1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * vsp1_uds.c  --  R-Car VSP1 Up and Down Scaler
4 *
5 * Copyright (C) 2013-2014 Renesas Electronics Corporation
6 *
7 * Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
8 */
9
10#include <linux/device.h>
11#include <linux/gfp.h>
12
13#include <media/v4l2-subdev.h>
14
15#include "vsp1.h"
16#include "vsp1_dl.h"
17#include "vsp1_pipe.h"
18#include "vsp1_uds.h"
19
20#define UDS_MIN_SIZE				4U
21#define UDS_MAX_SIZE				8190U
22
23#define UDS_MIN_FACTOR				0x0100
24#define UDS_MAX_FACTOR				0xffff
25
26/* -----------------------------------------------------------------------------
27 * Device Access
28 */
29
30static inline void vsp1_uds_write(struct vsp1_uds *uds,
31				  struct vsp1_dl_body *dlb, u32 reg, u32 data)
32{
33	vsp1_dl_body_write(dlb, reg + uds->entity.index * VI6_UDS_OFFSET, data);
34}
35
36/* -----------------------------------------------------------------------------
37 * Scaling Computation
38 */
39
40void vsp1_uds_set_alpha(struct vsp1_entity *entity, struct vsp1_dl_body *dlb,
41			unsigned int alpha)
42{
43	struct vsp1_uds *uds = to_uds(&entity->subdev);
44
45	vsp1_uds_write(uds, dlb, VI6_UDS_ALPVAL,
46		       alpha << VI6_UDS_ALPVAL_VAL0_SHIFT);
47}
48
49/*
50 * uds_output_size - Return the output size for an input size and scaling ratio
51 * @input: input size in pixels
52 * @ratio: scaling ratio in U4.12 fixed-point format
53 */
54static unsigned int uds_output_size(unsigned int input, unsigned int ratio)
55{
56	if (ratio > 4096) {
57		/* Down-scaling */
58		unsigned int mp;
59
60		mp = ratio / 4096;
61		mp = mp < 4 ? 1 : (mp < 8 ? 2 : 4);
62
63		return (input - 1) / mp * mp * 4096 / ratio + 1;
64	} else {
65		/* Up-scaling */
66		return (input - 1) * 4096 / ratio + 1;
67	}
68}
69
70/*
71 * uds_output_limits - Return the min and max output sizes for an input size
72 * @input: input size in pixels
73 * @minimum: minimum output size (returned)
74 * @maximum: maximum output size (returned)
75 */
76static void uds_output_limits(unsigned int input,
77			      unsigned int *minimum, unsigned int *maximum)
78{
79	*minimum = max(uds_output_size(input, UDS_MAX_FACTOR), UDS_MIN_SIZE);
80	*maximum = min(uds_output_size(input, UDS_MIN_FACTOR), UDS_MAX_SIZE);
81}
82
83/*
84 * uds_passband_width - Return the passband filter width for a scaling ratio
85 * @ratio: scaling ratio in U4.12 fixed-point format
86 */
87static unsigned int uds_passband_width(unsigned int ratio)
88{
89	if (ratio >= 4096) {
90		/* Down-scaling */
91		unsigned int mp;
92
93		mp = ratio / 4096;
94		mp = mp < 4 ? 1 : (mp < 8 ? 2 : 4);
95
96		return 64 * 4096 * mp / ratio;
97	} else {
98		/* Up-scaling */
99		return 64;
100	}
101}
102
103static unsigned int uds_compute_ratio(unsigned int input, unsigned int output)
104{
105	/* TODO: This is an approximation that will need to be refined. */
106	return (input - 1) * 4096 / (output - 1);
107}
108
109/* -----------------------------------------------------------------------------
110 * V4L2 Subdevice Pad Operations
111 */
112
113static int uds_enum_mbus_code(struct v4l2_subdev *subdev,
114			      struct v4l2_subdev_pad_config *cfg,
115			      struct v4l2_subdev_mbus_code_enum *code)
