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_uds.h"
21
22 #define UDS_MIN_SIZE 4U
23 #define UDS_MAX_SIZE 8190U
24
25 #define UDS_MIN_FACTOR 0x0100
26 #define UDS_MAX_FACTOR 0xffff
27
28 /* -----------------------------------------------------------------------------
29 * Device Access
30 */
31
vsp1_uds_read(struct vsp1_uds * uds,u32 reg)32 static inline u32 vsp1_uds_read(struct vsp1_uds *uds, u32 reg)
33 {
34 return vsp1_read(uds->entity.vsp1,
35 reg + uds->entity.index * VI6_UDS_OFFSET);
36 }
37
vsp1_uds_write(struct vsp1_uds * uds,u32 reg,u32 data)38 static inline void vsp1_uds_write(struct vsp1_uds *uds, u32 reg, u32 data)
39 {
40 vsp1_write(uds->entity.vsp1,
41 reg + uds->entity.index * VI6_UDS_OFFSET, data);
42 }
43
44 /* -----------------------------------------------------------------------------
45 * Scaling Computation
46 */
47
vsp1_uds_set_alpha(struct vsp1_uds * uds,unsigned int alpha)48 void vsp1_uds_set_alpha(struct vsp1_uds *uds, unsigned int alpha)
49 {
50 vsp1_uds_write(uds, VI6_UDS_ALPVAL, alpha << VI6_UDS_ALPVAL_VAL0_SHIFT);
51 }
52
53 /*
54 * uds_output_size - Return the output size for an input size and scaling ratio
55 * @input: input size in pixels
56 * @ratio: scaling ratio in U4.12 fixed-point format
57 */
uds_output_size(unsigned int input,unsigned int ratio)58 static unsigned int uds_output_size(unsigned int input, unsigned int ratio)
59 {
60 if (ratio > 4096) {
61 /* Down-scaling */
62 unsigned int mp;
63
64 mp = ratio / 4096;
65 mp = mp < 4 ? 1 : (mp < 8 ? 2 : 4);
66
67 return (input - 1) / mp * mp * 4096 / ratio + 1;
68 } else {
69 /* Up-scaling */
70 return (input - 1) * 4096 / ratio + 1;
71 }
72 }
73
74 /*
75 * uds_output_limits - Return the min and max output sizes for an input size
76 * @input: input size in pixels
77 * @minimum: minimum output size (returned)
78 * @maximum: maximum output size (returned)
79 */
uds_output_limits(unsigned int input,unsigned int * minimum,unsigned int * maximum)80 static void uds_output_limits(unsigned int input,
81 unsigned int *minimum, unsigned int *maximum)
82 {
83 *minimum = max(uds_output_size(input, UDS_MAX_FACTOR), UDS_MIN_SIZE);
84 *maximum = min(uds_output_size(input, UDS_MIN_FACTOR), UDS_MAX_SIZE);
85 }
86
87 /*
88 * uds_passband_width - Return the passband filter width for a scaling ratio
89 * @ratio: scaling ratio in U4.12 fixed-point format
90 */
uds_passband_width(unsigned int ratio)91 static unsigned int uds_passband_width(unsigned int ratio)
92 {
93 if (ratio >= 4096) {
94 /* Down-scaling */
95 unsigned int mp;
96
97 mp = ratio / 4096;
98 mp = mp < 4 ? 1 : (mp < 8 ? 2 : 4);
99
100 return 64 * 4096 * mp / ratio;
101 } else {
102 /* Up-scaling */
103 return 64;
104 }
105 }
106
uds_compute_ratio(unsigned int input,unsigned int output)107 static unsigned int uds_compute_ratio(unsigned int input, unsigned int output)
108 {
109 /* TODO: This is an approximation that will need to be refined. */
110 return (input - 1) * 4096 / (output - 1);
111 }
112
113 /* -----------------------------------------------------------------------------
114 * V4L2 Subdevice Core Operations
115 */
116
uds_s_stream(struct v4l2_subdev * subdev,int enable)117 static int uds_s_stream(struct v4l2_subdev *subdev, int enable)
118 {
119 struct vsp1_uds *uds = to_uds(subdev);
120 const struct v4l2_mbus_framefmt *output;
121 const struct v4l2_mbus_framefmt *input;
122 unsigned int hscale;
123 unsigned int vscale;
124 bool multitap;
125
126 if (!enable)
127 return 0;
128
129 input = &uds->entity.formats[UDS_PAD_SINK];
130 output = &uds->entity.formats[UDS_PAD_SOURCE];
131
132 hscale = uds_compute_ratio(input->width, output->width);
133 vscale = uds_compute_ratio(input->height, output->height);
134
135 dev_dbg(uds->entity.vsp1->dev, "hscale %u vscale %u\n", hscale, vscale);
136
137 /* Multi-tap scaling can't be enabled along with alpha scaling when
138 * scaling down with a factor lower than or equal to 1/2 in either
139 * direction.
