1 From 18f93916e42ea25fc77cab20d1e038620e33d741 Mon Sep 17 00:00:00 2001
2 From: Eric Anholt <eric@anholt.net>
3 Date: Fri, 28 Sep 2018 16:21:24 -0700
4 Subject: [PATCH] drm/v3d: Add a little debugfs entry for measuring the
7 This adds just enough performance counter support to measure the
8 clock. We don't have linux kernel drivers for the clock driving the
9 HW, and this was useful for determining that the V3D HW is running on
10 a slow clock, not that the driver was slow.
12 Signed-off-by: Eric Anholt <eric@anholt.net>
13 Link: https://patchwork.freedesktop.org/patch/msgid/20180928232126.4332-2-eric@anholt.net
14 Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
15 (cherry picked from commit 6915c9a525e575732429c22b28eb11871a29374b)
17 drivers/gpu/drm/v3d/v3d_debugfs.c | 35 +++++++++++++++++++++++++++++++
18 drivers/gpu/drm/v3d/v3d_regs.h | 30 ++++++++++++++++++++++++++
19 2 files changed, 65 insertions(+)
21 --- a/drivers/gpu/drm/v3d/v3d_debugfs.c
22 +++ b/drivers/gpu/drm/v3d/v3d_debugfs.c
23 @@ -179,9 +179,44 @@ static int v3d_debugfs_bo_stats(struct s
27 +static int v3d_measure_clock(struct seq_file *m, void *unused)
29 + struct drm_info_node *node = (struct drm_info_node *)m->private;
30 + struct drm_device *dev = node->minor->dev;
31 + struct v3d_dev *v3d = to_v3d_dev(dev);
34 + int measure_ms = 1000;
36 + if (v3d->ver >= 40) {
37 + V3D_CORE_WRITE(core, V3D_V4_PCTR_0_SRC_0_3,
38 + V3D_SET_FIELD(V3D_PCTR_CYCLE_COUNT,
40 + V3D_CORE_WRITE(core, V3D_V4_PCTR_0_CLR, 1);
41 + V3D_CORE_WRITE(core, V3D_V4_PCTR_0_EN, 1);
43 + V3D_CORE_WRITE(core, V3D_V3_PCTR_0_PCTRS0,
44 + V3D_PCTR_CYCLE_COUNT);
45 + V3D_CORE_WRITE(core, V3D_V3_PCTR_0_CLR, 1);
46 + V3D_CORE_WRITE(core, V3D_V3_PCTR_0_EN,
47 + V3D_V3_PCTR_0_EN_ENABLE |
51 + cycles = V3D_CORE_READ(core, V3D_PCTR_0_PCTR0);
53 + seq_printf(m, "cycles: %d (%d.%d Mhz)\n",
55 + cycles / (measure_ms * 1000),
56 + (cycles / (measure_ms * 100)) % 10);
61 static const struct drm_info_list v3d_debugfs_list[] = {
62 {"v3d_ident", v3d_v3d_debugfs_ident, 0},
63 {"v3d_regs", v3d_v3d_debugfs_regs, 0},
64 + {"measure_clock", v3d_measure_clock, 0},
65 {"bo_stats", v3d_debugfs_bo_stats, 0},
68 --- a/drivers/gpu/drm/v3d/v3d_regs.h
69 +++ b/drivers/gpu/drm/v3d/v3d_regs.h
71 # define V3D_PTB_BXCF_RWORDERDISA BIT(1)
72 # define V3D_PTB_BXCF_CLIPDISA BIT(0)
74 +#define V3D_V3_PCTR_0_EN 0x00674
75 +#define V3D_V3_PCTR_0_EN_ENABLE BIT(31)
76 +#define V3D_V4_PCTR_0_EN 0x00650
77 +/* When a bit is set, resets the counter to 0. */
78 +#define V3D_V3_PCTR_0_CLR 0x00670
79 +#define V3D_V4_PCTR_0_CLR 0x00654
80 +#define V3D_PCTR_0_OVERFLOW 0x00658
82 +#define V3D_V3_PCTR_0_PCTRS0 0x00684
83 +#define V3D_V3_PCTR_0_PCTRS15 0x00660
84 +#define V3D_V3_PCTR_0_PCTRSX(x) (V3D_V3_PCTR_0_PCTRS0 + \
86 +/* Each src reg muxes four counters each. */
87 +#define V3D_V4_PCTR_0_SRC_0_3 0x00660
88 +#define V3D_V4_PCTR_0_SRC_28_31 0x0067c
89 +# define V3D_PCTR_S0_MASK V3D_MASK(6, 0)
90 +# define V3D_PCTR_S0_SHIFT 0
91 +# define V3D_PCTR_S1_MASK V3D_MASK(14, 8)
92 +# define V3D_PCTR_S1_SHIFT 8
93 +# define V3D_PCTR_S2_MASK V3D_MASK(22, 16)
94 +# define V3D_PCTR_S2_SHIFT 16
95 +# define V3D_PCTR_S3_MASK V3D_MASK(30, 24)
96 +# define V3D_PCTR_S3_SHIFT 24
97 +# define V3D_PCTR_CYCLE_COUNT 32
99 +/* Output values of the counters. */
100 +#define V3D_PCTR_0_PCTR0 0x00680
101 +#define V3D_PCTR_0_PCTR31 0x006fc
102 +#define V3D_PCTR_0_PCTRX(x) (V3D_PCTR_0_PCTR0 + \
104 #define V3D_GMP_STATUS 0x00800
105 # define V3D_GMP_STATUS_GMPRST BIT(31)
106 # define V3D_GMP_STATUS_WR_COUNT_MASK V3D_MASK(30, 24)