[PATCH 3/5] drm/i915: Add IPS debugfs disabling

[jeff.mcgee@intel.com]

From: Jeff McGee <jeff.mcgee@intel.com>

i915_ips_disable:
'0' - IPS enabled normally per device and settings.
'1' - IPS explicitly disabled.

Signed-off-by: Jeff McGee <jeff.mcgee@intel.com>
---
 drivers/gpu/drm/i915/i915_debugfs.c  | 47 ++++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/i915/i915_drv.h      |  2 ++
 drivers/gpu/drm/i915/intel_display.c |  4 +++
 3 files changed, 53 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index a51c357..949c6a4 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -1413,6 +1413,52 @@ static int i915_ips_status(struct seq_file *m, void *unused)
 	return 0;
 }
 
+static int i915_ips_disable_get(void *data, u64 *val)
+{
+	struct drm_device *dev = data;
+	drm_i915_private_t *dev_priv = dev->dev_private;
+
+	if (!HAS_IPS(dev))
+		return -ENODEV;
+
+	*val = dev_priv->ips_disable;
+
+	return 0;
+}
+
+static int i915_ips_disable_set(void *data, u64 val)
+{
+	struct drm_device *dev = data;
+	drm_i915_private_t *dev_priv = dev->dev_private;
+	struct drm_crtc *crtc;
+
+	if (!HAS_IPS(dev))
+		return -ENODEV;
+
+	if (dev_priv->ips_disable == (bool)val)
+		return 0;
+
+	drm_modeset_lock_all(dev);
+
+	DRM_DEBUG_DRIVER("Setting IPS disable %s\n",
+			 val ? "true" : "false");
+
+	dev_priv->ips_disable = (bool)val;
+
+	/* Reset enabled crtc to force IPS state update */
+	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
+		if (crtc->enabled)
+			intel_crtc_restore_mode(crtc);
+
+	drm_modeset_unlock_all(dev);
+
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(i915_ips_disable_fops,
+			i915_ips_disable_get, i915_ips_disable_set,
+			"%llu\n");
+
 static int i915_sr_status(struct seq_file *m, void *unused)
 {
 	struct drm_info_node *node = (struct drm_info_node *) m->private;
@@ -3656,6 +3702,7 @@ static const struct i915_debugfs_files {
 	{"i915_cur_freq", &i915_cur_freq_fops},
 	{"i915_rps_manual", &i915_rps_manual_fops},
 	{"i915_rc6_disable", &i915_rc6_disable_fops},
+	{"i915_ips_disable", &i915_ips_disable_fops},
 	{"i915_cache_sharing", &i915_cache_sharing_fops},
 	{"i915_ring_stop", &i915_ring_stop_fops},
 	{"i915_ring_missed_irq", &i915_ring_missed_irq_fops},
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 9893451..93e1547 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1532,6 +1532,8 @@ typedef struct drm_i915_private {
 	 * mchdev_lock in intel_pm.c */
 	struct intel_ilk_power_mgmt ips;
 
+	bool ips_disable;
+
 	struct i915_power_domains power_domains;
 
 	struct i915_psr psr;
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 4d4a0d9..5af41ce 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4580,7 +4580,11 @@ retry:
 static void hsw_compute_ips_config(struct intel_crtc *crtc,
 				   struct intel_crtc_config *pipe_config)
 {
+	struct drm_device *dev = crtc->base.dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
 	pipe_config->ips_enabled = i915.enable_ips &&
+				   !dev_priv->ips_disable &&
 				   hsw_crtc_supports_ips(crtc) &&
 				   pipe_config->pipe_bpp <= 24;
 }
-- 
1.8.5.2