140 */
141 if (uds->scale_alpha && (hscale >= 8192 || vscale >= 8192))
142 multitap = false;
143 else
144 multitap = true;
145
146 vsp1_uds_write(uds, VI6_UDS_CTRL,
147 (uds->scale_alpha ? VI6_UDS_CTRL_AON : 0) |
148 (multitap ? VI6_UDS_CTRL_BC : 0));
149
150 vsp1_uds_write(uds, VI6_UDS_PASS_BWIDTH,
151 (uds_passband_width(hscale)
152 << VI6_UDS_PASS_BWIDTH_H_SHIFT) |
153 (uds_passband_width(vscale)
154 << VI6_UDS_PASS_BWIDTH_V_SHIFT));
155
156 /* Set the scaling ratios and the output size. */
157 vsp1_uds_write(uds, VI6_UDS_SCALE,
158 (hscale << VI6_UDS_SCALE_HFRAC_SHIFT) |
159 (vscale << VI6_UDS_SCALE_VFRAC_SHIFT));
160 vsp1_uds_write(uds, VI6_UDS_CLIP_SIZE,
161 (output->width << VI6_UDS_CLIP_SIZE_HSIZE_SHIFT) |
162 (output->height << VI6_UDS_CLIP_SIZE_VSIZE_SHIFT));
163
164 return 0;
165 }
166
167 /* -----------------------------------------------------------------------------
168 * V4L2 Subdevice Pad Operations
169 */
170
uds_enum_mbus_code(struct v4l2_subdev * subdev,struct v4l2_subdev_fh * fh,struct v4l2_subdev_mbus_code_enum * code)171 static int uds_enum_mbus_code(struct v4l2_subdev *subdev,
172 struct v4l2_subdev_fh *fh,
173 struct v4l2_subdev_mbus_code_enum *code)
174 {
175 static const unsigned int codes[] = {
176 V4L2_MBUS_FMT_ARGB8888_1X32,
177 V4L2_MBUS_FMT_AYUV8_1X32,
178 };
179
180 if (code->pad == UDS_PAD_SINK) {
181 if (code->index >= ARRAY_SIZE(codes))
182 return -EINVAL;
183
184 code->code = codes[code->index];
185 } else {
186 struct v4l2_mbus_framefmt *format;
187
188 /* The UDS can't perform format conversion, the sink format is
189 * always identical to the source format.
190 */
191 if (code->index)
192 return -EINVAL;
193
194 format = v4l2_subdev_get_try_format(fh, UDS_PAD_SINK);
195 code->code = format->code;
196 }
197
198 return 0;
199 }
200
uds_enum_frame_size(struct v4l2_subdev * subdev,struct v4l2_subdev_fh * fh,struct v4l2_subdev_frame_size_enum * fse)201 static int uds_enum_frame_size(struct v4l2_subdev *subdev,
202 struct v4l2_subdev_fh *fh,
203 struct v4l2_subdev_frame_size_enum *fse)
204 {
205 struct v4l2_mbus_framefmt *format;
206
207 format = v4l2_subdev_get_try_format(fh, UDS_PAD_SINK);
208
209 if (fse->index || fse->code != format->code)
210 return -EINVAL;
211
212 if (fse->pad == UDS_PAD_SINK) {
213 fse->min_width = UDS_MIN_SIZE;
214 fse->max_width = UDS_MAX_SIZE;
215 fse->min_height = UDS_MIN_SIZE;
216 fse->max_height = UDS_MAX_SIZE;
217 } else {
218 uds_output_limits(format->width, &fse->min_width,
219 &fse->max_width);
220 uds_output_limits(format->height, &fse->min_height,
221 &fse->max_height);
222 }
223
224 return 0;
225 }
226
uds_get_format(struct v4l2_subdev * subdev,struct v4l2_subdev_fh * fh,struct v4l2_subdev_format * fmt)227 static int uds_get_format(struct v4l2_subdev *subdev, struct v4l2_subdev_fh *fh,
228 struct v4l2_subdev_format *fmt)
229 {
230 struct vsp1_uds *uds = to_uds(subdev);
231
232 fmt->format = *vsp1_entity_get_pad_format(&uds->entity, fh, fmt->pad,
233 fmt->which);
234
235 return 0;
236 }
237
uds_try_format(struct vsp1_uds * uds,struct v4l2_subdev_fh * fh,unsigned int pad,struct v4l2_mbus_framefmt * fmt,enum v4l2_subdev_format_whence which)238 static void uds_try_format(struct vsp1_uds *uds, struct v4l2_subdev_fh *fh,
239 unsigned int pad, struct v4l2_mbus_framefmt *fmt,
240 enum v4l2_subdev_format_whence which)
241 {
242 struct v4l2_mbus_framefmt *format;
243 unsigned int minimum;
244 unsigned int maximum;
