drivers/media/platform/vsp1/vsp1_uds.c

   1 /*
   2  * vsp1_uds.c  --  R-Car VSP1 Up and Down Scaler
   3  *
   4  * Copyright (C) 2013-2014 Renesas Electronics Corporation
   5  *
   6  * Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  */
  13
  14 #include <linux/device.h>
  15 #include <linux/gfp.h>
  16
  17 #include <media/v4l2-subdev.h>
  18
  19 #include "vsp1.h"
  20 #include "vsp1_dl.h"
  21 #include "vsp1_uds.h"
  22
  23 #define UDS_MIN_SIZE                            4U
  24 #define UDS_MAX_SIZE                            8190U
  25
  26 #define UDS_MIN_FACTOR                          0x0100
  27 #define UDS_MAX_FACTOR                          0xffff
  28
  29 /* -----------------------------------------------------------------------------
  30  * Device Access
  31  */
  32
  33 static inline void vsp1_uds_write(struct vsp1_uds *uds, struct vsp1_dl_list *dl,
  34                                   u32 reg, u32 data)
  35 {
  36         vsp1_dl_list_write(dl, reg + uds->entity.index * VI6_UDS_OFFSET, data);
  37 }
  38
  39 /* -----------------------------------------------------------------------------
  40  * Scaling Computation
  41  */
  42
  43 void vsp1_uds_set_alpha(struct vsp1_uds *uds, struct vsp1_dl_list *dl,
  44                         unsigned int alpha)
  45 {
  46         vsp1_uds_write(uds, dl, VI6_UDS_ALPVAL,
  47                        alpha << VI6_UDS_ALPVAL_VAL0_SHIFT);
  48 }
  49
  50 /*
  51  * uds_output_size - Return the output size for an input size and scaling ratio
  52  * @input: input size in pixels
  53  * @ratio: scaling ratio in U4.12 fixed-point format
  54  */
  55 static unsigned int uds_output_size(unsigned int input, unsigned int ratio)
  56 {
  57         if (ratio > 4096) {
  58                 /* Down-scaling */
  59                 unsigned int mp;
  60
  61                 mp = ratio / 4096;
  62                 mp = mp < 4 ? 1 : (mp < 8 ? 2 : 4);
  63
  64                 return (input - 1) / mp * mp * 4096 / ratio + 1;
  65         } else {
  66                 /* Up-scaling */
  67                 return (input - 1) * 4096 / ratio + 1;
  68         }
  69 }
  70
  71 /*
  72  * uds_output_limits - Return the min and max output sizes for an input size
  73  * @input: input size in pixels
  74  * @minimum: minimum output size (returned)
  75  * @maximum: maximum output size (returned)
  76  */
  77 static void uds_output_limits(unsigned int input,
  78                               unsigned int *minimum, unsigned int *maximum)
  79 {
  80         *minimum = max(uds_output_size(input, UDS_MAX_FACTOR), UDS_MIN_SIZE);
  81         *maximum = min(uds_output_size(input, UDS_MIN_FACTOR), UDS_MAX_SIZE);
  82 }
  83
  84 /*
  85  * uds_passband_width - Return the passband filter width for a scaling ratio
  86  * @ratio: scaling ratio in U4.12 fixed-point format
  87  */
  88 static unsigned int uds_passband_width(unsigned int ratio)
  89 {
  90         if (ratio >= 4096) {
  91                 /* Down-scaling */
  92                 unsigned int mp;
  93
  94                 mp = ratio / 4096;
  95                 mp = mp < 4 ? 1 : (mp < 8 ? 2 : 4);
  96
  97                 return 64 * 4096 * mp / ratio;
  98         } else {
  99                 /* Up-scaling */
 100                 return 64;
 101         }
 102 }
 103
 104 static unsigned int uds_compute_ratio(unsigned int input, unsigned int output)
 105 {
 106         /* TODO: This is an approximation that will need to be refined. */
 107         return (input - 1) * 4096 / (output - 1);
 108 }
 109
 110 /* -----------------------------------------------------------------------------
 111  * V4L2 Subdevice Pad Operations
 112  */
 113
 114 static int uds_enum_mbus_code(struct v4l2_subdev *subdev,
 115                               struct v4l2_subdev_pad_config *cfg,
 116                               struct v4l2_subdev_mbus_code_enum *code)
 117 {
 118         static const unsigned int codes[] = {
 119                 MEDIA_BUS_FMT_ARGB8888_1X32,
 120                 MEDIA_BUS_FMT_AYUV8_1X32,
 121         };
 122         struct vsp1_uds *uds = to_uds(subdev);
 123
 124         if (code->pad == UDS_PAD_SINK) {
 125                 if (code->index >= ARRAY_SIZE(codes))
 126                         return -EINVAL;
 127
 128                 code->code = codes[code->index];
 129         } else {
 130                 struct v4l2_subdev_pad_config *config;
 131                 struct v4l2_mbus_framefmt *format;
 132
 133                 config = vsp1_entity_get_pad_config(&uds->entity, cfg,
 134                                                     code->which);
 135                 if (!config)
 136                         return -EINVAL;
 137
 138                 /* The UDS can't perform format conversion, the sink format is
 139                  * always identical to the source format.
