1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2020 Intel Corporation
4  *
5  */
6 
7 #include "i915_drv.h"
8 #include "i915_reg.h"
9 #include "intel_de.h"
10 #include "intel_display_types.h"
11 #include "intel_vrr.h"
12 
13 bool intel_vrr_is_capable(struct intel_connector *connector)
14 {
15 	const struct drm_display_info *info = &connector->base.display_info;
16 	struct drm_i915_private *i915 = to_i915(connector->base.dev);
17 	struct intel_dp *intel_dp;
18 
19 	/*
20 	 * DP Sink is capable of VRR video timings if
21 	 * Ignore MSA bit is set in DPCD.
22 	 * EDID monitor range also should be atleast 10 for reasonable
23 	 * Adaptive Sync or Variable Refresh Rate end user experience.
24 	 */
25 	switch (connector->base.connector_type) {
26 	case DRM_MODE_CONNECTOR_eDP:
27 		if (!connector->panel.vbt.vrr)
28 			return false;
29 		fallthrough;
30 	case DRM_MODE_CONNECTOR_DisplayPort:
31 		intel_dp = intel_attached_dp(connector);
32 
33 		if (!drm_dp_sink_can_do_video_without_timing_msa(intel_dp->dpcd))
34 			return false;
35 
36 		break;
37 	default:
38 		return false;
39 	}
40 
41 	return HAS_VRR(i915) &&
42 		info->monitor_range.max_vfreq - info->monitor_range.min_vfreq > 10;
43 }
44 
45 void
46 intel_vrr_check_modeset(struct intel_atomic_state *state)
47 {
48 	int i;
49 	struct intel_crtc_state *old_crtc_state, *new_crtc_state;
50 	struct intel_crtc *crtc;
51 
52 	for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state,
53 					    new_crtc_state, i) {
54 		if (new_crtc_state->uapi.vrr_enabled !=
55 		    old_crtc_state->uapi.vrr_enabled)
56 			new_crtc_state->uapi.mode_changed = true;
57 	}
58 }
59 
60 /*
61  * Without VRR registers get latched at:
62  *  vblank_start
63  *
64  * With VRR the earliest registers can get latched is:
65  *  intel_vrr_vmin_vblank_start(), which if we want to maintain
66  *  the correct min vtotal is >=vblank_start+1
67  *
68  * The latest point registers can get latched is the vmax decision boundary:
69  *  intel_vrr_vmax_vblank_start()
70  *
71  * Between those two points the vblank exit starts (and hence registers get
72  * latched) ASAP after a push is sent.
73  *
74  * framestart_delay is programmable 1-4.
75  */
76 static int intel_vrr_vblank_exit_length(const struct intel_crtc_state *crtc_state)
77 {
78 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
79 	struct drm_i915_private *i915 = to_i915(crtc->base.dev);
80 
81 	if (DISPLAY_VER(i915) >= 13)
82 		return crtc_state->vrr.guardband;
83 	else
84 		/* The hw imposes the extra scanline before frame start */
85 		return crtc_state->vrr.pipeline_full + crtc_state->framestart_delay + 1;
86 }
87 
88 int intel_vrr_vmin_vblank_start(const struct intel_crtc_state *crtc_state)
89 {
90 	/* Min vblank actually determined by flipline that is always >=vmin+1 */
91 	return crtc_state->vrr.vmin + 1 - intel_vrr_vblank_exit_length(crtc_state);
92 }
93 
94 int intel_vrr_vmax_vblank_start(const struct intel_crtc_state *crtc_state)
95 {
96 	return crtc_state->vrr.vmax - intel_vrr_vblank_exit_length(crtc_state);
97 }
98 
99 void
100 intel_vrr_compute_config(struct intel_crtc_state *crtc_state,
101 			 struct drm_connector_state *conn_state)
102 {
103 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
104 	struct drm_i915_private *i915 = to_i915(crtc->base.dev);
105 	struct intel_connector *connector =
106 		to_intel_connector(conn_state->connector);
107 	struct drm_display_mode *adjusted_mode = &crtc_state->hw.adjusted_mode;
108 	const struct drm_display_info *info = &connector->base.display_info;
109 	int vmin, vmax;
110 
111 	if (!intel_vrr_is_capable(connector))
112 		return;
113 
114 	/*
115 	 * FIXME all joined pipes share the same transcoder.
