1/*	$NetBSD: amdgpu_dm_mst_types.c,v 1.2 2021/12/18 23:45:00 riastradh Exp $	*/
2
3/*
4 * Copyright 2012-15 Advanced Micro Devices, Inc.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
23 *
24 * Authors: AMD
25 *
26 */
27
28#include <sys/cdefs.h>
29__KERNEL_RCSID(0, "$NetBSD: amdgpu_dm_mst_types.c,v 1.2 2021/12/18 23:45:00 riastradh Exp $");
30
31#include <linux/version.h>
32#include <drm/drm_atomic_helper.h>
33#include <drm/drm_dp_mst_helper.h>
34#include "dm_services.h"
35#include "amdgpu.h"
36#include "amdgpu_dm.h"
37#include "amdgpu_dm_mst_types.h"
38
39#include "dc.h"
40#include "dm_helpers.h"
41
42#include "dc_link_ddc.h"
43
44#include "i2caux_interface.h"
45#if defined(CONFIG_DEBUG_FS)
46#include "amdgpu_dm_debugfs.h"
47#endif
48
49
50#if defined(CONFIG_DRM_AMD_DC_DCN)
51#include "dc/dcn20/dcn20_resource.h"
52#endif
53
54/* #define TRACE_DPCD */
55
56#ifdef TRACE_DPCD
57#define SIDE_BAND_MSG(address) (address >= DP_SIDEBAND_MSG_DOWN_REQ_BASE && address < DP_SINK_COUNT_ESI)
58
59static inline char *side_band_msg_type_to_str(uint32_t address)
60{
61	static char str[10] = {0};
62
63	if (address < DP_SIDEBAND_MSG_UP_REP_BASE)
64		strcpy(str, "DOWN_REQ");
65	else if (address < DP_SIDEBAND_MSG_DOWN_REP_BASE)
66		strcpy(str, "UP_REP");
67	else if (address < DP_SIDEBAND_MSG_UP_REQ_BASE)
68		strcpy(str, "DOWN_REP");
69	else
70		strcpy(str, "UP_REQ");
71
72	return str;
73}
74
75static void log_dpcd(uint8_t type,
76		     uint32_t address,
77		     uint8_t *data,
78		     uint32_t size,
79		     bool res)
80{
81	DRM_DEBUG_KMS("Op: %s, addr: %04x, SideBand Msg: %s, Op res: %s\n",
82			(type == DP_AUX_NATIVE_READ) ||
83			(type == DP_AUX_I2C_READ) ?
84					"Read" : "Write",
85			address,
86			SIDE_BAND_MSG(address) ?
87					side_band_msg_type_to_str(address) : "Nop",
88			res ? "OK" : "Fail");
89
90	if (res) {
91		print_hex_dump(KERN_INFO, "Body: ", DUMP_PREFIX_NONE, 16, 1, data, size, false);
92	}
93}
94#endif
95
96static ssize_t dm_dp_aux_transfer(struct drm_dp_aux *aux,
97				  struct drm_dp_aux_msg *msg)
98{
99	ssize_t result = 0;
100	struct aux_payload payload;
101	enum aux_channel_operation_result operation_result;
102
103	if (WARN_ON(msg->size > 16))
104		return -E2BIG;
105
106	payload.address = msg->address;
107	payload.data = msg->buffer;
108	payload.length = msg->size;
109	payload.reply = &msg->reply;
110	payload.i2c_over_aux = (msg->request & DP_AUX_NATIVE_WRITE) == 0;
111	payload.write = (msg->request & DP_AUX_I2C_READ) == 0;
112	payload.mot = (msg->request & DP_AUX_I2C_MOT) != 0;
113	payload.defer_delay = 0;
114
115	result = dc_link_aux_transfer_raw(TO_DM_AUX(aux)->ddc_service, &payload,
116				      &operation_result);
117
118	if (payload.write)
119		result = msg->size;
120
121	if (result < 0)
122		switch (operation_result) {
123		case AUX_CHANNEL_OPERATION_SUCCEEDED:
124			break;
125		case AUX_CHANNEL_OPERATION_FAILED_HPD_DISCON:
126		case AUX_CHANNEL_OPERATION_FAILED_REASON_UNKNOWN:
127			result = -EIO;
128			break;
129		case AUX_CHANNEL_OPERATION_FAILED_INVALID_REPLY:
130		case AUX_CHANNEL_OPERATION_FAILED_ENGINE_ACQUIRE:
131			result = -EBUSY;
132			break;
133		case AUX_CHANNEL_OPERATION_FAILED_TIMEOUT:
134			result = -ETIMEDOUT;
135			break;
136		}
137
138	return result;
139}
140
141static void
142dm_dp_mst_connector_destroy(struct drm_connector *connector)