116{
117	static const unsigned int codes[] = {
118		MEDIA_BUS_FMT_ARGB8888_1X32,
119		MEDIA_BUS_FMT_AYUV8_1X32,
120	};
121
122	return vsp1_subdev_enum_mbus_code(subdev, cfg, code, codes,
123					  ARRAY_SIZE(codes));
124}
125
126static int uds_enum_frame_size(struct v4l2_subdev *subdev,
127			       struct v4l2_subdev_pad_config *cfg,
128			       struct v4l2_subdev_frame_size_enum *fse)
129{
130	struct vsp1_uds *uds = to_uds(subdev);
131	struct v4l2_subdev_pad_config *config;
132	struct v4l2_mbus_framefmt *format;
133	int ret = 0;
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	mutex_lock(&uds->entity.lock);
143
144	if (fse->index || fse->code != format->code) {
145		ret = -EINVAL;
146		goto done;
147	}
148
149	if (fse->pad == UDS_PAD_SINK) {
150		fse->min_width = UDS_MIN_SIZE;
151		fse->max_width = UDS_MAX_SIZE;
152		fse->min_height = UDS_MIN_SIZE;
153		fse->max_height = UDS_MAX_SIZE;
154	} else {
155		uds_output_limits(format->width, &fse->min_width,
156				  &fse->max_width);
157		uds_output_limits(format->height, &fse->min_height,
158				  &fse->max_height);
159	}
160
161done:
162	mutex_unlock(&uds->entity.lock);
163	return ret;
164}
165
166static void uds_try_format(struct vsp1_uds *uds,
167			   struct v4l2_subdev_pad_config *config,
168			   unsigned int pad, struct v4l2_mbus_framefmt *fmt)
169{
170	struct v4l2_mbus_framefmt *format;
171	unsigned int minimum;
172	unsigned int maximum;
173
174	switch (pad) {
175	case UDS_PAD_SINK:
176		/* Default to YUV if the requested format is not supported. */
177		if (fmt->code != MEDIA_BUS_FMT_ARGB8888_1X32 &&
178		    fmt->code != MEDIA_BUS_FMT_AYUV8_1X32)
179			fmt->code = MEDIA_BUS_FMT_AYUV8_1X32;
180
181		fmt->width = clamp(fmt->width, UDS_MIN_SIZE, UDS_MAX_SIZE);
182		fmt->height = clamp(fmt->height, UDS_MIN_SIZE, UDS_MAX_SIZE);
183		break;
184
185	case UDS_PAD_SOURCE:
186		/* The UDS scales but can't perform format conversion. */
187		format = vsp1_entity_get_pad_format(&uds->entity, config,
188						    UDS_PAD_SINK);
189		fmt->code = format->code;
190
191		uds_output_limits(format->width, &minimum, &maximum);
192		fmt->width = clamp(fmt->width, minimum, maximum);
193		uds_output_limits(format->height, &minimum, &maximum);
194		fmt->height = clamp(fmt->height, minimum, maximum);
195		break;
196	}
197
198	fmt->field = V4L2_FIELD_NONE;
199	fmt->colorspace = V4L2_COLORSPACE_SRGB;
200}
201
202static int uds_set_format(struct v4l2_subdev *subdev,
203			  struct v4l2_subdev_pad_config *cfg,
204			  struct v4l2_subdev_format *fmt)
205{
206	struct vsp1_uds *uds = to_uds(subdev);
207	struct v4l2_subdev_pad_config *config;
208	struct v4l2_mbus_framefmt *format;
209	int ret = 0;
210
211	mutex_lock(&uds->entity.lock);
212
213	config = vsp1_entity_get_pad_config(&uds->entity, cfg, fmt->which);
214	if (!config) {
215		ret = -EINVAL;
216		goto done;
217	}
218
219	uds_try_format(uds, config, fmt->pad, &fmt->format);
220
221	format = vsp1_entity_get_pad_format(&uds->entity, config, fmt->pad);
222	*format = fmt->format;
223
224	if (fmt->pad == UDS_PAD_SINK) {
225		/* Propagate the format to the source pad. */
226		format = vsp1_entity_get_pad_format(&uds->entity, config,