 140                  */
 141                 if (code->index)
 142                         return -EINVAL;
 143
 144                 format = vsp1_entity_get_pad_format(&uds->entity, config,
 145                                                     UDS_PAD_SINK);
 146                 code->code = format->code;
 147         }
 148
 149         return 0;
 150 }
 151
 152 static int uds_enum_frame_size(struct v4l2_subdev *subdev,
 153                                struct v4l2_subdev_pad_config *cfg,
 154                                struct v4l2_subdev_frame_size_enum *fse)
 155 {
 156         struct vsp1_uds *uds = to_uds(subdev);
 157         struct v4l2_subdev_pad_config *config;
 158         struct v4l2_mbus_framefmt *format;
 159
 160         config = vsp1_entity_get_pad_config(&uds->entity, cfg, fse->which);
 161         if (!config)
 162                 return -EINVAL;
 163
 164         format = vsp1_entity_get_pad_format(&uds->entity, config,
 165                                             UDS_PAD_SINK);
 166
 167         if (fse->index || fse->code != format->code)
 168                 return -EINVAL;
 169
 170         if (fse->pad == UDS_PAD_SINK) {
 171                 fse->min_width = UDS_MIN_SIZE;
 172                 fse->max_width = UDS_MAX_SIZE;
 173                 fse->min_height = UDS_MIN_SIZE;
 174                 fse->max_height = UDS_MAX_SIZE;
 175         } else {
 176                 uds_output_limits(format->width, &fse->min_width,
 177                                   &fse->max_width);
 178                 uds_output_limits(format->height, &fse->min_height,
 179                                   &fse->max_height);
 180         }
 181
 182         return 0;
 183 }
 184
 185 static int uds_get_format(struct v4l2_subdev *subdev,
 186                           struct v4l2_subdev_pad_config *cfg,
 187                           struct v4l2_subdev_format *fmt)
 188 {
 189         struct vsp1_uds *uds = to_uds(subdev);
 190         struct v4l2_subdev_pad_config *config;
 191
 192         config = vsp1_entity_get_pad_config(&uds->entity, cfg, fmt->which);
 193         if (!config)
 194                 return -EINVAL;
 195
 196         fmt->format = *vsp1_entity_get_pad_format(&uds->entity, config,
 197                                                   fmt->pad);
 198
 199         return 0;
 200 }
 201
 202 static void uds_try_format(struct vsp1_uds *uds,
 203                            struct v4l2_subdev_pad_config *config,
 204                            unsigned int pad, struct v4l2_mbus_framefmt *fmt)
 205 {
 206         struct v4l2_mbus_framefmt *format;
 207         unsigned int minimum;
 208         unsigned int maximum;
 209
 210         switch (pad) {
 211         case UDS_PAD_SINK:
 212                 /* Default to YUV if the requested format is not supported. */
 213                 if (fmt->code != MEDIA_BUS_FMT_ARGB8888_1X32 &&
 214                     fmt->code != MEDIA_BUS_FMT_AYUV8_1X32)
 215                         fmt->code = MEDIA_BUS_FMT_AYUV8_1X32;
 216
 217                 fmt->width = clamp(fmt->width, UDS_MIN_SIZE, UDS_MAX_SIZE);
 218                 fmt->height = clamp(fmt->height, UDS_MIN_SIZE, UDS_MAX_SIZE);
 219                 break;
 220
 221         case UDS_PAD_SOURCE:
 222                 /* The UDS scales but can't perform format conversion. */
 223                 format = vsp1_entity_get_pad_format(&uds->entity, config,
 224                                                     UDS_PAD_SINK);
 225                 fmt->code = format->code;
 226
 227                 uds_output_limits(format->width, &minimum, &maximum);
 228                 fmt->width = clamp(fmt->width, minimum, maximum);
 229                 uds_output_limits(format->height, &minimum, &maximum);
 230                 fmt->height = clamp(fmt->height, minimum, maximum);
 231                 break;
 232         }
 233
 234         fmt->field = V4L2_FIELD_NONE;
 235         fmt->colorspace = V4L2_COLORSPACE_SRGB;
 236 }
 237
 238 static int uds_set_format(struct v4l2_subdev *subdev,
 239                           struct v4l2_subdev_pad_config *cfg,
 240                           struct v4l2_subdev_format *fmt)
 241 {
 242         struct vsp1_uds *uds = to_uds(subdev);
 243         struct v4l2_subdev_pad_config *config;
 244         struct v4l2_mbus_framefmt *format;
 245
 246         config = vsp1_entity_get_pad_config(&uds->entity, cfg, fmt->which);
 247         if (!config)
 248                 return -EINVAL;
 249
 250         uds_try_format(uds, config, fmt->pad, &fmt->format);
