drm/i915: move generic hotplug code into new intel_hotplug.c file
We have enough generic hotplug functions sprinkled all over i915_irq.c
to warrant moving them to a file of their own. This should further
underline the distinction between generic code in the new file and
platform specific hotplug and irq code that remains in i915_irq.c.
Add new intel_hpd_init_work to keep work functions static, and rename
get_port_from_pin to intel_hpd_pin_to_port while increasing its
visibility, but keep everything else the same.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_hotplug.c b/drivers/gpu/drm/i915/intel_hotplug.c
new file mode 100644
index 0000000..3c53aac
--- /dev/null
+++ b/drivers/gpu/drm/i915/intel_hotplug.c
@@ -0,0 +1,452 @@
+/*
+ * Copyright © 2015 Intel Corporation
+ *
+ * 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 (including the next
+ * paragraph) 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 AUTHORS OR COPYRIGHT HOLDERS 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.
+ */
+
+#include <linux/kernel.h>
+
+#include <drm/drmP.h>
+#include <drm/i915_drm.h>
+
+#include "i915_drv.h"
+#include "intel_drv.h"
+
+enum port intel_hpd_pin_to_port(enum hpd_pin pin)
+{
+ switch (pin) {
+ case HPD_PORT_B:
+ return PORT_B;
+ case HPD_PORT_C:
+ return PORT_C;
+ case HPD_PORT_D:
+ return PORT_D;
+ default:
+ return PORT_A; /* no hpd */
+ }
+}
+
+#define HPD_STORM_DETECT_PERIOD 1000
+#define HPD_STORM_THRESHOLD 5
+#define HPD_STORM_REENABLE_DELAY (2 * 60 * 1000)
+
+/**
+ * intel_hpd_irq_storm_detect - gather stats and detect HPD irq storm on a pin
+ * @dev_priv: private driver data pointer
+ * @pin: the pin to gather stats on
+ *
+ * Gather stats about HPD irqs from the specified @pin, and detect irq
+ * storms. Only the pin specific stats and state are changed, the caller is
+ * responsible for further action.
+ *
+ * @HPD_STORM_THRESHOLD irqs are allowed within @HPD_STORM_DETECT_PERIOD ms,
+ * otherwise it's considered an irq storm, and the irq state is set to
+ * @HPD_MARK_DISABLED.
+ *
+ * Return true if an irq storm was detected on @pin.
+ */
+static bool intel_hpd_irq_storm_detect(struct drm_i915_private *dev_priv,
+ enum hpd_pin pin)
+{
+ unsigned long start = dev_priv->hotplug.stats[pin].last_jiffies;
+ unsigned long end = start + msecs_to_jiffies(HPD_STORM_DETECT_PERIOD);
+ bool storm = false;
+
+ if (!time_in_range(jiffies, start, end)) {
+ dev_priv->hotplug.stats[pin].last_jiffies = jiffies;
+ dev_priv->hotplug.stats[pin].count = 0;
+ DRM_DEBUG_KMS("Received HPD interrupt on PIN %d - cnt: 0\n", pin);
+ } else if (dev_priv->hotplug.stats[pin].count > HPD_STORM_THRESHOLD) {
+ dev_priv->hotplug.stats[pin].state = HPD_MARK_DISABLED;
+ DRM_DEBUG_KMS("HPD interrupt storm detected on PIN %d\n", pin);
+ storm = true;
+ } else {
+ dev_priv->hotplug.stats[pin].count++;
+ DRM_DEBUG_KMS("Received HPD interrupt on PIN %d - cnt: %d\n", pin,
+ dev_priv->hotplug.stats[pin].count);
+ }
+
+ return storm;
+}
+
+static void intel_hpd_irq_storm_disable(struct drm_i915_private *dev_priv)
+{
+ struct drm_device *dev = dev_priv->dev;
+ struct drm_mode_config *mode_config = &dev->mode_config;
+ struct intel_connector *intel_connector;
+ struct intel_encoder *intel_encoder;
+ struct drm_connector *connector;
+ enum hpd_pin pin;
+ bool hpd_disabled = false;
+
+ assert_spin_locked(&dev_priv->irq_lock);
+
+ list_for_each_entry(connector, &mode_config->connector_list, head) {
+ if (connector->polled != DRM_CONNECTOR_POLL_HPD)
+ continue;
+
+ intel_connector = to_intel_connector(connector);
+ intel_encoder = intel_connector->encoder;
+ if (!intel_encoder)
+ continue;
+
+ pin = intel_encoder->hpd_pin;
+ if (pin == HPD_NONE ||
