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_entity *entity, struct vsp1_dl_list *dl,
  44                         unsigned int alpha)
  45 {
  46         struct vsp1_uds *uds = to_uds(&entity->subdev);
  47
  48         vsp1_uds_write(uds, dl, VI6_UDS_ALPVAL,
  49                        alpha << VI6_UDS_ALPVAL_VAL0_SHIFT);
  50 }
  51
  52 /*
  53  * uds_output_size - Return the output size for an input size and scaling ratio
  54  * @input: input size in pixels
  55  * @ratio: scaling ratio in U4.12 fixed-point format
  56  */
  57 static unsigned int uds_output_size(unsigned int input, unsigned int ratio)
  58 {
  59         if (ratio > 4096) {
  60                 /* Down-scaling */
  61                 unsigned int mp;
  62
  63                 mp = ratio / 4096;
  64                 mp = mp < 4 ? 1 : (mp < 8 ? 2 : 4);
  65
  66                 return (input - 1) / mp * mp * 4096 / ratio + 1;
  67         } else {
  68                 /* Up-scaling */
  69                 return (input - 1) * 4096 / ratio + 1;
  70         }
  71 }
  72
  73 /*
  74  * uds_output_limits - Return the min and max output sizes for an input size
  75  * @input: input size in pixels
  76  * @minimum: minimum output size (returned)
  77  * @maximum: maximum output size (returned)
  78  */
  79 static void uds_output_limits(unsigned int input,
  80                               unsigned int *minimum, unsigned int *maximum)
  81 {
  82         *minimum = max(uds_output_size(input, UDS_MAX_FACTOR), UDS_MIN_SIZE);
  83         *maximum = min(uds_output_size(input, UDS_MIN_FACTOR), UDS_MAX_SIZE);
  84 }
  85
  86 /*
  87  * uds_passband_width - Return the passband filter width for a scaling ratio
  88  * @ratio: scaling ratio in U4.12 fixed-point format
  89  */
  90 static unsigned int uds_passband_width(unsigned int ratio)
  91 {
  92         if (ratio >= 4096) {
  93                 /* Down-scaling */
  94                 unsigned int mp;
  95
  96                 mp = ratio / 4096;
  97                 mp = mp < 4 ? 1 : (mp < 8 ? 2 : 4);
  98
  99                 return 64 * 4096 * mp / ratio;
 100         } else {
 101                 /* Up-scaling */
 102                 return 64;
 103         }
 104 }
 105
 106 static unsigned int uds_compute_ratio(unsigned int input, unsigned int output)
 107 {
 108         /* TODO: This is an approximation that will need to be refined. */
 109         return (input - 1) * 4096 / (output - 1);
 110 }
 111
 112 /* -----------------------------------------------------------------------------
 113  * V4L2 Subdevice Pad Operations
 114  */
 115
 116 static int uds_enum_mbus_code(struct v4l2_subdev *subdev,
 117                               struct v4l2_subdev_pad_config *cfg,
 118                               struct v4l2_subdev_mbus_code_enum *code)
 119 {
 120         static const unsigned int codes[] = {
 121                 MEDIA_BUS_FMT_ARGB8888_1X32,
 122                 MEDIA_BUS_FMT_AYUV8_1X32,
 123         };
 124
 125         return vsp1_subdev_enum_mbus_code(subdev, cfg, code, codes,
 126                                           ARRAY_SIZE(codes));
 127 }
 128
 129 static int uds_enum_frame_size(struct v4l2_subdev *subdev,
 130                                struct v4l2_subdev_pad_config *cfg,
 131                                struct v4l2_subdev_frame_size_enum *fse)
 132 {
 133         struct vsp1_uds *uds = to_uds(subdev);
 134         struct v4l2_subdev_pad_config *config;
 135         struct v4l2_mbus_framefmt *format;
 136
 137         config = vsp1_entity_get_pad_config(&uds->entity, cfg, fse->which);
 138         if (!config)
 139                 return -EINVAL;
 140
 141         format = vsp1_entity_get_pad_format(&uds->entity, config,
 142                                             UDS_PAD_SINK);
