drm/sti: add debugfs fps_show/fps_get mechanism for planes

Display fps on demand for each used plane:
cat /sys/kernel/debug/dri/0/fps_get
Display fps in live in the console for each used plane:
echo 255 > /sys/kernel/debug/dri/0/fps_show

Signed-off-by: Vincent Abriou <vincent.abriou@st.com>
Reviewed-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>

drivers/gpu/drm/sti/sti_cursor.c

@@ -306,6 +306,8 @@ static void sti_cursor_atomic_update(struct drm_plane *drm_plane,
 	writel(cursor->clut_paddr, cursor->regs + CUR_CML);
 	writel(CUR_CTL_CLUT_UPDATE, cursor->regs + CUR_CTL);
 
+	sti_plane_update_fps(plane, true, false);
+
 	plane->status = STI_PLANE_UPDATED;
 }
 

drivers/gpu/drm/sti/sti_drv.c

@@ -20,6 +20,7 @@
 
 #include "sti_crtc.h"
 #include "sti_drv.h"
+#include "sti_plane.h"
 
 #define DRIVER_NAME	"sti"
 #define DRIVER_DESC	"STMicroelectronics SoC DRM"
@@ -30,6 +31,130 @@
 #define STI_MAX_FB_HEIGHT	4096
 #define STI_MAX_FB_WIDTH	4096
 
+static int sti_drm_fps_get(void *data, u64 *val)
+{
+	struct drm_device *drm_dev = data;
+	struct drm_plane *p;
+	unsigned int i = 0;
+
+	*val = 0;
+	list_for_each_entry(p, &drm_dev->mode_config.plane_list, head) {
+		struct sti_plane *plane = to_sti_plane(p);
+
+		*val |= plane->fps_info.output << i;
+		i++;
+	}
+
+	return 0;
+}
+
+static int sti_drm_fps_set(void *data, u64 val)
+{
+	struct drm_device *drm_dev = data;
+	struct drm_plane *p;
+	unsigned int i = 0;
+
+	list_for_each_entry(p, &drm_dev->mode_config.plane_list, head) {
+		struct sti_plane *plane = to_sti_plane(p);
+
+		plane->fps_info.output = (val >> i) & 1;
+		i++;
+	}
+
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(sti_drm_fps_fops,
+			sti_drm_fps_get, sti_drm_fps_set, "%llu\n");
+
+static int sti_drm_fps_dbg_show(struct seq_file *s, void *data)
+{
+	struct drm_info_node *node = s->private;
+	struct drm_device *dev = node->minor->dev;
+	struct drm_plane *p;
+	int ret;
+
+	ret = mutex_lock_interruptible(&dev->struct_mutex);
+	if (ret)
+		return ret;
+
+	list_for_each_entry(p, &dev->mode_config.plane_list, head) {
+		struct sti_plane *plane = to_sti_plane(p);
+
+		seq_printf(s, "%s%s\n",
+			   plane->fps_info.fps_str,
+			   plane->fps_info.fips_str);
+	}
+
+	mutex_unlock(&dev->struct_mutex);
+	return 0;
+}
+
+static struct drm_info_list sti_drm_dbg_list[] = {
+	{"fps_get", sti_drm_fps_dbg_show, 0},
+};
+
+static int sti_drm_debugfs_create(struct dentry *root,
+				  struct drm_minor *minor,
+				  const char *name,
+				  const struct file_operations *fops)
+{
+	struct drm_device *dev = minor->dev;
+	struct drm_info_node *node;
+	struct dentry *ent;
+
+	ent = debugfs_create_file(name, S_IRUGO | S_IWUSR, root, dev, fops);
+	if (IS_ERR(ent))
+		return PTR_ERR(ent);
+
+	node = kmalloc(sizeof(*node), GFP_KERNEL);
+	if (!node) {
+		debugfs_remove(ent);
+		return -ENOMEM;
+	}
+
+	node->minor = minor;
+	node->dent = ent;
+	node->info_ent = (void *)fops;
+
+	mutex_lock(&minor->debugfs_lock);
+	list_add(&node->list, &minor->debugfs_list);
+	mutex_unlock(&minor->debugfs_lock);
+
+	return 0;
+}
+
+static int sti_drm_dbg_init(struct drm_minor *minor)
+{
+	int ret;
+
+	ret = drm_debugfs_create_files(sti_drm_dbg_list,
+				       ARRAY_SIZE(sti_drm_dbg_list),
+				       minor->debugfs_root, minor);
+	if (ret)
+		goto err;
+
+	ret = sti_drm_debugfs_create(minor->debugfs_root, minor, "fps_show",
+				     &sti_drm_fps_fops);
+	if (ret)
+		goto err;
+
+	DRM_INFO("%s: debugfs installed\n", DRIVER_NAME);
+	return 0;
+err:
+	DRM_ERROR("%s: cannot install debugfs\n", DRIVER_NAME);
+	return ret;
+}
+
+void sti_drm_dbg_cleanup(struct drm_minor *minor)
+{
+	drm_debugfs_remove_files(sti_drm_dbg_list,
+				 ARRAY_SIZE(sti_drm_dbg_list), minor);
+
+	drm_debugfs_remove_files((struct drm_info_list *)&sti_drm_fps_fops,
+				 1, minor);
+}
+
 static void sti_atomic_schedule(struct sti_private *private,
 				struct drm_atomic_state *state)
 {
@@ -215,6 +340,9 @@ static struct drm_driver sti_driver = {
 	.gem_prime_vunmap = drm_gem_cma_prime_vunmap,
 	.gem_prime_mmap = drm_gem_cma_prime_mmap,
 