143{
144	struct amdgpu_dm_connector *amdgpu_dm_connector = to_amdgpu_dm_connector(connector);
145	struct amdgpu_encoder *amdgpu_encoder = amdgpu_dm_connector->mst_encoder;
146
147	kfree(amdgpu_dm_connector->edid);
148	amdgpu_dm_connector->edid = NULL;
149
150	drm_encoder_cleanup(&amdgpu_encoder->base);
151	kfree(amdgpu_encoder);
152	drm_connector_cleanup(connector);
153	drm_dp_mst_put_port_malloc(amdgpu_dm_connector->port);
154	kfree(amdgpu_dm_connector);
155}
156
157static int
158amdgpu_dm_mst_connector_late_register(struct drm_connector *connector)
159{
160	struct amdgpu_dm_connector *amdgpu_dm_connector =
161		to_amdgpu_dm_connector(connector);
162	struct drm_dp_mst_port *port = amdgpu_dm_connector->port;
163
164#if defined(CONFIG_DEBUG_FS)
165	connector_debugfs_init(amdgpu_dm_connector);
166	amdgpu_dm_connector->debugfs_dpcd_address = 0;
167	amdgpu_dm_connector->debugfs_dpcd_size = 0;
168#endif
169
170	return drm_dp_mst_connector_late_register(connector, port);
171}
172
173static void
174amdgpu_dm_mst_connector_early_unregister(struct drm_connector *connector)
175{
176	struct amdgpu_dm_connector *amdgpu_dm_connector =
177		to_amdgpu_dm_connector(connector);
178	struct drm_dp_mst_port *port = amdgpu_dm_connector->port;
179
180	drm_dp_mst_connector_early_unregister(connector, port);
181}
182
183static const struct drm_connector_funcs dm_dp_mst_connector_funcs = {
184	.fill_modes = drm_helper_probe_single_connector_modes,
185	.destroy = dm_dp_mst_connector_destroy,
186	.reset = amdgpu_dm_connector_funcs_reset,
187	.atomic_duplicate_state = amdgpu_dm_connector_atomic_duplicate_state,
188	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
189	.atomic_set_property = amdgpu_dm_connector_atomic_set_property,
190	.atomic_get_property = amdgpu_dm_connector_atomic_get_property,
191	.late_register = amdgpu_dm_mst_connector_late_register,
192	.early_unregister = amdgpu_dm_mst_connector_early_unregister,
193};
194
195#if defined(CONFIG_DRM_AMD_DC_DCN)
196static bool validate_dsc_caps_on_connector(struct amdgpu_dm_connector *aconnector)
197{
198	struct dc_sink *dc_sink = aconnector->dc_sink;
199	struct drm_dp_mst_port *port = aconnector->port;
200	u8 dsc_caps[16] = { 0 };
201
202	aconnector->dsc_aux = drm_dp_mst_dsc_aux_for_port(port);
203
204	if (!aconnector->dsc_aux)
205		return false;
206
207	if (drm_dp_dpcd_read(aconnector->dsc_aux, DP_DSC_SUPPORT, dsc_caps, 16) < 0)
208		return false;
209
210	if (!dc_dsc_parse_dsc_dpcd(aconnector->dc_link->ctx->dc,
211				   dsc_caps, NULL,
212				   &dc_sink->sink_dsc_caps.dsc_dec_caps))
213		return false;
214
215	return true;
216}
217#endif
218
219static int dm_dp_mst_get_modes(struct drm_connector *connector)
220{
221	struct amdgpu_dm_connector *aconnector = to_amdgpu_dm_connector(connector);
222	int ret = 0;
223
224	if (!aconnector)
225		return drm_add_edid_modes(connector, NULL);
226
227	if (!aconnector->edid) {
228		struct edid *edid;
229		edid = drm_dp_mst_get_edid(connector, &aconnector->mst_port->mst_mgr, aconnector->port);
230
231		if (!edid) {
232			drm_connector_update_edid_property(
233				&aconnector->base,
234				NULL);
235			return ret;
236		}
237
238		aconnector->edid = edid;
239	}
240
241	if (aconnector->dc_sink && aconnector->dc_sink->sink_signal == SIGNAL_TYPE_VIRTUAL) {
242		dc_sink_release(aconnector->dc_sink);
