[PATCH 07/16] drm/i915: Add bigjoiner and uncompressed joiner hw readout sanity checks

[Ankit Nautiyal]

From: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>

Add sanity checks for primary and secondary bigjoiner/uncompressed
bitmasks, should make it easier to spot possible issues.

v2:
-Streamline the expected masks and add few more drm_WARNs. (Ville)
-Use %#x format specifier for printing joiner masks. (Ville)
-Use struct intel_display instead of struct drm_i915_private. (Ankit)

v3:
-Rename helper to get expected uncompressed joiner pipes. (Ville)

Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>
Reviewed-by: Suraj Kandpal <suraj.kandpal at intel.com> (v1)
Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_display.c | 51 +++++++++++++++++++-
 1 file changed, 49 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index d2c992259476..ee57e1e544af 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -3643,26 +3643,73 @@ static void enabled_bigjoiner_pipes(struct intel_display *display,
 	}
 }
 
+static u8 expected_secondary_pipes(u8 primary_pipes, int num_pipes)
+{
+	u8 secondary_pipes = 0;
+
+	for (int i = 1; i < num_pipes; i++)
+		secondary_pipes |= primary_pipes << i;
+
+	return secondary_pipes;
+}
+
+static u8 expected_uncompressed_joiner_secondary_pipes(u8 uncompjoiner_primary_pipes)
+{
+	return expected_secondary_pipes(uncompjoiner_primary_pipes, 2);
+}
+
+static u8 expected_bigjoiner_secondary_pipes(u8 bigjoiner_primary_pipes)
+{
+	return expected_secondary_pipes(bigjoiner_primary_pipes, 2);
+}
+
 static void enabled_joiner_pipes(struct drm_i915_private *dev_priv,
 				 u8 *primary_pipes, u8 *secondary_pipes)
 {
 	struct intel_display *display = to_intel_display(&dev_priv->drm);
 	u8 primary_uncompressed_joiner_pipes, primary_bigjoiner_pipes;
 	u8 secondary_uncompressed_joiner_pipes, secondary_bigjoiner_pipes;
+	u8 uncompressed_joiner_pipes, bigjoiner_pipes;
 
 	enabled_uncompressed_joiner_pipes(display, &primary_uncompressed_joiner_pipes,
 					  &secondary_uncompressed_joiner_pipes);
 
+	drm_WARN_ON(display->drm,
+		    (primary_uncompressed_joiner_pipes & secondary_uncompressed_joiner_pipes) != 0);
+
 	enabled_bigjoiner_pipes(display, &primary_bigjoiner_pipes,
 				&secondary_bigjoiner_pipes);
 
+	drm_WARN_ON(display->drm,
+		    (primary_bigjoiner_pipes & secondary_bigjoiner_pipes) != 0);
+
+	uncompressed_joiner_pipes = primary_uncompressed_joiner_pipes |
+				    secondary_uncompressed_joiner_pipes;
+	bigjoiner_pipes = primary_bigjoiner_pipes | secondary_bigjoiner_pipes;
+
+	drm_WARN(display->drm, (uncompressed_joiner_pipes & bigjoiner_pipes) != 0,
+		 "Uncomressed joiner pipes(%#x) and bigjoiner pipes(%#x) can't intersect\n",
+		 uncompressed_joiner_pipes, bigjoiner_pipes);
+
+	drm_WARN(display->drm, secondary_bigjoiner_pipes !=
+		 expected_bigjoiner_secondary_pipes(primary_bigjoiner_pipes),
+		 "Wrong secondary bigjoiner pipes(expected %#x, current %#x)\n",
+		 expected_bigjoiner_secondary_pipes(primary_bigjoiner_pipes),
+		 secondary_bigjoiner_pipes);
+
+	drm_WARN(display->drm, secondary_uncompressed_joiner_pipes !=
+		 expected_uncompressed_joiner_secondary_pipes(primary_uncompressed_joiner_pipes),
+		 "Wrong secondary uncompressed joiner pipes(expected %#x, current %#x)\n",
+		 expected_uncompressed_joiner_secondary_pipes(primary_uncompressed_joiner_pipes),
+		 secondary_uncompressed_joiner_pipes);
+
 	*primary_pipes = primary_uncompressed_joiner_pipes | primary_bigjoiner_pipes;
 
 	*secondary_pipes = secondary_uncompressed_joiner_pipes | secondary_bigjoiner_pipes;
 
 	/* Joiner pipes should always be consecutive primary and secondary */
-	drm_WARN(&dev_priv->drm, *secondary_pipes != *primary_pipes << 1,
-		 "Joiner misconfigured (primary pipes 0x%x, secondary pipes 0x%x)\n",
+	drm_WARN(display->drm, *secondary_pipes != *primary_pipes << 1,
+		 "Joiner misconfigured (primary pipes %#x, secondary pipes %#x)\n",
 		 *primary_pipes, *secondary_pipes);
 }
 
-- 
2.45.2