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