+ dev_priv->hotplug.stats[pin].state != HPD_MARK_DISABLED)
+ continue;
+
+ DRM_INFO("HPD interrupt storm detected on connector %s: "
+ "switching from hotplug detection to polling\n",
+ connector->name);
+
+ dev_priv->hotplug.stats[pin].state = HPD_DISABLED;
+ connector->polled = DRM_CONNECTOR_POLL_CONNECT
+ | DRM_CONNECTOR_POLL_DISCONNECT;
+ hpd_disabled = true;
+ }
+
+ /* Enable polling and queue hotplug re-enabling. */
+ if (hpd_disabled) {
+ drm_kms_helper_poll_enable(dev);
+ mod_delayed_work(system_wq, &dev_priv->hotplug.reenable_work,
+ msecs_to_jiffies(HPD_STORM_REENABLE_DELAY));
+ }
+}
+
+static void intel_hpd_irq_storm_reenable_work(struct work_struct *work)
+{
+ struct drm_i915_private *dev_priv =
+ container_of(work, typeof(*dev_priv),
+ hotplug.reenable_work.work);
+ struct drm_device *dev = dev_priv->dev;
+ struct drm_mode_config *mode_config = &dev->mode_config;
+ int i;
+
+ intel_runtime_pm_get(dev_priv);
+
+ spin_lock_irq(&dev_priv->irq_lock);
+ for_each_hpd_pin(i) {
+ struct drm_connector *connector;
+
+ if (dev_priv->hotplug.stats[i].state != HPD_DISABLED)
+ continue;
+
+ dev_priv->hotplug.stats[i].state = HPD_ENABLED;
+
+ list_for_each_entry(connector, &mode_config->connector_list, head) {
+ struct intel_connector *intel_connector = to_intel_connector(connector);
+
+ if (intel_connector->encoder->hpd_pin == i) {
+ if (connector->polled != intel_connector->polled)
+ DRM_DEBUG_DRIVER("Reenabling HPD on connector %s\n",
+ connector->name);
+ connector->polled = intel_connector->polled;
+ if (!connector->polled)
+ connector->polled = DRM_CONNECTOR_POLL_HPD;
+ }
+ }
+ }
+ if (dev_priv->display.hpd_irq_setup)
+ dev_priv->display.hpd_irq_setup(dev);
+ spin_unlock_irq(&dev_priv->irq_lock);
+
+ intel_runtime_pm_put(dev_priv);
+}
+
+static bool intel_hpd_irq_event(struct drm_device *dev,
+ struct drm_connector *connector)
+{
+ enum drm_connector_status old_status;
+
+ WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
+ old_status = connector->status;
+
+ connector->status = connector->funcs->detect(connector, false);
+ if (old_status == connector->status)
+ return false;
+
+ DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n",
+ connector->base.id,
+ connector->name,
+ drm_get_connector_status_name(old_status),
+ drm_get_connector_status_name(connector->status));
+
+ return true;
+}
+
+static void i915_digport_work_func(struct work_struct *work)
+{
+ struct drm_i915_private *dev_priv =
+ container_of(work, struct drm_i915_private, hotplug.dig_port_work);
+ u32 long_port_mask, short_port_mask;
+ struct intel_digital_port *intel_dig_port;
+ int i;
+ u32 old_bits = 0;
+
+ spin_lock_irq(&dev_priv->irq_lock);
+ long_port_mask = dev_priv->hotplug.long_port_mask;
+ dev_priv->hotplug.long_port_mask = 0;
+ short_port_mask = dev_priv->hotplug.short_port_mask;
+ dev_priv->hotplug.short_port_mask = 0;
+ spin_unlock_irq(&dev_priv->irq_lock);
+
+ for (i = 0; i < I915_MAX_PORTS; i++) {
+ bool valid = false;
+ bool long_hpd = false;
+ intel_dig_port = dev_priv->hotplug.irq_port[i];
+ if (!intel_dig_port || !intel_dig_port->hpd_pulse)
+ continue;
+
+ if (long_port_mask & (1 << i)) {
+ valid = true;
+ long_hpd = true;
+ } else if (short_port_mask & (1 << i))
+ valid = true;
+
+ if (valid) {
+ enum irqreturn ret;
+
+ ret = intel_dig_port->hpd_pulse(intel_dig_port, long_hpd);
+ if (ret == IRQ_NONE) {
+ /* fall back to old school hpd */
+ old_bits |= (1 << intel_dig_port->base.hpd_pin);
+ }
+ }
+ }
+
+ if (old_bits) {
+ spin_lock_irq(&dev_priv->irq_lock);
+ dev_priv->hotplug.event_bits |= old_bits;
+ spin_unlock_irq(&dev_priv->irq_lock);
+ schedule_work(&dev_priv->hotplug.hotplug_work);
+ }
+}
+
+/*
+ * Handle hotplug events outside the interrupt handler proper.