 251
 252         format = vsp1_entity_get_pad_format(&uds->entity, config, fmt->pad);
 253         *format = fmt->format;
 254
 255         if (fmt->pad == UDS_PAD_SINK) {
 256                 /* Propagate the format to the source pad. */
 257                 format = vsp1_entity_get_pad_format(&uds->entity, config,
 258                                                     UDS_PAD_SOURCE);
 259                 *format = fmt->format;
 260
 261                 uds_try_format(uds, config, UDS_PAD_SOURCE, format);
 262         }
 263
 264         return 0;
 265 }
 266
 267 /* -----------------------------------------------------------------------------
 268  * V4L2 Subdevice Operations
 269  */
 270
 271 static struct v4l2_subdev_pad_ops uds_pad_ops = {
 272         .init_cfg = vsp1_entity_init_cfg,
 273         .enum_mbus_code = uds_enum_mbus_code,
 274         .enum_frame_size = uds_enum_frame_size,
 275         .get_fmt = uds_get_format,
 276         .set_fmt = uds_set_format,
 277 };
 278
 279 static struct v4l2_subdev_ops uds_ops = {
 280         .pad    = &uds_pad_ops,
 281 };
 282
 283 /* -----------------------------------------------------------------------------
 284  * VSP1 Entity Operations
 285  */
 286
 287 static void uds_configure(struct vsp1_entity *entity,
 288                           struct vsp1_pipeline *pipe,
 289                           struct vsp1_dl_list *dl)
 290 {
 291         struct vsp1_uds *uds = to_uds(&entity->subdev);
 292         const struct v4l2_mbus_framefmt *output;
 293         const struct v4l2_mbus_framefmt *input;
 294         unsigned int hscale;
 295         unsigned int vscale;
 296         bool multitap;
 297
 298         input = vsp1_entity_get_pad_format(&uds->entity, uds->entity.config,
 299                                            UDS_PAD_SINK);
 300         output = vsp1_entity_get_pad_format(&uds->entity, uds->entity.config,
 301                                             UDS_PAD_SOURCE);
 302
 303         hscale = uds_compute_ratio(input->width, output->width);
 304         vscale = uds_compute_ratio(input->height, output->height);
 305
 306         dev_dbg(uds->entity.vsp1->dev, "hscale %u vscale %u\n", hscale, vscale);
 307
 308         /* Multi-tap scaling can't be enabled along with alpha scaling when
 309          * scaling down with a factor lower than or equal to 1/2 in either
 310          * direction.
 311          */
 312         if (uds->scale_alpha && (hscale >= 8192 || vscale >= 8192))
 313                 multitap = false;
 314         else
 315                 multitap = true;
 316
 317         vsp1_uds_write(uds, dl, VI6_UDS_CTRL,
 318                        (uds->scale_alpha ? VI6_UDS_CTRL_AON : 0) |
 319                        (multitap ? VI6_UDS_CTRL_BC : 0));
 320
 321         vsp1_uds_write(uds, dl, VI6_UDS_PASS_BWIDTH,
 322                        (uds_passband_width(hscale)
 323                                 << VI6_UDS_PASS_BWIDTH_H_SHIFT) |
 324                        (uds_passband_width(vscale)
 325                                 << VI6_UDS_PASS_BWIDTH_V_SHIFT));
 326
 327         /* Set the scaling ratios and the output size. */
 328         vsp1_uds_write(uds, dl, VI6_UDS_SCALE,
 329                        (hscale << VI6_UDS_SCALE_HFRAC_SHIFT) |
 330                        (vscale << VI6_UDS_SCALE_VFRAC_SHIFT));
 331         vsp1_uds_write(uds, dl, VI6_UDS_CLIP_SIZE,
 332                        (output->width << VI6_UDS_CLIP_SIZE_HSIZE_SHIFT) |
 333                        (output->height << VI6_UDS_CLIP_SIZE_VSIZE_SHIFT));
 334 }
 335
 336 static const struct vsp1_entity_operations uds_entity_ops = {
 337         .configure = uds_configure,
 338 };
 339
 340 /* -----------------------------------------------------------------------------
 341  * Initialization and Cleanup
 342  */
 343
 344 struct vsp1_uds *vsp1_uds_create(struct vsp1_device *vsp1, unsigned int index)
 345 {
 346         struct vsp1_uds *uds;
 347         char name[6];
 348         int ret;
 349
 350         uds = devm_kzalloc(vsp1->dev, sizeof(*uds), GFP_KERNEL);
 351         if (uds == NULL)
 352                 return ERR_PTR(-ENOMEM);
 353
 354         uds->entity.ops = &uds_entity_ops;
 355         uds->entity.type = VSP1_ENTITY_UDS;
 356         uds->entity.index = index;
 357
 358         sprintf(name, "uds.%u", index);
 359         ret = vsp1_entity_init(vsp1, &uds->entity, name, 2, &uds_ops);
 360         if (ret < 0)
 361                 return ERR_PTR(ret);
 362
 363         return uds;
 364 }