drivers/gpu/drm/sun4i/sun4i_layer.c

   1 /*
   2  * Copyright (C) 2015 Free Electrons
   3  * Copyright (C) 2015 NextThing Co
   4  *
   5  * Maxime Ripard <maxime.ripard@free-electrons.com>
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License as
   9  * published by the Free Software Foundation; either version 2 of
  10  * the License, or (at your option) any later version.
  11  */
  12
  13 #include <drm/drm_atomic_helper.h>
  14 #include <drm/drm_crtc.h>
  15 #include <drm/drm_plane_helper.h>
  16 #include <drm/drmP.h>
  17
  18 #include "sun4i_backend.h"
  19 #include "sun4i_drv.h"
  20 #include "sun4i_layer.h"
  21
  22 struct sun4i_plane_desc {
  23                enum drm_plane_type     type;
  24                u8                      pipe;
  25                const uint32_t          *formats;
  26                uint32_t                nformats;
  27 };
  28
  29 static int sun4i_backend_layer_atomic_check(struct drm_plane *plane,
  30                                             struct drm_plane_state *state)
  31 {
  32         return 0;
  33 }
  34
  35 static void sun4i_backend_layer_atomic_disable(struct drm_plane *plane,
  36                                                struct drm_plane_state *old_state)
  37 {
  38         struct sun4i_layer *layer = plane_to_sun4i_layer(plane);
  39         struct sun4i_drv *drv = layer->drv;
  40         struct sun4i_backend *backend = drv->backend;
  41
  42         sun4i_backend_layer_enable(backend, layer->id, false);
  43 }
  44
  45 static void sun4i_backend_layer_atomic_update(struct drm_plane *plane,
  46                                               struct drm_plane_state *old_state)
  47 {
  48         struct sun4i_layer *layer = plane_to_sun4i_layer(plane);
  49         struct sun4i_drv *drv = layer->drv;
  50         struct sun4i_backend *backend = drv->backend;
  51
  52         sun4i_backend_update_layer_coord(backend, layer->id, plane);
  53         sun4i_backend_update_layer_formats(backend, layer->id, plane);
  54         sun4i_backend_update_layer_buffer(backend, layer->id, plane);
  55         sun4i_backend_layer_enable(backend, layer->id, true);
  56 }
  57
  58 static struct drm_plane_helper_funcs sun4i_backend_layer_helper_funcs = {
  59         .atomic_check   = sun4i_backend_layer_atomic_check,
  60         .atomic_disable = sun4i_backend_layer_atomic_disable,
  61         .atomic_update  = sun4i_backend_layer_atomic_update,
  62 };
  63
  64 static const struct drm_plane_funcs sun4i_backend_layer_funcs = {
  65         .atomic_destroy_state   = drm_atomic_helper_plane_destroy_state,
  66         .atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
  67         .destroy                = drm_plane_cleanup,
  68         .disable_plane          = drm_atomic_helper_disable_plane,
  69         .reset                  = drm_atomic_helper_plane_reset,
  70         .update_plane           = drm_atomic_helper_update_plane,
  71 };
  72
  73 static const uint32_t sun4i_backend_layer_formats_primary[] = {
  74         DRM_FORMAT_ARGB8888,
  75         DRM_FORMAT_RGB888,
  76         DRM_FORMAT_RGB565,
  77         DRM_FORMAT_XRGB8888,
  78 };
  79
  80 static const uint32_t sun4i_backend_layer_formats_overlay[] = {
  81         DRM_FORMAT_ARGB8888,
  82         DRM_FORMAT_ARGB4444,
  83         DRM_FORMAT_ARGB1555,
  84         DRM_FORMAT_RGBA5551,
  85         DRM_FORMAT_RGBA4444,
  86         DRM_FORMAT_RGB888,
  87         DRM_FORMAT_RGB565,
  88         DRM_FORMAT_XRGB8888,
  89 };
  90
  91 static const struct sun4i_plane_desc sun4i_backend_planes[] = {
  92         {
  93                 .type = DRM_PLANE_TYPE_PRIMARY,
  94                 .pipe = 0,
  95                 .formats = sun4i_backend_layer_formats_primary,
  96                 .nformats = ARRAY_SIZE(sun4i_backend_layer_formats_primary),
  97         },
  98         {
  99                 .type = DRM_PLANE_TYPE_OVERLAY,
