drm/msm: add PLL_ENABLE property to support clock recovery

PLL_ENABLE property is used to enable or disable the PLL
update function. With this property PLL update function
only works when PLL_ENABLE is set, and all changes done
to hardware will be discarded once PLL_ENABLE is cleared.

CRs-Fixed: 2042852
Change-Id: Ia321918382b8622101cff566049284810833f63e
Signed-off-by: Ray Zhang <rayz@codeaurora.org>

7 files changed, 198 insertions, 9 deletions

diff --git a/drivers/gpu/drm/msm/hdmi-staging/sde_hdmi.c b/drivers/gpu/drm/msm/hdmi-staging/sde_hdmi.c
index 64914585c9a5..d0c3deefabd7 100644
--- a/drivers/gpu/drm/msm/hdmi-staging/sde_hdmi.c
+++ b/drivers/gpu/drm/msm/hdmi-staging/sde_hdmi.c
@@ -705,13 +705,22 @@ static int _sde_hdmi_update_pll_delta(struct sde_hdmi *display, s32 ppm)
 	u64 clip_pclk;
 	int rc = 0;
 
+	mutex_lock(&display->display_lock);
+
 	if (!hdmi->power_on || !display->connected) {
 		SDE_ERROR("HDMI display is not ready\n");
+		mutex_unlock(&display->display_lock);
+		return -EINVAL;
+	}
+
+	if (!display->pll_update_enable) {
+		SDE_ERROR("PLL update function is not enabled\n");
+		mutex_unlock(&display->display_lock);
 		return -EINVAL;
 	}
 
 	/* get current pclk */
-	cur_pclk = hdmi->pixclock;
+	cur_pclk = hdmi->actual_pixclock;
 	/* get desired pclk */
 	dst_pclk = cur_pclk * (1000000000 + ppm);
 	do_div(dst_pclk, 1000000000);
@@ -725,13 +734,16 @@ static int _sde_hdmi_update_pll_delta(struct sde_hdmi *display, s32 ppm)
 
 		rc = clk_set_rate(hdmi->pwr_clks[0], clip_pclk);
 		if (rc < 0) {
-			SDE_ERROR("PLL update failed, reset clock rate\n");
+			SDE_ERROR("HDMI PLL update failed\n");
+			mutex_unlock(&display->display_lock);
 			return rc;
 		}
 
-		hdmi->pixclock = clip_pclk;
+		hdmi->actual_pixclock = clip_pclk;
 	}
 
+	mutex_unlock(&display->display_lock);
+
 	return rc;
 }
 
@@ -767,14 +779,119 @@ static const struct file_operations pll_delta_fops = {
 	.write = _sde_hdmi_debugfs_pll_delta_write,
 };
 