243		aconnector->dc_sink = NULL;
244	}
245
246	if (!aconnector->dc_sink) {
247		struct dc_sink *dc_sink;
248		struct dc_sink_init_data init_params = {
249				.link = aconnector->dc_link,
250				.sink_signal = SIGNAL_TYPE_DISPLAY_PORT_MST };
251		dc_sink = dc_link_add_remote_sink(
252			aconnector->dc_link,
253			(uint8_t *)aconnector->edid,
254			(aconnector->edid->extensions + 1) * EDID_LENGTH,
255			&init_params);
256
257		dc_sink->priv = aconnector;
258		/* dc_link_add_remote_sink returns a new reference */
259		aconnector->dc_sink = dc_sink;
260
261		if (aconnector->dc_sink) {
262			amdgpu_dm_update_freesync_caps(
263					connector, aconnector->edid);
264
265#if defined(CONFIG_DRM_AMD_DC_DCN)
266			if (!validate_dsc_caps_on_connector(aconnector))
267				memset(&aconnector->dc_sink->sink_dsc_caps,
268				       0, sizeof(aconnector->dc_sink->sink_dsc_caps));
269#endif
270		}
271	}
272
273	drm_connector_update_edid_property(
274					&aconnector->base, aconnector->edid);
275
276	ret = drm_add_edid_modes(connector, aconnector->edid);
277
278	return ret;
279}
280
281static struct drm_encoder *
282dm_mst_atomic_best_encoder(struct drm_connector *connector,
283			   struct drm_connector_state *connector_state)
284{
285	return &to_amdgpu_dm_connector(connector)->mst_encoder->base;
286}
287
288static int
289dm_dp_mst_detect(struct drm_connector *connector,
290		 struct drm_modeset_acquire_ctx *ctx, bool force)
291{
292	struct amdgpu_dm_connector *aconnector = to_amdgpu_dm_connector(connector);
293	struct amdgpu_dm_connector *master = aconnector->mst_port;
294
295	return drm_dp_mst_detect_port(connector, ctx, &master->mst_mgr,
296				      aconnector->port);
297}
298
299static int dm_dp_mst_atomic_check(struct drm_connector *connector,
300				struct drm_atomic_state *state)
301{
302	struct drm_connector_state *new_conn_state =
303			drm_atomic_get_new_connector_state(state, connector);
304	struct drm_connector_state *old_conn_state =
305			drm_atomic_get_old_connector_state(state, connector);
306	struct amdgpu_dm_connector *aconnector = to_amdgpu_dm_connector(connector);
307	struct drm_crtc_state *new_crtc_state;
308	struct drm_dp_mst_topology_mgr *mst_mgr;
309	struct drm_dp_mst_port *mst_port;
310
311	mst_port = aconnector->port;
312	mst_mgr = &aconnector->mst_port->mst_mgr;
313
314	if (!old_conn_state->crtc)
315		return 0;
316
317	if (new_conn_state->crtc) {
318		new_crtc_state = drm_atomic_get_new_crtc_state(state, new_conn_state->crtc);
319		if (!new_crtc_state ||
320		    !drm_atomic_crtc_needs_modeset(new_crtc_state) ||
321		    new_crtc_state->enable)
322			return 0;
323		}
324
325	return drm_dp_atomic_release_vcpi_slots(state,
326						mst_mgr,
327						mst_port);
328}
329
330static const struct drm_connector_helper_funcs dm_dp_mst_connector_helper_funcs = {
331	.get_modes = dm_dp_mst_get_modes,
332	.mode_valid = amdgpu_dm_connector_mode_valid,
333	.atomic_best_encoder = dm_mst_atomic_best_encoder,
334	.detect_ctx = dm_dp_mst_detect,
335	.atomic_check = dm_dp_mst_atomic_check,
336};
337
338static void amdgpu_dm_encoder_destroy(struct drm_encoder *encoder)
339{
340	drm_encoder_cleanup(encoder);
341	kfree(encoder);
342}
343
344static const struct drm_encoder_funcs amdgpu_dm_encoder_funcs = {
345	.destroy = amdgpu_dm_encoder_destroy,
346};
347
348static struct amdgpu_encoder *
