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_SYS_OPS_RDWR,
  63         DRM_FB_HELPER_DEFAULT_OPS,
  64         __FB_DEFAULT_SYS_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->screen_base = (void __iomem *)bo->vaddr + offset;
 136         info->screen_size = size;
 137         info->fix.smem_start = (unsigned long)(bo->iova + offset);
 138         info->fix.smem_len = size;
 139
 140         return 0;
 141
 142 destroy:
 143         drm_framebuffer_remove(fb);
 144         return err;
 145 }
 146
 147 static const struct drm_fb_helper_funcs tegra_fb_helper_funcs = {
 148         .fb_probe = tegra_fbdev_probe,
 149 };
 150
 151 /*
 152  * struct drm_client
 153  */
 154
 155 static void tegra_fbdev_client_unregister(struct drm_client_dev *client)
 156 {
 157         struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
 158
 159         if (fb_helper->info) {
 160                 drm_fb_helper_unregister_info(fb_helper);
 161         } else {
 162                 drm_client_release(&fb_helper->client);
 163                 drm_fb_helper_unprepare(fb_helper);
 164                 kfree(fb_helper);
 165         }
 166 }
 167
 168 static int tegra_fbdev_client_restore(struct drm_client_dev *client)
 169 {
 170         drm_fb_helper_lastclose(client->dev);
 171
 172         return 0;
 173 }
 174
 175 static int tegra_fbdev_client_hotplug(struct drm_client_dev *client)
 176 {
 177         struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
 178         struct drm_device *dev = client->dev;
 179         int ret;
 180
 181         if (dev->fb_helper)
 182                 return drm_fb_helper_hotplug_event(dev->fb_helper);
 183
 184         ret = drm_fb_helper_init(dev, fb_helper);
 185         if (ret)
 186                 goto err_drm_err;
 187
 188         if (!drm_drv_uses_atomic_modeset(dev))
 189                 drm_helper_disable_unused_functions(dev);
 190
 191         ret = drm_fb_helper_initial_config(fb_helper);
 192         if (ret)
 193                 goto err_drm_fb_helper_fini;
 194
 195         return 0;
 196
 197 err_drm_fb_helper_fini:
 198         drm_fb_helper_fini(fb_helper);
 199 err_drm_err:
 200         drm_err(dev, "Failed to setup fbdev emulation (ret=%d)\n", ret);
 201         return ret;
 202 }
 203
 204 static const struct drm_client_funcs tegra_fbdev_client_funcs = {
 205         .owner          = THIS_MODULE,
 206         .unregister     = tegra_fbdev_client_unregister,
 207         .restore        = tegra_fbdev_client_restore,
 208         .hotplug        = tegra_fbdev_client_hotplug,
 209 };
 210
 211 void tegra_fbdev_setup(struct drm_device *dev)
 212 {
 213         struct drm_fb_helper *helper;
 214         int ret;
 215
 216         drm_WARN(dev, !dev->registered, "Device has not been registered.\n");
 217         drm_WARN(dev, dev->fb_helper, "fb_helper is already set!\n");
 218
 219         helper = kzalloc(sizeof(*helper), GFP_KERNEL);
 220         if (!helper)
 221                 return;
 222         drm_fb_helper_prepare(dev, helper, 32, &tegra_fb_helper_funcs);
 223
 224         ret = drm_client_init(dev, &helper->client, "fbdev", &tegra_fbdev_client_funcs);
 225         if (ret)
 226                 goto err_drm_client_init;
 227
 228         ret = tegra_fbdev_client_hotplug(&helper->client);
 229         if (ret)
 230                 drm_dbg_kms(dev, "client hotplug ret=%d\n", ret);
 231
 232         drm_client_register(&helper->client);
 233
 234         return;
 235
 236 err_drm_client_init:
 237         drm_fb_helper_unprepare(helper);
 238         kfree(helper);
 239 }