crtc = nouveau_crtc(crtc);

        *red = nv_crtc->lut.r[regno];
        *green = nv_crtc->lut.g[regno];
        *blue = nv_crtc->lut.b[regno];
}

static void
nouveau_fbcon_zfill(struct drm_device *dev, struct nouveau_fbdev *fbcon)
{
        struct fb_info *info = fbcon->helper.fbdev;
        struct fb_fillrect rect;

        /* Clear the entire fbcon.  The drm will program every connector
         * with it's preferred mode.  If the sizes differ, one display will
         * quite likely have garbage around the console.
         */
        rect.dx = rect.dy = 0;
        rect.width = info->var.xres_virtual;
        rect.height = info->var.yres_virtual;
        rect.color = 0;
        rect.rop = ROP_COPY;
        info->fbops->fb_fillrect(info, &rect);
}

static int
nouveau_fbcon_create(struct drm_fb_helper *helper,
                     struct drm_fb_helper_surface_size *sizes)
{
        struct nouveau_fbdev *fbcon = (struct nouveau_fbdev *)helper;
        struct drm_device *dev = fbcon->dev;
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nouveau_device *device = nv_device(drm->device);
        struct fb_info *info;
        struct drm_framebuffer *fb;
        struct nouveau_framebuffer *nouveau_fb;
        struct nouveau_channel *chan;
        struct nouveau_bo *nvbo;
        struct drm_mode_fb_cmd2 mode_cmd;
        struct pci_dev *pdev = dev->pdev;
        int size, ret;

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

        mode_cmd.pitches[0] = mode_cmd.width * (sizes->surface_bpp >> 3);
        mode_cmd.pitches[0] = roundup(mode_cmd.pitches[0], 256);

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

        size = mode_cmd.pitches[0] * mode_cmd.height;
        size = roundup(size, PAGE_SIZE);

        ret = nouveau_gem_new(dev, size, 0, NOUVEAU_GEM_DOMAIN_VRAM,
                              0, 0x0000, &nvbo);
        if (ret) {
                NV_ERROR(drm, "failed to allocate framebuffer\n");
                goto out;
        }

        ret = nouveau_bo_pin(nvbo, TTM_PL_FLAG_VRAM);
        if (ret) {
                NV_ERROR(drm, "failed to pin fb: %d\n", ret);
                goto out_unref;
        }

        ret = nouveau_bo_map(nvbo);
        if (ret) {
                NV_ERROR(drm, "failed to map fb: %d\n", ret);
                goto out_unpin;
        }

        chan = nouveau_nofbaccel ? NULL : drm->channel;
        if (chan && device->card_type >= NV_50) {
                ret = nouveau_bo_vma_add(nvbo, nv_client(chan->cli)->vm,
                                        &fbcon->nouveau_fb.vma);
                if (ret) {
                        NV_ERROR(drm, "failed to map fb into chan: %d\n", ret);
                        chan = NULL;
                }
        }

        mutex_lock(&dev->struct_mutex);

        info = framebuffer_alloc(0, &pdev->dev);
        if (!info) {
                ret = -ENOMEM;
                goto out_unlock;
        }

        ret = fb_alloc_cmap(&info->cmap, 256, 0);
        if (ret) {
                ret = -ENOMEM;
                framebuffer_release(info);
                goto out_unlock;
        }

        info->par = fbcon;

        nouveau_framebuffer_init(dev, &fbcon->nouveau_fb, &mode_cmd, nvbo);

        nouveau_fb = &fbcon->nouveau_fb;
        fb = &nouveau_fb->base;

        /* setup helper */
        fbcon->helper.fb = fb;
        fbcon->helper.fbdev = info;

        strcpy(info->fix.id, "nouveaufb");
        if (!chan)
                info->flags = FBINFO_DEFAULT | FBINFO_HWACCEL_DISABLED;
        else
                info->flags = FBINFO_DEFAULT | FBINFO_HWACCEL_COPYAREA |
                              FBINFO_HWACCEL_FILLRECT |
                              FBINFO_HWACCEL_IMAGEBLIT;
        info->flags |= FBINFO_CAN_FORCE_OUTPUT;
        info->fbops = &nouveau_fbcon_sw_ops;
        info->fix.smem_start = nvbo->bo.mem.bus.base +
                               nvbo->bo.mem.bus.offset;
        info->fix.smem_len = size;

        info->screen_base = nvbo_kmap_obj_iovirtual(nouveau_fb->nvbo);
        info->screen_size = size;

        drm_fb_helper_fill_fix(info, fb->pitches[0], fb->depth);
        drm_fb_helper_fill_var(info, &fbcon->helper, sizes->fb_width, sizes->fb_height);

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

        mutex_unlock(&dev->struct_mutex);

        if (chan) {
                ret = -ENODEV;
                if (device->card_type < NV_50)
                        ret = nv04_fbcon_accel_init(info);
                else
                if (device->card_type < NV_C0)
                        ret = nv50_fbcon_accel_init(info);
                else
                        ret = nvc0_fbcon_accel_init(info);

                if (ret == 0)
                        info->fbops = &nouveau_fbcon_ops;
        }

        nouveau_fbcon_zfill(dev, fbcon);

