overlay: Add GPU frequency

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

1 files changed, 75 insertions, 0 deletions

diff --git a/overlay/gpu-freq.c b/overlay/gpu-freq.c
new file mode 100644
index 00000000..f0285a5f
--- /dev/null
+++ b/overlay/gpu-freq.c
@@ -0,0 +1,75 @@
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <string.h>
+#include <stdio.h>
+
+#include "gpu-freq.h"
+
+int gpu_freq_init(struct gpu_freq *gf)
+{
+	char buf[4096], *s;
+	int fd, len = -1;
+
+	memset(gf, 0, sizeof(*gf));
+
+	fd = open("/sys/kernel/debug/dri/0/i915_cur_delayinfo", 0);
+	if (fd < 0)
+		return errno;
+
+	len = read(fd, buf, sizeof(buf)-1);
+	close(fd);
+	if (len < 0)
+		return EIO;
+
+	buf[len] = '\0';
+
+	s = strstr(buf, "(RPN)");
+	if (s == NULL)
+		return EIO;
+	sscanf(s, "(RPN) frequency: %dMHz", &gf->rpn);
+
+	s = strstr(s, "(RP1)");
+	if (s == NULL)
+		return EIO;
+	sscanf(s, "(RP1) frequency: %dMHz", &gf->rp1);
+
+	s = strstr(s, "(RP0)");
+	if (s == NULL)
+		return EIO;
+	sscanf(s, "(RP0) frequency: %dMHz", &gf->rp0);
+
+	s = strstr(s, "Max");
+	if (s == NULL)
+		return EIO;
+	sscanf(s, "Max overclocked frequency: %dMHz", &gf->max);
+
+	return 0;
+}
+
+int gpu_freq_update(struct gpu_freq *gf)
+{
+	char buf[4096], *s;
+	int fd, len = -1;
+
+	fd = open("/sys/kernel/debug/dri/0/i915_cur_delayinfo", 0);
+	if (fd < 0)
+		return errno;
+
+	len = read(fd, buf, sizeof(buf)-1);
+	close(fd);
+	if (len < 0)
+		return EIO;
+
+	buf[len] = '\0';
+
+	s = strstr(buf, "RPNSWREQ:");
+	if (s)
+		sscanf(s, "RPNSWREQ: %dMHz", &gf->request);
+
+	s = strstr(buf, "CAGF:");
+	if (s)
+		sscanf(s, "CAGF: %dMHz", &gf->current);
+
+	return 0;
+}