349dm_dp_create_fake_mst_encoder(struct amdgpu_dm_connector *connector)
350{
351	struct drm_device *dev = connector->base.dev;
352	struct amdgpu_device *adev = dev->dev_private;
353	struct amdgpu_encoder *amdgpu_encoder;
354	struct drm_encoder *encoder;
355
356	amdgpu_encoder = kzalloc(sizeof(*amdgpu_encoder), GFP_KERNEL);
357	if (!amdgpu_encoder)
358		return NULL;
359
360	encoder = &amdgpu_encoder->base;
361	encoder->possible_crtcs = amdgpu_dm_get_encoder_crtc_mask(adev);
362
363	drm_encoder_init(
364		dev,
365		&amdgpu_encoder->base,
366		&amdgpu_dm_encoder_funcs,
367		DRM_MODE_ENCODER_DPMST,
368		NULL);
369
370	drm_encoder_helper_add(encoder, &amdgpu_dm_encoder_helper_funcs);
371
372	return amdgpu_encoder;
373}
374
375static struct drm_connector *
376dm_dp_add_mst_connector(struct drm_dp_mst_topology_mgr *mgr,
377			struct drm_dp_mst_port *port,
378			const char *pathprop)
379{
380	struct amdgpu_dm_connector *master = container_of(mgr, struct amdgpu_dm_connector, mst_mgr);
381	struct drm_device *dev = master->base.dev;
382	struct amdgpu_device *adev = dev->dev_private;
383	struct amdgpu_dm_connector *aconnector;
384	struct drm_connector *connector;
385
386	aconnector = kzalloc(sizeof(*aconnector), GFP_KERNEL);
387	if (!aconnector)
388		return NULL;
389
390	connector = &aconnector->base;
391	aconnector->port = port;
392	aconnector->mst_port = master;
393
394	if (drm_connector_init(
395		dev,
396		connector,
397		&dm_dp_mst_connector_funcs,
398		DRM_MODE_CONNECTOR_DisplayPort)) {
399		kfree(aconnector);
400		return NULL;
401	}
402	drm_connector_helper_add(connector, &dm_dp_mst_connector_helper_funcs);
403
404	amdgpu_dm_connector_init_helper(
405		&adev->dm,
406		aconnector,
407		DRM_MODE_CONNECTOR_DisplayPort,
408		master->dc_link,
409		master->connector_id);
410
411	aconnector->mst_encoder = dm_dp_create_fake_mst_encoder(master);
412	drm_connector_attach_encoder(&aconnector->base,
413				     &aconnector->mst_encoder->base);
414
415	drm_object_attach_property(
416		&connector->base,
417		dev->mode_config.path_property,
418		0);
419	drm_object_attach_property(
420		&connector->base,
421		dev->mode_config.tile_property,
422		0);
423
424	drm_connector_set_path_property(connector, pathprop);
425
426	/*
427	 * Initialize connector state before adding the connectror to drm and
428	 * framebuffer lists
429	 */
430	amdgpu_dm_connector_funcs_reset(connector);
431
432	DRM_INFO("DM_MST: added connector: %p [id: %d] [master: %p]\n",
433		 aconnector, connector->base.id, aconnector->mst_port);
434
435	drm_dp_mst_get_port_malloc(port);
436
437	DRM_DEBUG_KMS(":%d\n", connector->base.id);
438
439	return connector;
440}
441
442static void dm_dp_destroy_mst_connector(struct drm_dp_mst_topology_mgr *mgr,
443					struct drm_connector *connector)
444{
445	struct amdgpu_dm_connector *master = container_of(mgr, struct amdgpu_dm_connector, mst_mgr);
446	struct drm_device *dev = master->base.dev;
447	struct amdgpu_device *adev = dev->dev_private;
448	struct amdgpu_dm_connector *aconnector = to_amdgpu_dm_connector(connector);
449
450	DRM_INFO("DM_MST: Disabling connector: %p [id: %d] [master: %p]\n",
451		 aconnector, connector->base.id, aconnector->mst_port);
452
453	if (aconnector->dc_sink) {
454		amdgpu_dm_update_freesync_caps(connector, NULL);
455		dc_link_remove_remote_sink(aconnector->dc_link,