 143
 144         if (fse->index || fse->code != format->code)
 145                 return -EINVAL;
 146
 147         if (fse->pad == UDS_PAD_SINK) {
 148                 fse->min_width = UDS_MIN_SIZE;
 149                 fse->max_width = UDS_MAX_SIZE;
 150                 fse->min_height = UDS_MIN_SIZE;
 151                 fse->max_height = UDS_MAX_SIZE;
 152         } else {
 153                 uds_output_limits(format->width, &fse->min_width,
 154                                   &fse->max_width);
 155                 uds_output_limits(format->height, &fse->min_height,
 156                                   &fse->max_height);
 157         }
 158
 159         return 0;
 160 }
 161
 162 static void uds_try_format(struct vsp1_uds *uds,
 163                            struct v4l2_subdev_pad_config *config,
 164                            unsigned int pad, struct v4l2_mbus_framefmt *fmt)
 165 {
 166         struct v4l2_mbus_framefmt *format;
 167         unsigned int minimum;
 168         unsigned int maximum;
 169
 170         switch (pad) {
 171         case UDS_PAD_SINK:
 172                 /* Default to YUV if the requested format is not supported. */
 173                 if (fmt->code != MEDIA_BUS_FMT_ARGB8888_1X32 &&
 174                     fmt->code != MEDIA_BUS_FMT_AYUV8_1X32)
 175                         fmt->code = MEDIA_BUS_FMT_AYUV8_1X32;
 176
 177                 fmt->width = clamp(fmt->width, UDS_MIN_SIZE, UDS_MAX_SIZE);
 178                 fmt->height = clamp(fmt->height, UDS_MIN_SIZE, UDS_MAX_SIZE);
 179                 break;
 180
 181         case UDS_PAD_SOURCE:
 182                 /* The UDS scales but can't perform format conversion. */
 183                 format = vsp1_entity_get_pad_format(&uds->entity, config,
 184                                                     UDS_PAD_SINK);
 185                 fmt->code = format->code;
 186
 187                 uds_output_limits(format->width, &minimum, &maximum);
 188                 fmt->width = clamp(fmt->width, minimum, maximum);
 189                 uds_output_limits(format->height, &minimum, &maximum);
 190                 fmt->height = clamp(fmt->height, minimum, maximum);
 191                 break;
 192         }
 193
 194         fmt->field = V4L2_FIELD_NONE;
 195         fmt->colorspace = V4L2_COLORSPACE_SRGB;
 196 }
 197
 198 static int uds_set_format(struct v4l2_subdev *subdev,
 199                           struct v4l2_subdev_pad_config *cfg,
 200                           struct v4l2_subdev_format *fmt)
 201 {
 202         struct vsp1_uds *uds = to_uds(subdev);
 203         struct v4l2_subdev_pad_config *config;
 204         struct v4l2_mbus_framefmt *format;
 205
 206         config = vsp1_entity_get_pad_config(&uds->entity, cfg, fmt->which);
 207         if (!config)
 208                 return -EINVAL;
 209
 210         uds_try_format(uds, config, fmt->pad, &fmt->format);
 211
 212         format = vsp1_entity_get_pad_format(&uds->entity, config, fmt->pad);
 213         *format = fmt->format;
 214
 215         if (fmt->pad == UDS_PAD_SINK) {
 216                 /* Propagate the format to the source pad. */
 217                 format = vsp1_entity_get_pad_format(&uds->entity, config,
 218                                                     UDS_PAD_SOURCE);
 219                 *format = fmt->format;
 220
 221                 uds_try_format(uds, config, UDS_PAD_SOURCE, format);
 222         }
 223
 224         return 0;
 225 }
 226
 227 /* -----------------------------------------------------------------------------
 228  * V4L2 Subdevice Operations
 229  */
 230
 231 static const struct v4l2_subdev_pad_ops uds_pad_ops = {
 232         .init_cfg = vsp1_entity_init_cfg,
 233         .enum_mbus_code = uds_enum_mbus_code,
