[igt-dev] [PATCH i-g-t v2] test/amdgpu: Add DP mst test

Petri Latvala petri.latvala at intel.com
Tue Aug 2 11:16:42 UTC 2022


On Tue, Aug 02, 2022 at 06:56:34PM +0800, Wayne Lin wrote:
> [Why & How]
> Add new igt test amd_mst for DP mst feature.
> 
> MST (Multi-Stream Transport) is the feature introduced from DP 1.2.
> By mst, source can transport multiple streams to different stream
> sinks through the same DP Tx.
> 
> This new igt test "amd_mst" validate mst feature from two perspectives:
> 
> * Trigger hotplug via debugfs to see whether all mst end sinks
>   successfully go through mst light up procedure
> * Check if all mst end sinks successfully go through mst light up
>   procedure after suspend-resume
> 
> This tool is developed under the setup below:
> * 2xFHD monitors connected after the 3D club mst hub (model CSV-7300).
>   Upstream port of 3D club hub is connected directly to ASIC DP port.
> 
> v2:
> - Revise the commit message to describe the hardware setup while
>   developing this tool.
> - Rename is_mst_connector to mst_roles
> - Remove unnecessary variable/space/brackets
> - Add more descriptions for MST progress status
> - Add option to specify the delay before checking MST progress status
> 
> Signed-off-by: Wayne Lin <Wayne.Lin at amd.com>
> ---
>  lib/igt_amd.c            | 157 +++++++++++++++++++
>  lib/igt_amd.h            |  47 ++++++
>  tests/amdgpu/amd_mst.c   | 316 +++++++++++++++++++++++++++++++++++++++
>  tests/amdgpu/meson.build |   1 +
>  4 files changed, 521 insertions(+)
>  create mode 100644 tests/amdgpu/amd_mst.c
> 
> diff --git a/lib/igt_amd.c b/lib/igt_amd.c
> index bef9c193..7ad70dc8 100644
> --- a/lib/igt_amd.c
> +++ b/lib/igt_amd.c
> @@ -1175,3 +1175,160 @@ bool igt_amd_set_visual_confirm(int drm_fd, enum amdgpu_debug_visual_confirm opt
>  
>  	return res;
>  }
> +
> +/**
> + * igt_amd_output_has_mst: check if connector has MST debugfs entries
> + * @drm_fd: DRM file descriptor
> + * @connector_name: The connector's name, on which we're reading the status
> + */
> +static bool igt_amd_output_has_mst(int drm_fd, char *connector_name)
> +{
> +	return igt_amd_output_has_debugfs(drm_fd, connector_name, DEBUGFS_MST_IS_MST_CONNECTOR) &
> +			igt_amd_output_has_debugfs(drm_fd, connector_name, DEBUGFS_MST_PROGRESS_STATUS);
> +}
> +
> +/**
> + * igt_amd_require_mst: Checks if connectors have mst debugfs entries
> + * @display: A pointer to an #igt_display_t structure
> + * @drm_fd: DRM file descriptor
> + *
> + * Checks if the AMDGPU driver supports the 'is_mst_connector'
> + * and 'mst_progress_status' entry for mst. Skip test if there
> + * are no relevant debugfs entries.