456					   aconnector->dc_sink);
457		dc_sink_release(aconnector->dc_sink);
458		aconnector->dc_sink = NULL;
459	}
460
461	drm_connector_unregister(connector);
462	if (adev->mode_info.rfbdev)
463		drm_fb_helper_remove_one_connector(&adev->mode_info.rfbdev->helper, connector);
464	drm_connector_put(connector);
465}
466
467static void dm_dp_mst_register_connector(struct drm_connector *connector)
468{
469	struct drm_device *dev = connector->dev;
470	struct amdgpu_device *adev = dev->dev_private;
471
472	if (adev->mode_info.rfbdev)
473		drm_fb_helper_add_one_connector(&adev->mode_info.rfbdev->helper, connector);
474	else
475		DRM_ERROR("adev->mode_info.rfbdev is NULL\n");
476
477	drm_connector_register(connector);
478}
479
480static const struct drm_dp_mst_topology_cbs dm_mst_cbs = {
481	.add_connector = dm_dp_add_mst_connector,
482	.destroy_connector = dm_dp_destroy_mst_connector,
483	.register_connector = dm_dp_mst_register_connector
484};
485
486void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm,
487				       struct amdgpu_dm_connector *aconnector)
488{
489	aconnector->dm_dp_aux.aux.name = "dmdc";
490	aconnector->dm_dp_aux.aux.dev = aconnector->base.kdev;
491	aconnector->dm_dp_aux.aux.transfer = dm_dp_aux_transfer;
492	aconnector->dm_dp_aux.ddc_service = aconnector->dc_link->ddc;
493
494	drm_dp_aux_register(&aconnector->dm_dp_aux.aux);
495	drm_dp_cec_register_connector(&aconnector->dm_dp_aux.aux,
496				      &aconnector->base);
497
498	if (aconnector->base.connector_type == DRM_MODE_CONNECTOR_eDP)
499		return;
500
501	aconnector->mst_mgr.cbs = &dm_mst_cbs;
502	drm_dp_mst_topology_mgr_init(
503		&aconnector->mst_mgr,
504		dm->adev->ddev,
505		&aconnector->dm_dp_aux.aux,
506		16,
507		4,
508		aconnector->connector_id);
509}
510
511int dm_mst_get_pbn_divider(struct dc_link *link)
512{
513	if (!link)
514		return 0;
515
516	return dc_link_bandwidth_kbps(link,
517			dc_link_get_link_cap(link)) / (8 * 1000 * 54);
518}
519
520#if defined(CONFIG_DRM_AMD_DC_DCN)
521
522struct dsc_mst_fairness_params {
523	struct dc_crtc_timing *timing;
524	struct dc_sink *sink;
525	struct dc_dsc_bw_range bw_range;
526	bool compression_possible;
527	struct drm_dp_mst_port *port;
528};
529
530struct dsc_mst_fairness_vars {
531	int pbn;
532	bool dsc_enabled;
533	int bpp_x16;
534};
535
536static int kbps_to_peak_pbn(int kbps)
537{
538	u64 peak_kbps = kbps;
539
540	peak_kbps *= 1006;
541	peak_kbps = div_u64(peak_kbps, 1000);
542	return (int) DIV64_U64_ROUND_UP(peak_kbps * 64, (54 * 8 * 1000));
543}
544
545static void set_dsc_configs_from_fairness_vars(struct dsc_mst_fairness_params *params,
546		struct dsc_mst_fairness_vars *vars,
547		int count)
548{
549	int i;
550
551	for (i = 0; i < count; i++) {
552		memset(&params[i].timing->dsc_cfg, 0, sizeof(params[i].timing->dsc_cfg));
553		if (vars[i].dsc_enabled && dc_dsc_compute_config(
554					params[i].sink->ctx->dc->res_pool->dscs[0],
555					&params[i].sink->sink_dsc_caps.dsc_dec_caps,
556					params[i].sink->ctx->dc->debug.dsc_min_slice_height_override,
557					0,
558					params[i].timing,
559					&params[i].timing->dsc_cfg)) {
560			params[i].timing->flags.DSC = 1;
561			params[i].timing->dsc_cfg.bits_per_pixel = vars[i].bpp_x16;
562		} else {
563			params[i].timing->flags.DSC = 0;
564		}
565	}
566}
567
568static int bpp_x16_from_pbn(struct dsc_mst_fairness_params param, int pbn)
