[Intel-gfx] [PATCH i-g-t 7/7] lib/igt_kms: Use kernel command line mode if specified

Brian Starkey brian.starkey at arm.com
Tue Apr 25 16:45:13 UTC 2017


If "video=" is specified on the kernel command-line, use it to override
the default mode in kmstest_get_connector_default_mode.

If a mode override was provided on the command-line, it was probably for
good reason so we should honor it.

Signed-off-by: Brian Starkey <brian.starkey at arm.com>
---
 lib/igt_kms.c |  135 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 135 insertions(+)

diff --git a/lib/igt_kms.c b/lib/igt_kms.c
index 474aa005b9fa..97f80a46354d 100644
--- a/lib/igt_kms.c
+++ b/lib/igt_kms.c
@@ -766,6 +766,131 @@ void kmstest_force_edid(int drm_fd, drmModeConnector *connector,
 	igt_assert(ret != -1);
 }
 
+/*
+ * Extract xres, yres, refresh and interlaced from a string of the form:
+ *   <xres>x<yres>[M][R][-<bpp>][@<refresh>][i][m][eDd]
+ * xres and yres must be specified, refresh is optional and will be set to
+ * -1 if not present. interlaced defaults to false.
+ */
+static int parse_cmdline_mode(char *video_str, unsigned int *xres,
+			      unsigned int *yres,
+			      int *refresh, bool *interlaced)
+{
+	int match, len = strlen(video_str);
+	char *token = strtok(video_str, "@");
+
+	if (!token)
+		return -1;
+
+	*interlaced = false;
+	*refresh = -1;
+
+	match = sscanf(token, "%dx%d", xres, yres);
+	if (match != 2)
+		return -1;
+
+	if (strlen(token) < len - 1) {
+		token += strlen(token) + 1;
+
+		match = sscanf(token, "%d", refresh);
+		if (match != 1 || (*refresh < 0))
+			return -1;
+
+		if (strchr(token, 'i'))
+			*interlaced = true;
+	}
+
+	return 0;
+}
+
+static const drmModeModeInfo *
+connector_match_cmdline_mode(const drmModeConnector *connector,
+			     unsigned int xres, unsigned int yres, int refresh,
+			     bool interlaced)
+{
+	const drmModeModeInfo *mode = NULL;
+	int i;
+
+	for (i = 0; i < connector->count_modes; i++) {
+		mode = &connector->modes[i];
+		if (mode->hdisplay == xres &&
+		    mode->vdisplay == yres &&
+		    (refresh < 0 || refresh == mode->vrefresh) &&
+		    interlaced == !!(mode->flags & DRM_MODE_FLAG_INTERLACE))
+			return mode;
+	}
+
+	return NULL;
+}
+
+static const drmModeModeInfo *
+kmstest_get_cmdline_mode(int drm_fd, drmModeConnector *connector)
+{
+	char c, *str = NULL, *cursor, *conn_name = NULL;
+	const drmModeModeInfo *mode = NULL;
+	unsigned int size = 0;
+	FILE *fp = NULL;
+
+	fp = fopen("/proc/cmdline", "r");
+	if (!fp)
+		return NULL;
+
+	/* lseek/fseek+ftell/stat don't work on /proc/cmdline */
+	while (fread(&c, 1, 1, fp))
+		size++;
+	rewind(fp);
+
+	str = calloc(1, size + 1);
+	if (!str)
+		goto done;
+
+	if (fread(str, 1, size, fp) != size)
+		goto done;
+
+	if (!asprintf(&conn_name, "%s-%d:",
+		      kmstest_connector_type_str(connector->connector_type),
+		      connector->connector_type_id))
+		goto done;
+
+	cursor = str;
+	while ((cursor = strstr(cursor, "video="))) {
+		unsigned int xres, yres;
+		bool interlaced;
+		int refresh;
+
+		cursor += strlen("video=");
+		cursor = strtok(cursor, " \n");
+		if (!cursor)
+			break;
+
+		/* Strip the name if it matches ours */
+		if (!strncmp(cursor, conn_name, strlen(conn_name)))
+			cursor += strlen(conn_name);
+
+		/*
+		 * Consider this "video=" specification only if it has no
+		 * name. If the name matched, we would have already stripped it
+		 * above
+		 */
+		if (!strstr(cursor, ":") &&
+		    !parse_cmdline_mode(cursor, &xres, &yres, &refresh, &interlaced)) {
+			mode = connector_match_cmdline_mode(connector, xres,
+							    yres, refresh,
+							    interlaced);
+			if (mode)
+				break;
+		}
+
+		cursor += strlen(cursor) + 1;
+	}
+
+done:
+	free(conn_name);
+	free(str);
+	fclose(fp);
+	return mode;
+}
+
 /**
  * kmstest_get_connector_default_mode:
  * @drm_fd: DRM fd
@@ -773,6 +898,8 @@ void kmstest_force_edid(int drm_fd, drmModeConnector *connector,
  * @mode: libdrm mode
  *
  * Retrieves the default mode for @connector and stores it in @mode.
+ * If video= is specified (optionally for this specific connector) on the
+ * kernel command line, then it is used as the default.
  *
  * Returns: true on success, false on failure
  */
@@ -780,6 +907,7 @@ bool kmstest_get_connector_default_mode(int drm_fd, drmModeConnector *connector,
 					drmModeModeInfo *mode)
 {
 	int i;
+	const drmModeModeInfo *cmdline_mode;
 
 	if (!connector->count_modes) {
 		igt_warn("no modes for connector %d\n",
@@ -787,6 +915,13 @@ bool kmstest_get_connector_default_mode(int drm_fd, drmModeConnector *connector,
 		return false;
 	}
 
+	cmdline_mode = kmstest_get_cmdline_mode(drm_fd, connector);
+	if (cmdline_mode) {
+		*mode = *cmdline_mode;
+		igt_debug("Using cmdline mode\n");
+		return true;
+	}
+
 	for (i = 0; i < connector->count_modes; i++) {
 		if (i == 0 ||
 		    connector->modes[i].type & DRM_MODE_TYPE_PREFERRED) {
-- 
1.7.9.5



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