[Intel-gfx] [PATCH v3 4/4] drm/i915/debugfs: Print PSR selective update status register values

[José Roberto de Souza]

The value of this registers will be used to test if PSR2 is doing
selective update and if the number of blocks match with the expected.

v2:
- Using new macros
- Changed the string output

v3:
- reading PSR2_SU_STATUS registers together(Dhinakaran)
- printing SU blocks of frames with 0 updates(Dhinakaran)

Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
---
 drivers/gpu/drm/i915/i915_debugfs.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index f8668cb05d64..5817ae0fb5f8 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -2600,6 +2600,29 @@ static int i915_edp_psr_status(struct seq_file *m, void *data)
 		seq_printf(m, "Last exit at: %lld\n", psr->last_exit);
 	}
 
+	if (psr->psr2_enabled) {
+		u32 su_frames_val[3];
+		u8 frame;
+
+		/*
+		 * Reading all 3 registers before hand to minimize crossing a
+		 * frame boundary between register reads
+		 */
+		for (frame = 0; frame < PSR2_SU_STATUS_FRAMES; frame += 3)
+			su_frames_val[frame / 3] = I915_READ(PSR2_SU_STATUS(frame));
+
+		seq_puts(m, "Frame:\tPSR2 SU blocks:\n");
+
+		for (frame = 0; frame < PSR2_SU_STATUS_FRAMES; frame++) {
+			u32 su_blocks;
+
+			su_blocks = su_frames_val[frame / 3] &
+				    PSR2_SU_STATUS_MASK(frame);
+			su_blocks = su_blocks >> PSR2_SU_STATUS_SHIFT(frame);
+			seq_printf(m, "%d\t%d\n", frame, su_blocks);
+		}
+	}
+
 unlock:
 	mutex_unlock(&psr->lock);
 	intel_runtime_pm_put(dev_priv);
-- 
2.20.1