On Mon, 09 Oct 2023, Stanislav Lisovskiy <stanislav.lisovskiy@xxxxxxxxx> wrote:
> For validation purposes, it might be useful to be able to
> force Bigjoiner mode, even if current dotclock/resolution
> do not require that.
> Lets add such to option to debugfs.
>
> v2: - Apparently intel_dp_need_bigjoiner can't be used, when
> debugfs entry is created so lets just check manually
> the DISPLAY_VER.
>
> Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@xxxxxxxxx>
> ---
> .../drm/i915/display/intel_display_debugfs.c | 71 +++++++++++++++++++
> .../drm/i915/display/intel_display_types.h | 2 +
> drivers/gpu/drm/i915/display/intel_dp.c | 6 +-
> 3 files changed, 78 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display_debugfs.c b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
> index f6d7c4d45fae..c806957cb902 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_debugfs.c
> +++ b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
> @@ -1399,6 +1399,35 @@ out: drm_modeset_unlock(&dev->mode_config.connection_mutex);
> return ret;
> }
>
> +static int i915_bigjoiner_enable_show(struct seq_file *m, void *data)
> +{
> + struct drm_connector *connector = m->private;
struct intel_connector *connector, please. Yeah, this is copy-paste from
other files, but they should be changed too.
> + struct drm_device *dev = connector->dev;
struct drm_i915_private *i915, please.
> + struct drm_crtc *crtc;
> + struct intel_encoder *encoder = intel_attached_encoder(to_intel_connector(connector));
> + struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
> + int ret;
> +
> + if (!encoder)
> + return -ENODEV;
> +
> + ret = drm_modeset_lock_single_interruptible(&dev->mode_config.connection_mutex);
> + if (ret)
> + return ret;
Why does show need locking but write doesn't?
> +
> + crtc = connector->state->crtc;
> + if (connector->status != connector_status_connected || !crtc) {
> + ret = -ENODEV;
> + goto out;
> + }
I guess because of the above, but... do we need it? Or is this just
copy-pasted from some other debugfs files, which copy-pasted from other
debugfs files, which... ;)
> +
> + seq_printf(m, "Bigjoiner enable: %d\n", intel_dp->force_bigjoiner_en);
> +
> +out: drm_modeset_unlock(&dev->mode_config.connection_mutex);
> +
> + return ret;
> +}
> +
> static ssize_t i915_dsc_output_format_write(struct file *file,
> const char __user *ubuf,
> size_t len, loff_t *offp)
> @@ -1420,12 +1449,39 @@ static ssize_t i915_dsc_output_format_write(struct file *file,
> return len;
> }
>
> +static ssize_t i915_bigjoiner_enable_fops_write(struct file *file,
> + const char __user *ubuf,
> + size_t len, loff_t *offp)
> +{
> + struct drm_connector *connector =
> + ((struct seq_file *)file->private_data)->private;
I think this reads better with
struct seq_file *m = file->private_data;
struct intel_connector *connector = m->private;
> + struct intel_encoder *encoder = intel_attached_encoder(to_intel_connector(connector));
> + struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
> + int bigjoiner_en = 0;
> + int ret;
> +
> + ret = kstrtoint_from_user(ubuf, len, 0, &bigjoiner_en);
> + if (ret < 0)
> + return ret;
If it's a bool, why kstrtoint? Yeah, because copy-paste, but why keep
percolating the same mistakes?
> +
> + intel_dp->force_bigjoiner_en = bigjoiner_en;
> + *offp += len;
> +
> + return len;
> +}
> +
> static int i915_dsc_output_format_open(struct inode *inode,
> struct file *file)
> {
> return single_open(file, i915_dsc_output_format_show, inode->i_private);
> }
>
> +static int i915_bigjoiner_enable_open(struct inode *inode,
> + struct file *file)
> +{
> + return single_open(file, i915_bigjoiner_enable_show, inode->i_private);
> +}
> +
> static const struct file_operations i915_dsc_output_format_fops = {
> .owner = THIS_MODULE,
> .open = i915_dsc_output_format_open,
> @@ -1435,6 +1491,15 @@ static const struct file_operations i915_dsc_output_format_fops = {
> .write = i915_dsc_output_format_write
> };
>
> +static const struct file_operations i915_bigjoiner_enable_fops = {
> + .owner = THIS_MODULE,
> + .open = i915_bigjoiner_enable_open,
> + .read = seq_read,
> + .llseek = seq_lseek,
> + .release = single_release,
> + .write = i915_bigjoiner_enable_fops_write
> +};
> +
> /*
> * Returns the Current CRTC's bpc.
> * Example usage: cat /sys/kernel/debug/dri/0/crtc-0/i915_current_bpc
> @@ -1514,6 +1579,12 @@ void intel_connector_debugfs_add(struct intel_connector *intel_connector)
> connector, &i915_dsc_output_format_fops);
> }
>
> + if (DISPLAY_VER(dev_priv) >= 11 &&
> + connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort) {
> + debugfs_create_file("i915_bigjoiner_force_enable", 0644, root,
> + connector, &i915_bigjoiner_enable_fops);
All of these should just pass struct intel_connector.
> + }
> +
> if (connector->connector_type == DRM_MODE_CONNECTOR_DSI ||
> connector->connector_type == DRM_MODE_CONNECTOR_eDP ||
> connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort ||
> diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
> index 8d8b2f8d37a9..ecec8a25838e 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> @@ -1753,6 +1753,8 @@ struct intel_dp {
> bool is_mst;
> int active_mst_links;
>
> + bool force_bigjoiner_en;
No need to try to shorten this, just spell out force_bigjoiner_enable.
> +
> /* connector directly attached - won't be use for modeset in mst world */
> struct intel_connector *attached_connector;
>
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index f0f43aeabd21..7e553cb7ecbb 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -1153,7 +1153,11 @@ bool intel_dp_need_bigjoiner(struct intel_dp *intel_dp,
> if (!intel_dp_can_bigjoiner(intel_dp))
> return false;
>
> - return clock > i915->max_dotclk_freq || hdisplay > 5120;
> + if (intel_dp->force_bigjoiner_en)
> + drm_dbg_kms(&i915->drm, "Forcing bigjoiner mode");
Missing \n.
> +
> + return clock > i915->max_dotclk_freq || hdisplay > 5120 ||
> + intel_dp->force_bigjoiner_en;
> }
>
> static enum drm_mode_status
--
Jani Nikula, Intel