569{
570	struct dc_dsc_config dsc_config;
571	u64 kbps;
572
573	kbps = div_u64((u64)pbn * 994 * 8 * 54, 64);
574	dc_dsc_compute_config(
575			param.sink->ctx->dc->res_pool->dscs[0],
576			&param.sink->sink_dsc_caps.dsc_dec_caps,
577			param.sink->ctx->dc->debug.dsc_min_slice_height_override,
578			(int) kbps, param.timing, &dsc_config);
579
580	return dsc_config.bits_per_pixel;
581}
582
583static void increase_dsc_bpp(struct drm_atomic_state *state,
584			     struct dc_link *dc_link,
585			     struct dsc_mst_fairness_params *params,
586			     struct dsc_mst_fairness_vars *vars,
587			     int count)
588{
589	int i;
590	bool bpp_increased[MAX_PIPES];
591	int initial_slack[MAX_PIPES];
592	int min_initial_slack;
593	int next_index;
594	int remaining_to_increase = 0;
595	int pbn_per_timeslot;
596	int link_timeslots_used;
597	int fair_pbn_alloc;
598
599	for (i = 0; i < count; i++) {
600		if (vars[i].dsc_enabled) {
601			initial_slack[i] = kbps_to_peak_pbn(params[i].bw_range.max_kbps) - vars[i].pbn;
602			bpp_increased[i] = false;
603			remaining_to_increase += 1;
604		} else {
605			initial_slack[i] = 0;
606			bpp_increased[i] = true;
607		}
608	}
609
610	pbn_per_timeslot = dc_link_bandwidth_kbps(dc_link,
611			dc_link_get_link_cap(dc_link)) / (8 * 1000 * 54);
612
613	while (remaining_to_increase) {
614		next_index = -1;
615		min_initial_slack = -1;
616		for (i = 0; i < count; i++) {
617			if (!bpp_increased[i]) {
618				if (min_initial_slack == -1 || min_initial_slack > initial_slack[i]) {
619					min_initial_slack = initial_slack[i];
620					next_index = i;
621				}
622			}
623		}
624
625		if (next_index == -1)
626			break;
627
628		link_timeslots_used = 0;
629
630		for (i = 0; i < count; i++)
631			link_timeslots_used += DIV_ROUND_UP(vars[i].pbn, pbn_per_timeslot);
632
633		fair_pbn_alloc = (63 - link_timeslots_used) / remaining_to_increase * pbn_per_timeslot;
634
635		if (initial_slack[next_index] > fair_pbn_alloc) {
636			vars[next_index].pbn += fair_pbn_alloc;
637			if (drm_dp_atomic_find_vcpi_slots(state,
638							  params[next_index].port->mgr,
639							  params[next_index].port,
640							  vars[next_index].pbn,
641							  dm_mst_get_pbn_divider(dc_link)) < 0)
642				return;
643			if (!drm_dp_mst_atomic_check(state)) {
644				vars[next_index].bpp_x16 = bpp_x16_from_pbn(params[next_index], vars[next_index].pbn);
645			} else {
646				vars[next_index].pbn -= fair_pbn_alloc;
647				if (drm_dp_atomic_find_vcpi_slots(state,
648								  params[next_index].port->mgr,
649								  params[next_index].port,
650								  vars[next_index].pbn,
651								  dm_mst_get_pbn_divider(dc_link)) < 0)
652					return;
653			}
654		} else {
655			vars[next_index].pbn += initial_slack[next_index];
656			if (drm_dp_atomic_find_vcpi_slots(state,
657							  params[next_index].port->mgr,
658							  params[next_index].port,
659							  vars[next_index].pbn,
660							  dm_mst_get_pbn_divider(dc_link)) < 0)
661				return;
662			if (!drm_dp_mst_atomic_check(state)) {
663				vars[next_index].bpp_x16 = params[next_index].bw_range.max_target_bpp_x16;
664			} else {
665				vars[next_index].pbn -= initial_slack[next_index];
666				if (drm_dp_atomic_find_vcpi_slots(state,
667								  params[next_index].port->mgr,
668								  params[next_index].port,
