[igt-dev] [PATCH i-g-t] tests/kms_dither: New IGT to validate crtc Dithering

Modem, Bhanuprakash bhanuprakash.modem at intel.com
Fri Jul 24 12:56:45 UTC 2020


> -----Original Message-----
> From: Shankar, Uma <uma.shankar at intel.com>
> Sent: Friday, July 24, 2020 4:41 PM
> To: Modem, Bhanuprakash <bhanuprakash.modem at intel.com>; igt-
> dev at lists.freedesktop.org
> Cc: Sharma, Swati2 <swati2.sharma at intel.com>; B S, Karthik
> <karthik.b.s at intel.com>; Laxminarayan Bharadiya, Pankaj
> <pankaj.laxminarayan.bharadiya at intel.com>; Latvala, Petri
> <petri.latvala at intel.com>; Hiler, Arkadiusz <arkadiusz.hiler at intel.com>
> Subject: RE: [PATCH i-g-t] tests/kms_dither: New IGT to validate crtc
> Dithering
> 
> 
> 
> > -----Original Message-----
> > From: Modem, Bhanuprakash <bhanuprakash.modem at intel.com>
> > Sent: Friday, July 24, 2020 4:25 AM
> > To: Modem, Bhanuprakash <bhanuprakash.modem at intel.com>; igt-
> > dev at lists.freedesktop.org
> > Cc: Sharma, Swati2 <swati2.sharma at intel.com>; B S, Karthik
> > <karthik.b.s at intel.com>; Shankar, Uma <uma.shankar at intel.com>;
> > Laxminarayan Bharadiya, Pankaj
> <pankaj.laxminarayan.bharadiya at intel.com>;
> > Latvala, Petri <petri.latvala at intel.com>; Hiler, Arkadiusz
> > <arkadiusz.hiler at intel.com>
> > Subject: [PATCH i-g-t] tests/kms_dither: New IGT to validate crtc
> Dithering
> >
> > Many of the display devices have color format support less than the
> color format
> > of the input data (Ex: 8-bit input data and 6-bit display color depth).
> Then the
> > input data will be either truncated or rounded, but this approach
> usually causes
> > loss of detail and also produce large banded areas of a single color
> that
> > significantly differs from the original image.
> >
> > Dithering is a technique used to enhance these colors by creating the
> illusion of
> > smoothness by adjusting the nearby pixel color.
> > For Eg: Converting 8-bit to 6-bit by modifying the pixel information.
> >
> > Dithering should be enabled when a panel color depth is lower than the
> color
> > depth of the framebuffer.
> >
> > Even though feature Dithering is there since legacy, there is no
> specific IGT for
> > this. This patch will create New IGT for Dithering.
> > And below is the truth table for CRTC Dithering.
> >
> > |----------------|---------|-------------|
> > |  Frame buffer  |  Panel  |  Dithering  |
> > |----------------|---------|-------------|
> > |      8 BPC     |  6 BPC  |     Yes     |
> > |----------------|---------|-------------|
> > |      8 BPC     |  8 BPC  |     No      |
> > |----------------|---------|-------------|
> > |      8 BPC     | 10 BPC  |     No      |
> > |----------------|---------|-------------|
> > |     10 BPC     |  6 BPC  |     Yes     |
> > |----------------|---------|-------------|
> > |     10 BPC     |  8 BPC  |     Yes     |
> > |----------------|---------|-------------|
> > |     10 BPC     | 10 BPC  |     No      |
> > |----------------|---------|-------------|
> > |     16 BPC     |  6 BPC  |     Yes     |
> > |----------------|---------|-------------|
> > |     16 BPC     |  8 BPC  |     Yes     |
> > |----------------|---------|-------------|
> > |     16 BPC     | 10 BPC  |     Yes     |
> > |----------------|---------|-------------|
> >
> > v2:
> > * Fix commit message (Karthik)
> > * Add file author (Karthik)
> > * Dynamic subtests for pipe-output combinations (Karthik)
> > * Update deprecated pipe name (Karthik)
> > * Remove redundant fb creation logic (Karthik)
> >
> > v3:
> > * Use for_each_pipe_with_valid_output() to simplify the logic (Bhanu)
> > * Remove magic numbers to create fb (Karthik)
> > * Fix typos & comments (Swati)
> >
> > Cc: Swati Sharma <swati2.sharma at intel.com>
> > Cc: Karthik B S <karthik.b.s at intel.com>
> > Cc: Uma Shankar <uma.shankar at intel.com>
> > Cc: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya at intel.com>
> > Cc: Petri Latvala <petri.latvala at intel.com>
> > Cc: Arkadiusz Hiler <arkadiusz.hiler at intel.com>
> > Signed-off-by: Bhanuprakash Modem <bhanuprakash.modem at intel.com>
> > ---
> >  tests/Makefile.sources |   1 +
> >  tests/kms_dither.c     | 256 +++++++++++++++++++++++++++++++++++++++++
> >  tests/meson.build      |   1 +
> >  3 files changed, 258 insertions(+)
> >  create mode 100644 tests/kms_dither.c
> >
> > diff --git a/tests/Makefile.sources b/tests/Makefile.sources index
> > 0653c3d3..e816037c 100644
> > --- a/tests/Makefile.sources
