kernel/drivers/gpu/drm/vc4/vc4_plane.c

   1 /*
   2  * Copyright (C) 2015 Broadcom
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8
   9 /**
  10  * DOC: VC4 plane module
  11  *
  12  * Each DRM plane is a layer of pixels being scanned out by the HVS.
  13  *
  14  * At atomic modeset check time, we compute the HVS display element
  15  * state that would be necessary for displaying the plane (giving us a
  16  * chance to figure out if a plane configuration is invalid), then at
  17  * atomic flush time the CRTC will ask us to write our element state
  18  * into the region of the HVS that it has allocated for us.
  19  */
  20
  21 #include "vc4_drv.h"
  22 #include "vc4_regs.h"
  23 #include "drm_atomic_helper.h"
  24 #include "drm_fb_cma_helper.h"
  25 #include "drm_plane_helper.h"
  26
  27 struct vc4_plane_state {
  28         struct drm_plane_state base;
  29         u32 *dlist;
  30         u32 dlist_size; /* Number of dwords in allocated for the display list */
  31         u32 dlist_count; /* Number of used dwords in the display list. */
  32 };
  33
  34 static inline struct vc4_plane_state *
  35 to_vc4_plane_state(struct drm_plane_state *state)
  36 {
  37         return (struct vc4_plane_state *)state;
  38 }
  39
  40 static const struct hvs_format {
  41         u32 drm; /* DRM_FORMAT_* */
  42         u32 hvs; /* HVS_FORMAT_* */
  43         u32 pixel_order;
  44         bool has_alpha;
  45 } hvs_formats[] = {
  46         {
  47                 .drm = DRM_FORMAT_XRGB8888, .hvs = HVS_PIXEL_FORMAT_RGBA8888,
  48                 .pixel_order = HVS_PIXEL_ORDER_ABGR, .has_alpha = false,
  49         },
  50         {
  51                 .drm = DRM_FORMAT_ARGB8888, .hvs = HVS_PIXEL_FORMAT_RGBA8888,
  52                 .pixel_order = HVS_PIXEL_ORDER_ABGR, .has_alpha = true,
  53         },
  54 };
  55
  56 static const struct hvs_format *vc4_get_hvs_format(u32 drm_format)
  57 {
  58         unsigned i;
  59
  60         for (i = 0; i < ARRAY_SIZE(hvs_formats); i++) {
  61                 if (hvs_formats[i].drm == drm_format)
  62                         return &hvs_formats[i];
  63         }
  64
  65         return NULL;
  66 }
  67
  68 static bool plane_enabled(struct drm_plane_state *state)
  69 {
  70         return state->fb && state->crtc;
  71 }
  72
  73 static struct drm_plane_state *vc4_plane_duplicate_state(struct drm_plane *plane)
  74 {
  75         struct vc4_plane_state *vc4_state;
  76
  77         if (WARN_ON(!plane->state))
  78                 return NULL;
  79
  80         vc4_state = kmemdup(plane->state, sizeof(*vc4_state), GFP_KERNEL);
  81         if (!vc4_state)
  82                 return NULL;
  83
  84         __drm_atomic_helper_plane_duplicate_state(plane, &vc4_state->base);
  85
  86         if (vc4_state->dlist) {
  87                 vc4_state->dlist = kmemdup(vc4_state->dlist,
  88                                            vc4_state->dlist_count * 4,
  89                                            GFP_KERNEL);
  90                 if (!vc4_state->dlist) {
  91                         kfree(vc4_state);
  92                         return NULL;
  93                 }
  94                 vc4_state->dlist_size = vc4_state->dlist_count;
  95         }
  96
  97         return &vc4_state->base;
  98 }
  99
 100 static void vc4_plane_destroy_state(struct drm_plane *plane,
 101                                     struct drm_plane_state *state)
 102 {
 103         struct vc4_plane_state *vc4_state = to_vc4_plane_state(state);
 104
 105         kfree(vc4_state->dlist);
 106         __drm_atomic_helper_plane_destroy_state(plane, &vc4_state->base);
 107         kfree(state);
 108 }
 109
 110 /* Called during init to allocate the plane's atomic state. */
 111 static void vc4_plane_reset(struct drm_plane *plane)
 112 {
 113         struct vc4_plane_state *vc4_state;
 114
 115         WARN_ON(plane->state);
 116
 117         vc4_state = kzalloc(sizeof(*vc4_state), GFP_KERNEL);
 118         if (!vc4_state)
 119                 return;
 120
 121         plane->state = &vc4_state->base;
 122         vc4_state->base.plane = plane;
 123 }
 124
 125 static void vc4_dlist_write(struct vc4_plane_state *vc4_state, u32 val)
 126 {
 127         if (vc4_state->dlist_count == vc4_state->dlist_size) {
 128                 u32 new_size = max(4u, vc4_state->dlist_count * 2);
 129                 u32 *new_dlist = kmalloc(new_size * 4, GFP_KERNEL);
 130
 131                 if (!new_dlist)
 132                         return;
 133                 memcpy(new_dlist, vc4_state->dlist, vc4_state->dlist_count * 4);
 134
 135                 kfree(vc4_state->dlist);
 136                 vc4_state->dlist = new_dlist;
 137                 vc4_state->dlist_size = new_size;
 138         }
 139
 140         vc4_state->dlist[vc4_state->dlist_count++] = val;
 141 }
 142
 143 /* Writes out a full display list for an active plane to the plane's
 144  * private dlist state.