669								  vars[next_index].pbn,
670								  dm_mst_get_pbn_divider(dc_link)) < 0)
671					return;
672			}
673		}
674
675		bpp_increased[next_index] = true;
676		remaining_to_increase--;
677	}
678}
679
680static void try_disable_dsc(struct drm_atomic_state *state,
681			    struct dc_link *dc_link,
682			    struct dsc_mst_fairness_params *params,
683			    struct dsc_mst_fairness_vars *vars,
684			    int count)
685{
686	int i;
687	bool tried[MAX_PIPES];
688	int kbps_increase[MAX_PIPES];
689	int max_kbps_increase;
690	int next_index;
691	int remaining_to_try = 0;
692
693	for (i = 0; i < count; i++) {
694		if (vars[i].dsc_enabled && vars[i].bpp_x16 == params[i].bw_range.max_target_bpp_x16) {
695			kbps_increase[i] = params[i].bw_range.stream_kbps - params[i].bw_range.max_kbps;
696			tried[i] = false;
697			remaining_to_try += 1;
698		} else {
699			kbps_increase[i] = 0;
700			tried[i] = true;
701		}
702	}
703
704	while (remaining_to_try) {
705		next_index = -1;
706		max_kbps_increase = -1;
707		for (i = 0; i < count; i++) {
708			if (!tried[i]) {
709				if (max_kbps_increase == -1 || max_kbps_increase < kbps_increase[i]) {
710					max_kbps_increase = kbps_increase[i];
711					next_index = i;
712				}
713			}
714		}
715
716		if (next_index == -1)
717			break;
718
719		vars[next_index].pbn = kbps_to_peak_pbn(params[next_index].bw_range.stream_kbps);
720		if (drm_dp_atomic_find_vcpi_slots(state,
721						  params[next_index].port->mgr,
722						  params[next_index].port,
723						  vars[next_index].pbn,
724						  0) < 0)
725			return;
726
727		if (!drm_dp_mst_atomic_check(state)) {
728			vars[next_index].dsc_enabled = false;
729			vars[next_index].bpp_x16 = 0;
730		} else {
731			vars[next_index].pbn = kbps_to_peak_pbn(params[next_index].bw_range.max_kbps);
732			if (drm_dp_atomic_find_vcpi_slots(state,
733							  params[next_index].port->mgr,
734							  params[next_index].port,
735							  vars[next_index].pbn,
736							  dm_mst_get_pbn_divider(dc_link)) < 0)
737				return;
738		}
739
740		tried[next_index] = true;
741		remaining_to_try--;
742	}
743}
744
745static bool compute_mst_dsc_configs_for_link(struct drm_atomic_state *state,
746					     struct dc_state *dc_state,
747					     struct dc_link *dc_link)
748{
749	int i;
750	struct dc_stream_state *stream;
751	struct dsc_mst_fairness_params params[MAX_PIPES];
752	struct dsc_mst_fairness_vars vars[MAX_PIPES];
753	struct amdgpu_dm_connector *aconnector;
754	int count = 0;
755
756	memset(params, 0, sizeof(params));
757
758	/* Set up params */
759	for (i = 0; i < dc_state->stream_count; i++) {
760		struct dc_dsc_policy dsc_policy = {0};
761
762		stream = dc_state->streams[i];
763
764		if (stream->link != dc_link)
765			continue;
766
767		stream->timing.flags.DSC = 0;
768
769		params[count].timing = &stream->timing;
770		params[count].sink = stream->sink;
771		aconnector = (struct amdgpu_dm_connector *)stream->dm_stream_context;
772		params[count].port = aconnector->port;
773		params[count].compression_possible = stream->sink->sink_dsc_caps.dsc_dec_caps.is_dsc_supported;
774		dc_dsc_get_policy_for_timing(params[count].timing, &dsc_policy);
775		if (!dc_dsc_compute_bandwidth_range(
776				stream->sink->ctx->dc->res_pool->dscs[0],
777				stream->sink->ctx->dc->debug.dsc_min_slice_height_override,
778				dsc_policy.min_target_bpp,
