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_plane_helper.h>
  15 #include <drm/drmP.h>
  16
  17 #include "sun4i_backend.h"
  18 #include "sun4i_layer.h"
  19 #include "sunxi_engine.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 void sun4i_backend_layer_atomic_disable(struct drm_plane *plane,
  29                                                struct drm_plane_state *old_state)
  30 {
  31         struct sun4i_layer *layer = plane_to_sun4i_layer(plane);
  32         struct sun4i_backend *backend = layer->backend;
  33
  34         sun4i_backend_layer_enable(backend, layer->id, false);
  35 }
  36
  37 static void sun4i_backend_layer_atomic_update(struct drm_plane *plane,
  38                                               struct drm_plane_state *old_state)
  39 {
  40         struct sun4i_layer *layer = plane_to_sun4i_layer(plane);
  41         struct sun4i_backend *backend = layer->backend;
  42
  43         sun4i_backend_update_layer_coord(backend, layer->id, plane);
  44         sun4i_backend_update_layer_formats(backend, layer->id, plane);
  45         sun4i_backend_update_layer_buffer(backend, layer->id, plane);
  46         sun4i_backend_layer_enable(backend, layer->id, true);
  47 }
  48
  49 static const struct drm_plane_helper_funcs sun4i_backend_layer_helper_funcs = {
  50         .atomic_disable = sun4i_backend_layer_atomic_disable,
  51         .atomic_update  = sun4i_backend_layer_atomic_update,
  52 };
  53
  54 static const struct drm_plane_funcs sun4i_backend_layer_funcs = {
  55         .atomic_destroy_state   = drm_atomic_helper_plane_destroy_state,
  56         .atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
  57         .destroy                = drm_plane_cleanup,
  58         .disable_plane          = drm_atomic_helper_disable_plane,
  59         .reset                  = drm_atomic_helper_plane_reset,
  60         .update_plane           = drm_atomic_helper_update_plane,
  61 };
  62
  63 static const uint32_t sun4i_backend_layer_formats_primary[] = {
  64         DRM_FORMAT_ARGB8888,
  65         DRM_FORMAT_RGB888,
  66         DRM_FORMAT_RGB565,
  67         DRM_FORMAT_XRGB8888,
  68 };
  69
  70 static const uint32_t sun4i_backend_layer_formats_overlay[] = {
  71         DRM_FORMAT_ARGB8888,
  72         DRM_FORMAT_ARGB4444,
  73         DRM_FORMAT_ARGB1555,
  74         DRM_FORMAT_RGBA5551,
  75         DRM_FORMAT_RGBA4444,
  76         DRM_FORMAT_RGB888,
  77         DRM_FORMAT_RGB565,
  78         DRM_FORMAT_XRGB8888,
  79 };
  80
  81 static const struct sun4i_plane_desc sun4i_backend_planes[] = {
  82         {
  83                 .type = DRM_PLANE_TYPE_PRIMARY,
  84                 .pipe = 0,
  85                 .formats = sun4i_backend_layer_formats_primary,
  86                 .nformats = ARRAY_SIZE(sun4i_backend_layer_formats_primary),
  87         },
  88         {
  89                 .type = DRM_PLANE_TYPE_OVERLAY,
  90                 .pipe = 1,
  91                 .formats = sun4i_backend_layer_formats_overlay,
  92                 .nformats = ARRAY_SIZE(sun4i_backend_layer_formats_overlay),
  93         },
  94 };
  95
  96 static struct sun4i_layer *sun4i_layer_init_one(struct drm_device *drm,
  97                                                 struct sun4i_backend *backend,
  98                                                 const struct sun4i_plane_desc *plane)
  99 {
 100         struct sun4i_layer *layer;
 101         int ret;
 102
 103         layer = devm_kzalloc(drm->dev, sizeof(*layer), GFP_KERNEL);
 104         if (!layer)
 105                 return ERR_PTR(-ENOMEM);
 106
 107         /* possible crtcs are set later */
 108         ret = drm_universal_plane_init(drm, &layer->plane, 0,
 109                                        &sun4i_backend_layer_funcs,
 110                                        plane->formats, plane->nformats,
 111                                        NULL, plane->type, NULL);
 112         if (ret) {
 113                 dev_err(drm->dev, "Couldn't initialize layer\n");
 114                 return ERR_PTR(ret);
 115         }
 116
 117         drm_plane_helper_add(&layer->plane,
 118                              &sun4i_backend_layer_helper_funcs);
 119         layer->backend = backend;
 120
 121         return layer;
 122 }
 123
 124 struct drm_plane **sun4i_layers_init(struct drm_device *drm,
 125                                      struct sunxi_engine *engine)
 126 {
 127         struct drm_plane **planes;
 128         struct sun4i_backend *backend = engine_to_sun4i_backend(engine);
 129         int i;
 130
 131         planes = devm_kcalloc(drm->dev, ARRAY_SIZE(sun4i_backend_planes) + 1,
 132                               sizeof(*planes), GFP_KERNEL);
 133         if (!planes)
 134                 return ERR_PTR(-ENOMEM);
 135
 136         /*
 137          * The hardware is a bit unusual here.
 138          *
 139          * Even though it supports 4 layers, it does the composition
 140          * in two separate steps.
 141          *
 142          * The first one is assigning a layer to one of its two
 143          * pipes. If more that 1 layer is assigned to the same pipe,
 144          * and if pixels overlaps, the pipe will take the pixel from
 145          * the layer with the highest priority.
 146          *
 147          * The second step is the actual alpha blending, that takes
 148          * the two pipes as input, and uses the eventual alpha
 149          * component to do the transparency between the two.
 150          *
 151          * This two steps scenario makes us unable to guarantee a
 152          * robust alpha blending between the 4 layers in all
 153          * situations. So we just expose two layers, one per pipe. On
 154          * SoCs that support it, sprites could fill the need for more
 155          * layers.
 156          */
 157         for (i = 0; i < ARRAY_SIZE(sun4i_backend_planes); i++) {
 158                 const struct sun4i_plane_desc *plane = &sun4i_backend_planes[i];
 159                 struct sun4i_layer *layer;
 160
 161                 layer = sun4i_layer_init_one(drm, backend, plane);
 162                 if (IS_ERR(layer)) {
 163                         dev_err(drm->dev, "Couldn't initialize %s plane\n",
 164                                 i ? "overlay" : "primary");
 165                         return ERR_CAST(layer);
 166                 };
 167
 168                 DRM_DEBUG_DRIVER("Assigning %s plane to pipe %d\n",
 169                                  i ? "overlay" : "primary", plane->pipe);
 170                 regmap_update_bits(engine->regs, SUN4I_BACKEND_ATTCTL_REG0(i),
 171                                    SUN4I_BACKEND_ATTCTL_REG0_LAY_PIPESEL_MASK,
 172                                    SUN4I_BACKEND_ATTCTL_REG0_LAY_PIPESEL(plane->pipe));
 173
 174                 layer->id = i;
 175                 planes[i] = &layer->plane;
 176         };
 177
 178         return planes;
 179 }