 100                 .pipe = 1,
 101                 .formats = sun4i_backend_layer_formats_overlay,
 102                 .nformats = ARRAY_SIZE(sun4i_backend_layer_formats_overlay),
 103         },
 104 };
 105
 106 static struct sun4i_layer *sun4i_layer_init_one(struct drm_device *drm,
 107                                                 const struct sun4i_plane_desc *plane)
 108 {
 109         struct sun4i_drv *drv = drm->dev_private;
 110         struct sun4i_layer *layer;
 111         int ret;
 112
 113         layer = devm_kzalloc(drm->dev, sizeof(*layer), GFP_KERNEL);
 114         if (!layer)
 115                 return ERR_PTR(-ENOMEM);
 116
 117         ret = drm_universal_plane_init(drm, &layer->plane, BIT(0),
 118                                        &sun4i_backend_layer_funcs,
 119                                        plane->formats, plane->nformats,
 120                                        plane->type, NULL);
 121         if (ret) {
 122                 dev_err(drm->dev, "Couldn't initialize layer\n");
 123                 return ERR_PTR(ret);
 124         }
 125
 126         drm_plane_helper_add(&layer->plane,
 127                              &sun4i_backend_layer_helper_funcs);
 128         layer->drv = drv;
 129
 130         if (plane->type == DRM_PLANE_TYPE_PRIMARY)
 131                 drv->primary = &layer->plane;
 132
 133         return layer;
 134 }
 135
 136 struct sun4i_layer **sun4i_layers_init(struct drm_device *drm)
 137 {
 138         struct sun4i_drv *drv = drm->dev_private;
 139         struct sun4i_layer **layers;
 140         int i;
 141
 142         layers = devm_kcalloc(drm->dev, ARRAY_SIZE(sun4i_backend_planes),
 143                               sizeof(**layers), GFP_KERNEL);
 144         if (!layers)
 145                 return ERR_PTR(-ENOMEM);
 146
 147         /*
 148          * The hardware is a bit unusual here.
 149          *
 150          * Even though it supports 4 layers, it does the composition
 151          * in two separate steps.
 152          *
 153          * The first one is assigning a layer to one of its two
 154          * pipes. If more that 1 layer is assigned to the same pipe,
 155          * and if pixels overlaps, the pipe will take the pixel from
 156          * the layer with the highest priority.
 157          *
 158          * The second step is the actual alpha blending, that takes
 159          * the two pipes as input, and uses the eventual alpha
 160          * component to do the transparency between the two.
 161          *
 162          * This two steps scenario makes us unable to guarantee a
 163          * robust alpha blending between the 4 layers in all
 164          * situations. So we just expose two layers, one per pipe. On
 165          * SoCs that support it, sprites could fill the need for more
 166          * layers.
 167          */
 168         for (i = 0; i < ARRAY_SIZE(sun4i_backend_planes); i++) {
 169                 const struct sun4i_plane_desc *plane = &sun4i_backend_planes[i];
 170                 struct sun4i_layer *layer = layers[i];
 171
 172                 layer = sun4i_layer_init_one(drm, plane);
 173                 if (IS_ERR(layer)) {
 174                         dev_err(drm->dev, "Couldn't initialize %s plane\n",
 175                                 i ? "overlay" : "primary");
 176                         return ERR_CAST(layer);
 177                 };
 178
 179                 DRM_DEBUG_DRIVER("Assigning %s plane to pipe %d\n",
 180                                  i ? "overlay" : "primary", plane->pipe);
 181                 regmap_update_bits(drv->backend->regs, SUN4I_BACKEND_ATTCTL_REG0(i),
 182                                    SUN4I_BACKEND_ATTCTL_REG0_LAY_PIPESEL_MASK,
 183                                    SUN4I_BACKEND_ATTCTL_REG0_LAY_PIPESEL(plane->pipe));
 184
 185                 layer->id = i;
 186         };
 187
 188         return layers;
 189 }