+	.debugfs_init = sti_drm_dbg_init,
+	.debugfs_cleanup = sti_drm_dbg_cleanup,
+
 	.name = DRIVER_NAME,
 	.desc = DRIVER_DESC,
 	.date = DRIVER_DATE,

drivers/gpu/drm/sti/sti_gdp.c

@@ -850,6 +850,8 @@ static void sti_gdp_atomic_update(struct drm_plane *drm_plane,
 	}
 
 end:
+	sti_plane_update_fps(plane, true, false);
+
 	plane->status = STI_PLANE_UPDATED;
 }
 

drivers/gpu/drm/sti/sti_hqvdp.c

@@ -326,8 +326,6 @@ struct sti_hqvdp_cmd {
  * @reset:             reset control
  * @vtg_nb:            notifier to handle VTG Vsync
  * @btm_field_pending: is there any bottom field (interlaced frame) to display
- * @curr_field_count:  number of field updates
- * @last_field_count:  number of field updates since last fps measure
  * @hqvdp_cmd:         buffer of commands
  * @hqvdp_cmd_paddr:   physical address of hqvdp_cmd
  * @vtg:               vtg for main data path
@@ -343,8 +341,6 @@ struct sti_hqvdp {
 	struct reset_control *reset;
 	struct notifier_block vtg_nb;
 	bool btm_field_pending;
-	unsigned int curr_field_count;
-	unsigned int last_field_count;
 	void *hqvdp_cmd;
 	dma_addr_t hqvdp_cmd_paddr;
 	struct sti_vtg *vtg;
@@ -836,11 +832,12 @@ int sti_hqvdp_vtg_cb(struct notifier_block *nb, unsigned long evt, void *data)
 		writel(hqvdp->hqvdp_cmd_paddr + btm_cmd_offset,
 				hqvdp->regs + HQVDP_MBX_NEXT_CMD);
 
-		hqvdp->curr_field_count++;
 		hqvdp->btm_field_pending = false;
 
 		dev_dbg(hqvdp->dev, "%s Posted command:0x%x\n",
 				__func__, hqvdp->hqvdp_cmd_paddr);
+
+		sti_plane_update_fps(&hqvdp->plane, false, true);
 	}
 
 	return 0;
@@ -1204,8 +1201,6 @@ static void sti_hqvdp_atomic_update(struct drm_plane *drm_plane,
 	writel(hqvdp->hqvdp_cmd_paddr + cmd_offset,
 	       hqvdp->regs + HQVDP_MBX_NEXT_CMD);
 
-	hqvdp->curr_field_count++;
-
 	/* Interlaced : get ready to display the bottom field at next Vsync */
 	if (fb->flags & DRM_MODE_FB_INTERLACED)
 		hqvdp->btm_field_pending = true;
@@ -1213,6 +1208,8 @@ static void sti_hqvdp_atomic_update(struct drm_plane *drm_plane,
 	dev_dbg(hqvdp->dev, "%s Posted command:0x%x\n",
 		__func__, hqvdp->hqvdp_cmd_paddr + cmd_offset);
 