 234         .enum_frame_size = uds_enum_frame_size,
 235         .get_fmt = vsp1_subdev_get_pad_format,
 236         .set_fmt = uds_set_format,
 237 };
 238
 239 static const struct v4l2_subdev_ops uds_ops = {
 240         .pad    = &uds_pad_ops,
 241 };
 242
 243 /* -----------------------------------------------------------------------------
 244  * VSP1 Entity Operations
 245  */
 246
 247 static void uds_configure(struct vsp1_entity *entity,
 248                           struct vsp1_pipeline *pipe,
 249                           struct vsp1_dl_list *dl, bool full)
 250 {
 251         struct vsp1_uds *uds = to_uds(&entity->subdev);
 252         const struct v4l2_mbus_framefmt *output;
 253         const struct v4l2_mbus_framefmt *input;
 254         unsigned int hscale;
 255         unsigned int vscale;
 256         bool multitap;
 257
 258         if (!full)
 259                 return;
 260
 261         input = vsp1_entity_get_pad_format(&uds->entity, uds->entity.config,
 262                                            UDS_PAD_SINK);
 263         output = vsp1_entity_get_pad_format(&uds->entity, uds->entity.config,
 264                                             UDS_PAD_SOURCE);
 265
 266         hscale = uds_compute_ratio(input->width, output->width);
 267         vscale = uds_compute_ratio(input->height, output->height);
 268
 269         dev_dbg(uds->entity.vsp1->dev, "hscale %u vscale %u\n", hscale, vscale);
 270
 271         /* Multi-tap scaling can't be enabled along with alpha scaling when
 272          * scaling down with a factor lower than or equal to 1/2 in either
 273          * direction.
 274          */
 275         if (uds->scale_alpha && (hscale >= 8192 || vscale >= 8192))
 276                 multitap = false;
 277         else
 278                 multitap = true;
 279
 280         vsp1_uds_write(uds, dl, VI6_UDS_CTRL,
 281                        (uds->scale_alpha ? VI6_UDS_CTRL_AON : 0) |
 282                        (multitap ? VI6_UDS_CTRL_BC : 0));
 283
 284         vsp1_uds_write(uds, dl, VI6_UDS_PASS_BWIDTH,
 285                        (uds_passband_width(hscale)
 286                                 << VI6_UDS_PASS_BWIDTH_H_SHIFT) |
 287                        (uds_passband_width(vscale)
 288                                 << VI6_UDS_PASS_BWIDTH_V_SHIFT));
 289
 290         /* Set the scaling ratios and the output size. */
 291         vsp1_uds_write(uds, dl, VI6_UDS_SCALE,
 292                        (hscale << VI6_UDS_SCALE_HFRAC_SHIFT) |
 293                        (vscale << VI6_UDS_SCALE_VFRAC_SHIFT));
 294         vsp1_uds_write(uds, dl, VI6_UDS_CLIP_SIZE,
 295                        (output->width << VI6_UDS_CLIP_SIZE_HSIZE_SHIFT) |
 296                        (output->height << VI6_UDS_CLIP_SIZE_VSIZE_SHIFT));
 297 }
 298
 299 static const struct vsp1_entity_operations uds_entity_ops = {
 300         .configure = uds_configure,
 301 };
 302
 303 /* -----------------------------------------------------------------------------
 304  * Initialization and Cleanup
 305  */
 306
 307 struct vsp1_uds *vsp1_uds_create(struct vsp1_device *vsp1, unsigned int index)
 308 {
 309         struct vsp1_uds *uds;
 310         char name[6];
 311         int ret;
 312
 313         uds = devm_kzalloc(vsp1->dev, sizeof(*uds), GFP_KERNEL);
 314         if (uds == NULL)
 315                 return ERR_PTR(-ENOMEM);
 316
 317         uds->entity.ops = &uds_entity_ops;
 318         uds->entity.type = VSP1_ENTITY_UDS;
 319         uds->entity.index = index;
 320
 321         sprintf(name, "uds.%u", index);
 322         ret = vsp1_entity_init(vsp1, &uds->entity, name, 2, &uds_ops,
 323                                MEDIA_ENT_F_PROC_VIDEO_SCALER);
 324         if (ret < 0)
 325                 return ERR_PTR(ret);
 326
 327         return uds;
 328 }