227						    UDS_PAD_SOURCE);
228		*format = fmt->format;
229
230		uds_try_format(uds, config, UDS_PAD_SOURCE, format);
231	}
232
233done:
234	mutex_unlock(&uds->entity.lock);
235	return ret;
236}
237
238/* -----------------------------------------------------------------------------
239 * V4L2 Subdevice Operations
240 */
241
242static const struct v4l2_subdev_pad_ops uds_pad_ops = {
243	.init_cfg = vsp1_entity_init_cfg,
244	.enum_mbus_code = uds_enum_mbus_code,
245	.enum_frame_size = uds_enum_frame_size,
246	.get_fmt = vsp1_subdev_get_pad_format,
247	.set_fmt = uds_set_format,
248};
249
250static const struct v4l2_subdev_ops uds_ops = {
251	.pad    = &uds_pad_ops,
252};
253
254/* -----------------------------------------------------------------------------
255 * VSP1 Entity Operations
256 */
257
258static void uds_configure_stream(struct vsp1_entity *entity,
259				 struct vsp1_pipeline *pipe,
260				 struct vsp1_dl_list *dl,
261				 struct vsp1_dl_body *dlb)
262{
263	struct vsp1_uds *uds = to_uds(&entity->subdev);
264	const struct v4l2_mbus_framefmt *output;
265	const struct v4l2_mbus_framefmt *input;
266	unsigned int hscale;
267	unsigned int vscale;
268	bool multitap;
269
270	input = vsp1_entity_get_pad_format(&uds->entity, uds->entity.config,
271					   UDS_PAD_SINK);
272	output = vsp1_entity_get_pad_format(&uds->entity, uds->entity.config,
273					    UDS_PAD_SOURCE);
274
275	hscale = uds_compute_ratio(input->width, output->width);
276	vscale = uds_compute_ratio(input->height, output->height);
277
278	dev_dbg(uds->entity.vsp1->dev, "hscale %u vscale %u\n", hscale, vscale);
279
280	/*
281	 * Multi-tap scaling can't be enabled along with alpha scaling when
282	 * scaling down with a factor lower than or equal to 1/2 in either
283	 * direction.
284	 */
285	if (uds->scale_alpha && (hscale >= 8192 || vscale >= 8192))
286		multitap = false;
287	else
288		multitap = true;
289
290	vsp1_uds_write(uds, dlb, VI6_UDS_CTRL,
291		       (uds->scale_alpha ? VI6_UDS_CTRL_AON : 0) |
292		       (multitap ? VI6_UDS_CTRL_BC : 0));
293
294	vsp1_uds_write(uds, dlb, VI6_UDS_PASS_BWIDTH,
295		       (uds_passband_width(hscale)
296				<< VI6_UDS_PASS_BWIDTH_H_SHIFT) |
297		       (uds_passband_width(vscale)
298				<< VI6_UDS_PASS_BWIDTH_V_SHIFT));
299
300	/* Set the scaling ratios. */
301	vsp1_uds_write(uds, dlb, VI6_UDS_SCALE,
302		       (hscale << VI6_UDS_SCALE_HFRAC_SHIFT) |
303		       (vscale << VI6_UDS_SCALE_VFRAC_SHIFT));
304}
305
306static void uds_configure_partition(struct vsp1_entity *entity,
307				    struct vsp1_pipeline *pipe,
308				    struct vsp1_dl_list *dl,
309				    struct vsp1_dl_body *dlb)
310{
311	struct vsp1_uds *uds = to_uds(&entity->subdev);
312	struct vsp1_partition *partition = pipe->partition;
313	const struct v4l2_mbus_framefmt *output;
314
315	output = vsp1_entity_get_pad_format(&uds->entity, uds->entity.config,
316					    UDS_PAD_SOURCE);
317
318	/* Input size clipping. */
319	vsp1_uds_write(uds, dlb, VI6_UDS_HSZCLIP, VI6_UDS_HSZCLIP_HCEN |
320		       (0 << VI6_UDS_HSZCLIP_HCL_OFST_SHIFT) |
321		       (partition->uds_sink.width
322				<< VI6_UDS_HSZCLIP_HCL_SIZE_SHIFT));
323
324	/* Output size clipping. */