> + */
> +void igt_amd_require_mst(igt_display_t *display, int drm_fd)
> +{
> +	igt_output_t *output;
> +
> +	for_each_connected_output(display, output)
> +		if (igt_amd_output_has_mst(drm_fd, output->name))
> +			return;
> +
> +	igt_skip("No MST relevant debugfs support.\n");
> +}
> +
> +/**
> + * igt_amd_get_mst_role: Get the mst role of this output
> + * @drm_fd: DRM file descriptor
> + * @output: the output to be checked
> + *
> + * DRM enumerates a drm connector to each MST output port. This is used to
> + * determine the mst role of this specific output. The mst role in the
> + * mst topology shoule be 'no', 'root', 'branch' and 'end'
> + */
> +enum dp_mst_role igt_amd_get_mst_role(int drm_fd, igt_output_t *output)
> +{
> +	int fd, ret;
> +	char buf[256] = {'\0'};
> +	int i = 0;
> +	enum dp_mst_role role = MST_NONE;
> +
> +	fd = igt_debugfs_connector_dir(drm_fd, output->name, O_RDONLY);
> +	if (fd < 0) {
> +		igt_info("Could not open connector %s debugfs directory\n",
> +			 output->name);
> +		return MST_NONE;
> +	}
> +
> +	if (output->config.connector->connector_type != DRM_MODE_CONNECTOR_DisplayPort)
> +		return MST_NONE;
> +
> +	ret = igt_debugfs_simple_read(fd, DEBUGFS_MST_IS_MST_CONNECTOR, buf, sizeof(buf));
> +	igt_assert_f(ret >= 0, "Reading %s for connector %s failed.\n",
> +		     DEBUGFS_MST_IS_MST_CONNECTOR, output->name);
> +
> +	close(fd);
> +
> +	for (i = 0; i < sizeof(mst_roles)/sizeof(char *); i++) {
> +		if (strstr(buf, mst_roles[i])) {
> +			role = i;
> +			break;
> +		}
> +	}
> +
> +	if (role != MST_NONE)
> +		igt_info("Connector %s: is a mst %s", output->name, buf);

You're missing a newline from this print.


-- 
Petri Latvala


> +	else
> +		igt_info("Connector %s: is not a mst device\n", output->name);
> +
> +	return role;
> +}
> +
> +/**
> + * igt_amd_get_mst_progress_status: Get the mst progress status of a mst device
> + * @drm_fd: DRM file descriptor
> + * @output: the output to be checked
> + *
> + * Get the mst progress status of this specific output. The mst progress status
> + * is indicated by:
> + * MST_PROBE - drm connector got detected by LINK_ADDRESS sideband msg.
> + * MST_REMOTE_EDID - successfully read out edid by REMOTE_I2C_READ sideband msg.
> + * MST_ALLOCATE_NEW_PAYLOAD - suuccessfully allocate time slots for the stream.
> + * MST_CLEAR_ALLOCATED_PAYLOAD - successfully clean out allocated time slots.
> + */
> +uint8_t igt_amd_get_mst_progress_status(int drm_fd, igt_output_t *output)
> +{
> +	int fd, ret;
> +	char buf[256] = {'\0'};
> +	int idx = 0;
> +	char *token_end;
> +	uint8_t status = MST_STATUS_DEFAULT;
> +
> +	fd = igt_debugfs_connector_dir(drm_fd, output->name, O_RDONLY);
> +	if (fd < 0) {
> +		igt_info("Could not open connector %s debugfs directory\n",
> +			 output->name);
> +		return MST_STATUS_DEFAULT;
> +	}
> +
> +	if (output->config.connector->connector_type != DRM_MODE_CONNECTOR_DisplayPort)
> +		return MST_STATUS_DEFAULT;
> +
> +	ret = igt_debugfs_simple_read(fd, DEBUGFS_MST_PROGRESS_STATUS, buf, sizeof(buf));
> +	igt_assert_f(ret >= 0, "Reading %s for connector %s failed.\n",
> +		     DEBUGFS_MST_PROGRESS_STATUS, output->name);
> +
> +	close(fd);
> +
> +	/* Parse values read from file. */
> +	for (char *token = strtok_r(buf, "\n", &token_end);
> +	     token != NULL;
> +	     token = strtok_r(NULL, "\n", &token_end), idx++)
> +	{
> +		if (strstr(token, "not") == NULL)
> +			status |= BIT(idx);
> +	}
> +
> +	return status;
> +}
> +
> +/**
> + * mst_trigger_hotplug: Trigger mst hotplug
> + * @drm_fd: DRM file descriptor
> + * @output: #igt_output_t to check.
> + *
> + * Trigger soft hotplug on mst connector. Caller should make sure the
> + * passed output is mst root by igt_amd_get_mst_role(). We can't generate
> + * soft hotplug on mst end device.