+/**
+ * _sde_hdmi_enable_pll_update() - Enable the HDMI PLL update function
+ *
+ * @enable: non-zero to enable PLL update function, 0 to disable.
+ * return: 0 on success, non-zero in case of failure.
+ *
+ */
+static int _sde_hdmi_enable_pll_update(struct sde_hdmi *display, s32 enable)
+{
+	struct hdmi *hdmi = display->ctrl.ctrl;
+	int rc = 0;
+
+	mutex_lock(&display->display_lock);
+
+	if (!hdmi->power_on || !display->connected) {
+		SDE_ERROR("HDMI display is not ready\n");
+		mutex_unlock(&display->display_lock);
+		return -EINVAL;
+	}
+
+	if (!enable && hdmi->actual_pixclock != hdmi->pixclock) {
+		/* reset pixel clock when disable */
+		rc = clk_set_rate(hdmi->pwr_clks[0], hdmi->pixclock);
+		if (rc < 0) {
+			SDE_ERROR("reset clock rate failed\n");
+			mutex_unlock(&display->display_lock);
+			return rc;
+		}
+	}
+	hdmi->actual_pixclock = hdmi->pixclock;
+
+	display->pll_update_enable = !!enable;
+
+	mutex_unlock(&display->display_lock);
+
+	SDE_DEBUG("HDMI PLL update: %s\n",
+			display->pll_update_enable ? "enable" : "disable");
+
+	return rc;
+}
+
+static ssize_t _sde_hdmi_debugfs_pll_enable_read(struct file *file,
+		char __user *buff, size_t count, loff_t *ppos)
+{
+	struct sde_hdmi *display = file->private_data;
+	char *buf;
+	u32 len = 0;
+
+	if (!display)
+		return -ENODEV;
+
+	if (*ppos)
+		return 0;
+
+	buf = kzalloc(SZ_1K, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	len += snprintf(buf, SZ_4K, "%s\n",
+			display->pll_update_enable ? "enable" : "disable");
+
+	if (copy_to_user(buff, buf, len)) {
+		kfree(buf);
+		return -EFAULT;
+	}
+
+	*ppos += len;
+
+	kfree(buf);
+	return len;
+}
+
+static ssize_t _sde_hdmi_debugfs_pll_enable_write(struct file *file,
+		const char __user *user_buf, size_t count, loff_t *ppos)
+{
+	struct sde_hdmi *display = file->private_data;
+	char buf[10];
+	int enable = 0;
+
+	if (!display)
+		return -ENODEV;
+
+	if (count >= sizeof(buf))
+		return -EFAULT;
+
+	if (copy_from_user(buf, user_buf, count))
+		return -EFAULT;
+
+	buf[count] = 0; /* end of string */
+
+	if (kstrtoint(buf, 0, &enable))
+		return -EFAULT;
+
+	_sde_hdmi_enable_pll_update(display, enable);
+
+	return count;
+}
+
+static const struct file_operations pll_enable_fops = {
+	.open = simple_open,
+	.read = _sde_hdmi_debugfs_pll_enable_read,
+	.write = _sde_hdmi_debugfs_pll_enable_write,
+};
+
 static int _sde_hdmi_debugfs_init(struct sde_hdmi *display)
 {
 	int rc = 0;
 	struct dentry *dir, *dump_file, *edid_modes;
 	struct dentry *edid_vsdb_info, *edid_hdr_info, *edid_hfvsdb_info;
-	struct dentry *edid_vcdb_info, *edid_vendor_name, *pll_file;
+	struct dentry *edid_vcdb_info, *edid_vendor_name;
 	struct dentry *src_hdcp14_support, *src_hdcp22_support;
 	struct dentry *sink_hdcp22_support, *hdmi_hdcp_state;
+	struct dentry *pll_delta_file, *pll_enable_file;
 
 	dir = debugfs_create_dir(display->name, NULL);
 	if (!dir) {
@@ -796,18 +913,30 @@ static int _sde_hdmi_debugfs_init(struct sde_hdmi *display)
 		goto error_remove_dir;
 	}
 
-	pll_file = debugfs_create_file("pll_delta",
+	pll_delta_file = debugfs_create_file("pll_delta",
 					0644,
 					dir,
 					display,
 					&pll_delta_fops);
-	if (IS_ERR_OR_NULL(pll_file)) {
-		rc = PTR_ERR(pll_file);
+	if (IS_ERR_OR_NULL(pll_delta_file)) {
+		rc = PTR_ERR(pll_delta_file);
 		SDE_ERROR("[%s]debugfs create pll_delta file failed, rc=%d\n",
 		       display->name, rc);
 		goto error_remove_dir;
 	}
 
+	pll_enable_file = debugfs_create_file("pll_enable",
+					0644,
+					dir,
+					display,
+					&pll_enable_fops);
+	if (IS_ERR_OR_NULL(pll_enable_file)) {
+		rc = PTR_ERR(pll_enable_file);
+		SDE_ERROR("[%s]debugfs create pll_enable file failed, rc=%d\n",
+		       display->name, rc);
+		goto error_remove_dir;
+	}
+
 	edid_modes = debugfs_create_file("edid_modes",
 					0444,
 					dir,
@@ -1749,17 +1878,42 @@ int sde_hdmi_set_property(struct drm_connector *connector,
 	if (!connector || !display) {
 		SDE_ERROR("connector=%pK or display=%pK is NULL\n",
 			connector, display);
-		return 0;
+		return -EINVAL;
 	}
 