+	sti_plane_update_fps(plane, true, true);
+
 	plane->status = STI_PLANE_UPDATED;
 }
 

drivers/gpu/drm/sti/sti_plane.c

@@ -43,6 +43,69 @@ const char *sti_plane_to_str(struct sti_plane *plane)
 	}
 }
 
+#define STI_FPS_INTERVAL_MS     3000
+
+static int sti_plane_timespec_ms_diff(struct timespec lhs, struct timespec rhs)
+{
+	struct timespec tmp_ts = timespec_sub(lhs, rhs);
+	u64 tmp_ns = (u64)timespec_to_ns(&tmp_ts);
+
+	do_div(tmp_ns, NSEC_PER_MSEC);
+
+	return (u32)tmp_ns;
+}
+
+void sti_plane_update_fps(struct sti_plane *plane,
+			  bool new_frame,
+			  bool new_field)
+{
+	struct timespec now;
+	struct sti_fps_info *fps;
+	int fpks, fipks, ms_since_last, num_frames, num_fields;
+
+	getrawmonotonic(&now);
+
+	/* Compute number of frame updates */
+	fps = &plane->fps_info;
+
+	if (new_field)
+		fps->curr_field_counter++;
+
+	/* do not perform fps calcul if new_frame is false */
+	if (!new_frame)
+		return;
+
+	fps->curr_frame_counter++;
+	ms_since_last = sti_plane_timespec_ms_diff(now, fps->last_timestamp);
+	num_frames = fps->curr_frame_counter - fps->last_frame_counter;
+
+	if (num_frames <= 0  || ms_since_last < STI_FPS_INTERVAL_MS)
+		return;
+
+	fps->last_timestamp = now;
+	fps->last_frame_counter = fps->curr_frame_counter;
+	fpks = (num_frames * 1000000) / ms_since_last;
+	snprintf(plane->fps_info.fps_str, FPS_LENGTH, "%-6s @ %d.%.3d fps",
+		 sti_plane_to_str(plane), fpks / 1000, fpks % 1000);
+
+	if (fps->curr_field_counter) {
+		/* Compute number of field updates */
+		num_fields = fps->curr_field_counter - fps->last_field_counter;
+		fps->last_field_counter = fps->curr_field_counter;
+		fipks = (num_fields * 1000000) / ms_since_last;
+		snprintf(plane->fps_info.fips_str,
+			 FPS_LENGTH, " - %d.%.3d field/sec",
+			 fipks / 1000, fipks % 1000);
+	} else {
+		plane->fps_info.fips_str[0] = '\0';
+	}
+
+	if (fps->output)
+		DRM_INFO("%s%s\n",
+			 plane->fps_info.fps_str,
+			 plane->fps_info.fips_str);
+}
+
 static void sti_plane_destroy(struct drm_plane *drm_plane)
 {
 	DRM_DEBUG_DRIVER("\n");

drivers/gpu/drm/sti/sti_plane.h

@@ -50,6 +50,18 @@ enum sti_plane_status {
 	STI_PLANE_DISABLED,
 };
 
+#define FPS_LENGTH 64
+struct sti_fps_info {
+	bool output;
+	unsigned int curr_frame_counter;
+	unsigned int last_frame_counter;
+	unsigned int curr_field_counter;
+	unsigned int last_field_counter;
+	struct timespec last_timestamp;
+	char fps_str[FPS_LENGTH];
+	char fips_str[FPS_LENGTH];
+};
+
 /**
  * STI plane structure
  *
@@ -57,15 +69,20 @@ enum sti_plane_status {
  * @desc:               plane type & id
  * @status:             to know the status of the plane
  * @zorder:             plane z-order
+ * @fps_info:           frame per second info
  */
 struct sti_plane {
 	struct drm_plane drm_plane;
 	enum sti_plane_desc desc;
 	enum sti_plane_status status;
 	int zorder;
+	struct sti_fps_info fps_info;
 };
 
 const char *sti_plane_to_str(struct sti_plane *plane);
+void sti_plane_update_fps(struct sti_plane *plane,
+			  bool new_frame,
+			  bool new_field);
 void sti_plane_init_property(struct sti_plane *plane,
 			     enum drm_plane_type type);
 #endif