779				dsc_policy.max_target_bpp,
780				&stream->sink->sink_dsc_caps.dsc_dec_caps,
781				&stream->timing, &params[count].bw_range))
782			params[count].bw_range.stream_kbps = dc_bandwidth_in_kbps_from_timing(&stream->timing);
783
784		count++;
785	}
786	/* Try no compression */
787	for (i = 0; i < count; i++) {
788		vars[i].pbn = kbps_to_peak_pbn(params[i].bw_range.stream_kbps);
789		vars[i].dsc_enabled = false;
790		vars[i].bpp_x16 = 0;
791		if (drm_dp_atomic_find_vcpi_slots(state,
792						 params[i].port->mgr,
793						 params[i].port,
794						 vars[i].pbn,
795						 0) < 0)
796			return false;
797	}
798	if (!drm_dp_mst_atomic_check(state)) {
799		set_dsc_configs_from_fairness_vars(params, vars, count);
800		return true;
801	}
802
803	/* Try max compression */
804	for (i = 0; i < count; i++) {
805		if (params[i].compression_possible) {
806			vars[i].pbn = kbps_to_peak_pbn(params[i].bw_range.min_kbps);
807			vars[i].dsc_enabled = true;
808			vars[i].bpp_x16 = params[i].bw_range.min_target_bpp_x16;
809			if (drm_dp_atomic_find_vcpi_slots(state,
810							  params[i].port->mgr,
811							  params[i].port,
812							  vars[i].pbn,
813							  dm_mst_get_pbn_divider(dc_link)) < 0)
814				return false;
815		} else {
816			vars[i].pbn = kbps_to_peak_pbn(params[i].bw_range.stream_kbps);
817			vars[i].dsc_enabled = false;
818			vars[i].bpp_x16 = 0;
819			if (drm_dp_atomic_find_vcpi_slots(state,
820							  params[i].port->mgr,
821							  params[i].port,
822							  vars[i].pbn,
823							  0) < 0)
824				return false;
825		}
826	}
827	if (drm_dp_mst_atomic_check(state))
828		return false;
829
830	/* Optimize degree of compression */
831	increase_dsc_bpp(state, dc_link, params, vars, count);
832
833	try_disable_dsc(state, dc_link, params, vars, count);
834
835	set_dsc_configs_from_fairness_vars(params, vars, count);
836
837	return true;
838}
839
840bool compute_mst_dsc_configs_for_state(struct drm_atomic_state *state,
841				       struct dc_state *dc_state)
842{
843	int i, j;
844	struct dc_stream_state *stream;
845	bool computed_streams[MAX_PIPES];
846	struct amdgpu_dm_connector *aconnector;
847
848	for (i = 0; i < dc_state->stream_count; i++)
849		computed_streams[i] = false;
850
851	for (i = 0; i < dc_state->stream_count; i++) {
852		stream = dc_state->streams[i];
853
854		if (stream->signal != SIGNAL_TYPE_DISPLAY_PORT_MST)
855			continue;
856
857		aconnector = (struct amdgpu_dm_connector *)stream->dm_stream_context;
858
859		if (!aconnector || !aconnector->dc_sink)
860			continue;
861
862		if (!aconnector->dc_sink->sink_dsc_caps.dsc_dec_caps.is_dsc_supported)
863			continue;
864
865		if (computed_streams[i])
866			continue;
867
868		mutex_lock(&aconnector->mst_mgr.lock);
869		if (!compute_mst_dsc_configs_for_link(state, dc_state, stream->link)) {
870			mutex_unlock(&aconnector->mst_mgr.lock);
871			return false;
872		}
873		mutex_unlock(&aconnector->mst_mgr.lock);
874
875		for (j = 0; j < dc_state->stream_count; j++) {
876			if (dc_state->streams[j]->link == stream->link)
877				computed_streams[j] = true;
878		}
879	}
880
881	for (i = 0; i < dc_state->stream_count; i++) {
882		stream = dc_state->streams[i];
883
884		if (stream->timing.flags.DSC == 1)
885			dcn20_add_dsc_to_stream_resource(stream->ctx->dc, dc_state, stream);
886	}
887
888	return true;
889}
890
891#endif
892