 145  */
 146 static int vc4_plane_mode_set(struct drm_plane *plane,
 147                               struct drm_plane_state *state)
 148 {
 149         struct vc4_plane_state *vc4_state = to_vc4_plane_state(state);
 150         struct drm_framebuffer *fb = state->fb;
 151         struct drm_gem_cma_object *bo = drm_fb_cma_get_gem_obj(fb, 0);
 152         u32 ctl0_offset = vc4_state->dlist_count;
 153         const struct hvs_format *format = vc4_get_hvs_format(fb->pixel_format);
 154         uint32_t offset = fb->offsets[0];
 155         int crtc_x = state->crtc_x;
 156         int crtc_y = state->crtc_y;
 157         int crtc_w = state->crtc_w;
 158         int crtc_h = state->crtc_h;
 159
 160         if (state->crtc_w << 16 != state->src_w ||
 161             state->crtc_h << 16 != state->src_h) {
 162                 /* We don't support scaling yet, which involves
 163                  * allocating the LBM memory for scaling temporary
 164                  * storage, and putting filter kernels in the HVS
 165                  * context.
 166                  */
 167                 return -EINVAL;
 168         }
 169
 170         if (crtc_x < 0) {
 171                 offset += drm_format_plane_cpp(fb->pixel_format, 0) * -crtc_x;
 172                 crtc_w += crtc_x;
 173                 crtc_x = 0;
 174         }
 175
 176         if (crtc_y < 0) {
 177                 offset += fb->pitches[0] * -crtc_y;
 178                 crtc_h += crtc_y;
 179                 crtc_y = 0;
 180         }
 181
 182         vc4_dlist_write(vc4_state,
 183                         SCALER_CTL0_VALID |
 184                         (format->pixel_order << SCALER_CTL0_ORDER_SHIFT) |
 185                         (format->hvs << SCALER_CTL0_PIXEL_FORMAT_SHIFT) |
 186                         SCALER_CTL0_UNITY);
 187
 188         /* Position Word 0: Image Positions and Alpha Value */
 189         vc4_dlist_write(vc4_state,
 190                         VC4_SET_FIELD(0xff, SCALER_POS0_FIXED_ALPHA) |
 191                         VC4_SET_FIELD(crtc_x, SCALER_POS0_START_X) |
 192                         VC4_SET_FIELD(crtc_y, SCALER_POS0_START_Y));
 193
 194         /* Position Word 1: Scaled Image Dimensions.
 195          * Skipped due to SCALER_CTL0_UNITY scaling.
 196          */
 197
 198         /* Position Word 2: Source Image Size, Alpha Mode */
 199         vc4_dlist_write(vc4_state,
 200                         VC4_SET_FIELD(format->has_alpha ?
 201                                       SCALER_POS2_ALPHA_MODE_PIPELINE :
 202                                       SCALER_POS2_ALPHA_MODE_FIXED,
 203                                       SCALER_POS2_ALPHA_MODE) |
 204                         VC4_SET_FIELD(crtc_w, SCALER_POS2_WIDTH) |
 205                         VC4_SET_FIELD(crtc_h, SCALER_POS2_HEIGHT));
 206
 207         /* Position Word 3: Context.  Written by the HVS. */
 208         vc4_dlist_write(vc4_state, 0xc0c0c0c0);
 209
 210         /* Pointer Word 0: RGB / Y Pointer */
 211         vc4_dlist_write(vc4_state, bo->paddr + offset);
 212
 213         /* Pointer Context Word 0: Written by the HVS */
 214         vc4_dlist_write(vc4_state, 0xc0c0c0c0);
 215
 216         /* Pitch word 0: Pointer 0 Pitch */
 217         vc4_dlist_write(vc4_state,
 218                         VC4_SET_FIELD(fb->pitches[0], SCALER_SRC_PITCH));
 219
 220         vc4_state->dlist[ctl0_offset] |=
 221                 VC4_SET_FIELD(vc4_state->dlist_count, SCALER_CTL0_SIZE);
 222
 223         return 0;
 224 }
 225
 226 /* If a modeset involves changing the setup of a plane, the atomic
 227  * infrastructure will call this to validate a proposed plane setup.
