overlay: Add graph for GPU power consumption

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 14 insertions, 8 deletions

diff --git a/overlay/gpu-freq.c b/overlay/gpu-freq.c
index 545ba781..23af1d48 100644
--- a/overlay/gpu-freq.c
+++ b/overlay/gpu-freq.c
@@ -15,37 +15,40 @@ int gpu_freq_init(struct gpu_freq *gf)
 
 	fd = open("/sys/kernel/debug/dri/0/i915_cur_delayinfo", 0);
 	if (fd < 0)
-		return errno;
+		return gf->error = errno;
 
 	len = read(fd, buf, sizeof(buf)-1);
 	close(fd);
 	if (len < 0)
-		return EIO;
+		goto err;
 
 	buf[len] = '\0';
 
 	s = strstr(buf, "(RPN)");
 	if (s == NULL)
-		return EIO;
+		goto err;
 	sscanf(s, "(RPN) frequency: %dMHz", &gf->rpn);
 
 	s = strstr(s, "(RP1)");
 	if (s == NULL)
-		return EIO;
+		goto err;
 	sscanf(s, "(RP1) frequency: %dMHz", &gf->rp1);
 
 	s = strstr(s, "(RP0)");
 	if (s == NULL)
-		return EIO;
+		goto err;
 	sscanf(s, "(RP0) frequency: %dMHz", &gf->rp0);
 
 	s = strstr(s, "Max");
 	if (s == NULL)
-		return EIO;
+		goto err;
 	sscanf(s, "Max overclocked frequency: %dMHz", &gf->max);
 	gf->min = gf->rpn;
 
 	return 0;
+
+err:
+	return gf->error = EIO;
 }
 
 int gpu_freq_update(struct gpu_freq *gf)
@@ -53,14 +56,17 @@ int gpu_freq_update(struct gpu_freq *gf)
 	char buf[4096], *s;
 	int fd, len = -1;
 
+	if (gf->error)
+		return gf->error;
+
 	fd = open("/sys/kernel/debug/dri/0/i915_cur_delayinfo", 0);
 	if (fd < 0)
-		return errno;
+		return gf->error = errno;
 
 	len = read(fd, buf, sizeof(buf)-1);
 	close(fd);
 	if (len < 0)
-		return EIO;
+		return gf->error = EIO;
 
 	buf[len] = '\0';