> + */
> +void mst_trigger_hotplug(int drm_fd, igt_output_t *output)
> +{
> +	int fd, hpd_fd;
> +	int wr_len;
> +	const char *enable_hpd = "1", *disable_hpd = "0";
> +
> +	fd = igt_debugfs_connector_dir(drm_fd, output->name, O_RDONLY);
> +	igt_assert(fd >= 0);
> +	hpd_fd = openat(fd, DEBUGFS_HPD_TRIGGER, O_WRONLY);
> +	close(fd);
> +	igt_assert(hpd_fd >= 0);
> +
> +	wr_len = write(hpd_fd, disable_hpd, strlen(disable_hpd));
> +	igt_assert_eq(wr_len, strlen(disable_hpd));
> +
> +	sleep(3);
> +
> +	wr_len = write(hpd_fd, enable_hpd, strlen(enable_hpd));
> +	igt_assert_eq(wr_len, strlen(enable_hpd));
> +	close(hpd_fd);
> +}
> \ No newline at end of file
> diff --git a/lib/igt_amd.h b/lib/igt_amd.h
> index 428bfe6f..2d54ddc3 100644
> --- a/lib/igt_amd.h
> +++ b/lib/igt_amd.h
> @@ -52,6 +52,12 @@
>  /* amdgpu DM interface entries */
>  #define DEBUGFS_DM_VISUAL_CONFIRM "amdgpu_dm_visual_confirm"
>  
> +/* mst related read only status*/
> +#define DEBUGFS_MST_IS_MST_CONNECTOR "is_mst_connector"
> +#define DEBUGFS_MST_PROGRESS_STATUS "mst_progress_status"
> +
> +#define BIT(x) (1ul <<(x))
> +
>  enum amd_dsc_clock_force {
>  	DSC_AUTOMATIC = 0,
>  	DSC_FORCE_ON,
> @@ -131,6 +137,41 @@ enum amdgpu_debug_visual_confirm {
>  	VISUAL_CONFIRM_SWIZZLE	= 9
>  };
>  
> +/*
> + * Enumeration of the role in MST topology:
> + * MST_NONE - drm connector is not in a MST topology
> + * MST_ROOT - the output DP port locates at stream source.
> + * MST_BRANCH - the intermdediate node of a path from root to leaf within a mst topology
> + * MST_END - the leaf node of a mst topology
> + */
> +enum dp_mst_role {
> +	MST_NONE = 0,
> +	MST_ROOT,
> +	MST_BRANCH,
> +	MST_END,
> +};
> +
> +static const char *const mst_roles[] = {
> +    "no",
> +    "root",
> +    "branch",
> +    "end",
> +};
> +
> +/*
> + * Enumeration of MST progress state. The bit order should align
> + * with the 'enum mst_progress_statusto' in amdgpu_dm.h of
> + * upstreamed amdgpu kernel driver
> + */
> +enum mst_progress_status {
> +	MST_STATUS_DEFAULT = 0,
> +	MST_PROBE = BIT(0),
> +	MST_REMOTE_EDID = BIT(1),
> +	MST_ALLOCATE_NEW_PAYLOAD = BIT(2),
> +	MST_CLEAR_ALLOCATED_PAYLOAD = BIT(3),
> +	NUM_MST_STATUS = 4,
> +};
> +
>  uint32_t igt_amd_create_bo(int fd, uint64_t size);
>  void *igt_amd_mmap_bo(int fd, uint32_t handle, uint64_t size, int prot);
>  unsigned int igt_amd_compute_offset(unsigned int* swizzle_pattern,
> @@ -192,4 +233,10 @@ int  igt_amd_read_psr_state(int drm_fd, char *connector_name);
>  bool igt_amd_has_visual_confirm(int drm_fd);
>  int  igt_amd_get_visual_confirm(int drm_fd);
>  bool igt_amd_set_visual_confirm(int drm_fd, enum amdgpu_debug_visual_confirm option);
> +
> +/* DP MST debugfs helpers*/
> +void igt_amd_require_mst(igt_display_t *display, int drm_fd);
> +enum dp_mst_role igt_amd_get_mst_role(int drm_fd, igt_output_t *output);
> +uint8_t igt_amd_get_mst_progress_status(int drm_fd, igt_output_t *output);
> +void mst_trigger_hotplug(int drm_fd, igt_output_t *output);
>  #endif /* IGT_AMD_H */
> diff --git a/tests/amdgpu/amd_mst.c b/tests/amdgpu/amd_mst.c
> new file mode 100644
> index 00000000..def4edbc
> --- /dev/null
> +++ b/tests/amdgpu/amd_mst.c
> @@ -0,0 +1,316 @@
> +/*
> + * Copyright 2022 Advanced Micro Devices, Inc.
