drivers/gpu/drm/tegra/fbdev.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2012-2013 Avionic Design GmbH
   4  * Copyright (C) 2012 NVIDIA CORPORATION.  All rights reserved.
   5  *
   6  * Based on the KMS/FB DMA helpers
   7  *   Copyright (C) 2012 Analog Devices Inc.
   8  */
   9
  10 #include <linux/console.h>
  11 #include <linux/fb.h>
  12 #include <linux/vmalloc.h>
  13
  14 #include <drm/drm_drv.h>
  15 #include <drm/drm_crtc_helper.h>
  16 #include <drm/drm_fb_helper.h>
  17 #include <drm/drm_fourcc.h>
  18 #include <drm/drm_framebuffer.h>
  19 #include <drm/drm_gem_framebuffer_helper.h>
  20 #include <drm/drm_modeset_helper.h>
  21
  22 #include "drm.h"
  23 #include "gem.h"
  24
  25 static int tegra_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
  26 {
  27         struct drm_fb_helper *helper = info->par;
  28         struct tegra_bo *bo;
  29         int err;
  30
  31         bo = tegra_fb_get_plane(helper->fb, 0);
  32
  33         err = drm_gem_mmap_obj(&bo->gem, bo->gem.size, vma);
  34         if (err < 0)
  35                 return err;
  36
  37         return __tegra_gem_mmap(&bo->gem, vma);
  38 }
  39
  40 static void tegra_fbdev_fb_destroy(struct fb_info *info)
  41 {
  42         struct drm_fb_helper *helper = info->par;
  43         struct drm_framebuffer *fb = helper->fb;
  44         struct tegra_bo *bo = tegra_fb_get_plane(fb, 0);
  45
  46         drm_fb_helper_fini(helper);
  47
  48         /* Undo the special mapping we made in fbdev probe. */
  49         if (bo->pages) {
  50                 vunmap(bo->vaddr);
  51                 bo->vaddr = NULL;
  52         }
  53         drm_framebuffer_remove(fb);
  54
  55         drm_client_release(&helper->client);
  56         drm_fb_helper_unprepare(helper);
  57         kfree(helper);
  58 }
  59
  60 static const struct fb_ops tegra_fb_ops = {
  61         .owner = THIS_MODULE,
  62         __FB_DEFAULT_DMAMEM_OPS_RDWR,
  63         DRM_FB_HELPER_DEFAULT_OPS,
  64         __FB_DEFAULT_DMAMEM_OPS_DRAW,
  65         .fb_mmap = tegra_fb_mmap,
  66         .fb_destroy = tegra_fbdev_fb_destroy,
  67 };
  68
  69 static int tegra_fbdev_probe(struct drm_fb_helper *helper,
  70                              struct drm_fb_helper_surface_size *sizes)
  71 {
  72         struct tegra_drm *tegra = helper->dev->dev_private;
  73         struct drm_device *drm = helper->dev;
  74         struct drm_mode_fb_cmd2 cmd = { 0 };
  75         unsigned int bytes_per_pixel;
  76         struct drm_framebuffer *fb;
  77         unsigned long offset;
  78         struct fb_info *info;
  79         struct tegra_bo *bo;
  80         size_t size;
  81         int err;
  82
  83         bytes_per_pixel = DIV_ROUND_UP(sizes->surface_bpp, 8);
  84
  85         cmd.width = sizes->surface_width;
  86         cmd.height = sizes->surface_height;
  87         cmd.pitches[0] = round_up(sizes->surface_width * bytes_per_pixel,
  88                                   tegra->pitch_align);
  89
  90         cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
  91                                                      sizes->surface_depth);
  92
  93         size = cmd.pitches[0] * cmd.height;
  94
  95         bo = tegra_bo_create(drm, size, 0);
  96         if (IS_ERR(bo))
  97                 return PTR_ERR(bo);
  98
  99         info = drm_fb_helper_alloc_info(helper);
 100         if (IS_ERR(info)) {
 101                 dev_err(drm->dev, "failed to allocate framebuffer info\n");
 102                 drm_gem_object_put(&bo->gem);
 103                 return PTR_ERR(info);
 104         }
 105
 106         fb = tegra_fb_alloc(drm, &cmd, &bo, 1);
 107         if (IS_ERR(fb)) {
 108                 err = PTR_ERR(fb);
 109                 dev_err(drm->dev, "failed to allocate DRM framebuffer: %d\n",
 110                         err);
 111                 drm_gem_object_put(&bo->gem);
 112                 return PTR_ERR(fb);
 113         }
 114
 115         helper->fb = fb;
