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 const struct drm_fb_helper_funcs tegra_fbdev_helper_funcs = {
  70 };
  71
  72 int tegra_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
  73                                    struct drm_fb_helper_surface_size *sizes)
  74 {
  75         struct tegra_drm *tegra = helper->dev->dev_private;
  76         struct drm_device *drm = helper->dev;
  77         struct drm_mode_fb_cmd2 cmd = { 0 };
  78         unsigned int bytes_per_pixel;
  79         struct drm_framebuffer *fb;
  80         unsigned long offset;
  81         struct fb_info *info;
  82         struct tegra_bo *bo;
  83         size_t size;
  84         int err;
  85
  86         bytes_per_pixel = DIV_ROUND_UP(sizes->surface_bpp, 8);
  87
  88         cmd.width = sizes->surface_width;
  89         cmd.height = sizes->surface_height;
  90         cmd.pitches[0] = round_up(sizes->surface_width * bytes_per_pixel,
  91                                   tegra->pitch_align);
  92
  93         cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
  94                                                      sizes->surface_depth);
  95
  96         size = cmd.pitches[0] * cmd.height;
  97
  98         bo = tegra_bo_create(drm, size, 0);
  99         if (IS_ERR(bo))
 100                 return PTR_ERR(bo);
 101
 102         info = drm_fb_helper_alloc_info(helper);
 103         if (IS_ERR(info)) {
 104                 dev_err(drm->dev, "failed to allocate framebuffer info\n");
 105                 drm_gem_object_put(&bo->gem);
 106                 return PTR_ERR(info);
 107         }
 108
 109         fb = tegra_fb_alloc(drm, &cmd, &bo, 1);
 110         if (IS_ERR(fb)) {
 111                 err = PTR_ERR(fb);
 112                 dev_err(drm->dev, "failed to allocate DRM framebuffer: %d\n",
 113                         err);
 114                 drm_gem_object_put(&bo->gem);
 115                 return PTR_ERR(fb);
 116         }
 117
 118         helper->funcs = &tegra_fbdev_helper_funcs;
 119         helper->fb = fb;
 120         helper->info = info;
 121
 122         info->fbops = &tegra_fb_ops;
 123
 124         drm_fb_helper_fill_info(info, helper, sizes);
 125
 126         offset = info->var.xoffset * bytes_per_pixel +
 127                  info->var.yoffset * fb->pitches[0];
 128
 129         if (bo->pages) {
 130                 bo->vaddr = vmap(bo->pages, bo->num_pages, VM_MAP,
 131                                  pgprot_writecombine(PAGE_KERNEL));
 132                 if (!bo->vaddr) {
 133                         dev_err(drm->dev, "failed to vmap() framebuffer\n");
 134                         err = -ENOMEM;
 135                         goto destroy;
 136                 }
 137         }
 138
 139         info->flags |= FBINFO_VIRTFB;
 140         info->screen_buffer = bo->vaddr + offset;
 141         info->screen_size = size;
 142         info->fix.smem_start = (unsigned long)(bo->iova + offset);
 143         info->fix.smem_len = size;
 144
 145         return 0;
 146
 147 destroy:
 148         drm_framebuffer_remove(fb);
 149         return err;
 150 }