drm/msm/debugfs: Add display/kms state snapshot

Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20211215174524.1742389-4-robdclark@gmail.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>

drivers/gpu/drm/msm/msm_debugfs.c

@@ -15,6 +15,11 @@
 #include "msm_gpu.h"
 #include "msm_kms.h"
 #include "msm_debugfs.h"
+#include "disp/msm_disp_snapshot.h"
+
+/*
+ * GPU Snapshot:
+ */
 
 struct msm_gpu_show_priv {
 	struct msm_gpu_state *state;
@@ -109,6 +114,73 @@ static const struct file_operations msm_gpu_fops = {
 	.release = msm_gpu_release,
 };
 
+/*
+ * Display Snapshot:
+ */
+
+static int msm_kms_show(struct seq_file *m, void *arg)
+{
+	struct drm_printer p = drm_seq_file_printer(m);
+	struct msm_disp_state *state = m->private;
+
+	msm_disp_state_print(state, &p);
+
+	return 0;
+}
+
+static int msm_kms_release(struct inode *inode, struct file *file)
+{
+	struct seq_file *m = file->private_data;
+	struct msm_disp_state *state = m->private;
+
+	msm_disp_state_free(state);
+
+	return single_release(inode, file);
+}
+
+static int msm_kms_open(struct inode *inode, struct file *file)
+{
+	struct drm_device *dev = inode->i_private;
+	struct msm_drm_private *priv = dev->dev_private;
+	struct msm_disp_state *state;
+	int ret;
+
+	if (!priv->kms)
+		return -ENODEV;
+
+	ret = mutex_lock_interruptible(&priv->kms->dump_mutex);
+	if (ret)
+		return ret;
+
+	state = msm_disp_snapshot_state_sync(priv->kms);
+
+	mutex_unlock(&priv->kms->dump_mutex);
+
+	if (IS_ERR(state)) {
+		return PTR_ERR(state);
+	}
+
+	ret = single_open(file, msm_kms_show, state);
+	if (ret) {
+		msm_disp_state_free(state);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct file_operations msm_kms_fops = {
+	.owner = THIS_MODULE,
+	.open = msm_kms_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = msm_kms_release,
+};
+
+/*
+ * Other debugfs:
+ */
+
 static unsigned long last_shrink_freed;
 
 static int
@@ -239,6 +311,9 @@ void msm_debugfs_init(struct drm_minor *minor)
 	debugfs_create_file("gpu", S_IRUSR, minor->debugfs_root,
 		dev, &msm_gpu_fops);
 
+	debugfs_create_file("kms", S_IRUSR, minor->debugfs_root,
+		dev, &msm_kms_fops);
+
 	debugfs_create_u32("hangcheck_period_ms", 0600, minor->debugfs_root,
 		&priv->hangcheck_period);