> + *
> + * 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 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.
> + */
> +
> +#include "igt.h"
> +#include "igt_amd.h"
> +
> +IGT_TEST_DESCRIPTION("This igt test validates DP MST feature by:"
> +	"1. Check each mst end sink successfully go through mst light up procedure"
> +	"after hotplug root branch."
> +	"2. Check each mst end sink successfully go through mst light up procedure"
> +	"after suspend-resume");
> +
> +/* Maximum pipes on any AMD ASIC. */
> +#define MAX_PIPES 6
> +
> +typedef struct data {
> +	igt_display_t display;
> +	igt_plane_t *primary[MAX_PIPES];
> +	igt_output_t *output_mst_end[MAX_PIPES];
> +	igt_output_t *output_mst_root[MAX_PIPES];
> +	igt_pipe_t *pipe[MAX_PIPES];
> +	igt_fb_t ref_fb[MAX_PIPES];
> +	drmModeModeInfo mode[MAX_PIPES];
> +	enum pipe pipe_id[MAX_PIPES];
> +	int w[MAX_PIPES];
> +	int h[MAX_PIPES];
> +	int fd;
> +	int num_mst_end;
> +	int usr_num_mst_end;
> +	int delay_for_progress;
> +} data_t;
> +
> +static void test_init(data_t *data)
> +{
> +	igt_display_t *display = &data->display;
> +	int i, m, n, max_pipes = display->n_pipes;
> +	enum dp_mst_role role;
> +	drmModeConnector *conn;
> +
> +	for_each_pipe(display, i) {
> +		data->pipe_id[i] = PIPE_A + i;
> +		data->pipe[i] = &data->display.pipes[data->pipe_id[i]];
> +		data->primary[i] = igt_pipe_get_plane_type(
> +			data->pipe[i], DRM_PLANE_TYPE_PRIMARY);
> +	}
> +
> +	/* Find mst connected root/end connector*/
> +	for (i = 0, n = 0, m = 0, data->num_mst_end = 0;
> +		i < display->n_outputs && n < max_pipes && m < max_pipes; i++) {
> +		igt_output_t *output = &display->outputs[i];
> +
> +		conn = output->config.connector;
> +		if (conn->connector_type != DRM_MODE_CONNECTOR_DisplayPort)
> +			continue;
> +
> +		role = igt_amd_get_mst_role(data->fd, output);
> +
> +		switch(role) {
> +			case MST_ROOT:
> +				data->output_mst_root[n++] = output;
> +				break;
> +			case MST_END:
> +				if (!igt_output_is_connected(output))
> +					continue;
> +				data->output_mst_end[m] = output;
> +				igt_assert(kmstest_get_connector_default_mode(
> +				data->fd, output->config.connector, &data->mode[m]));
> +
> +				data->w[m] = data->mode[m].hdisplay;
> +				data->h[m] = data->mode[m].vdisplay;
> +				m++;
> +				data->num_mst_end++;
> +				break;
> +			default:
> +				continue;
> +				break;
> +		}
> +	}
> +
> +	igt_require(data->output_mst_root[0]);
> +	igt_require(data->output_mst_end[0]);
> +	if (data->usr_num_mst_end)
> +		igt_assert_eq(data->usr_num_mst_end, data->num_mst_end);
> +	igt_display_reset(display);
> +}
> +
> +static void test_fini(data_t *data)
> +{
> +	igt_display_t *display = &data->display;
> +
> +	igt_display_reset(display);
> +	igt_display_commit_atomic(display, DRM_MODE_ATOMIC_ALLOW_MODESET, 0);
> +}
> +
> +static bool show_mst_status_result(igt_output_t *output, uint8_t status)
> +{
> +	uint8_t bit_idx = 0;
> +	bool result = true;
> +
