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
 123         return vsp1_subdev_enum_mbus_code(subdev, cfg, code, codes,
 124                                           ARRAY_SIZE(codes));
 125 }
 126
 127 static int uds_enum_frame_size(struct v4l2_subdev *subdev,
 128                                struct v4l2_subdev_pad_config *cfg,
 129                                struct v4l2_subdev_frame_size_enum *fse)
 130 {
 131         struct vsp1_uds *uds = to_uds(subdev);
 132         struct v4l2_subdev_pad_config *config;
 133         struct v4l2_mbus_framefmt *format;
 134
 135         config = vsp1_entity_get_pad_config(&uds->entity, cfg, fse->which);
 136         if (!config)
 137                 return -EINVAL;
 138
 139         format = vsp1_entity_get_pad_format(&uds->entity, config,
 140                                             UDS_PAD_SINK);
 141
 142         if (fse->index || fse->code != format->code)
 143                 return -EINVAL;
 144
 145         if (fse->pad == UDS_PAD_SINK) {
 146                 fse->min_width = UDS_MIN_SIZE;
 147                 fse->max_width = UDS_MAX_SIZE;
 148                 fse->min_height = UDS_MIN_SIZE;
 149                 fse->max_height = UDS_MAX_SIZE;
 150         } else {
 151                 uds_output_limits(format->width, &fse->min_width,
 152                                   &fse->max_width);
 153                 uds_output_limits(format->height, &fse->min_height,
 154                                   &fse->max_height);
 155         }
 156
 157         return 0;
 158 }
 159
 160 static void uds_try_format(struct vsp1_uds *uds,
 161                            struct v4l2_subdev_pad_config *config,
 162                            unsigned int pad, struct v4l2_mbus_framefmt *fmt)
 163 {
 164         struct v4l2_mbus_framefmt *format;
 165         unsigned int minimum;
 166         unsigned int maximum;
 167
 168         switch (pad) {
 169         case UDS_PAD_SINK:
 170                 /* Default to YUV if the requested format is not supported. */
 171                 if (fmt->code != MEDIA_BUS_FMT_ARGB8888_1X32 &&
 172                     fmt->code != MEDIA_BUS_FMT_AYUV8_1X32)
 173                         fmt->code = MEDIA_BUS_FMT_AYUV8_1X32;
 174
 175                 fmt->width = clamp(fmt->width, UDS_MIN_SIZE, UDS_MAX_SIZE);
 176                 fmt->height = clamp(fmt->height, UDS_MIN_SIZE, UDS_MAX_SIZE);
 177                 break;
 178
 179         case UDS_PAD_SOURCE:
 180                 /* The UDS scales but can't perform format conversion. */
 181                 format = vsp1_entity_get_pad_format(&uds->entity, config,
 182                                                     UDS_PAD_SINK);
 183                 fmt->code = format->code;
 184
 185                 uds_output_limits(format->width, &minimum, &maximum);
 186                 fmt->width = clamp(fmt->width, minimum, maximum);
 187                 uds_output_limits(format->height, &minimum, &maximum);
 188                 fmt->height = clamp(fmt->height, minimum, maximum);
 189                 break;
 190         }
 191
 192         fmt->field = V4L2_FIELD_NONE;
 193         fmt->colorspace = V4L2_COLORSPACE_SRGB;
 194 }
 195
 196 static int uds_set_format(struct v4l2_subdev *subdev,
 197                           struct v4l2_subdev_pad_config *cfg,
 198                           struct v4l2_subdev_format *fmt)
 199 {
 200         struct vsp1_uds *uds = to_uds(subdev);
 201         struct v4l2_subdev_pad_config *config;
 202         struct v4l2_mbus_framefmt *format;
 203
 204         config = vsp1_entity_get_pad_config(&uds->entity, cfg, fmt->which);
 205         if (!config)
 206                 return -EINVAL;
 207
 208         uds_try_format(uds, config, fmt->pad, &fmt->format);
 209
 210         format = vsp1_entity_get_pad_format(&uds->entity, config, fmt->pad);
 211         *format = fmt->format;
 212
 213         if (fmt->pad == UDS_PAD_SINK) {
 214                 /* Propagate the format to the source pad. */
 215                 format = vsp1_entity_get_pad_format(&uds->entity, config,
 216                                                     UDS_PAD_SOURCE);
 217                 *format = fmt->format;
 218