> > +++ b/tests/Makefile.sources
> > @@ -43,6 +43,7 @@ TESTS_progs = \
> >  	kms_cursor_crc \
> >  	kms_cursor_edge_walk \
> >  	kms_cursor_legacy \
> > +	kms_dither \
> >  	kms_dp_aux_dev \
> >  	kms_dp_dsc \
> >  	kms_dp_tiled_display \
> > diff --git a/tests/kms_dither.c b/tests/kms_dither.c new file mode
> 100644 index
> > 00000000..22d96d34
> > --- /dev/null
> > +++ b/tests/kms_dither.c
> > @@ -0,0 +1,256 @@
> > +/*
> > + * Copyright © 2020 Intel Corporation
> > + *
> > + * Permission is hereby granted, free of charge, to any person
> > +obtaining a
> > + * copy of this software and associated documentation files (the
> > +"Software"),
> > + * to deal in the Software without restriction, including without
> > +limitation
> > + * the rights to use, copy, modify, merge, publish, distribute,
> > +sublicense,
> > + * and/or sell copies of the Software, and to permit persons to whom
> > +the
> > + * Software is furnished to do so, subject to the following conditions:
> > + *
> > + * The above copyright notice and this permission notice (including the
> > +next
> > + * paragraph) shall be included in all copies or substantial portions
> > +of the
> > + * Software.
> > + *
> > + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
> > +EXPRESS OR
> > + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
> > +MERCHANTABILITY,
> > + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT
> > +SHALL
> > + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM,
> > +DAMAGES OR
> > + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
> > +OTHERWISE,
> > + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
> > USE
> > +OR
> > + * OTHER DEALINGS IN THE SOFTWARE.
> > + *
> > + * Authors:
> > + *     Bhanuprakash Modem <bhanuprakash.modem at intel.com>
> > + *
> > + */
> > +
> > +#include "igt.h"
> > +#include <fcntl.h>
> > +#include <termios.h>
> > +#include <unistd.h>
> > +
> > +IGT_TEST_DESCRIPTION("Test Dithering block status");
> > +
> > +/* Connector BPC */
> > +#define IGT_CONNECTOR_BPC_6		6
> > +#define IGT_CONNECTOR_BPC_8		8
> > +#define IGT_CONNECTOR_BPC_10		10
> > +#define IGT_CONNECTOR_BPC_12		12
> > +
> > +/* Framebuffer BPC */
> > +#define IGT_FRAME_BUFFER_BPC_8		8
> > +#define IGT_FRAME_BUFFER_BPC_10		10
> > +#define IGT_FRAME_BUFFER_BPC_16		16
> > +
> > +/* Test flags. */
> > +enum {
> > +	TEST_NONE = 1 << 0,
> > +	TEST_SUSPEND = 1 << 1,
> > +};
> > +
> > +/* Common test data. */
> > +typedef struct data {
> > +	igt_display_t display;
> > +	igt_plane_t *primary;
> > +	igt_output_t *output;
> > +	igt_pipe_t *pipe;
> > +	drmModeModeInfo *mode;
> > +	enum pipe pipe_id;
> > +	int drm_fd;
> > +	igt_fb_t fb;
> > +} data_t;
> > +
> > +/* Prepare test data. */
> > +static void prepare_test(data_t *data, igt_output_t *output, enum pipe
> > +pipe) {
> > +	igt_display_t *display = &data->display;
> > +
> > +	data->pipe_id = pipe;
> > +	data->pipe = &data->display.pipes[data->pipe_id];
> > +	igt_assert(data->pipe);
> > +
> > +	igt_display_reset(display);
> > +
> > +	data->output = output;
> > +	igt_assert(data->output);
> > +
> > +	data->mode = igt_output_get_mode(data->output);
> > +	igt_assert(data->mode);
> > +
> > +	data->primary =
> > +		igt_pipe_get_plane_type(data->pipe,
> > DRM_PLANE_TYPE_PRIMARY);
> > +
> > +	igt_output_set_pipe(data->output, data->pipe_id); }
> > +
> > +/* Returns the current state of dithering from the crtc debugfs. */
> > +static bool get_dither_state(data_t *data) {
> > +	char buf[256];
> > +	char crtc_name[7];
> > +	char *start_loc;
> > +	int fd, res;
> > +	unsigned int status;
> > +
> > +	snprintf(crtc_name, 7, "crtc-%d", data->pipe_id);
> > +	fd = igt_debugfs_open(data->drm_fd, crtc_name, O_RDONLY);
> > +	igt_assert(fd >= 0);
> > +
> > +	res = igt_debugfs_simple_read(fd, "dither", buf, sizeof(buf));
> > +	igt_require(res > 0);
> > +	close(fd);
> > +
> > +	igt_assert(start_loc = strstr(buf, "Dither: "));
> > +	igt_assert_eq(sscanf(start_loc, "Dither: %u", &status), 1);
> > +
> > +	return !!status;
> > +}
> > +
> > +/* Returns the maximum bpc from the connector debugfs. */ static
> > +unsigned int get_output_bpc(data_t *data, igt_output_t *output) {
> > +	char buf[256];
> > +	char *start_loc;
> > +	int fd, res;
> > +	unsigned int max_bpc;
> > +
> > +	fd = igt_debugfs_connector_dir(data->drm_fd, output->name,
> > O_RDONLY);
> > +	igt_assert(fd >= 0);
> > +
> > +	res = igt_debugfs_simple_read(fd, "output_bpc", buf, sizeof(buf));
> > +
> > +	igt_require(res > 0);
> > +
> 
> Drop the extra line.