116 	 * Need to account for that during VRR toggle/push/etc.
117 	 */
118 	if (crtc_state->bigjoiner_pipes)
119 		return;
120 
121 	if (adjusted_mode->flags & DRM_MODE_FLAG_INTERLACE)
122 		return;
123 
124 	vmin = DIV_ROUND_UP(adjusted_mode->crtc_clock * 1000,
125 			    adjusted_mode->crtc_htotal * info->monitor_range.max_vfreq);
126 	vmax = adjusted_mode->crtc_clock * 1000 /
127 		(adjusted_mode->crtc_htotal * info->monitor_range.min_vfreq);
128 
129 	vmin = max_t(int, vmin, adjusted_mode->crtc_vtotal);
130 	vmax = max_t(int, vmax, adjusted_mode->crtc_vtotal);
131 
132 	if (vmin >= vmax)
133 		return;
134 
135 	/*
136 	 * flipline determines the min vblank length the hardware will
137 	 * generate, and flipline>=vmin+1, hence we reduce vmin by one
138 	 * to make sure we can get the actual min vblank length.
139 	 */
140 	crtc_state->vrr.vmin = vmin - 1;
141 	crtc_state->vrr.vmax = vmax;
142 
143 	crtc_state->vrr.flipline = crtc_state->vrr.vmin + 1;
144 
145 	/*
146 	 * For XE_LPD+, we use guardband and pipeline override
147 	 * is deprecated.
148 	 */
149 	if (DISPLAY_VER(i915) >= 13) {
150 		crtc_state->vrr.guardband =
151 			crtc_state->vrr.vmin + 1 - adjusted_mode->crtc_vblank_start;
152 	} else {
153 		crtc_state->vrr.pipeline_full =
154 			min(255, crtc_state->vrr.vmin - adjusted_mode->crtc_vblank_start -
155 			    crtc_state->framestart_delay - 1);
156 	}
157 
158 	if (crtc_state->uapi.vrr_enabled) {
159 		crtc_state->vrr.enable = true;
160 		crtc_state->mode_flags |= I915_MODE_FLAG_VRR;
161 	}
162 }
163 
164 static u32 trans_vrr_ctl(const struct intel_crtc_state *crtc_state)
165 {
166 	struct drm_i915_private *i915 = to_i915(crtc_state->uapi.crtc->dev);
167 
168 	if (DISPLAY_VER(i915) >= 13)
169 		return VRR_CTL_IGN_MAX_SHIFT | VRR_CTL_FLIP_LINE_EN |
170 			XELPD_VRR_CTL_VRR_GUARDBAND(crtc_state->vrr.guardband);
171 	else
172 		return VRR_CTL_IGN_MAX_SHIFT | VRR_CTL_FLIP_LINE_EN |
173 			VRR_CTL_PIPELINE_FULL(crtc_state->vrr.pipeline_full) |
174 			VRR_CTL_PIPELINE_FULL_OVERRIDE;
175 }
176 
177 void intel_vrr_set_transcoder_timings(const struct intel_crtc_state *crtc_state)
178 {
179 	struct drm_i915_private *dev_priv = to_i915(crtc_state->uapi.crtc->dev);
180 	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
181 
182 	/*
183 	 * TRANS_SET_CONTEXT_LATENCY with VRR enabled
184 	 * requires this chicken bit on ADL/DG2.
