hibmc_drm_dp.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2// Copyright (c) 2024 Hisilicon Limited.
  3
  4#include <linux/io.h>
  5
  6#include <drm/drm_probe_helper.h>
  7#include <drm/drm_simple_kms_helper.h>
  8#include <drm/drm_atomic_helper.h>
  9#include <drm/drm_modes.h>
 10#include <drm/drm_drv.h>
 11#include <drm/drm_edid.h>
 12
 13#include "hibmc_drm_drv.h"
 14#include "dp/dp_hw.h"
 15#include "dp/dp_comm.h"
 16#include "dp/dp_config.h"
 17
 18#define DP_MASKED_SINK_HPD_PLUG_INT	BIT(2)
 19
 20static int hibmc_dp_connector_get_modes(struct drm_connector *connector)
 21{
 22	const struct drm_edid *drm_edid;
 23	int count;
 24
 25	drm_edid = drm_edid_read(connector);
 26
 27	drm_edid_connector_update(connector, drm_edid);
 28
 29	count = drm_edid_connector_add_modes(connector);
 30
 31	drm_edid_free(drm_edid);
 32
 33	return count;
 34}
 35
 36static bool hibmc_dp_get_dpcd(struct hibmc_dp_dev *dp_dev)
 37{
 38	int ret;
 39
 40	ret = drm_dp_read_dpcd_caps(dp_dev->aux, dp_dev->dpcd);
 41	if (ret)
 42		return false;
 43
 44	dp_dev->is_branch = drm_dp_is_branch(dp_dev->dpcd);
 45
 46	ret = drm_dp_read_desc(dp_dev->aux, &dp_dev->desc, dp_dev->is_branch);
 47	if (ret)
 48		return false;
 49
 50	ret = drm_dp_read_downstream_info(dp_dev->aux, dp_dev->dpcd, dp_dev->downstream_ports);
 51	if (ret)
 52		return false;
 53
 54	return true;
 55}
 56
 57static int hibmc_dp_detect(struct drm_connector *connector,
 58			   struct drm_modeset_acquire_ctx *ctx, bool force)
 59{
 60	struct hibmc_dp *dp = to_hibmc_dp(connector);
 61	struct hibmc_dp_dev *dp_dev = dp->dp_dev;
 62	int ret;
 63
 64	if (dp->irq_status) {
 65		if (dp_dev->hpd_status != HIBMC_HPD_IN)
 66			return connector_status_disconnected;
 67	}
 68
 69	if (!hibmc_dp_get_dpcd(dp_dev))
 70		return connector_status_disconnected;
 71
 72	if (!dp_dev->is_branch)
 73		return connector_status_connected;
 74
 75	if (drm_dp_read_sink_count_cap(connector, dp_dev->dpcd, &dp_dev->desc) &&
 76	    dp_dev->downstream_ports[0] & DP_DS_PORT_HPD) {
 77		ret = drm_dp_read_sink_count(dp_dev->aux);
 78		if (ret > 0)
 79			return connector_status_connected;
 80	}
 81
 82	return connector_status_disconnected;
 83}
 84
 85static int hibmc_dp_mode_valid(struct drm_connector *connector,
 86			       const struct drm_display_mode *mode,
 87			       struct drm_modeset_acquire_ctx *ctx,
 88			       enum drm_mode_status *status)
 89{
 90	struct hibmc_dp *dp = to_hibmc_dp(connector);
 91	u64 cur_val, max_val;
 92
 93	/* check DP link BW */
 94	cur_val = (u64)mode->clock * HIBMC_DP_BPP;
 95	max_val = (u64)hibmc_dp_get_link_rate(dp) * DP_MODE_VALI_CAL * hibmc_dp_get_lanes(dp);
 96
 97	*status = cur_val > max_val ? MODE_CLOCK_HIGH : MODE_OK;
 98
 99	return 0;
100}
101
102static const struct drm_connector_helper_funcs hibmc_dp_conn_helper_funcs = {
103	.get_modes = hibmc_dp_connector_get_modes,
104	.detect_ctx = hibmc_dp_detect,
105	.mode_valid_ctx = hibmc_dp_mode_valid,
106};
107
108static int hibmc_dp_late_register(struct drm_connector *connector)
109{
110	struct hibmc_dp *dp = to_hibmc_dp(connector);
111
112	hibmc_dp_enable_int(dp);
113
114	return drm_dp_aux_register(&dp->aux);
115}
116
117static void hibmc_dp_early_unregister(struct drm_connector *connector)
118{
119	struct hibmc_dp *dp = to_hibmc_dp(connector);
120
121	drm_dp_aux_unregister(&dp->aux);
122
123	hibmc_dp_disable_int(dp);
124}
125
126static const struct drm_connector_funcs hibmc_dp_conn_funcs = {
127	.reset = drm_atomic_helper_connector_reset,
