tools/power/turbostat: Add support for Xe sysfs knobs

Xe graphics driver uses different graphics sysfs knobs including
   /sys/class/drm/card0/device/tile0/gt0/gtidle/idle_residency_ms
   /sys/class/drm/card0/device/tile0/gt0/freq0/cur_freq
   /sys/class/drm/card0/device/tile0/gt0/freq0/act_freq
   /sys/class/drm/card0/device/tile0/gt1/gtidle/idle_residency_ms
   /sys/class/drm/card0/device/tile0/gt1/freq0/cur_freq
   /sys/class/drm/card0/device/tile0/gt1/freq0/act_freq

Plus that,
   /sys/class/drm/card0/device/tile0/gt<n>/gtidle/name
returns either gt<n>-rc or gt<n>-mc. rc is for GFX and mc is SA Media.

Enhance turbostat to prefer the Xe sysfs knobs when they are available.
Export gt<n>-rc via BIC_GFX_rc6/BIC_GFXMHz/BIC_GFXACTMHz.
Export gt<n>-mc via BIC_SMA_mc6/BIC_SMAMHz/BIC_SMAACTMHz.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

tools/power/x86/turbostat/turbostat.c

@@ -5380,6 +5380,57 @@ static void probe_intel_uncore_frequency(void)
 
 static void probe_graphics(void)
 {
+	/* Xe graphics sysfs knobs */
+	if (!access("/sys/class/drm/card0/device/tile0/gt0/gtidle/idle_residency_ms", R_OK)) {
+		FILE *fp;
+		char buf[8];
+		bool gt0_is_gt;
+		int idx;
+
+		fp = fopen("/sys/class/drm/card0/device/tile0/gt0/gtidle/name", "r");
+		if (!fp)
+			goto next;
+
+		if (!fread(buf, sizeof(char), 7, fp)) {
+			fclose(fp);
+			goto next;
+		}
+		fclose(fp);
+
+		if (!strncmp(buf, "gt0-rc", strlen("gt0-rc")))
+			gt0_is_gt = true;
+		else if (!strncmp(buf, "gt0-mc", strlen("gt0-mc")))
+			gt0_is_gt = false;
+		else
+			goto next;
+
+		idx = gt0_is_gt ? GFX_rc6 : SAM_mc6;
+		gfx_info[idx].path = "/sys/class/drm/card0/device/tile0/gt0/gtidle/idle_residency_ms";
+
+		idx = gt0_is_gt ? GFX_MHz : SAM_MHz;
+		if (!access("/sys/class/drm/card0/device/tile0/gt0/freq0/cur_freq", R_OK))
+			gfx_info[idx].path = "/sys/class/drm/card0/device/tile0/gt0/freq0/cur_freq";
+
+		idx = gt0_is_gt ? GFX_ACTMHz : SAM_ACTMHz;
+		if (!access("/sys/class/drm/card0/device/tile0/gt0/freq0/act_freq", R_OK))
+			gfx_info[idx].path = "/sys/class/drm/card0/device/tile0/gt0/freq0/act_freq";
+
+		idx = gt0_is_gt ? SAM_mc6 : GFX_rc6;
+		if (!access("/sys/class/drm/card0/device/tile0/gt1/gtidle/idle_residency_ms", R_OK))
+			gfx_info[idx].path = "/sys/class/drm/card0/device/tile0/gt1/gtidle/idle_residency_ms";
+
+		idx = gt0_is_gt ? SAM_MHz : GFX_MHz;
+		if (!access("/sys/class/drm/card0/device/tile0/gt1/freq0/cur_freq", R_OK))
+			gfx_info[idx].path = "/sys/class/drm/card0/device/tile0/gt1/freq0/cur_freq";
+
+		idx = gt0_is_gt ? SAM_ACTMHz : GFX_ACTMHz;
+		if (!access("/sys/class/drm/card0/device/tile0/gt1/freq0/act_freq", R_OK))
+			gfx_info[idx].path = "/sys/class/drm/card0/device/tile0/gt1/freq0/act_freq";
+
+		goto end;
+	}
+
+next:
 	/* New i915 graphics sysfs knobs */
 	if (!access("/sys/class/drm/card0/gt/gt0/rc6_residency_ms", R_OK)) {
 		gfx_info[GFX_rc6].path = "/sys/class/drm/card0/gt/gt0/rc6_residency_ms";