 116         helper->info = info;
 117
 118         info->fbops = &tegra_fb_ops;
 119
 120         drm_fb_helper_fill_info(info, helper, sizes);
 121
 122         offset = info->var.xoffset * bytes_per_pixel +
 123                  info->var.yoffset * fb->pitches[0];
 124
 125         if (bo->pages) {
 126                 bo->vaddr = vmap(bo->pages, bo->num_pages, VM_MAP,
 127                                  pgprot_writecombine(PAGE_KERNEL));
 128                 if (!bo->vaddr) {
 129                         dev_err(drm->dev, "failed to vmap() framebuffer\n");
 130                         err = -ENOMEM;
 131                         goto destroy;
 132                 }
 133         }
 134
 135         info->flags |= FBINFO_VIRTFB;
 136         info->screen_buffer = bo->vaddr + offset;
 137         info->screen_size = size;
 138         info->fix.smem_start = (unsigned long)(bo->iova + offset);
 139         info->fix.smem_len = size;
 140
 141         return 0;
 142
 143 destroy:
 144         drm_framebuffer_remove(fb);
 145         return err;
 146 }
 147
 148 static const struct drm_fb_helper_funcs tegra_fb_helper_funcs = {
 149         .fb_probe = tegra_fbdev_probe,
 150 };
 151
 152 /*
 153  * struct drm_client
 154  */
 155
 156 static void tegra_fbdev_client_unregister(struct drm_client_dev *client)
 157 {
 158         struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
 159
 160         if (fb_helper->info) {
 161                 drm_fb_helper_unregister_info(fb_helper);
 162         } else {
 163                 drm_client_release(&fb_helper->client);
 164                 drm_fb_helper_unprepare(fb_helper);
 165                 kfree(fb_helper);
 166         }
 167 }
 168
 169 static int tegra_fbdev_client_restore(struct drm_client_dev *client)
 170 {
 171         drm_fb_helper_lastclose(client->dev);
 172
 173         return 0;
 174 }
 175
 176 static int tegra_fbdev_client_hotplug(struct drm_client_dev *client)
 177 {
 178         struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
 179         struct drm_device *dev = client->dev;
 180         int ret;
 181
 182         if (dev->fb_helper)
 183                 return drm_fb_helper_hotplug_event(dev->fb_helper);
 184
 185         ret = drm_fb_helper_init(dev, fb_helper);
 186         if (ret)
 187                 goto err_drm_err;
 188
 189         if (!drm_drv_uses_atomic_modeset(dev))
 190                 drm_helper_disable_unused_functions(dev);
 191
 192         ret = drm_fb_helper_initial_config(fb_helper);
 193         if (ret)
 194                 goto err_drm_fb_helper_fini;
 195
 196         return 0;
 197
 198 err_drm_fb_helper_fini:
 199         drm_fb_helper_fini(fb_helper);
 200 err_drm_err:
 201         drm_err(dev, "Failed to setup fbdev emulation (ret=%d)\n", ret);
 202         return ret;
 203 }
 204
 205 static const struct drm_client_funcs tegra_fbdev_client_funcs = {
 206         .owner          = THIS_MODULE,
 207         .unregister     = tegra_fbdev_client_unregister,
 208         .restore        = tegra_fbdev_client_restore,
 209         .hotplug        = tegra_fbdev_client_hotplug,
 210 };
 211
 212 void tegra_fbdev_setup(struct drm_device *dev)
 213 {
 214         struct drm_fb_helper *helper;
 215         int ret;
 216
 217         drm_WARN(dev, !dev->registered, "Device has not been registered.\n");
 218         drm_WARN(dev, dev->fb_helper, "fb_helper is already set!\n");
 219
 220         helper = kzalloc(sizeof(*helper), GFP_KERNEL);
 221         if (!helper)
 222                 return;
 223         drm_fb_helper_prepare(dev, helper, 32, &tegra_fb_helper_funcs);
 224
 225         ret = drm_client_init(dev, &helper->client, "fbdev", &tegra_fbdev_client_funcs);
 226         if (ret)
 227                 goto err_drm_client_init;
 228
 229         drm_client_register(&helper->client);
 230
 231         return;
 232
 233 err_drm_client_init:
 234         drm_fb_helper_unprepare(helper);
 235         kfree(helper);
 236 }