 228  * However, if a plane isn't getting updated, this (and the
 229  * corresponding vc4_plane_atomic_update) won't get called.  Thus, we
 230  * compute the dlist here and have all active plane dlists get updated
 231  * in the CRTC's flush.
 232  */
 233 static int vc4_plane_atomic_check(struct drm_plane *plane,
 234                                   struct drm_plane_state *state)
 235 {
 236         struct vc4_plane_state *vc4_state = to_vc4_plane_state(state);
 237
 238         vc4_state->dlist_count = 0;
 239
 240         if (plane_enabled(state))
 241                 return vc4_plane_mode_set(plane, state);
 242         else
 243                 return 0;
 244 }
 245
 246 static void vc4_plane_atomic_update(struct drm_plane *plane,
 247                                     struct drm_plane_state *old_state)
 248 {
 249         /* No contents here.  Since we don't know where in the CRTC's
 250          * dlist we should be stored, our dlist is uploaded to the
 251          * hardware with vc4_plane_write_dlist() at CRTC atomic_flush
 252          * time.
 253          */
 254 }
 255
 256 u32 vc4_plane_write_dlist(struct drm_plane *plane, u32 __iomem *dlist)
 257 {
 258         struct vc4_plane_state *vc4_state = to_vc4_plane_state(plane->state);
 259         int i;
 260
 261         /* Can't memcpy_toio() because it needs to be 32-bit writes. */
 262         for (i = 0; i < vc4_state->dlist_count; i++)
 263                 writel(vc4_state->dlist[i], &dlist[i]);
 264
 265         return vc4_state->dlist_count;
 266 }
 267
 268 u32 vc4_plane_dlist_size(struct drm_plane_state *state)
 269 {
 270         struct vc4_plane_state *vc4_state = to_vc4_plane_state(state);
 271
 272         return vc4_state->dlist_count;
 273 }
 274
 275 static const struct drm_plane_helper_funcs vc4_plane_helper_funcs = {
 276         .prepare_fb = NULL,
 277         .cleanup_fb = NULL,
 278         .atomic_check = vc4_plane_atomic_check,
 279         .atomic_update = vc4_plane_atomic_update,
 280 };
 281
 282 static void vc4_plane_destroy(struct drm_plane *plane)
 283 {
 284         drm_plane_helper_disable(plane);
 285         drm_plane_cleanup(plane);
 286 }
 287
 288 static const struct drm_plane_funcs vc4_plane_funcs = {
 289         .update_plane = drm_atomic_helper_update_plane,
 290         .disable_plane = drm_atomic_helper_disable_plane,
 291         .destroy = vc4_plane_destroy,
 292         .set_property = NULL,
 293         .reset = vc4_plane_reset,
 294         .atomic_duplicate_state = vc4_plane_duplicate_state,
 295         .atomic_destroy_state = vc4_plane_destroy_state,
 296 };
 297
 298 struct drm_plane *vc4_plane_init(struct drm_device *dev,
 299                                  enum drm_plane_type type)
 300 {
 301         struct drm_plane *plane = NULL;
 302         struct vc4_plane *vc4_plane;
 303         u32 formats[ARRAY_SIZE(hvs_formats)];
 304         int ret = 0;
 305         unsigned i;
 306
 307         vc4_plane = devm_kzalloc(dev->dev, sizeof(*vc4_plane),
 308                                  GFP_KERNEL);
 309         if (!vc4_plane) {
 310                 ret = -ENOMEM;
 311                 goto fail;
 312         }
 313
 314         for (i = 0; i < ARRAY_SIZE(hvs_formats); i++)
 315                 formats[i] = hvs_formats[i].drm;
 316         plane = &vc4_plane->base;
 317         ret = drm_universal_plane_init(dev, plane, 0xff,
 318                                        &vc4_plane_funcs,
 319                                        formats, ARRAY_SIZE(formats),
 320                                        type);
 321
 322         drm_plane_helper_add(plane, &vc4_plane_helper_funcs);
 323
 324         return plane;
 325 fail:
 326         if (plane)
 327                 vc4_plane_destroy(plane);
 328
 329         return ERR_PTR(ret);
 330 }