1 files changed, 287 insertions, 0 deletions
diff --git a/drivers/gpu/drm/nouveau/nouveau_dp.c b/drivers/gpu/drm/nouveau/nouveau_dp.c
new file mode 100644
index 000000000..53185746f
--- /dev/null
+++ b/drivers/gpu/drm/nouveau/nouveau_dp.c
@@ -0,0 +1,287 @@
+/*
+ * Copyright 2009 Red Hat Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: Ben Skeggs
+ */
+
+#include <drm/display/drm_dp_helper.h>
+
+#include "nouveau_drv.h"
+#include "nouveau_connector.h"
+#include "nouveau_encoder.h"
+#include "nouveau_crtc.h"
+
+#include <nvif/class.h>
+#include <nvif/cl5070.h>
+
+MODULE_PARM_DESC(mst, "Enable DisplayPort multi-stream (default: enabled)");
+static int nouveau_mst = 1;
+module_param_named(mst, nouveau_mst, int, 0400);
+
+static bool
+nouveau_dp_has_sink_count(struct drm_connector *connector,
+			  struct nouveau_encoder *outp)
+{
+	return drm_dp_read_sink_count_cap(connector, outp->dp.dpcd, &outp->dp.desc);
+}
+
+static enum drm_connector_status
+nouveau_dp_probe_dpcd(struct nouveau_connector *nv_connector,
+		      struct nouveau_encoder *outp)
+{
+	struct drm_connector *connector = &nv_connector->base;
+	struct drm_dp_aux *aux = &nv_connector->aux;
+	struct nv50_mstm *mstm = NULL;
+	enum drm_connector_status status = connector_status_disconnected;
+	int ret;
+	u8 *dpcd = outp->dp.dpcd;
+
+	ret = drm_dp_read_dpcd_caps(aux, dpcd);
+	if (ret < 0)
+		goto out;
+
+	ret = drm_dp_read_desc(aux, &outp->dp.desc, drm_dp_is_branch(dpcd));
+	if (ret < 0)
+		goto out;
+
+	if (nouveau_mst) {
+		mstm = outp->dp.mstm;
+		if (mstm)
+			mstm->can_mst = drm_dp_read_mst_cap(aux, dpcd);
+	}
+
+	if (nouveau_dp_has_sink_count(connector, outp)) {
+		ret = drm_dp_read_sink_count(aux);
+		if (ret < 0)
+			goto out;
+
+		outp->dp.sink_count = ret;
+
+		/*
+		 * Dongle connected, but no display. Don't bother reading
+		 * downstream port info
+		 */
+		if (!outp->dp.sink_count)
+			return connector_status_disconnected;
+	}
+
+	ret = drm_dp_read_downstream_info(aux, dpcd,
+					  outp->dp.downstream_ports);
+	if (ret < 0)
+		goto out;
+
+	status = connector_status_connected;
+out:
+	if (status != connector_status_connected) {
+		/* Clear any cached info */
+		outp->dp.sink_count = 0;
+	}
+	return status;
+}
+
+int
+nouveau_dp_detect(struct nouveau_connector *nv_connector,
+		  struct nouveau_encoder *nv_encoder)
+{
+	struct drm_device *dev = nv_encoder->base.base.dev;
+	struct nouveau_drm *drm = nouveau_drm(dev);
+	struct drm_connector *connector = &nv_connector->base;
+	struct nv50_mstm *mstm = nv_encoder->dp.mstm;
+	enum drm_connector_status status;
+	u8 *dpcd = nv_encoder->dp.dpcd;
+	int ret = NOUVEAU_DP_NONE, hpd;
+
+	/* If we've already read the DPCD on an eDP device, we don't need to
+	 * reread it as it won't change
+	 */
+	if (connector->connector_type == DRM_MODE_CONNECTOR_eDP &&
+	    dpcd[DP_DPCD_REV] != 0)
+		return NOUVEAU_DP_SST;
+
+	mutex_lock(&nv_encoder->dp.hpd_irq_lock);
+	if (mstm) {
+		/* If we're not ready to handle MST state changes yet, just
+		 * report the last status of the connector. We'll reprobe it
+		 * once we've resumed.
+		 */
+		if (mstm->suspended) {
+			if (mstm->is_mst)
+				ret = NOUVEAU_DP_MST;
+			else if (connector->status ==
+				 connector_status_connected)
+				ret = NOUVEAU_DP_SST;
+
+			goto out;
+		}
+	}
+
+	/* Check status of HPD pin before attempting an AUX transaction that
+	 * would result in a number of (futile) retries on a connector which
+	 * has no display plugged.
