[Intel-gfx] [PATCH 50/53] drm/i915/display/dsc: Add Per connector debugfs node for DSC BPP enable

Matt Roper
2021-07-01T20:26:59Z

From: Anusha Srivatsa <anusha.srivatsa@intel.com>

DSC can be supported per DP connector. This patch creates
a per connector debugfs node to expose the Input and
Compressed BPP.

The same node can be used from userspace to force
DSC to a certain BPP.

force_dsc_bpp is written through this debugfs
node to force DSC BPP to all accepted values

Cc: Vandita Kulkarni <vandita.kulkarni@intel.com>
Cc: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Anusha Srivatsa <anusha.srivatsa@intel.com>
Signed-off-by: Patnana Venkata Sai <venkata.sai.patnana@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
---
.../drm/i915/display/intel_display_debugfs.c | 103 +++++++++++++++++-
.../drm/i915/display/intel_display_types.h | 1 +
2 files changed, 103 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 af9e58619667..1805d70ea817 100644
--- a/drivers/gpu/drm/i915/display/intel_display_debugfs.c
+++ b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
@@ -2389,6 +2389,100 @@ static const struct file_operations i915_dsc_fec_support_fops = {
.write = i915_dsc_fec_support_write
};

+static int i915_dsc_bpp_support_show(struct seq_file *m, void *data)
+{
+ struct drm_connector *connector = m->private;
+ struct drm_device *dev = connector->dev;
+ struct drm_crtc *crtc;
+ struct intel_dp *intel_dp;
+ struct drm_modeset_acquire_ctx ctx;
+ struct intel_crtc_state *crtc_state = NULL;
+ int ret = 0;
+ bool try_again = false;
+
+ drm_modeset_acquire_init(&ctx, DRM_MODESET_ACQUIRE_INTERRUPTIBLE);
+
+ do {
+ try_again = false;
+ ret = drm_modeset_lock(&dev->mode_config.connection_mutex,
+ &ctx);
+ if (ret) {
+ ret = -EINTR;
+ break;
+ }
+ crtc = connector->state->crtc;
+ if (connector->status != connector_status_connected || !crtc) {
+ ret = -ENODEV;
+ break;
+ }
+ ret = drm_modeset_lock(&crtc->mutex, &ctx);
+ if (ret == -EDEADLK) {
+ ret = drm_modeset_backoff(&ctx);
+ if (!ret) {
+ try_again = true;
+ continue;
+ }
+ break;
+ } else if (ret) {
+ break;
+ }
+ intel_dp = intel_attached_dp(to_intel_connector(connector));
+ crtc_state = to_intel_crtc_state(crtc->state);
+ seq_printf(m, "Input_BPP: %d\n", crtc_state->pipe_bpp);
+ seq_printf(m, "Compressed_BPP: %d\n",
+ crtc_state->dsc.compressed_bpp);
+ } while (try_again);
+
+ drm_modeset_drop_locks(&ctx);
+ drm_modeset_acquire_fini(&ctx);
+
+ return ret;
+}
+
+static ssize_t i915_dsc_bpp_support_write(struct file *file,
+ const char __user *ubuf,
+ size_t len, loff_t *offp)
+{
+ int dsc_bpp = 0;
+ int ret;
+ struct drm_connector *connector =
+ ((struct seq_file *)file->private_data)->private;
+ struct intel_encoder *encoder = intel_attached_encoder(to_intel_connector(connector));
+ struct drm_i915_private *i915 = to_i915(encoder->base.dev);
+ struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
+
+ if (len == 0)
+ return 0;
+
+ drm_dbg(&i915->drm,
+ "Copied %zu bytes from user to force BPP\n", len);
+
+ ret = kstrtoint_from_user(ubuf, len, 0, &dsc_bpp);
+
+ intel_dp->force_dsc_bpp = dsc_bpp;
+ if (ret < 0)
+ return ret;
+
+ *offp += len;
+ return len;
+}
+
+static int i915_dsc_bpp_support_open(struct inode *inode,
+ struct file *file)
+{
+ return single_open(file, i915_dsc_bpp_support_show,
+ inode->i_private);
+}
+
+static const struct file_operations i915_dsc_bpp_support_fops = {
+ .owner = THIS_MODULE,
+ .open = i915_dsc_bpp_support_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+ .write = i915_dsc_bpp_support_write
+};
+
/**
* intel_connector_debugfs_add - add i915 specific connector debugfs files
* @connector: pointer to a registered drm_connector
@@ -2427,9 +2521,16 @@ int intel_connector_debugfs_add(struct drm_connector *connector)
connector, &i915_hdcp_sink_capability_fops);
}

- if ((DISPLAY_VER(dev_priv) >= 11 || IS_CANNONLAKE(dev_priv)) && ((connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort && !to_intel_connector(connector)->mst_port) || connector->connector_type == DRM_MODE_CONNECTOR_eDP))
+ if ((DISPLAY_VER(dev_priv) >= 11 || IS_CANNONLAKE(dev_priv)) &&
+ ((connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort &&
+ !to_intel_connector(connector)->mst_port) ||
+ connector->connector_type == DRM_MODE_CONNECTOR_eDP)) {
debugfs_create_file("i915_dsc_fec_support", S_IRUGO, root,
connector, &i915_dsc_fec_support_fops);
+ debugfs_create_file("i915_dsc_bpp_support", 0444,
+ root, connector,
+ &i915_dsc_bpp_support_fops);
+ }

/* Legacy panels doesn't lpsp on any platform */
if ((DISPLAY_VER(dev_priv) >= 9 || IS_HASWELL(dev_priv) ||
diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
index 29ae1d9b5abc..00320d89d266 100644
--- a/drivers/gpu/drm/i915/display/intel_display_types.h
+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
@@ -1627,6 +1627,7 @@ struct intel_dp {

/* Display stream compression testing */
bool force_dsc_en;
+ int force_dsc_bpp;

bool hobl_failed;
bool hobl_active;