> +	igt_info("Connector:%s mst progress status:\n", output->name);
> +
> +	for (bit_idx = 0; bit_idx < NUM_MST_STATUS; bit_idx++) {
> +		switch(BIT(bit_idx)) {
> +			case MST_PROBE:
> +				if ((status & MST_PROBE) == MST_STATUS_DEFAULT)
> +					result = false;
> +				igt_info("Probe:%s\n", (status & MST_PROBE) ? "PASS" : "FAIL");
> +				break;
> +			case MST_REMOTE_EDID:
> +				if ((status & MST_REMOTE_EDID) == MST_STATUS_DEFAULT)
> +					result = false;
> +				igt_info("Remote EDID:%s\n", (status & MST_REMOTE_EDID) ? "PASS" : "FAIL");
> +				break;
> +			case MST_ALLOCATE_NEW_PAYLOAD:
> +				if ((status & MST_ALLOCATE_NEW_PAYLOAD) == MST_STATUS_DEFAULT)
> +					result = false;
> +				igt_info("Allocate new payload:%s\n",
> +					(status & MST_ALLOCATE_NEW_PAYLOAD) ? "PASS" : "FAIL");
> +				break;
> +			default:
> +				break;
> +		}
> +	}
> +
> +	return result;
> +}
> +
> +static void reset_resource(data_t *data)
> +{
> +	igt_display_reset(&data->display);
> +	igt_display_fini(&data->display);
> +	close(data->fd);
> +
> +	memset(data->primary, 0, sizeof(igt_plane_t *)*MAX_PIPES);
> +	memset(data->output_mst_end, 0, sizeof(igt_output_t *)*MAX_PIPES);
> +	memset(data->output_mst_root, 0, sizeof(igt_output_t *)*MAX_PIPES);
> +	memset(data->pipe, 0, sizeof(igt_pipe_t *)*MAX_PIPES);
> +	memset(data->mode, 0, sizeof(drmModeModeInfo)*MAX_PIPES);
> +	memset(data->pipe_id, 0, sizeof(enum pipe)*MAX_PIPES);
> +	memset(data->w, 0, sizeof(int)*MAX_PIPES);
> +	memset(data->h, 0, sizeof(int)*MAX_PIPES);
> +
> +	data->fd = drm_open_driver_master(DRIVER_AMDGPU);
> +	igt_display_require(&data->display, data->fd);
> +}
> +
> +static void set_up_streams(data_t *data)
> +{
> +	igt_output_t *output;
> +	int i;
> +
> +	for (i = 0; i < MAX_PIPES; i++) {
> +		output = data->output_mst_end[i];
> +		if (!output || !igt_output_is_connected(output))
> +			continue;
> +
> +		igt_create_pattern_fb(data->fd, data->w[i], data->h[i],
> +				      DRM_FORMAT_XRGB8888, 0, &data->ref_fb[i]);
> +		igt_output_set_pipe(output, data->pipe_id[i]);
> +		igt_plane_set_fb(data->primary[i], &data->ref_fb[i]);
> +	}
> +	igt_display_commit_atomic(&data->display, DRM_MODE_ATOMIC_ALLOW_MODESET, 0);
> +	sleep(5);
> +}
> +
> +static void validate_mst_progress_result(data_t *data)
> +{
> +	int i = 0;
> +	uint8_t status = 0;
> +	igt_output_t *output;
> +
> +	for (i = 0; i < data->num_mst_end; i++) {
> +		output = data->output_mst_end[i];
> +
> +		if (!output)
> +			continue;
> +
> +		status = igt_amd_get_mst_progress_status(data->fd, output);
> +
> +		/* make sure all mst end device get lit up correctly*/
> +		igt_assert(show_mst_status_result(output, status));
> +	}
> +}
> +
> +static void test_mst_hotplug_basic(data_t *data)
> +{
> +	igt_output_t *output;
> +	int i = 0;
> +
> +	test_init(data);
> +
> +	/* Setup all end mst output */
> +	set_up_streams(data);
> +
> +	/*confirm mst progress is done*/
> +	validate_mst_progress_result(data);
> +