+	 *
+	 * TODO: look into checking this before probing I2C to detect DVI/HDMI
+	 */
+	hpd = nvif_conn_hpd_status(&nv_connector->conn);
+	if (hpd == NVIF_CONN_HPD_STATUS_NOT_PRESENT)
+		goto out;
+
+	status = nouveau_dp_probe_dpcd(nv_connector, nv_encoder);
+	if (status == connector_status_disconnected)
+		goto out;
+
+	/* If we're in MST mode, we're done here */
+	if (mstm && mstm->can_mst && mstm->is_mst) {
+		ret = NOUVEAU_DP_MST;
+		goto out;
+	}
+
+	nv_encoder->dp.link_bw = 27000 * dpcd[DP_MAX_LINK_RATE];
+	nv_encoder->dp.link_nr =
+		dpcd[DP_MAX_LANE_COUNT] & DP_MAX_LANE_COUNT_MASK;
+
+	if (connector->connector_type == DRM_MODE_CONNECTOR_eDP && dpcd[DP_DPCD_REV] >= 0x13) {
+		struct drm_dp_aux *aux = &nv_connector->aux;
+		int ret, i;
+		u8 sink_rates[16];
+
+		ret = drm_dp_dpcd_read(aux, DP_SUPPORTED_LINK_RATES, sink_rates, sizeof(sink_rates));
+		if (ret == sizeof(sink_rates)) {
+			for (i = 0; i < ARRAY_SIZE(sink_rates); i += 2) {
+				int val = ((sink_rates[i + 1] << 8) | sink_rates[i]) * 200 / 10;
+				if (val && (i == 0 || val > nv_encoder->dp.link_bw))
+					nv_encoder->dp.link_bw = val;
+			}
+		}
+	}
+
+	NV_DEBUG(drm, "display: %dx%d dpcd 0x%02x\n",
+		 nv_encoder->dp.link_nr, nv_encoder->dp.link_bw,
+		 dpcd[DP_DPCD_REV]);
+	NV_DEBUG(drm, "encoder: %dx%d\n",
+		 nv_encoder->dcb->dpconf.link_nr,
+		 nv_encoder->dcb->dpconf.link_bw);
+
+	if (nv_encoder->dcb->dpconf.link_nr < nv_encoder->dp.link_nr)
+		nv_encoder->dp.link_nr = nv_encoder->dcb->dpconf.link_nr;
+	if (nv_encoder->dcb->dpconf.link_bw < nv_encoder->dp.link_bw)
+		nv_encoder->dp.link_bw = nv_encoder->dcb->dpconf.link_bw;
+
+	NV_DEBUG(drm, "maximum: %dx%d\n",
+		 nv_encoder->dp.link_nr, nv_encoder->dp.link_bw);
+
+	if (mstm && mstm->can_mst) {
+		ret = nv50_mstm_detect(nv_encoder);
+		if (ret == 1) {
+			ret = NOUVEAU_DP_MST;
+			goto out;
+		} else if (ret != 0) {
+			goto out;
+		}
+	}
+	ret = NOUVEAU_DP_SST;
+
+out:
+	if (mstm && !mstm->suspended && ret != NOUVEAU_DP_MST)
+		nv50_mstm_remove(mstm);
+
+	mutex_unlock(&nv_encoder->dp.hpd_irq_lock);
+	return ret;
+}
+
+void nouveau_dp_irq(struct nouveau_drm *drm,
+		    struct nouveau_connector *nv_connector)
+{
+	struct drm_connector *connector = &nv_connector->base;
+	struct nouveau_encoder *outp = find_encoder(connector, DCB_OUTPUT_DP);
+	struct nv50_mstm *mstm;
+	int ret;
+	bool send_hpd = false;
+
+	if (!outp)
+		return;
+
+	mstm = outp->dp.mstm;
+	NV_DEBUG(drm, "service %s\n", connector->name);
+
+	mutex_lock(&outp->dp.hpd_irq_lock);
+
+	if (mstm && mstm->is_mst) {
+		if (!nv50_mstm_service(drm, nv_connector, mstm))
+			send_hpd = true;
+	} else {
+		drm_dp_cec_irq(&nv_connector->aux);
+
+		if (nouveau_dp_has_sink_count(connector, outp)) {
+			ret = drm_dp_read_sink_count(&nv_connector->aux);
+			if (ret != outp->dp.sink_count)
+				send_hpd = true;
+			if (ret >= 0)
+				outp->dp.sink_count = ret;
+		}
+	}
+
+	mutex_unlock(&outp->dp.hpd_irq_lock);
+
+	if (send_hpd)
+		nouveau_connector_hpd(connector);
+}
+
+/* TODO:
+ * - Validate against the DP caps advertised by the GPU (we don't check these
+ *   yet)
+ */
+enum drm_mode_status
+nv50_dp_mode_valid(struct drm_connector *connector,
+		   struct nouveau_encoder *outp,
+		   const struct drm_display_mode *mode,
+		   unsigned *out_clock)
+{
+	const unsigned int min_clock = 25000;
+	unsigned int max_rate, mode_rate, ds_max_dotclock, clock = mode->clock;
+	/* Check with the minmum bpc always, so we can advertise better modes.
+	 * In particlar not doing this causes modes to be dropped on HDR
+	 * displays as we might check with a bpc of 16 even.
+	 */
+	const u8 bpp = 6 * 3;
+
+	if (mode->flags & DRM_MODE_FLAG_INTERLACE && !outp->caps.dp_interlace)
+		return MODE_NO_INTERLACE;
+
+	if ((mode->flags & DRM_MODE_FLAG_3D_MASK) == DRM_MODE_FLAG_3D_FRAME_PACKING)
+		clock *= 2;
+
+	max_rate = outp->dp.link_nr * outp->dp.link_bw;
+	mode_rate = DIV_ROUND_UP(clock * bpp, 8);
+	if (mode_rate > max_rate)
+		return MODE_CLOCK_HIGH;
+
+	ds_max_dotclock = drm_dp_downstream_max_dotclock(outp->dp.dpcd, outp->dp.downstream_ports);
+	if (ds_max_dotclock && clock > ds_max_dotclock)
+		return MODE_CLOCK_HIGH;
+
+	if (clock < min_clock)
+		return MODE_CLOCK_LOW;
+
+	if (out_clock)
+		*out_clock = clock;
+
+	return MODE_OK;
+}