clocksource/drivers/mips-gic-timer: Refine rating computation

It is a good clocksource which usually go as fast as CPU core and have a low access latency, so raise the base of rating from Good to desired when we know that it has a stable frequency. Increase frequency addend dividend to 10000000 (10MHz) to reasonably accommodate multi GHz level clock, also cap rating within current level. Signed-off-by: Jiaxun Yang <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Daniel Lezcano <[email protected]>
mj22226 · Jul 12, 2024 · cc9b2c5 · cc9b2c5
1 parent db19d3a
commit cc9b2c5
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/drivers/clocksource/mips-gic-timer.c b/drivers/clocksource/mips-gic-timer.c
@@ -197,7 +197,11 @@ static int __init __gic_clocksource_init(void)
 	gic_clocksource.mask = CLOCKSOURCE_MASK(count_width);
 
 	/* Calculate a somewhat reasonable rating value. */
-	gic_clocksource.rating = 200 + gic_frequency / 10000000;
+	if (mips_cm_revision() >= CM_REV_CM3 || !IS_ENABLED(CONFIG_CPU_FREQ))
+		gic_clocksource.rating = 300; /* Good when frequecy is stable */
+	else
+		gic_clocksource.rating = 200;
+	gic_clocksource.rating += clamp(gic_frequency / 10000000, 0, 99);
 
 	ret = clocksource_register_hz(&gic_clocksource, gic_frequency);
 	if (ret < 0)