[media] bdisp: add debug file system

Creates 5 debugfs entries to dump the last HW request, the last HW node
(=command), the HW registers and the recent HW performance (time & fps)
Signed-off-by: Fabien Dessenne <fabien.dessenne@st.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/platform/sti/bdisp/Makefile

 obj-$(CONFIG_VIDEO_STI_BDISP) := bdisp.o
 
-bdisp-objs := bdisp-v4l2.o bdisp-hw.o
+bdisp-objs := bdisp-v4l2.o bdisp-hw.o bdisp-debug.o

drivers/media/platform/sti/bdisp/bdisp-hw.c

@@ -740,6 +740,43 @@ static int bdisp_hw_build_all_nodes(struct bdisp_ctx *ctx)
 	return 0;
 }
 
+/**
+ * bdisp_hw_save_request
+ * @ctx:        device context
+ *
+ * Save a copy of the request and of the built nodes
+ *
+ * RETURNS:
+ * None
+ */
+static void bdisp_hw_save_request(struct bdisp_ctx *ctx)
+{
+	struct bdisp_node **copy_node = ctx->bdisp_dev->dbg.copy_node;
+	struct bdisp_request *request = &ctx->bdisp_dev->dbg.copy_request;
+	struct bdisp_node **node = ctx->node;
+	int i;
+
+	/* Request copy */
+	request->src = ctx->src;
+	request->dst = ctx->dst;
+	request->hflip = ctx->hflip;
+	request->vflip = ctx->vflip;
+	request->nb_req++;
+
+	/* Nodes copy */
+	for (i = 0; i < MAX_NB_NODE; i++) {
+		/* Allocate memory if not done yet */
+		if (!copy_node[i]) {
+			copy_node[i] = devm_kzalloc(ctx->bdisp_dev->dev,
+						    sizeof(*copy_node),
+						    GFP_KERNEL);
+			if (!copy_node[i])
+				return;
+		}
+		copy_node[i] = node[i];
+	}
+}
+
 /**
  * bdisp_hw_update
  * @ctx:        device context
@@ -765,6 +802,9 @@ int bdisp_hw_update(struct bdisp_ctx *ctx)
 		return ret;
 	}
 
+	/* Save a copy of the request */
+	bdisp_hw_save_request(ctx);
+
 	/* Configure interrupt to 'Last Node Reached for AQ1' */
 	writel(BLT_AQ1_CTL_CFG, bdisp->regs + BLT_AQ1_CTL);
 	writel(BLT_ITS_AQ1_LNA, bdisp->regs + BLT_ITM0);

drivers/media/platform/sti/bdisp/bdisp-v4l2.c

@@ -336,6 +336,8 @@ static void bdisp_device_run(void *priv)
 		goto out;
 	}
 
+	bdisp_dbg_perf_begin(bdisp);
+
 	err = bdisp_hw_reset(bdisp);
 	if (err) {
 		dev_err(bdisp->dev, "could not get HW ready\n");
@@ -1075,6 +1077,8 @@ static irqreturn_t bdisp_irq_thread(int irq, void *priv)
 
 	spin_lock(&bdisp->slock);
 
+	bdisp_dbg_perf_end(bdisp);
+
 	cancel_delayed_work(&bdisp->timeout_work);
 
 	if (!test_and_clear_bit(ST_M2M_RUNNING, &bdisp->state))
@@ -1247,6 +1251,8 @@ static int bdisp_remove(struct platform_device *pdev)
 
 	pm_runtime_disable(&pdev->dev);
 
+	bdisp_debugfs_remove(bdisp);
+
 	v4l2_device_unregister(&bdisp->v4l2_dev);
 
 	if (!IS_ERR(bdisp->clock))
@@ -1328,12 +1334,19 @@ static int bdisp_probe(struct platform_device *pdev)
 		goto err_clk;
 	}
 
+	/* Debug */
+	ret = bdisp_debugfs_create(bdisp);
+	if (ret) {
+		dev_err(dev, "failed to create debugfs\n");
+		goto err_v4l2;
+	}
+
 	/* Power management */
 	pm_runtime_enable(dev);
 	ret = pm_runtime_get_sync(dev);
 	if (ret < 0) {
 		dev_err(dev, "failed to set PM\n");
-		goto err_v4l2;
+		goto err_dbg;
 	}
 
 	/* Continuous memory allocator */
@@ -1370,6 +1383,8 @@ static int bdisp_probe(struct platform_device *pdev)
 	vb2_dma_contig_cleanup_ctx(bdisp->alloc_ctx);
 err_pm:
 	pm_runtime_put(dev);
+err_dbg:
+	bdisp_debugfs_remove(bdisp);
 err_v4l2:
 	v4l2_device_unregister(&bdisp->v4l2_dev);
 err_clk:

drivers/media/platform/sti/bdisp/bdisp.h

@@ -140,6 +140,29 @@ struct bdisp_m2m_device {
 	int                     refcnt;
 };
 
+/**
+ * struct bdisp_dbg - debug info
+ *
+ * @debugfs_entry: debugfs
+ * @copy_node:     array of last used nodes
+ * @copy_request:  last bdisp request
+ * @hw_start:      start time of last HW request
+ * @last_duration: last HW processing duration in microsecs
+ * @min_duration:  min HW processing duration in microsecs
+ * @max_duration:  max HW processing duration in microsecs
+ * @tot_duration:  total HW processing duration in microsecs
+ */
+struct bdisp_dbg {
+	struct dentry           *debugfs_entry;
+	struct bdisp_node       *copy_node[MAX_NB_NODE];
+	struct bdisp_request    copy_request;
+	ktime_t                 hw_start;
+	s64                     last_duration;
+	s64                     min_duration;
+	s64                     max_duration;
+	s64                     tot_duration;
+};
+
 /**
  * struct bdisp_dev - abstraction for bdisp entity
  *
@@ -158,6 +181,7 @@ struct bdisp_m2m_device {
  * @irq_queue:  interrupt handler waitqueue
  * @work_queue: workqueue to handle timeouts
  * @timeout_work: IRQ timeout structure
+ * @dbg:        debug info
  */
 struct bdisp_dev {
 	struct v4l2_device      v4l2_dev;
@@ -175,6 +199,7 @@ struct bdisp_dev {
 	wait_queue_head_t       irq_queue;
 	struct workqueue_struct *work_queue;
 	struct delayed_work     timeout_work;
+	struct bdisp_dbg        dbg;
 };
 
 void bdisp_hw_free_nodes(struct bdisp_ctx *ctx);
@@ -184,3 +209,8 @@ int bdisp_hw_alloc_filters(struct device *dev);
 int bdisp_hw_reset(struct bdisp_dev *bdisp);
 int bdisp_hw_get_and_clear_irq(struct bdisp_dev *bdisp);
 int bdisp_hw_update(struct bdisp_ctx *ctx);
+
+void bdisp_debugfs_remove(struct bdisp_dev *bdisp);
+int bdisp_debugfs_create(struct bdisp_dev *bdisp);
+void bdisp_dbg_perf_begin(struct bdisp_dev *bdisp);
+void bdisp_dbg_perf_end(struct bdisp_dev *bdisp);