325	vsp1_uds_write(uds, dlb, VI6_UDS_CLIP_SIZE,
326		       (partition->uds_source.width
327				<< VI6_UDS_CLIP_SIZE_HSIZE_SHIFT) |
328		       (output->height
329				<< VI6_UDS_CLIP_SIZE_VSIZE_SHIFT));
330}
331
332static unsigned int uds_max_width(struct vsp1_entity *entity,
333				  struct vsp1_pipeline *pipe)
334{
335	struct vsp1_uds *uds = to_uds(&entity->subdev);
336	const struct v4l2_mbus_framefmt *output;
337	const struct v4l2_mbus_framefmt *input;
338	unsigned int hscale;
339
340	input = vsp1_entity_get_pad_format(&uds->entity, uds->entity.config,
341					   UDS_PAD_SINK);
342	output = vsp1_entity_get_pad_format(&uds->entity, uds->entity.config,
343					    UDS_PAD_SOURCE);
344	hscale = output->width / input->width;
345
346	/*
347	 * The maximum width of the UDS is 304 pixels. These are input pixels
348	 * in the event of up-scaling, and output pixels in the event of
349	 * downscaling.
350	 *
351	 * To support overlapping partition windows we clamp at units of 256 and
352	 * the remaining pixels are reserved.
353	 */
354	if (hscale <= 2)
355		return 256;
356	else if (hscale <= 4)
357		return 512;
358	else if (hscale <= 8)
359		return 1024;
360	else
361		return 2048;
362}
363
364/* -----------------------------------------------------------------------------
365 * Partition Algorithm Support
366 */
367
368static void uds_partition(struct vsp1_entity *entity,
369			  struct vsp1_pipeline *pipe,
370			  struct vsp1_partition *partition,
371			  unsigned int partition_idx,
372			  struct vsp1_partition_window *window)
373{
374	struct vsp1_uds *uds = to_uds(&entity->subdev);
375	const struct v4l2_mbus_framefmt *output;
376	const struct v4l2_mbus_framefmt *input;
377
378	/* Initialise the partition state. */
379	partition->uds_sink = *window;
380	partition->uds_source = *window;
381
382	input = vsp1_entity_get_pad_format(&uds->entity, uds->entity.config,
383					   UDS_PAD_SINK);
384	output = vsp1_entity_get_pad_format(&uds->entity, uds->entity.config,
385					    UDS_PAD_SOURCE);
386
387	partition->uds_sink.width = window->width * input->width
388				  / output->width;
389	partition->uds_sink.left = window->left * input->width
390				 / output->width;
391
392	*window = partition->uds_sink;
393}
394
395static const struct vsp1_entity_operations uds_entity_ops = {
396	.configure_stream = uds_configure_stream,
397	.configure_partition = uds_configure_partition,
398	.max_width = uds_max_width,
399	.partition = uds_partition,
400};
401
402/* -----------------------------------------------------------------------------
403 * Initialization and Cleanup
404 */
405
406struct vsp1_uds *vsp1_uds_create(struct vsp1_device *vsp1, unsigned int index)
407{
408	struct vsp1_uds *uds;
409	char name[6];
410	int ret;
411
412	uds = devm_kzalloc(vsp1->dev, sizeof(*uds), GFP_KERNEL);
413	if (uds == NULL)
414		return ERR_PTR(-ENOMEM);
415
416	uds->entity.ops = &uds_entity_ops;
417	uds->entity.type = VSP1_ENTITY_UDS;
418	uds->entity.index = index;
419
420	sprintf(name, "uds.%u", index);
421	ret = vsp1_entity_init(vsp1, &uds->entity, name, 2, &uds_ops,
422			       MEDIA_ENT_F_PROC_VIDEO_SCALER);
423	if (ret < 0)
424		return ERR_PTR(ret);
425
426	return uds;
427}
428