> +	/* Trigger hotplug*/
> +	for (i = 0; i < MAX_PIPES; i++) {
> +		output = data->output_mst_root[i];
> +
> +		if (!output)
> +			continue;
> +
> +		mst_trigger_hotplug(data->fd, output);
> +	}
> +
> +	/* mst connectors are dynamically created/destroyed. Need
> +	 * to free and reallocate resources then commit streams again
> +	 */
> +	reset_resource(data);
> +
> +	test_init(data);
> +
> +	set_up_streams(data);
> +
> +	if (data->delay_for_progress)
> +		sleep(data->delay_for_progress);
> +	else
> +		sleep(5);
> +	/*confirm mst progress status again*/
> +	validate_mst_progress_result(data);
> +
> +	/*do suspend resume*/
> +	igt_system_suspend_autoresume(SUSPEND_STATE_MEM, SUSPEND_TEST_NONE);
> +
> +	if (data->delay_for_progress)
> +		sleep(data->delay_for_progress);
> +	else
> +		sleep(5);
> +
> +	/*confirm mst progress status again*/
> +	validate_mst_progress_result(data);
> +
> +	for (i = 0; i < MAX_PIPES; i++) {
> +		output = data->output_mst_end[i];
> +
> +		if (!output)
> +			continue;
> +
> +		igt_remove_fb(data->fd, &data->ref_fb[i]);
> +	}
> +
> +	test_fini(data);
> +}
> +
> +const char *optstr = "hn:d:";
> +static void usage(const char *name)
> +{
> +	igt_info("Usage: %s options\n", name);
> +	igt_info("-h			Show help\n");
> +	igt_info("-n mst_num	Set how many monitors connected in the mst topology\n");
> +	igt_info("-d delay		Set delay before checking the mst progress status\n");
> +	igt_info("NOTE: if -n is not specified, number of monitors will be detected automatically"
> +		"by current connection status\n");
> +	igt_info("NOTE: if -d is not specified, delay before checking the mst progress status"
> +		"will be set as 5s\n");
> +}
> +
> +int main(int argc, char **argv)
> +{
> +	data_t data;
> +	int c;
> +
> +	igt_skip_on_simulation();
> +
> +	memset(&data, 0, sizeof(data));
> +
> +	data.fd = drm_open_driver_master(DRIVER_AMDGPU);
> +	kmstest_set_vt_graphics_mode();
> +
> +	igt_display_require(&data.display, data.fd);
> +	igt_require(data.display.is_atomic);
> +	igt_display_require_output(&data.display);
> +
> +	igt_amd_require_hpd(&data.display, data.fd);
> +	igt_amd_require_mst(&data.display, data.fd);
> +
> +	while((c = getopt(argc, argv, optstr)) != -1) {
> +		switch(c) {
> +		case 'n':
> +			data.usr_num_mst_end = atoi(optarg);
> +			break;
> +		case 'd':
> +			data.delay_for_progress = atoi(optarg);
> +			break;
> +		case 'h':
> +		default:
> +			usage(argv[0]);
> +			exit(EXIT_SUCCESS);
> +		}
> +	}
> +
> +	test_mst_hotplug_basic(&data);
> +
> +	igt_display_fini(&data.display);
> +}
> diff --git a/tests/amdgpu/meson.build b/tests/amdgpu/meson.build
> index f4a0b9fd..5964c080 100644
> --- a/tests/amdgpu/meson.build
> +++ b/tests/amdgpu/meson.build
> @@ -21,6 +21,7 @@ if libdrm_amdgpu.found()
>  			  'amd_psr',
>  			  'amd_plane',
>  			  'amd_ilr',
> +			  'amd_mst',
>  			]
>  	amdgpu_deps += libdrm_amdgpu
>  endif
> -- 
> 2.25.1
> 


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