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UBUNTU: SAUCE: i915_bpo: drm/i915/skl: disable display side power well support for now

Message ID 1452183560-28181-2-git-send-email-tjaalton@ubuntu.com
State New
Headers show

Commit Message

Timo Aaltonen Jan. 7, 2016, 4:19 p.m. UTC 
From: Imre Deak <imre.deak@intel.com>

BugLink: http://bugs.launchpad.net/bugs/1526220

The display power well support on this platform is in a somewhat broken
state atm, so disable it by default.

This in effect will get rid of incorrect assert WARNs about the CSR/DMC
firmware not being loaded during power well toggling. It also removes a
problem during driver loading where a register is accessed while its
backing power well is down, resulting in another WARN. Until we come up
with the root cause of the second problem and the proper fix for both
issues, keep all display side power wells on.

Also clarify a bit the option description.

Reported-by: Dave Airlie <airlied@redhat.com>
Reference: http://mid.gmane.org/CAPM=9tyjBQjSBTKa49cRr6SYkpNW7Pq-fUFznZZ8Y1snvvk7mA@mail.gmail.com
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446757451-2777-1-git-send-email-imre.deak@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
(cherry picked from commit 1b0e3a049efe471c399674fd954500ce97438d30)
Signed-off-by: Timo Aaltonen <timo.aaltonen@canonical.com>
---
 ubuntu/i915/i915_params.c      |  5 +++--
 ubuntu/i915/intel_runtime_pm.c | 18 ++++++++++++++++++
 2 files changed, 21 insertions(+), 2 deletions(-)
diff mbox

Patch

diff --git a/ubuntu/i915/i915_params.c b/ubuntu/i915/i915_params.c
index 8ac5a1b..d73cea2 100644
--- a/ubuntu/i915/i915_params.c
+++ b/ubuntu/i915/i915_params.c
@@ -39,7 +39,7 @@  struct i915_params i915 __read_mostly = {
 	.enable_ppgtt = -1,
 	.enable_psr = 0,
 	.preliminary_hw_support = IS_ENABLED(CONFIG_DRM_I915_PRELIMINARY_HW_SUPPORT),
-	.disable_power_well = 1,
+	.disable_power_well = -1,
 	.enable_ips = 1,
 	.fastboot = 0,
 	.prefault_disable = 0,
@@ -132,7 +132,8 @@  MODULE_PARM_DESC(preliminary_hw_support,
 
 module_param_named(disable_power_well, i915.disable_power_well, int, 0600);
 MODULE_PARM_DESC(disable_power_well,
-	"Disable the power well when possible (default: true)");
+	"Disable display power wells when possible "
+	"(-1=auto [default], 0=power wells always on, 1=power wells disabled when possible)");
 
 module_param_named(enable_ips, i915.enable_ips, int, 0600);
 MODULE_PARM_DESC(enable_ips, "Enable IPS (default: true)");
diff --git a/ubuntu/i915/intel_runtime_pm.c b/ubuntu/i915/intel_runtime_pm.c
index d78b8a9..6ba5c2e0 100644
--- a/ubuntu/i915/intel_runtime_pm.c
+++ b/ubuntu/i915/intel_runtime_pm.c
@@ -1531,6 +1531,21 @@  static struct i915_power_well bxt_power_wells[] = {
 	}
 };
 
+static int
+sanitize_disable_power_well_option(const struct drm_i915_private *dev_priv,
+				   int disable_power_well)
+{
+	if (disable_power_well >= 0)
+		return !!disable_power_well;
+
+	if (IS_SKYLAKE(dev_priv)) {
+		DRM_DEBUG_KMS("Disabling display power well support\n");
+		return 0;
+	}
+
+	return 1;
+}
+
 #define set_power_wells(power_domains, __power_wells) ({		\
 	(power_domains)->power_wells = (__power_wells);			\
 	(power_domains)->power_well_count = ARRAY_SIZE(__power_wells);	\
@@ -1547,6 +1562,9 @@  int intel_power_domains_init(struct drm_i915_private *dev_priv)
 {
 	struct i915_power_domains *power_domains = &dev_priv->power_domains;
 
+	i915.disable_power_well = sanitize_disable_power_well_option(dev_priv,
+						     i915.disable_power_well);
+
 	mutex_init(&power_domains->lock);
 
 	/*