target/linux/brcm2708/patches-4.19/950-0579-drm-v3d-Make-sure-the-GPU-is-on-when-measuring-clock.patch

   1 From 452de2d412157502f7365517eb21d2aaa25d5133 Mon Sep 17 00:00:00 2001
   2 From: Eric Anholt <eric@anholt.net>
   3 Date: Mon, 14 Jan 2019 17:26:04 -0800
   4 Subject: [PATCH 579/773] drm/v3d: Make sure the GPU is on when measuring
   5  clocks.
   6
   7 You'll get garbage measurements if the registers always read back
   8 0xdeadbeef
   9
  10 Signed-off-by: Eric Anholt <eric@anholt.net>
  11 ---
  12  drivers/gpu/drm/v3d/v3d_debugfs.c | 8 ++++++++
  13  1 file changed, 8 insertions(+)
  14
  15 --- a/drivers/gpu/drm/v3d/v3d_debugfs.c
  16 +++ b/drivers/gpu/drm/v3d/v3d_debugfs.c
  17 @@ -187,6 +187,11 @@ static int v3d_measure_clock(struct seq_
  18         uint32_t cycles;
  19         int core = 0;
  20         int measure_ms = 1000;
  21 +       int ret;
  22 +
  23 +       ret = pm_runtime_get_sync(v3d->dev);
  24 +       if (ret < 0)
  25 +               return ret;
  26
  27         if (v3d->ver >= 40) {
  28                 V3D_CORE_WRITE(core, V3D_V4_PCTR_0_SRC_0_3,
  29 @@ -210,6 +215,9 @@ static int v3d_measure_clock(struct seq_
  30                    cycles / (measure_ms * 1000),
  31                    (cycles / (measure_ms * 100)) % 10);
  32
  33 +       pm_runtime_mark_last_busy(v3d->dev);
  34 +       pm_runtime_put_autosuspend(v3d->dev);
  35 +
  36         return 0;
  37  }
  38