[PATCH i-g-t v4 3/4] lib/igt_kms: loosen duplicate check in igt_display_refresh

[Jessica Zhang <quic_jesszhan@quicinc.com>]

From: Esha Bharadwaj <quic_ebharadw@quicinc.com>

Change the duplicate check in igt_display_refresh() so it allows for
pipes to be shared by encoders that are valid clones of each other.

Signed-off-by: Esha Bharadwaj <quic_ebharadw@quicinc.com>
Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
---
 lib/igt_kms.c | 42 +++++++++++++++++++++++++++++++++---------
 lib/igt_kms.h |  1 +
 2 files changed, 34 insertions(+), 9 deletions(-)

diff --git a/lib/igt_kms.c b/lib/igt_kms.c
index f5fab7f73..a17efc364 100644
--- a/lib/igt_kms.c
+++ b/lib/igt_kms.c
@@ -3286,22 +3286,46 @@ int kmstest_get_encoder_idx(drmModeRes *resources, drmModeEncoder *encoder)
 	igt_assert(0);
 }
 
-static void igt_display_refresh(igt_display_t *display)
+bool igt_output_clone_valid(int drm_fd, igt_output_t *target, igt_output_t *clone)
 {
-	igt_output_t *output;
-	int i;
+	drmModeEncoder *target_enc;
+	drmModeEncoder *clone_enc;
+	drmModeRes *resources = drmModeGetResources(drm_fd);
+	uint32_t clone_mask;
+
+	if (!target || !clone)
+		return false;
+
+	target_enc = target->config.encoder;
+	clone_enc = clone->config.encoder;
+
+	if (!target_enc || !clone_enc)
+		return false;
+
+	clone_mask = 1 << kmstest_get_encoder_idx(resources, clone_enc);
 
-	unsigned long pipes_in_use = 0;
+	return ((target_enc->possible_clones & clone_mask) != clone_mask);
+}
+
+static void igt_display_refresh(igt_display_t *display)
+{
+	igt_output_t *output, *clone_output;
+	int i, j;
 
-       /* Check that two outputs aren't trying to use the same pipe */
 	for (i = 0; i < display->n_outputs; i++) {
 		output = &display->outputs[i];
 
-		if (output->pending_pipe != PIPE_NONE) {
-			if (pipes_in_use & (1 << output->pending_pipe))
-				goto report_dup;
+		for (j = i + 1; j < display->n_outputs; j++) {
+			clone_output = &display->outputs[j];
 
-			pipes_in_use |= 1 << output->pending_pipe;
+			/*
+			 * Check that any encoders with duplicated pipes are
+			 * possible clones of each other. If they aren't, report
+			 * the pipe as duplicated
+			 */
+			if (!igt_output_clone_valid(display->drm_fd,
+						output, clone_output))
+				goto report_dup;
 		}
 
 		if (output->force_reprobe)
diff --git a/lib/igt_kms.h b/lib/igt_kms.h
index 72fe3b3b1..2d272f1fa 100644
--- a/lib/igt_kms.h
+++ b/lib/igt_kms.h
@@ -525,6 +525,7 @@ igt_plane_t *igt_output_get_plane_type_index(igt_output_t *output,
 					     int plane_type, int index);
 igt_output_t *igt_output_from_connector(igt_display_t *display,
     drmModeConnector *connector);
+bool igt_output_clone_valid(int drm_fd, igt_output_t *target, igt_output_t *clone);
 void igt_output_refresh(igt_output_t *output);
 drmModeModeInfo *igt_std_1024_mode_get(int vrefresh);
 void igt_output_set_writeback_fb(igt_output_t *output, struct igt_fb *fb);

-- 
2.34.1