drivers/gpu/drm/msm/msm_fbdev.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2013 Red Hat
   4  * Author: Rob Clark <[email protected]>
   5  */
   6
   7 #include <linux/fb.h>
   8
   9 #include <drm/drm_drv.h>
  10 #include <drm/drm_crtc_helper.h>
  11 #include <drm/drm_fb_helper.h>
  12 #include <drm/drm_fourcc.h>
  13 #include <drm/drm_framebuffer.h>
  14 #include <drm/drm_prime.h>
  15
  16 #include "msm_drv.h"
  17 #include "msm_gem.h"
  18 #include "msm_kms.h"
  19
  20 static bool fbdev = true;
  21 MODULE_PARM_DESC(fbdev, "Enable fbdev compat layer");
  22 module_param(fbdev, bool, 0600);
  23
  24 /*
  25  * fbdev funcs, to implement legacy fbdev interface on top of drm driver
  26  */
  27
  28 FB_GEN_DEFAULT_DEFERRED_SYSMEM_OPS(msm_fbdev,
  29                                    drm_fb_helper_damage_range,
  30                                    drm_fb_helper_damage_area)
  31
  32 static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma)
  33 {
  34         struct drm_fb_helper *helper = (struct drm_fb_helper *)info->par;
  35         struct drm_gem_object *bo = msm_framebuffer_bo(helper->fb, 0);
  36
  37         return drm_gem_prime_mmap(bo, vma);
  38 }
  39
  40 static void msm_fbdev_fb_destroy(struct fb_info *info)
  41 {
  42         struct drm_fb_helper *helper = (struct drm_fb_helper *)info->par;
  43         struct drm_framebuffer *fb = helper->fb;
  44         struct drm_gem_object *bo = msm_framebuffer_bo(fb, 0);
  45
  46         DBG();
  47
  48         drm_fb_helper_fini(helper);
  49
  50         /* this will free the backing object */
  51         msm_gem_put_vaddr(bo);
  52         drm_framebuffer_remove(fb);
  53
  54         drm_client_release(&helper->client);
  55         drm_fb_helper_unprepare(helper);
  56         kfree(helper);
  57 }
  58
  59 static const struct fb_ops msm_fb_ops = {
  60         .owner = THIS_MODULE,
  61         __FB_DEFAULT_DEFERRED_OPS_RDWR(msm_fbdev),
  62         DRM_FB_HELPER_DEFAULT_OPS,
  63         __FB_DEFAULT_DEFERRED_OPS_DRAW(msm_fbdev),
  64         .fb_mmap = msm_fbdev_mmap,
  65         .fb_destroy = msm_fbdev_fb_destroy,
  66 };
  67
  68 static int msm_fbdev_create(struct drm_fb_helper *helper,
  69                 struct drm_fb_helper_surface_size *sizes)
  70 {
  71         struct drm_device *dev = helper->dev;
  72         struct msm_drm_private *priv = dev->dev_private;
  73         struct drm_framebuffer *fb = NULL;
  74         struct drm_gem_object *bo;
  75         struct fb_info *fbi = NULL;
  76         uint64_t paddr;
  77         uint32_t format;
  78         int ret, pitch;
  79
  80         format = drm_mode_legacy_fb_format(sizes->surface_bpp, sizes->surface_depth);
  81
  82         DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
  83                         sizes->surface_height, sizes->surface_bpp,
  84                         sizes->fb_width, sizes->fb_height);
  85
  86         pitch = align_pitch(sizes->surface_width, sizes->surface_bpp);
  87         fb = msm_alloc_stolen_fb(dev, sizes->surface_width,
  88                         sizes->surface_height, pitch, format);
  89
  90         if (IS_ERR(fb)) {
  91                 DRM_DEV_ERROR(dev->dev, "failed to allocate fb\n");
  92                 return PTR_ERR(fb);
  93         }
  94
  95         bo = msm_framebuffer_bo(fb, 0);
  96
  97         /*
  98          * NOTE: if we can be guaranteed to be able to map buffer
  99          * in panic (ie. lock-safe, etc) we could avoid pinning the
 100          * buffer now:
 101          */
 102         ret = msm_gem_get_and_pin_iova(bo, priv->kms->aspace, &paddr);
 103         if (ret) {
 104                 DRM_DEV_ERROR(dev->dev, "failed to get buffer obj iova: %d\n", ret);
 105                 goto fail;
 106         }
 107
 108         fbi = drm_fb_helper_alloc_info(helper);
 109         if (IS_ERR(fbi)) {
 110                 DRM_DEV_ERROR(dev->dev, "failed to allocate fb info\n");
 111                 ret = PTR_ERR(fbi);
 112                 goto fail;
 113         }
 114
 115         DBG("fbi=%p, dev=%p", fbi, dev);
 116
 117         helper->fb = fb;
 118
 119         fbi->fbops = &msm_fb_ops;
 120
 121         drm_fb_helper_fill_info(fbi, helper, sizes);
 122
 123         fbi->screen_buffer = msm_gem_get_vaddr(bo);
 124         if (IS_ERR(fbi->screen_buffer)) {
