drm/i915/display: Modify debugfs for joiner to force n pipes

At the moment, the debugfs for joiner allows only to force enable/disable
pipe joiner for 2 pipes. Modify it to force join 'n' number of pipes,
where n is a valid pipe joiner configuration.
This will help in case of ultra joiner where 4 pipes are joined.

v2:
-Fix commit message to state that only valid joiner config can be
forced. (Suraj)
-Rename the identifiers to have INTEL_BIG/NONE_JOINER_PIPES. (Suraj)
v3:
-Avoid enum for joiner pipe counts, use bare numbers for better
readability. (Ville)
-Remove redundant prints from debugfs. (Ville)
v4: Return -EINVAL if joiner forced to an invalid value.
v5: Remove extra debug message. (Ville)
v6: Minor fix in switch case. (Ville)

Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240926134322.3728021-4-ankit.k.nautiyal@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_display_debugfs.c b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
index c38023b43682e0ec22b8ba4e5c0b240af867b5fa..ae3715f0f1d8e1b072124bd1cc690d7bd3cfe324 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_display_debugfs.c
+++ b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
@@ -1316,6 +1316,59 @@ static int intel_crtc_pipe_show(struct seq_file *m, void *unused)
 }
 DEFINE_SHOW_ATTRIBUTE(intel_crtc_pipe);
 
+static int i915_joiner_show(struct seq_file *m, void *data)
+{
+       struct intel_connector *connector = m->private;
+
+       seq_printf(m, "%d\n", connector->force_joined_pipes);
+
+       return 0;
+}
+
+static ssize_t i915_joiner_write(struct file *file,
+                                const char __user *ubuf,
+                                size_t len, loff_t *offp)
+{
+       struct seq_file *m = file->private_data;
+       struct intel_connector *connector = m->private;
+       int force_joined_pipes = 0;
+       int ret;
+
+       if (len == 0)
+               return 0;
+
+       ret = kstrtoint_from_user(ubuf, len, 0, &force_joined_pipes);
+       if (ret < 0)
+               return ret;
+
+       switch (force_joined_pipes) {
+       case 0:
+       case 2:
+               connector->force_joined_pipes = force_joined_pipes;
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       *offp += len;
+
+       return len;
+}
+
+static int i915_joiner_open(struct inode *inode, struct file *file)
+{
+       return single_open(file, i915_joiner_show, inode->i_private);
+}
+
+static const struct file_operations i915_joiner_fops = {
+       .owner = THIS_MODULE,
+       .open = i915_joiner_open,
+       .read = seq_read,
+       .llseek = seq_lseek,
+       .release = single_release,
+       .write = i915_joiner_write
+};
+
 /**
  * intel_connector_debugfs_add - add i915 specific connector debugfs files
  * @connector: pointer to a registered intel_connector
@@ -1365,8 +1418,8 @@ void intel_connector_debugfs_add(struct intel_connector *connector)
        if ((connector_type == DRM_MODE_CONNECTOR_DisplayPort ||
             connector_type == DRM_MODE_CONNECTOR_eDP) &&
            intel_dp_has_joiner(intel_attached_dp(connector))) {
-               debugfs_create_bool("i915_bigjoiner_force_enable", 0644, root,
-                                   &connector->force_bigjoiner_enable);
+               debugfs_create_file("i915_joiner_force_enable", 0644, root,
+                                   connector, &i915_joiner_fops);
        }
 
        if (connector_type == DRM_MODE_CONNECTOR_DSI ||

diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
index 7ff97e5b83dd5e8d07d307ef1a27c1008fae25ea..7fb3eeb0e0f291dcbadc53c7640ae9575a971fb1 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_display_types.h
+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
@@ -524,7 +524,7 @@ struct intel_connector {
 
        struct intel_dp *mst_port;
 
-       bool force_bigjoiner_enable;
+       int force_joined_pipes;
 
        struct {
                struct drm_dp_aux *dsc_decompression_aux;

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 16dc1d26d2a2531aecbb9722a8db4b3a46f0c032..a1a64758d30d17749586cdf29e5f4537c3a3280d 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -1274,7 +1274,7 @@ bool intel_dp_need_joiner(struct intel_dp *intel_dp,
                return false;
 
        return clock > i915->display.cdclk.max_dotclk_freq || hdisplay > 5120 ||
-              connector->force_bigjoiner_enable;
+              connector->force_joined_pipes == 2;
 }
 
 bool intel_dp_has_dsc(const struct intel_connector *connector)