128	.fill_modes = drm_helper_probe_single_connector_modes,
129	.destroy = drm_connector_cleanup,
130	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
131	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
132	.late_register = hibmc_dp_late_register,
133	.early_unregister = hibmc_dp_early_unregister,
134	.debugfs_init = hibmc_debugfs_init,
135};
136
137static inline int hibmc_dp_prepare(struct hibmc_dp *dp, struct drm_display_mode *mode)
138{
139	int ret;
140
141	hibmc_dp_display_en(dp, false);
142
143	ret = hibmc_dp_mode_set(dp, mode);
144	if (ret)
145		drm_err(dp->drm_dev, "hibmc dp mode set failed: %d\n", ret);
146
147	return ret;
148}
149
150static void hibmc_dp_encoder_enable(struct drm_encoder *drm_encoder,
151				    struct drm_atomic_state *state)
152{
153	struct hibmc_dp *dp = container_of(drm_encoder, struct hibmc_dp, encoder);
154	struct drm_display_mode *mode = &drm_encoder->crtc->state->mode;
155
156	if (hibmc_dp_prepare(dp, mode))
157		return;
158
159	hibmc_dp_display_en(dp, true);
160}
161
162static void hibmc_dp_encoder_disable(struct drm_encoder *drm_encoder,
163				     struct drm_atomic_state *state)
164{
165	struct hibmc_dp *dp = container_of(drm_encoder, struct hibmc_dp, encoder);
166
167	hibmc_dp_display_en(dp, false);
168}
169
170static const struct drm_encoder_helper_funcs hibmc_dp_encoder_helper_funcs = {
171	.atomic_enable = hibmc_dp_encoder_enable,
172	.atomic_disable = hibmc_dp_encoder_disable,
173};
174
175irqreturn_t hibmc_dp_hpd_isr(int irq, void *arg)
176{
177	struct drm_device *dev = (struct drm_device *)arg;
178	struct hibmc_drm_private *priv = to_hibmc_drm_private(dev);
179	int idx, exp_status;
180
181	if (!drm_dev_enter(dev, &idx))
182		return -ENODEV;
183
184	if (priv->dp.irq_status & DP_MASKED_SINK_HPD_PLUG_INT) {
185		drm_dbg_dp(&priv->dev, "HPD IN isr occur!\n");
186		hibmc_dp_hpd_cfg(&priv->dp);
187		exp_status = HIBMC_HPD_IN;
188	} else {
189		drm_dbg_dp(&priv->dev, "HPD OUT isr occur!\n");
190		hibmc_dp_reset_link(&priv->dp);
191		exp_status = HIBMC_HPD_OUT;
192	}
193
194	if (hibmc_dp_check_hpd_status(&priv->dp, exp_status))
195		drm_connector_helper_hpd_irq_event(&priv->dp.connector);
196
197	drm_dev_exit(idx);
198
199	return IRQ_HANDLED;
200}
201
202int hibmc_dp_init(struct hibmc_drm_private *priv)
203{
204	struct drm_device *dev = &priv->dev;
205	struct drm_crtc *crtc = &priv->crtc;
206	struct hibmc_dp *dp = &priv->dp;
207	struct drm_connector *connector = &dp->connector;
208	struct drm_encoder *encoder = &dp->encoder;
209	int ret;
210
211	dp->mmio = priv->mmio;
212	dp->drm_dev = dev;
213
214	ret = hibmc_dp_hw_init(&priv->dp);
215	if (ret) {
216		drm_err(dev, "hibmc dp hw init failed: %d\n", ret);
217		return ret;
218	}
219
220	hibmc_dp_display_en(&priv->dp, false);
221
222	encoder->possible_crtcs = drm_crtc_mask(crtc);
223	ret = drmm_encoder_init(dev, encoder, NULL, DRM_MODE_ENCODER_TMDS, NULL);
224	if (ret) {
225		drm_err(dev, "init dp encoder failed: %d\n", ret);
226		return ret;
227	}
228
229	drm_encoder_helper_add(encoder, &hibmc_dp_encoder_helper_funcs);
230
231	ret = drm_connector_init_with_ddc(dev, connector, &hibmc_dp_conn_funcs,
232					  DRM_MODE_CONNECTOR_DisplayPort, &dp->aux.ddc);
233	if (ret) {
234		drm_err(dev, "init dp connector failed: %d\n", ret);
235		return ret;
236	}
237
238	drm_connector_helper_add(connector, &hibmc_dp_conn_helper_funcs);
239
240	drm_connector_attach_encoder(connector, encoder);
241
242	connector->polled = DRM_CONNECTOR_POLL_HPD;
243
244	return 0;
245}