 	SDE_DEBUG("\n");
 
-	if (property_index == CONNECTOR_PROP_PLL_DELTA)
+	if (property_index == CONNECTOR_PROP_PLL_ENABLE)
+		rc = _sde_hdmi_enable_pll_update(display, value);
+	else if (property_index == CONNECTOR_PROP_PLL_DELTA)
 		rc = _sde_hdmi_update_pll_delta(display, value);
 
 	return rc;
 }
 
+int sde_hdmi_get_property(struct drm_connector *connector,
+	struct drm_connector_state *state,
+	int property_index,
+	uint64_t *value,
+	void *display)
+{
+	struct sde_hdmi *hdmi_display = display;
+	int rc = 0;
+
+	if (!connector || !hdmi_display) {
+		SDE_ERROR("connector=%pK or display=%pK is NULL\n",
+			connector, hdmi_display);
+		return -EINVAL;
+	}
+
+	mutex_lock(&hdmi_display->display_lock);
+	if (property_index == CONNECTOR_PROP_PLL_ENABLE)
+		*value = hdmi_display->pll_update_enable ? 1 : 0;
+	mutex_unlock(&hdmi_display->display_lock);
+
+	return rc;
+}
+
 u32 sde_hdmi_get_num_of_displays(void)
 {
 	u32 count = 0;
diff --git a/drivers/gpu/drm/msm/hdmi-staging/sde_hdmi.h b/drivers/gpu/drm/msm/hdmi-staging/sde_hdmi.h
index 84d8720969be..47f440d617a3 100644
--- a/drivers/gpu/drm/msm/hdmi-staging/sde_hdmi.h
+++ b/drivers/gpu/drm/msm/hdmi-staging/sde_hdmi.h
@@ -109,6 +109,7 @@ enum hdmi_tx_feature_type {
  * @codec_ready:      If audio codec is ready.
  * @client_notify_pending: If there is client notification pending.
  * @irq_domain:       IRQ domain structure.
+ * @pll_update_enable: if it's allowed to update HDMI PLL ppm.
  * @notifier:         CEC notifider to convey physical address information.
  * @root:             Debug fs root entry.
  */
@@ -159,6 +160,7 @@ struct sde_hdmi {
 
 	struct irq_domain *irq_domain;
 	struct cec_notifier *notifier;
+	bool pll_update_enable;
 
 	struct delayed_work hdcp_cb_work;
 	struct dss_io_data io[HDMI_TX_MAX_IO];
@@ -345,6 +347,22 @@ int sde_hdmi_set_property(struct drm_connector *connector,
 			void *display);
 
 /**
+ * sde_hdmi_get_property() - get the connector properties
+ * @connector:        Handle to the connector.
+ * @state:            Handle to the connector state.
+ * @property_index:   property index.
+ * @value:            property value.
+ * @display:          Handle to the display.
+ *
+ * Return: error code.
+ */
+int sde_hdmi_get_property(struct drm_connector *connector,
+			struct drm_connector_state *state,
+			int property_index,
+			uint64_t *value,
+			void *display);
+
+/**
  * sde_hdmi_bridge_init() - init sde hdmi bridge
  * @hdmi:          Handle to the hdmi.
  *
diff --git a/drivers/gpu/drm/msm/hdmi-staging/sde_hdmi_bridge.c b/drivers/gpu/drm/msm/hdmi-staging/sde_hdmi_bridge.c
index 7af84f5c4229..24d2320683e4 100644
--- a/drivers/gpu/drm/msm/hdmi-staging/sde_hdmi_bridge.c
+++ b/drivers/gpu/drm/msm/hdmi-staging/sde_hdmi_bridge.c
@@ -494,6 +494,16 @@ static void _sde_hdmi_bridge_enable(struct drm_bridge *bridge)
 