 219                 uds_try_format(uds, config, UDS_PAD_SOURCE, format);
 220         }
 221
 222         return 0;
 223 }
 224
 225 /* -----------------------------------------------------------------------------
 226  * V4L2 Subdevice Operations
 227  */
 228
 229 static const struct v4l2_subdev_pad_ops uds_pad_ops = {
 230         .init_cfg = vsp1_entity_init_cfg,
 231         .enum_mbus_code = uds_enum_mbus_code,
 232         .enum_frame_size = uds_enum_frame_size,
 233         .get_fmt = vsp1_subdev_get_pad_format,
 234         .set_fmt = uds_set_format,
 235 };
 236
 237 static const struct v4l2_subdev_ops uds_ops = {
 238         .pad    = &uds_pad_ops,
 239 };
 240
 241 /* -----------------------------------------------------------------------------
 242  * VSP1 Entity Operations
 243  */
 244
 245 static void uds_configure(struct vsp1_entity *entity,
 246                           struct vsp1_pipeline *pipe,
 247                           struct vsp1_dl_list *dl, bool full)
 248 {
 249         struct vsp1_uds *uds = to_uds(&entity->subdev);
 250         const struct v4l2_mbus_framefmt *output;
 251         const struct v4l2_mbus_framefmt *input;
 252         unsigned int hscale;
 253         unsigned int vscale;
 254         bool multitap;
 255
 256         if (!full)
 257                 return;
 258
 259         input = vsp1_entity_get_pad_format(&uds->entity, uds->entity.config,
 260                                            UDS_PAD_SINK);
 261         output = vsp1_entity_get_pad_format(&uds->entity, uds->entity.config,
 262                                             UDS_PAD_SOURCE);
 263
 264         hscale = uds_compute_ratio(input->width, output->width);
 265         vscale = uds_compute_ratio(input->height, output->height);
 266
 267         dev_dbg(uds->entity.vsp1->dev, "hscale %u vscale %u\n", hscale, vscale);
 268
 269         /* Multi-tap scaling can't be enabled along with alpha scaling when
 270          * scaling down with a factor lower than or equal to 1/2 in either
 271          * direction.
 272          */
 273         if (uds->scale_alpha && (hscale >= 8192 || vscale >= 8192))
 274                 multitap = false;
 275         else
 276                 multitap = true;
 277
 278         vsp1_uds_write(uds, dl, VI6_UDS_CTRL,
 279                        (uds->scale_alpha ? VI6_UDS_CTRL_AON : 0) |
 280                        (multitap ? VI6_UDS_CTRL_BC : 0));
 281
 282         vsp1_uds_write(uds, dl, VI6_UDS_PASS_BWIDTH,
 283                        (uds_passband_width(hscale)
 284                                 << VI6_UDS_PASS_BWIDTH_H_SHIFT) |
 285                        (uds_passband_width(vscale)
 286                                 << VI6_UDS_PASS_BWIDTH_V_SHIFT));
 287
 288         /* Set the scaling ratios and the output size. */
 289         vsp1_uds_write(uds, dl, VI6_UDS_SCALE,
 290                        (hscale << VI6_UDS_SCALE_HFRAC_SHIFT) |
 291                        (vscale << VI6_UDS_SCALE_VFRAC_SHIFT));
 292         vsp1_uds_write(uds, dl, VI6_UDS_CLIP_SIZE,
 293                        (output->width << VI6_UDS_CLIP_SIZE_HSIZE_SHIFT) |
 294                        (output->height << VI6_UDS_CLIP_SIZE_VSIZE_SHIFT));
 295 }
 296
 297 static const struct vsp1_entity_operations uds_entity_ops = {
 298         .configure = uds_configure,
 299 };
 300
 301 /* -----------------------------------------------------------------------------
 302  * Initialization and Cleanup
 303  */
 304
 305 struct vsp1_uds *vsp1_uds_create(struct vsp1_device *vsp1, unsigned int index)
 306 {
 307         struct vsp1_uds *uds;
 308         char name[6];
 309         int ret;
 310
 311         uds = devm_kzalloc(vsp1->dev, sizeof(*uds), GFP_KERNEL);
 312         if (uds == NULL)
 313                 return ERR_PTR(-ENOMEM);
 314
 315         uds->entity.ops = &uds_entity_ops;
 316         uds->entity.type = VSP1_ENTITY_UDS;
 317         uds->entity.index = index;
 318
 319         sprintf(name, "uds.%u", index);
 320         ret = vsp1_entity_init(vsp1, &uds->entity, name, 2, &uds_ops,
 321                                MEDIA_ENT_F_PROC_VIDEO_SCALER);
 322         if (ret < 0)
 323                 return ERR_PTR(ret);
 324
 325         return uds;
 326 }