[Intel-gfx] [PATCH] drm/i915: Enable fastboot by default on Skylake and newer

[Maarten Lankhorst]

From: Hans de Goede <hdegoede at redhat.com>

We really want to have fastboot enabled by default to avoid an ugly
modeset during boot.

Rather then enabling it everywhere, lets start with enabling it on
Skylake and newer.

Signed-off-by: Hans de Goede <hdegoede at redhat.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
---
 drivers/gpu/drm/i915/i915_params.c   |  6 ++++--
 drivers/gpu/drm/i915/i915_params.h   |  2 +-
 drivers/gpu/drm/i915/intel_display.c | 11 ++++++++++-
 3 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c
index 9f0539bdaa39..b5be0abbba35 100644
--- a/drivers/gpu/drm/i915/i915_params.c
+++ b/drivers/gpu/drm/i915/i915_params.c
@@ -97,8 +97,10 @@ i915_param_named_unsafe(disable_power_well, int, 0400,
 
 i915_param_named_unsafe(enable_ips, int, 0600, "Enable IPS (default: true)");
 
-i915_param_named(fastboot, bool, 0600,
-	"Try to skip unnecessary mode sets at boot time (default: false)");
+i915_param_named(fastboot, int, 0600,
+	"Try to skip unnecessary mode sets at boot time "
+	"(0=disabled, 1=enabled) "
+	"Default: -1 (use per-chip default)");
 
 i915_param_named_unsafe(prefault_disable, bool, 0600,
 	"Disable page prefaulting for pread/pwrite/reloc (default:false). "
diff --git a/drivers/gpu/drm/i915/i915_params.h b/drivers/gpu/drm/i915/i915_params.h
index 6efcf330bdab..3f14e9881a0d 100644
--- a/drivers/gpu/drm/i915/i915_params.h
+++ b/drivers/gpu/drm/i915/i915_params.h
@@ -63,10 +63,10 @@ struct drm_printer;
 	param(int, edp_vswing, 0) \
 	param(int, reset, 2) \
 	param(unsigned int, inject_load_failure, 0) \
+	param(int, fastboot, -1) \
 	/* leave bools at the end to not create holes */ \
 	param(bool, alpha_support, IS_ENABLED(CONFIG_DRM_I915_ALPHA_SUPPORT)) \
 	param(bool, enable_hangcheck, true) \
-	param(bool, fastboot, false) \
 	param(bool, prefault_disable, false) \
 	param(bool, load_detect_test, false) \
 	param(bool, force_reset_modeset_test, false) \
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 36c1126cbc85..097e46819d3a 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -11690,6 +11690,15 @@ pipe_config_err(bool adjust, const char *name, const char *format, ...)
 	va_end(args);
 }
 
+static bool fastboot_enabled(struct drm_i915_private *dev_priv)
+{
+	if (i915_modparams.fastboot != -1)
+		return i915_modparams.fastboot;
+
+	/* Enable fastboot by default on Skylake and newer */
+	return INTEL_GEN(dev_priv) >= 9;
+}
+
 static bool
 intel_pipe_config_compare(struct drm_i915_private *dev_priv,
 			  struct intel_crtc_state *current_config,
@@ -11701,7 +11710,7 @@ intel_pipe_config_compare(struct drm_i915_private *dev_priv,
 		(current_config->base.mode.private_flags & I915_MODE_FLAG_INHERITED) &&
 		!(pipe_config->base.mode.private_flags & I915_MODE_FLAG_INHERITED);
 
-	if (fixup_inherited && !i915_modparams.fastboot) {
+	if (fixup_inherited && !fastboot_enabled(dev_priv)) {
 		DRM_DEBUG_KMS("initial modeset and fastboot not set\n");
 		ret = false;
 	}
-- 
2.20.1