[Intel-gfx] [PATCH v4 2/5] drm/i915/bxt: VBT changes for hpd as wakeup feature

[Animesh Manna]

To support hpd during sleep a new feature flag is
added in vbt and also in dev_priv for enabling/disabling
inside driver. By default this feature will be
disabled and based on oem request this feature can
be enabled by changing vbt feature flag.

v1: Initial version as RFC.

v2: Based on review comments from Jani,
- Used bool instead of enum for hpd feature flag.
- Updating feature flag at the first place based on vbt
entry.

v3: Based on review comment from Jani,
    - removed the if condition check, directly update driver flag
    with vbt feature flag.

Signed-off-by: Animesh Manna <animesh.manna at intel.com>
Signed-off-by: A.Sunil Kamath <sunil.kamath at intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h       | 3 +++
 drivers/gpu/drm/i915/intel_bios.c     | 4 ++++
 drivers/gpu/drm/i915/intel_vbt_defs.h | 3 ++-
 3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 81dd9e9..96b989b 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1672,6 +1672,9 @@ struct intel_vbt_data {
 		const u8 *sequence[MIPI_SEQ_MAX];
 	} dsi;
 
+	/* HPD as wakesoure for DC9 BXT */
+	bool hpd_wakeup_enabled;
+
 	int crt_ddc_pin;
 
 	int child_dev_num;
diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
index 639d45c..4f724ce 100644
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -561,6 +561,10 @@ static int intel_bios_ssc_frequency(struct drm_i915_private *dev_priv,
 	if (driver->lvds_config == BDB_DRIVER_FEATURE_EDP)
 		dev_priv->vbt.edp.support = 1;
 
+	dev_priv->vbt.hpd_wakeup_enabled = driver->hpd_wakeup_source;
+	DRM_DEBUG_KMS("HPD as wakeup source:%s\n",
+		      yesno(driver->hpd_wakeup_source));
+
 	DRM_DEBUG_KMS("DRRS State Enabled:%d\n", driver->drrs_enabled);
 	/*
 	 * If DRRS is not supported, drrs_type has to be set to 0.
diff --git a/drivers/gpu/drm/i915/intel_vbt_defs.h b/drivers/gpu/drm/i915/intel_vbt_defs.h
index a92e776..608e7dd 100644
--- a/drivers/gpu/drm/i915/intel_vbt_defs.h
+++ b/drivers/gpu/drm/i915/intel_vbt_defs.h
@@ -563,7 +563,8 @@ struct bdb_driver_features {
 	u16 tbt_enabled:1;
 	u16 psr_enabled:1;
 	u16 ips_enabled:1;
-	u16 reserved3:4;
+	u16 reserved3:3;
+	u16 hpd_wakeup_source:1;
 	u16 pc_feature_valid:1;
 } __packed;
 
-- 
1.9.1