 static void _sde_hdmi_bridge_disable(struct drm_bridge *bridge)
 {
+	struct sde_hdmi_bridge *sde_hdmi_bridge = to_hdmi_bridge(bridge);
+	struct hdmi *hdmi = sde_hdmi_bridge->hdmi;
+	struct sde_connector *c_conn = to_sde_connector(hdmi->connector);
+	struct sde_hdmi *display = (struct sde_hdmi *)c_conn->display;
+
+	mutex_lock(&display->display_lock);
+
+	display->pll_update_enable = false;
+
+	mutex_unlock(&display->display_lock);
 }
 
 static void _sde_hdmi_bridge_post_disable(struct drm_bridge *bridge)
diff --git a/drivers/gpu/drm/msm/hdmi/hdmi.h b/drivers/gpu/drm/msm/hdmi/hdmi.h
index 84b578eaad47..8ca7b36ee0c8 100644
--- a/drivers/gpu/drm/msm/hdmi/hdmi.h
+++ b/drivers/gpu/drm/msm/hdmi/hdmi.h
@@ -56,6 +56,7 @@ struct hdmi {
 	/* video state: */
 	bool power_on;
 	unsigned long int pixclock;
+	unsigned long int actual_pixclock;
 
 	void __iomem *mmio;
 	void __iomem *qfprom_mmio;
diff --git a/drivers/gpu/drm/msm/msm_drv.h b/drivers/gpu/drm/msm/msm_drv.h
index adc1e021b6f7..077caedbffa9 100644
--- a/drivers/gpu/drm/msm/msm_drv.h
+++ b/drivers/gpu/drm/msm/msm_drv.h
@@ -155,6 +155,7 @@ enum msm_mdp_conn_property {
 	CONNECTOR_PROP_DST_W,
 	CONNECTOR_PROP_DST_H,
 	CONNECTOR_PROP_PLL_DELTA,
+	CONNECTOR_PROP_PLL_ENABLE,
 
 	/* enum/bitmask properties */
 	CONNECTOR_PROP_TOPOLOGY_NAME,
diff --git a/drivers/gpu/drm/msm/sde/sde_connector.c b/drivers/gpu/drm/msm/sde/sde_connector.c
index 7538927a4993..e08fe210604c 100644
--- a/drivers/gpu/drm/msm/sde/sde_connector.c
+++ b/drivers/gpu/drm/msm/sde/sde_connector.c
@@ -582,6 +582,10 @@ struct drm_connector *sde_connector_init(struct drm_device *dev,
 			"PLL_DELTA", 0x0, INT_MIN, INT_MAX, 0,
 			CONNECTOR_PROP_PLL_DELTA);
 
+	msm_property_install_volatile_range(&c_conn->property_info,
+			"PLL_ENABLE", 0x0, 0, 1, 0,
+			CONNECTOR_PROP_PLL_ENABLE);
+
 	/* enum/bitmask properties */
 	msm_property_install_enum(&c_conn->property_info, "topology_name",
 			DRM_MODE_PROP_IMMUTABLE, 0, e_topology_name,
diff --git a/drivers/gpu/drm/msm/sde/sde_kms.c b/drivers/gpu/drm/msm/sde/sde_kms.c
index 45a87456e5ec..a240ed08da89 100644
--- a/drivers/gpu/drm/msm/sde/sde_kms.c
+++ b/drivers/gpu/drm/msm/sde/sde_kms.c
@@ -601,6 +601,7 @@ static int _sde_kms_setup_displays(struct drm_device *dev,
 		.mode_valid = sde_hdmi_mode_valid,
 		.get_info =   sde_hdmi_get_info,
 		.set_property = sde_hdmi_set_property,
+		.get_property = sde_hdmi_get_property,
 	};
 	struct msm_display_info info = {0};
 	struct drm_encoder *encoder;