245
246 switch (pad) {
247 case UDS_PAD_SINK:
248 /* Default to YUV if the requested format is not supported. */
249 if (fmt->code != V4L2_MBUS_FMT_ARGB8888_1X32 &&
250 fmt->code != V4L2_MBUS_FMT_AYUV8_1X32)
251 fmt->code = V4L2_MBUS_FMT_AYUV8_1X32;
252
253 fmt->width = clamp(fmt->width, UDS_MIN_SIZE, UDS_MAX_SIZE);
254 fmt->height = clamp(fmt->height, UDS_MIN_SIZE, UDS_MAX_SIZE);
255 break;
256
257 case UDS_PAD_SOURCE:
258 /* The UDS scales but can't perform format conversion. */
259 format = vsp1_entity_get_pad_format(&uds->entity, fh,
260 UDS_PAD_SINK, which);
261 fmt->code = format->code;
262
263 uds_output_limits(format->width, &minimum, &maximum);
264 fmt->width = clamp(fmt->width, minimum, maximum);
265 uds_output_limits(format->height, &minimum, &maximum);
266 fmt->height = clamp(fmt->height, minimum, maximum);
267 break;
268 }
269
270 fmt->field = V4L2_FIELD_NONE;
271 fmt->colorspace = V4L2_COLORSPACE_SRGB;
272 }
273
uds_set_format(struct v4l2_subdev * subdev,struct v4l2_subdev_fh * fh,struct v4l2_subdev_format * fmt)274 static int uds_set_format(struct v4l2_subdev *subdev, struct v4l2_subdev_fh *fh,
275 struct v4l2_subdev_format *fmt)
276 {
277 struct vsp1_uds *uds = to_uds(subdev);
278 struct v4l2_mbus_framefmt *format;
279
280 uds_try_format(uds, fh, fmt->pad, &fmt->format, fmt->which);
281
282 format = vsp1_entity_get_pad_format(&uds->entity, fh, fmt->pad,
283 fmt->which);
284 *format = fmt->format;
285
286 if (fmt->pad == UDS_PAD_SINK) {
287 /* Propagate the format to the source pad. */
288 format = vsp1_entity_get_pad_format(&uds->entity, fh,
289 UDS_PAD_SOURCE, fmt->which);
290 *format = fmt->format;
291
292 uds_try_format(uds, fh, UDS_PAD_SOURCE, format, fmt->which);
293 }
294
295 return 0;
296 }
297
298 /* -----------------------------------------------------------------------------
299 * V4L2 Subdevice Operations
300 */
301
302 static struct v4l2_subdev_video_ops uds_video_ops = {
303 .s_stream = uds_s_stream,
304 };
305
306 static struct v4l2_subdev_pad_ops uds_pad_ops = {
307 .enum_mbus_code = uds_enum_mbus_code,
308 .enum_frame_size = uds_enum_frame_size,
309 .get_fmt = uds_get_format,
310 .set_fmt = uds_set_format,
311 };
312
313 static struct v4l2_subdev_ops uds_ops = {
314 .video = &uds_video_ops,
315 .pad = &uds_pad_ops,
316 };
317
318 /* -----------------------------------------------------------------------------
319 * Initialization and Cleanup
320 */
321
vsp1_uds_create(struct vsp1_device * vsp1,unsigned int index)322 struct vsp1_uds *vsp1_uds_create(struct vsp1_device *vsp1, unsigned int index)
323 {
324 struct v4l2_subdev *subdev;
325 struct vsp1_uds *uds;
326 int ret;
327
328 uds = devm_kzalloc(vsp1->dev, sizeof(*uds), GFP_KERNEL);
329 if (uds == NULL)
330 return ERR_PTR(-ENOMEM);
331
332 uds->entity.type = VSP1_ENTITY_UDS;
333 uds->entity.index = index;
334
335 ret = vsp1_entity_init(vsp1, &uds->entity, 2);
336 if (ret < 0)
337 return ERR_PTR(ret);
338
339 /* Initialize the V4L2 subdev. */
340 subdev = &uds->entity.subdev;
341 v4l2_subdev_init(subdev, &uds_ops);
342
343 subdev->entity.ops = &vsp1_media_ops;
344 subdev->internal_ops = &vsp1_subdev_internal_ops;
345 snprintf(subdev->name, sizeof(subdev->name), "%s uds.%u",
346 dev_name(vsp1->dev), index);
347 v4l2_set_subdevdata(subdev, uds);
348 subdev->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
349
350 vsp1_entity_init_formats(subdev, NULL);
351
352 return uds;
353 }
354