Commit cca912e0 authored by Eryk Brol's avatar Eryk Brol Committed by Alex Deucher
Browse files

drm/amd/display: Add max bpc debugfs 



[Why]
Useful for testing when setting a max bpc value higher than the default
is required

[How]
Allow for reading/writing of the max_requested_bpc property of the
connector

Tested-by: default avatarDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: default avatarEryk Brol <eryk.brol@amd.com>
Signed-off-by: default avatarIlya Bakoulin <Ilya.Bakoulin@amd.com>
Reviewed-by: default avatarMikita Lipski <Mikita.Lipski@amd.com>
Acked-by: default avatarRodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 4cda3243

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c

+152 −1
Original line number Diff line number Diff line
@@ -2152,6 +2152,149 @@ static ssize_t dp_dsc_slice_bpg_offset_read(struct file *f, char __user *buf, 
	return result;

}





/*

 * function description: Read max_requested_bpc property from the connector

 *

 * Access it with the following command:

 *

 *	cat /sys/kernel/debug/dri/0/DP-X/max_bpc

 *

 */

static ssize_t dp_max_bpc_read(struct file *f, char __user *buf,

		size_t size, loff_t *pos)

{

	struct amdgpu_dm_connector *aconnector = file_inode(f)->i_private;

	struct drm_connector *connector = &aconnector->base;

	struct drm_device *dev = connector->dev;

	struct dm_connector_state *state;

	ssize_t result = 0;

	char *rd_buf = NULL;

	char *rd_buf_ptr = NULL;

	const uint32_t rd_buf_size = 10;

	int r;



	rd_buf = kcalloc(rd_buf_size, sizeof(char), GFP_KERNEL);



	if (!rd_buf)

		return -ENOMEM;



	mutex_lock(&dev->mode_config.mutex);

	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);



	if (connector->state == NULL)

		goto unlock;



	state = to_dm_connector_state(connector->state);



	rd_buf_ptr = rd_buf;

	snprintf(rd_buf_ptr, rd_buf_size,

		"%u\n",

		state->base.max_requested_bpc);



	while (size) {

		if (*pos >= rd_buf_size)

			break;



		r = put_user(*(rd_buf + result), buf);

		if (r) {

			result = r; /* r = -EFAULT */

			goto unlock;

		}

		buf += 1;

		size -= 1;

		*pos += 1;

		result += 1;

	}

unlock:

	drm_modeset_unlock(&dev->mode_config.connection_mutex);

	mutex_unlock(&dev->mode_config.mutex);

	kfree(rd_buf);

	return result;

}





/*

 * function description: Set max_requested_bpc property on the connector

 *

 * This function will not force the input BPC on connector, it will only

 * change the max value. This is equivalent to setting max_bpc through

 * xrandr.

 *

 * The BPC value written must be >= 6 and <= 16. Values outside of this

 * range will result in errors.

 *

 * BPC values:

 *	0x6 - 6 BPC

 *	0x8 - 8 BPC

 *	0xa - 10 BPC

 *	0xc - 12 BPC

 *	0x10 - 16 BPC

 *

 * Write the max_bpc in the following way:

 *

 * echo 0x6 > /sys/kernel/debug/dri/0/DP-X/max_bpc

 *

 */

static ssize_t dp_max_bpc_write(struct file *f, const char __user *buf,

				     size_t size, loff_t *pos)

{

	struct amdgpu_dm_connector *aconnector = file_inode(f)->i_private;

	struct drm_connector *connector = &aconnector->base;

	struct dm_connector_state *state;

	struct drm_device *dev = connector->dev;

	char *wr_buf = NULL;

	uint32_t wr_buf_size = 42;

	int max_param_num = 1;

	long param[1] = {0};

	uint8_t param_nums = 0;



	if (size == 0)

		return -EINVAL;



	wr_buf = kcalloc(wr_buf_size, sizeof(char), GFP_KERNEL);



	if (!wr_buf) {

		DRM_DEBUG_DRIVER("no memory to allocate write buffer\n");

		return -ENOSPC;

	}



	if (parse_write_buffer_into_params(wr_buf, size,

					   (long *)param, buf,

					   max_param_num,

					   &param_nums)) {

		kfree(wr_buf);

		return -EINVAL;

	}



	if (param_nums <= 0) {

		DRM_DEBUG_DRIVER("user data not be read\n");

		kfree(wr_buf);

		return -EINVAL;

	}



	if (param[0] < 6 || param[0] > 16) {

		DRM_DEBUG_DRIVER("bad max_bpc value\n");

		kfree(wr_buf);

		return -EINVAL;

	}



	mutex_lock(&dev->mode_config.mutex);

	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);



	if (connector->state == NULL)

		goto unlock;



	state = to_dm_connector_state(connector->state);

	state->base.max_requested_bpc = param[0];

unlock:

	drm_modeset_unlock(&dev->mode_config.connection_mutex);

	mutex_unlock(&dev->mode_config.mutex);



	kfree(wr_buf);

	return size;

}



DEFINE_SHOW_ATTRIBUTE(dp_dsc_fec_support);

DEFINE_SHOW_ATTRIBUTE(dmub_fw_state);

DEFINE_SHOW_ATTRIBUTE(dmub_tracebuffer);
@@ -2263,6 +2406,13 @@ static const struct file_operations dp_dpcd_data_debugfs_fops = { 
	.llseek = default_llseek

};



static const struct file_operations dp_max_bpc_debugfs_fops = {

	.owner = THIS_MODULE,

	.read = dp_max_bpc_read,

	.write = dp_max_bpc_write,

	.llseek = default_llseek

};



static const struct {

	char *name;

	const struct file_operations *fops;
@@ -2285,7 +2435,8 @@ static const struct { 
		{"dsc_pic_height", &dp_dsc_pic_height_debugfs_fops},

		{"dsc_chunk_size", &dp_dsc_chunk_size_debugfs_fops},

		{"dsc_slice_bpg", &dp_dsc_slice_bpg_offset_debugfs_fops},

		{"dp_dsc_fec_support", &dp_dsc_fec_support_fops}

		{"dp_dsc_fec_support", &dp_dsc_fec_support_fops},

		{"max_bpc", &dp_max_bpc_debugfs_fops}

};



#ifdef CONFIG_DRM_AMD_DC_HDCP