ARM: integrator: deactivate timer0 on the Integrator/CP

linusw · olofj · commit 29114fd7db2f · 2013-10-13T14:07:21.000-07:00
This fixes a long-standing Integrator/CP regression from commit 870e292 "ARM: integrator-cp: convert use CLKSRC_OF for timer init" When this code was introduced, the both aliases pointing the system to use timer1 as primary (clocksource) and timer2 as secondary (clockevent) was ignored, and the system would simply use the first two timers found as clocksource and clockevent. However this made the system timeline accelerate by a factor x25, as it turns out that the way the clocking actually works (totally undocumented and found after some trial-and-error) is that timer0 runs @ 25MHz and timer1 and timer2 runs @ 1MHz. Presumably this divider setting is a boot-on default and configurable albeit the way to configure it is not documented. So as a quick fix to the problem, let's mark timer0 as disabled, so the code will chose timer1 and timer2 as it used to. This also deletes the two aliases for the primary and secondary timer as they have been superceded by the auto-selection Cc: stable@vger.kernel.org Cc: Rob Herring <rob.herring@calxeda.com> Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Olof Johansson <olof@lixom.net>
diff --git a/arch/arm/boot/dts/integratorcp.dts b/arch/arm/boot/dts/integratorcp.dts
@@ -9,11 +9,6 @@
 	model = "ARM Integrator/CP";
 	compatible = "arm,integrator-cp";
 
-	aliases {
-		arm,timer-primary = &timer2;
-		arm,timer-secondary = &timer1;
-	};
-
 	chosen {
 		bootargs = "root=/dev/ram0 console=ttyAMA0,38400n8 earlyprintk";
 	};
@@ -24,14 +19,18 @@
 	};
 
 	timer0: timer@13000000 {
+		/* TIMER0 runs @ 25MHz */
 		compatible = "arm,integrator-cp-timer";
+		status = "disabled";
 	};
 
 	timer1: timer@13000100 {
+		/* TIMER1 runs @ 1MHz */
 		compatible = "arm,integrator-cp-timer";
 	};
 
 	timer2: timer@13000200 {
+		/* TIMER2 runs @ 1MHz */
 		compatible = "arm,integrator-cp-timer";
 	};
 
