drm/i915/fbc: Introduce device info fbc_mask

Declare which FBC instances are present via a fbc_mask
in device info. For the moment there is just the one.

TODO: Need to figure out how to expose multiple FBC
instances in debugs. Just different file names, or move
the files under some subdirectory (per-crtc maybe), or
something else? This will need igt changes as well.

v2: Put the mask into device_info.display (Jani)
    Put the magic pipe->fbc thing into skl_fbc_id_for_pipe() (Jani)

Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211213134450.3082-4-ville.syrjala@linux.intel.com

2 files changed, 33 insertions, 22 deletions

diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
index a73256f22a1e..796453e1c101 100644
--- a/drivers/gpu/drm/i915/display/intel_fbc.c
+++ b/drivers/gpu/drm/i915/display/intel_fbc.c
@@ -49,11 +49,12 @@
 #include "intel_fbc.h"
 #include "intel_frontbuffer.h"
 
-#define for_each_fbc_id(__fbc_id) \
-	for ((__fbc_id) = INTEL_FBC_A; (__fbc_id) < I915_MAX_FBCS; (__fbc_id)++)
+#define for_each_fbc_id(__dev_priv, __fbc_id) \
+	for ((__fbc_id) = INTEL_FBC_A; (__fbc_id) < I915_MAX_FBCS; (__fbc_id)++) \
+		for_each_if(INTEL_INFO(__dev_priv)->display.fbc_mask & BIT(__fbc_id))
 
 #define for_each_intel_fbc(__dev_priv, __fbc, __fbc_id) \
-	for_each_fbc_id(__fbc_id) \
+	for_each_fbc_id((__dev_priv), (__fbc_id)) \
 		for_each_if((__fbc) = (__dev_priv)->fbc[(__fbc_id)])
 
 struct intel_fbc_funcs {
@@ -1693,32 +1694,35 @@ static struct intel_fbc *intel_fbc_create(struct drm_i915_private *i915,
  */
 void intel_fbc_init(struct drm_i915_private *i915)
 {
-	struct intel_fbc *fbc;
+	enum intel_fbc_id fbc_id;
 
 	if (!drm_mm_initialized(&i915->mm.stolen))
-		mkwrite_device_info(i915)->display.has_fbc = false;
+		mkwrite_device_info(i915)->display.fbc_mask = 0;
 
 	if (need_fbc_vtd_wa(i915))
-		mkwrite_device_info(i915)->display.has_fbc = false;
+		mkwrite_device_info(i915)->display.fbc_mask = 0;
 
 	i915->params.enable_fbc = intel_sanitize_fbc_option(i915);
 	drm_dbg_kms(&i915->drm, "Sanitized enable_fbc value: %d\n",
 		    i915->params.enable_fbc);
 
-	if (!HAS_FBC(i915))
-		return;
+	for_each_fbc_id(i915, fbc_id) {
+		struct intel_fbc *fbc;
 
-	fbc = intel_fbc_create(i915, INTEL_FBC_A);
-	if (!fbc)
-		return;
+		fbc = intel_fbc_create(i915, fbc_id);
+		if (!fbc)
+			continue;
 
-	/* We still don't have any sort of hardware state readout for FBC, so
-	 * deactivate it in case the BIOS activated it to make sure software
-	 * matches the hardware state. */
-	if (intel_fbc_hw_is_active(fbc))
-		intel_fbc_hw_deactivate(fbc);
+		/*
+		 * We still don't have any sort of hardware state readout
+		 * for FBC, so deactivate it in case the BIOS activated it
+		 * to make sure software matches the hardware state.
+		 */
+		if (intel_fbc_hw_is_active(fbc))
+			intel_fbc_hw_deactivate(fbc);
 
-	i915->fbc[fbc->id] = fbc;
+		i915->fbc[fbc->id] = fbc;
+	}
 }
 
 static int intel_fbc_debugfs_status_show(struct seq_file *m, void *unused)
diff --git a/drivers/gpu/drm/i915/display/skl_universal_plane.c b/drivers/gpu/drm/i915/display/skl_universal_plane.c
index 3db57cd7474b..158d89b8d490 100644
--- a/drivers/gpu/drm/i915/display/skl_universal_plane.c
+++ b/drivers/gpu/drm/i915/display/skl_universal_plane.c
@@ -1816,20 +1816,27 @@ static int skl_plane_check(struct intel_crtc_state *crtc_state,
 	return 0;
 }
 
+static enum intel_fbc_id skl_fbc_id_for_pipe(enum pipe pipe)
+{
+	return pipe - PIPE_A + INTEL_FBC_A;
+}
+
 static bool skl_plane_has_fbc(struct drm_i915_private *dev_priv,
-			      enum pipe pipe, enum plane_id plane_id)
+			      enum intel_fbc_id fbc_id, enum plane_id plane_id)
 {
-	if (!HAS_FBC(dev_priv))
+	if ((INTEL_INFO(dev_priv)->display.fbc_mask & BIT(fbc_id)) == 0)
 		return false;
 
-	return pipe == PIPE_A && plane_id == PLANE_PRIMARY;
+	return plane_id == PLANE_PRIMARY;
 }
 
 static struct intel_fbc *skl_plane_fbc(struct drm_i915_private *dev_priv,
 				       enum pipe pipe, enum plane_id plane_id)
 {
-	if (skl_plane_has_fbc(dev_priv, pipe, plane_id))
-		return dev_priv->fbc[INTEL_FBC_A];
+	enum intel_fbc_id fbc_id = skl_fbc_id_for_pipe(pipe);
+
+	if (skl_plane_has_fbc(dev_priv, fbc_id, plane_id))
+		return dev_priv->fbc[fbc_id];
 	else
 		return NULL;
 }