aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/brcm2708/patches-4.19/950-0585-drm-v3d-Make-sure-the-GPU-is-on-when-measuring-clock.patch
blob: 7daa2043f73f1042cf4a8245f058fffe14768bfe (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
From 51a1e9604fdd215581d7974a185809b1ac93adac Mon Sep 17 00:00:00 2001
From: Eric Anholt <eric@anholt.net>
Date: Mon, 14 Jan 2019 17:26:04 -0800
Subject: [PATCH 585/703] drm/v3d: Make sure the GPU is on when measuring
 clocks.

You'll get garbage measurements if the registers always read back
0xdeadbeef

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 drivers/gpu/drm/v3d/v3d_debugfs.c | 8 ++++++++
 1 file changed, 8 insertions(+)

--- a/drivers/gpu/drm/v3d/v3d_debugfs.c
+++ b/drivers/gpu/drm/v3d/v3d_debugfs.c
@@ -187,6 +187,11 @@ static int v3d_measure_clock(struct seq_
 	uint32_t cycles;
 	int core = 0;
 	int measure_ms = 1000;
+	int ret;
+
+	ret = pm_runtime_get_sync(v3d->dev);
+	if (ret < 0)
+		return ret;
 
 	if (v3d->ver >= 40) {
 		V3D_CORE_WRITE(core, V3D_V4_PCTR_0_SRC_0_3,
@@ -210,6 +215,9 @@ static int v3d_measure_clock(struct seq_
 		   cycles / (measure_ms * 1000),
 		   (cycles / (measure_ms * 100)) % 10);
 
+	pm_runtime_mark_last_busy(v3d->dev);
+	pm_runtime_put_autosuspend(v3d->dev);
+
 	return 0;
 }