+ */
+static void i915_hotplug_work_func(struct work_struct *work)
+{
+ struct drm_i915_private *dev_priv =
+ container_of(work, struct drm_i915_private, hotplug.hotplug_work);
+ struct drm_device *dev = dev_priv->dev;
+ struct drm_mode_config *mode_config = &dev->mode_config;
+ struct intel_connector *intel_connector;
+ struct intel_encoder *intel_encoder;
+ struct drm_connector *connector;
+ bool changed = false;
+ u32 hpd_event_bits;
+
+ mutex_lock(&mode_config->mutex);
+ DRM_DEBUG_KMS("running encoder hotplug functions\n");
+
+ spin_lock_irq(&dev_priv->irq_lock);
+
+ hpd_event_bits = dev_priv->hotplug.event_bits;
+ dev_priv->hotplug.event_bits = 0;
+
+ /* Disable hotplug on connectors that hit an irq storm. */
+ intel_hpd_irq_storm_disable(dev_priv);
+
+ spin_unlock_irq(&dev_priv->irq_lock);
+
+ list_for_each_entry(connector, &mode_config->connector_list, head) {
+ intel_connector = to_intel_connector(connector);
+ if (!intel_connector->encoder)
+ continue;
+ intel_encoder = intel_connector->encoder;
+ if (hpd_event_bits & (1 << intel_encoder->hpd_pin)) {
+ DRM_DEBUG_KMS("Connector %s (pin %i) received hotplug event.\n",
+ connector->name, intel_encoder->hpd_pin);
+ if (intel_encoder->hot_plug)
+ intel_encoder->hot_plug(intel_encoder);
+ if (intel_hpd_irq_event(dev, connector))
+ changed = true;
+ }
+ }
+ mutex_unlock(&mode_config->mutex);
+
+ if (changed)
+ drm_kms_helper_hotplug_event(dev);
+}
+
+
+/**
+ * intel_hpd_irq_handler - main hotplug irq handler
+ * @dev: drm device
+ * @pin_mask: a mask of hpd pins that have triggered the irq
+ * @long_mask: a mask of hpd pins that may be long hpd pulses
+ *
+ * This is the main hotplug irq handler for all platforms. The platform specific
+ * irq handlers call the platform specific hotplug irq handlers, which read and
+ * decode the appropriate registers into bitmasks about hpd pins that have
+ * triggered (@pin_mask), and which of those pins may be long pulses
+ * (@long_mask). The @long_mask is ignored if the port corresponding to the pin
+ * is not a digital port.
+ *
+ * Here, we do hotplug irq storm detection and mitigation, and pass further
+ * processing to appropriate bottom halves.
+ */
+void intel_hpd_irq_handler(struct drm_device *dev,
+ u32 pin_mask, u32 long_mask)
+{
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ int i;
+ enum port port;
+ bool storm_detected = false;
+ bool queue_dig = false, queue_hp = false;
+ bool is_dig_port;
+
+ if (!pin_mask)
+ return;
+
+ spin_lock(&dev_priv->irq_lock);
+ for_each_hpd_pin(i) {
+ if (!(BIT(i) & pin_mask))
+ continue;
+
+ port = intel_hpd_pin_to_port(i);
+ is_dig_port = port && dev_priv->hotplug.irq_port[port];
+
+ if (is_dig_port) {
+ bool long_hpd = long_mask & BIT(i);
+
+ DRM_DEBUG_DRIVER("digital hpd port %c - %s\n", port_name(port),
+ long_hpd ? "long" : "short");
+ /*
+ * For long HPD pulses we want to have the digital queue happen,
+ * but we still want HPD storm detection to function.
+ */
+ queue_dig = true;
+ if (long_hpd) {
+ dev_priv->hotplug.long_port_mask |= (1 << port);
+ } else {
+ /* for short HPD just trigger the digital queue */
+ dev_priv->hotplug.short_port_mask |= (1 << port);
+ continue;
+ }
+ }
+
+ if (dev_priv->hotplug.stats[i].state == HPD_DISABLED) {
+ /*
+ * On GMCH platforms the interrupt mask bits only
+ * prevent irq generation, not the setting of the
+ * hotplug bits itself. So only WARN about unexpected
+ * interrupts on saner platforms.