 125                 ret = PTR_ERR(fbi->screen_buffer);
 126                 goto fail;
 127         }
 128         fbi->screen_size = bo->size;
 129         fbi->fix.smem_start = paddr;
 130         fbi->fix.smem_len = bo->size;
 131
 132         DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
 133         DBG("allocated %dx%d fb", fb->width, fb->height);
 134
 135         return 0;
 136
 137 fail:
 138         drm_framebuffer_remove(fb);
 139         return ret;
 140 }
 141
 142 static int msm_fbdev_fb_dirty(struct drm_fb_helper *helper,
 143                               struct drm_clip_rect *clip)
 144 {
 145         struct drm_device *dev = helper->dev;
 146         int ret;
 147
 148         /* Call damage handlers only if necessary */
 149         if (!(clip->x1 < clip->x2 && clip->y1 < clip->y2))
 150                 return 0;
 151
 152         if (helper->fb->funcs->dirty) {
 153                 ret = helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, clip, 1);
 154                 if (drm_WARN_ONCE(dev, ret, "Dirty helper failed: ret=%d\n", ret))
 155                         return ret;
 156         }
 157
 158         return 0;
 159 }
 160
 161 static const struct drm_fb_helper_funcs msm_fb_helper_funcs = {
 162         .fb_probe = msm_fbdev_create,
 163         .fb_dirty = msm_fbdev_fb_dirty,
 164 };
 165
 166 /*
 167  * struct drm_client
 168  */
 169
 170 static void msm_fbdev_client_unregister(struct drm_client_dev *client)
 171 {
 172         struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
 173
 174         if (fb_helper->info) {
 175                 drm_fb_helper_unregister_info(fb_helper);
 176         } else {
 177                 drm_client_release(&fb_helper->client);
 178                 drm_fb_helper_unprepare(fb_helper);
 179                 kfree(fb_helper);
 180         }
 181 }
 182
 183 static int msm_fbdev_client_restore(struct drm_client_dev *client)
 184 {
 185         drm_fb_helper_lastclose(client->dev);
 186
 187         return 0;
 188 }
 189
 190 static int msm_fbdev_client_hotplug(struct drm_client_dev *client)
 191 {
 192         struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
 193         struct drm_device *dev = client->dev;
 194         int ret;
 195
 196         if (dev->fb_helper)
 197                 return drm_fb_helper_hotplug_event(dev->fb_helper);
 198
 199         ret = drm_fb_helper_init(dev, fb_helper);
 200         if (ret)
 201                 goto err_drm_err;
 202
 203         if (!drm_drv_uses_atomic_modeset(dev))
 204                 drm_helper_disable_unused_functions(dev);
 205
 206         ret = drm_fb_helper_initial_config(fb_helper);
 207         if (ret)
 208                 goto err_drm_fb_helper_fini;
 209
 210         return 0;
 211
 212 err_drm_fb_helper_fini:
 213         drm_fb_helper_fini(fb_helper);
 214 err_drm_err:
 215         drm_err(dev, "Failed to setup fbdev emulation (ret=%d)\n", ret);
 216         return ret;
 217 }
 218
 219 static const struct drm_client_funcs msm_fbdev_client_funcs = {
 220         .owner          = THIS_MODULE,
 221         .unregister     = msm_fbdev_client_unregister,
 222         .restore        = msm_fbdev_client_restore,
 223         .hotplug        = msm_fbdev_client_hotplug,
 224 };
 225
 226 /* initialize fbdev helper */
 227 void msm_fbdev_setup(struct drm_device *dev)
 228 {
 229         struct drm_fb_helper *helper;
 230         int ret;
 231
 232         if (!fbdev)
 233                 return;
 234
 235         drm_WARN(dev, !dev->registered, "Device has not been registered.\n");
 236         drm_WARN(dev, dev->fb_helper, "fb_helper is already set!\n");
 237
 238         helper = kzalloc(sizeof(*helper), GFP_KERNEL);
 239         if (!helper)
 240                 return;
 241         drm_fb_helper_prepare(dev, helper, 32, &msm_fb_helper_funcs);
 242
 243         ret = drm_client_init(dev, &helper->client, "fbdev", &msm_fbdev_client_funcs);
 244         if (ret) {
 245                 drm_err(dev, "Failed to register client: %d\n", ret);
 246                 goto err_drm_fb_helper_unprepare;
 247         }
 248
 249         drm_client_register(&helper->client);
 250
 251         return;
 252
 253 err_drm_fb_helper_unprepare:
 254         drm_fb_helper_unprepare(helper);
 255         kfree(helper);
 256 }