        /* To allow resizeing without swapping buffers */
        NV_INFO(drm, "allocated %dx%d fb: 0x%lx, bo %p\n",
                nouveau_fb->base.width, nouveau_fb->base.height,
                nvbo->bo.offset, nvbo);

        vga_switcheroo_client_fb_set(dev->pdev, info);
        return 0;

out_unlock:
        mutex_unlock(&dev->struct_mutex);
        if (chan)
                nouveau_bo_vma_del(nvbo, &fbcon->nouveau_fb.vma);
        nouveau_bo_unmap(nvbo);
out_unpin:
        nouveau_bo_unpin(nvbo);
out_unref:
        nouveau_bo_ref(NULL, &nvbo);
out:
        return ret;
}

void
nouveau_fbcon_output_poll_changed(struct drm_device *dev)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        if (drm->fbcon)
                drm_fb_helper_hotplug_event(&drm->fbcon->helper);
}

static int
nouveau_fbcon_destroy(struct drm_device *dev, struct nouveau_fbdev *fbcon)
{
        struct nouveau_framebuffer *nouveau_fb = &fbcon->nouveau_fb;
        struct fb_info *info;

        if (fbcon->helper.fbdev) {
                info = fbcon->helper.fbdev;
                unregister_framebuffer(info);
                if (info->cmap.len)
                        fb_dealloc_cmap(&info->cmap);
                framebuffer_release(info);
        }

        if (nouveau_fb->nvbo) {
                nouveau_bo_unmap(nouveau_fb->nvbo);
                nouveau_bo_vma_del(nouveau_fb->nvbo, &nouveau_fb->vma);
                nouveau_bo_unpin(nouveau_fb->nvbo);
                drm_gem_object_unreference_unlocked(nouveau_fb->nvbo->gem);
                nouveau_fb->nvbo = NULL;
        }
        drm_fb_helper_fini(&fbcon->helper);
        drm_framebuffer_unregister_private(&nouveau_fb->base);
        drm_framebuffer_cleanup(&nouveau_fb->base);
        return 0;
}

void nouveau_fbcon_gpu_lockup(struct fb_info *info)
{
        struct nouveau_fbdev *fbcon = info->par;
        struct nouveau_drm *drm = nouveau_drm(fbcon->dev);

        NV_ERROR(drm, "GPU lockup - switching to software fbcon\n");
        info->flags |= FBINFO_HWACCEL_DISABLED;
}

static struct drm_fb_helper_funcs nouveau_fbcon_helper_funcs = {
        .gamma_set = nouveau_fbcon_gamma_set,
        .gamma_get = nouveau_fbcon_gamma_get,
        .fb_probe = nouveau_fbcon_create,
};


int
nouveau_fbcon_init(struct drm_device *dev)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nouveau_fb *pfb = nouveau_fb(drm->device);
        struct nouveau_fbdev *fbcon;
        int preferred_bpp;
        int ret;

        if (!dev->mode_config.num_crtc)
                return 0;

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

        fbcon->dev = dev;
        drm->fbcon = fbcon;
        fbcon->helper.funcs = &nouveau_fbcon_helper_funcs;

        ret = drm_fb_helper_init(dev, &fbcon->helper,
                                 dev->mode_config.num_crtc, 4);
        if (ret) {
                kfree(fbcon);
                return ret;
        }

        drm_fb_helper_single_add_all_connectors(&fbcon->helper);

        if (pfb->ram->size <= 32 * 1024 * 1024)
                preferred_bpp = 8;
        else
        if (pfb->ram->size <= 64 * 1024 * 1024)
                preferred_bpp = 16;
        else
                preferred_bpp = 32;

        /* disable all the possible outputs/crtcs before entering KMS mode */
        drm_helper_disable_unused_functions(dev);

        drm_fb_helper_initial_config(&fbcon->helper, preferred_bpp);
        return 0;
}

void
nouveau_fbcon_fini(struct drm_device *dev)
{
        struct nouveau_drm *drm = nouveau_drm(dev);

        if (!drm->fbcon)
                return;

        nouveau_fbcon_destroy(dev, drm->fbcon);
        kfree(drm->fbcon);
        drm->fbcon = NULL;
}

void nouveau_fbcon_save_disable_accel(struct drm_device *dev)
{
        struct nouveau_drm *drm = nouveau_drm(dev);

        drm->fbcon->saved_flags = drm->fbcon->helper.fbdev->flags;
        drm->fbcon->helper.fbdev->flags |= FBINFO_HWACCEL_DISABLED;
}

void nouveau_fbcon_restore_accel(struct drm_device *dev)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        drm->fbcon->helper.fbdev->flags = drm->fbcon->saved_flags;
}

void nouveau_fbcon_set_suspend(struct drm_device *dev, int state)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        console_lock();
        if (state == 0)
                nouveau_fbcon_save_disable_accel(dev);
        fb_set_suspend(drm->fbcon->helper.fbdev, state);
        if (state == 1)
                nouveau_fbcon_restore_accel(dev);
        console_unlock();
}

void nouveau_fbcon_zfill_all(struct drm_device *dev)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        nouveau_fbcon_zfill(dev, drm->fbcon);
}