+ */
+ WARN_ONCE(INTEL_INFO(dev)->gen >= 5 && !IS_VALLEYVIEW(dev),
+ "Received HPD interrupt on pin %d although disabled\n", i);
+ continue;
+ }
+
+ if (dev_priv->hotplug.stats[i].state != HPD_ENABLED)
+ continue;
+
+ if (!is_dig_port) {
+ dev_priv->hotplug.event_bits |= BIT(i);
+ queue_hp = true;
+ }
+
+ if (intel_hpd_irq_storm_detect(dev_priv, i)) {
+ dev_priv->hotplug.event_bits &= ~BIT(i);
+ storm_detected = true;
+ }
+ }
+
+ if (storm_detected)
+ dev_priv->display.hpd_irq_setup(dev);
+ spin_unlock(&dev_priv->irq_lock);
+
+ /*
+ * Our hotplug handler can grab modeset locks (by calling down into the
+ * fb helpers). Hence it must not be run on our own dev-priv->wq work
+ * queue for otherwise the flush_work in the pageflip code will
+ * deadlock.
+ */
+ if (queue_dig)
+ queue_work(dev_priv->hotplug.dp_wq, &dev_priv->hotplug.dig_port_work);
+ if (queue_hp)
+ schedule_work(&dev_priv->hotplug.hotplug_work);
+}
+
+/**
+ * intel_hpd_init - initializes and enables hpd support
+ * @dev_priv: i915 device instance
+ *
+ * This function enables the hotplug support. It requires that interrupts have
+ * already been enabled with intel_irq_init_hw(). From this point on hotplug and
+ * poll request can run concurrently to other code, so locking rules must be
+ * obeyed.
+ *
+ * This is a separate step from interrupt enabling to simplify the locking rules
+ * in the driver load and resume code.
+ */
+void intel_hpd_init(struct drm_i915_private *dev_priv)
+{
+ struct drm_device *dev = dev_priv->dev;
+ struct drm_mode_config *mode_config = &dev->mode_config;
+ struct drm_connector *connector;
+ int i;
+
+ for_each_hpd_pin(i) {
+ dev_priv->hotplug.stats[i].count = 0;
+ dev_priv->hotplug.stats[i].state = HPD_ENABLED;
+ }
+ list_for_each_entry(connector, &mode_config->connector_list, head) {
+ struct intel_connector *intel_connector = to_intel_connector(connector);
+ connector->polled = intel_connector->polled;
+ if (connector->encoder && !connector->polled && I915_HAS_HOTPLUG(dev) && intel_connector->encoder->hpd_pin > HPD_NONE)
+ connector->polled = DRM_CONNECTOR_POLL_HPD;
+ if (intel_connector->mst_port)
+ connector->polled = DRM_CONNECTOR_POLL_HPD;
+ }
+
+ /*
+ * Interrupt setup is already guaranteed to be single-threaded, this is
+ * just to make the assert_spin_locked checks happy.
+ */
+ spin_lock_irq(&dev_priv->irq_lock);
+ if (dev_priv->display.hpd_irq_setup)
+ dev_priv->display.hpd_irq_setup(dev);
+ spin_unlock_irq(&dev_priv->irq_lock);
+}
+
+void intel_hpd_init_work(struct drm_i915_private *dev_priv)
+{
+ INIT_WORK(&dev_priv->hotplug.hotplug_work, i915_hotplug_work_func);
+ INIT_WORK(&dev_priv->hotplug.dig_port_work, i915_digport_work_func);
+ INIT_DELAYED_WORK(&dev_priv->hotplug.reenable_work,
+ intel_hpd_irq_storm_reenable_work);
+}
+
+void intel_hpd_cancel_work(struct drm_i915_private *dev_priv)
+{
+ spin_lock_irq(&dev_priv->irq_lock);
+
+ dev_priv->hotplug.long_port_mask = 0;
+ dev_priv->hotplug.short_port_mask = 0;
+ dev_priv->hotplug.event_bits = 0;
+
+ spin_unlock_irq(&dev_priv->irq_lock);
+
+ cancel_work_sync(&dev_priv->hotplug.dig_port_work);
+ cancel_work_sync(&dev_priv->hotplug.hotplug_work);
+ cancel_delayed_work_sync(&dev_priv->hotplug.reenable_work);
+}