185 	 */
186 	if (DISPLAY_VER(dev_priv) == 13)
187 		intel_de_rmw(dev_priv, CHICKEN_TRANS(cpu_transcoder),
188 			     0, PIPE_VBLANK_WITH_DELAY);
189 
190 	if (!crtc_state->vrr.flipline) {
191 		intel_de_write(dev_priv, TRANS_VRR_CTL(cpu_transcoder), 0);
192 		return;
193 	}
194 
195 	intel_de_write(dev_priv, TRANS_VRR_VMIN(cpu_transcoder), crtc_state->vrr.vmin - 1);
196 	intel_de_write(dev_priv, TRANS_VRR_VMAX(cpu_transcoder), crtc_state->vrr.vmax - 1);
197 	intel_de_write(dev_priv, TRANS_VRR_CTL(cpu_transcoder), trans_vrr_ctl(crtc_state));
198 	intel_de_write(dev_priv, TRANS_VRR_FLIPLINE(cpu_transcoder), crtc_state->vrr.flipline - 1);
199 }
200 
201 void intel_vrr_send_push(const struct intel_crtc_state *crtc_state)
202 {
203 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
204 	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
205 	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
206 
207 	if (!crtc_state->vrr.enable)
208 		return;
209 
210 	intel_de_write(dev_priv, TRANS_PUSH(cpu_transcoder),
211 		       TRANS_PUSH_EN | TRANS_PUSH_SEND);
212 }
213 
214 bool intel_vrr_is_push_sent(const struct intel_crtc_state *crtc_state)
215 {
216 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
217 	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
218 	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
219 
220 	if (!crtc_state->vrr.enable)
221 		return false;
222 
223 	return intel_de_read(dev_priv, TRANS_PUSH(cpu_transcoder)) & TRANS_PUSH_SEND;
224 }
225 
226 void intel_vrr_enable(const struct intel_crtc_state *crtc_state)
227 {
228 	struct drm_i915_private *dev_priv = to_i915(crtc_state->uapi.crtc->dev);
229 	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
230 
231 	if (!crtc_state->vrr.enable)
232 		return;
233 
234 	intel_de_write(dev_priv, TRANS_PUSH(cpu_transcoder), TRANS_PUSH_EN);
235 	intel_de_write(dev_priv, TRANS_VRR_CTL(cpu_transcoder),
236 		       VRR_CTL_VRR_ENABLE | trans_vrr_ctl(crtc_state));
237 }
238 
239 void intel_vrr_disable(const struct intel_crtc_state *old_crtc_state)
240 {
241 	struct intel_crtc *crtc = to_intel_crtc(old_crtc_state->uapi.crtc);
242 	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
243 	enum transcoder cpu_transcoder = old_crtc_state->cpu_transcoder;
244 
245 	if (!old_crtc_state->vrr.enable)
246 		return;
247 
248 	intel_de_write(dev_priv, TRANS_VRR_CTL(cpu_transcoder),
249 		       trans_vrr_ctl(old_crtc_state));
250 	intel_de_wait_for_clear(dev_priv, TRANS_VRR_STATUS(cpu_transcoder),
251 				VRR_STATUS_VRR_EN_LIVE, 1000);
252 	intel_de_write(dev_priv, TRANS_PUSH(cpu_transcoder), 0);
253 }
254 
255 void intel_vrr_get_config(struct intel_crtc_state *crtc_state)
256 {
257 	struct drm_i915_private *dev_priv = to_i915(crtc_state->uapi.crtc->dev);
258 	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
259 	u32 trans_vrr_ctl;
260 
261 	trans_vrr_ctl = intel_de_read(dev_priv, TRANS_VRR_CTL(cpu_transcoder));
262 
263 	crtc_state->vrr.enable = trans_vrr_ctl & VRR_CTL_VRR_ENABLE;
264 
265 	if (DISPLAY_VER(dev_priv) >= 13)
266 		crtc_state->vrr.guardband =
267 			REG_FIELD_GET(XELPD_VRR_CTL_VRR_GUARDBAND_MASK, trans_vrr_ctl);
268 	else
269 		if (trans_vrr_ctl & VRR_CTL_PIPELINE_FULL_OVERRIDE)
270 			crtc_state->vrr.pipeline_full =
271 				REG_FIELD_GET(VRR_CTL_PIPELINE_FULL_MASK, trans_vrr_ctl);
272 
273 	if (trans_vrr_ctl & VRR_CTL_FLIP_LINE_EN) {
274 		crtc_state->vrr.flipline = intel_de_read(dev_priv, TRANS_VRR_FLIPLINE(cpu_transcoder)) + 1;
275 		crtc_state->vrr.vmax = intel_de_read(dev_priv, TRANS_VRR_VMAX(cpu_transcoder)) + 1;
276 		crtc_state->vrr.vmin = intel_de_read(dev_priv, TRANS_VRR_VMIN(cpu_transcoder)) + 1;
277 	}
278 
279 	if (crtc_state->vrr.enable)
280 		crtc_state->mode_flags |= I915_MODE_FLAG_VRR;
281 }
282