> 
> > +	close(fd);
> > +
> > +	igt_assert(start_loc = strstr(buf, "Maximum: "));
> > +	igt_assert_eq(sscanf(start_loc, "Maximum: %u", &max_bpc), 1);
> > +
> > +	return max_bpc;
> > +}
> > +
> > +static void test_dithering(data_t *data, enum pipe pipe,
> > +			   igt_output_t *output,
> > +			   int fb_bpc, int fb_format,
> > +			   int output_bpc, uint32_t flags)
> > +{
> > +	igt_display_t *display = &data->display;
> > +	bool enabled;
> > +
> > +	igt_info("Dithering test execution on %s PIPE_%s\n",
> > +			output->name, kmstest_pipe_name(pipe));
> > +	prepare_test(data, output, pipe);
> > +
> > +	igt_assert(igt_create_fb(data->drm_fd, data->mode->hdisplay,
> > +				 data->mode->vdisplay, fb_format,
> > +				 LOCAL_DRM_FORMAT_MOD_NONE, &data->fb));
> > +	igt_plane_set_fb(data->primary, &data->fb);
> > +	igt_plane_set_size(data->primary, data->mode->hdisplay, data->mode-
> > >vdisplay);
> > +	igt_output_set_prop_value(data->output, IGT_CONNECTOR_MAX_BPC,
> > output_bpc);
> > +	igt_display_commit2(display, display->is_atomic ? COMMIT_ATOMIC :
> > +COMMIT_LEGACY);
> > +
> > +	/* Check the status of Dithering block
> 
> Adopt proper multi line comment style.
> 
> > +	 * If fb_bpc is greater than output_bpc, Dithering should be Enabled
> > +	 * else Disabled
> > +	 */
> > +	enabled = get_dither_state(data);
> > +	if (fb_bpc > output_bpc)
> > +		igt_assert_f(enabled, "(fb_%dbpc > output_%dbpc): Dither
> > should be enabled\n",
> > +				fb_bpc, output_bpc);
> > +	else
> > +		igt_assert_f(!enabled, "(fb_%dbpc <= output_%dbpc): Dither
> > should be disabled\n",
> > +				fb_bpc, output_bpc);
> 
> This looks good to validate whether driver returned the right status.
> For features like these, I feel we also should try to see the
> effectiveness of dithering.
[Bhanu] May be we can do this as part of manual E2E testing.
>
> I would propose to have some kind of reference images and
> compare them
> with the output what we get. A chamelium based test can be planned to see
> the really
> effectiveness of dithering. We can have reference golden image and do a
> crc check with
> the output grabbed from sink (through Chamelium).
[Bhanu] I think it is very difficult to maintain the same reference images all over the ci machines.
Yeah, we can do this exercise with our local env.
> 
> > +	igt_plane_set_fb(data->primary, NULL);
> > +	igt_output_set_pipe(output, PIPE_NONE);
> > +	igt_display_commit2(display, display->is_atomic ? COMMIT_ATOMIC :
> > +COMMIT_LEGACY);
> > +
> > +	igt_remove_fb(data->drm_fd, &data->fb);
> > +
> > +	return;
> > +}
> > +
> > +/* Returns true if an output supports max bpc property. */ static bool
> > +has_max_bpc(igt_output_t *output) {
> > +        return igt_output_has_prop(output, IGT_CONNECTOR_MAX_BPC) &&
> > +               igt_output_get_prop(output, IGT_CONNECTOR_MAX_BPC); }
> > +
> > +static void
> > +run_dither_test(data_t *data, int fb_bpc, int fb_format, int
> output_bpc,
> > +		uint32_t flags)
> > +{
> > +	igt_output_t *output;
> > +	igt_display_t *display = &data->display;
> > +	enum pipe pipe;
> > +	unsigned int max_bpc;
> > +	int valid_outputs = 0;
> > +
> > +	for_each_pipe_with_valid_output(display, pipe, output) {
> 
> Not sure if we should test on so many combinations, it may be overkill I
> believe
> and waste CI execution time. May be we can limit it to just 1 pipe as we
> have done for
> plane. Generally the same logic is applied on all pipes so if it works on
> 1 pipe, should work
> on others as well.
[Bhanu] I'll limit the execution to single pipe.
> 
> > +		if (!has_max_bpc(output))
> > +			continue;
> > +
> > +		max_bpc = get_output_bpc(data, output);
> > +		if(max_bpc < output_bpc)
> > +			continue;
> > +
> > +		igt_dynamic_f("%s-on-pipe-%s", output->name,
> > kmstest_pipe_name(pipe))
> > +			if (igt_pipe_connector_valid(pipe, output))
> > +				test_dithering(data, pipe, output, fb_bpc,
> > +					       fb_format, output_bpc, flags);
> > +
> > +		valid_outputs++;
> > +	}
> > +
> > +	igt_require_f(valid_outputs, "No connector found with MAX BPC
> > connector property. (or) "
> > +				     "No connector found with Max Panel BPC (%d)
> > >= %d.\n",
> > +		      max_bpc, output_bpc);
> > +}
> > +
> > +igt_main
> > +{
> > +	struct {
> > +		int bpc;
> > +		int format;
> > +	} fb_formats[] = {
> > +		{ IGT_FRAME_BUFFER_BPC_8, DRM_FORMAT_RGB888 },
> > +		{ IGT_FRAME_BUFFER_BPC_10, DRM_FORMAT_XRGB2101010 },
> > +		{ IGT_FRAME_BUFFER_BPC_16, DRM_FORMAT_XRGB16161616F },
> > +	};
> > +	int output_bpc[] = {
> > +		IGT_CONNECTOR_BPC_6,
> > +		IGT_CONNECTOR_BPC_8,
> > +		IGT_CONNECTOR_BPC_10
> > +	};
> 
> I think you can keep these out of main and have them defined as static.
[Bhanu] No other function is directly accessing these structs, I think it can be ok to keep inside the main().
> 
> Also, please test this out on real monitors and check the behavior.
[Bhanu] I'll run the CI on this patch along with kernel patches (IGT+kernel), 
Meanwhile, can you please review the kernel patches as well?
https://patchwork.freedesktop.org/series/79664/ 
> 
> > +	int i, j;
> > +	data_t data = { 0 };
> > +
> > +	igt_fixture {
> > +		data.drm_fd = drm_open_driver_master(DRIVER_INTEL);
> > +		kmstest_set_vt_graphics_mode();
> > +
> > +		igt_display_require(&data.display, data.drm_fd);
> > +		igt_display_require_output(&data.display);
> > +	}
> > +
> > +	for (i = 0; i < ARRAY_SIZE(fb_formats); i++) {
> > +		for (j = 0; j < ARRAY_SIZE(output_bpc); j++) {
> > +			igt_describe_f("Framebuffer BPC:%d, Panel BPC:%d,
> > Expected Dither:%s\n",
> > +				       fb_formats[i].bpc, output_bpc[j],
> > +				       (fb_formats[i].bpc > output_bpc[j]) ?
> > "Enable": "Disable");
> > +
> > +			igt_subtest_with_dynamic_f("FB-%dBPC-Vs-Panel-
> > %dBPC", fb_formats[i].bpc, output_bpc[j])
> > +				run_dither_test(&data,
> > +						fb_formats[i].bpc,
> > +						fb_formats[i].format,
> > +						output_bpc[j],
> > +						TEST_NONE);
> > +		}
> > +	}
> > +
> > +	igt_fixture {
> > +		igt_display_fini(&data.display);
> > +	}
> > +}
> > diff --git a/tests/meson.build b/tests/meson.build index
> cfe508c4..05a9cfb8
> > 100644
> > --- a/tests/meson.build
> > +++ b/tests/meson.build
> > @@ -27,6 +27,7 @@ test_progs = [
> >  	'kms_cursor_crc',
> >  	'kms_cursor_edge_walk',
> >  	'kms_cursor_legacy',
> > +	'kms_dither',
> >  	'kms_dp_aux_dev',
> >  	'kms_dp_dsc',
> >  	'kms_dp_tiled_display',
> > --
> > 2.20.1
> 



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