Documentation: devicetree: Update Exynos MCT bindings description

This patch updates description of device tree bindings for Exynos MCT
(multicore timers). Namely:
 - added note about simplified specification of local timer interrupts,
   when using single per-processor interrupt for all local timers,
 - changed first example that was incorrectly suggesting that global
   timer interrupts are optional,
 - simplified example interrupt map,
 - added example showing simplified local timer interrupt specification.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

diff --git a/Documentation/devicetree/bindings/timer/samsung,exynos4210-mct.txt b/Documentation/devicetree/bindings/timer/samsung,exynos4210-mct.txt
index b5a86d2..167d5da 100644 (file)
--- a/Documentation/devicetree/bindings/timer/samsung,exynos4210-mct.txt
+++ b/Documentation/devicetree/bindings/timer/samsung,exynos4210-mct.txt
@@ -31,38 +31,58 @@ Required properties:
        7: ..
        i: Local Timer Interrupt n
 
-Example 1: In this example, the system uses only the first global timer
-          interrupt generated by MCT and the remaining three global timer
-          interrupts are unused. Two local timer interrupts have been
-          specified.
+  For MCT block that uses a per-processor interrupt for local timers, such
+  as ones compatible with "samsung,exynos4412-mct", only one local timer
+  interrupt might be specified, meaning that all local timers use the same
+  per processor interrupt.
+
+Example 1: In this example, the IP contains two local timers, using separate
+          interrupts, so two local timer interrupts have been specified,
+          in addition to four global timer interrupts.
 
        mct@10050000 {
                compatible = "samsung,exynos4210-mct";
                reg = <0x10050000 0x800>;
-               interrupts = <0 57 0>, <0 0 0>, <0 0 0>, <0 0 0>,
+               interrupts = <0 57 0>, <0 69 0>, <0 70 0>, <0 71 0>,
                             <0 42 0>, <0 48 0>;
        };
 
-Example 2: In this example, the MCT global and local timer interrupts are
-          connected to two separate interrupt controllers. Hence, an
-          interrupt-map is created to map the interrupts to the respective
-          interrupt controllers.
+Example 2: In this example, the timer interrupts are connected to two separate
+          interrupt controllers. Hence, an interrupt-map is created to map
+          the interrupts to the respective interrupt controllers.
 
        mct@101C0000 {
                compatible = "samsung,exynos4210-mct";
                reg = <0x101C0000 0x800>;
-               interrupt-controller;
-               #interrups-cells = <2>;
                interrupt-parent = <&mct_map>;
-               interrupts = <0 0>, <1 0>, <2 0>, <3 0>,
-                            <4 0>, <5 0>;
+               interrupts = <0>, <1>, <2>, <3>, <4>, <5>;
 
                mct_map: mct-map {
-                       #interrupt-cells = <2>;
+                       #interrupt-cells = <1>;
                        #address-cells = <0>;
                        #size-cells = <0>;
-                       interrupt-map = <0x0 0 &combiner 23 3>,
-                                       <0x4 0 &gic 0 120 0>,
-                                       <0x5 0 &gic 0 121 0>;
+                       interrupt-map = <0 &gic 0 57 0>,
+                                       <1 &gic 0 69 0>,
+                                       <2 &combiner 12 6>,
+                                       <3 &combiner 12 7>,
+                                       <4 &gic 0 42 0>,
+                                       <5 &gic 0 48 0>;
                };
        };
+
+Example 3: In this example, the IP contains four local timers, but using
+          a per-processor interrupt to handle them. Either all the local
+          timer interrupts can be specified, with the same interrupt specifier
+          value or just the first one.
+
+       mct@10050000 {
+               compatible = "samsung,exynos4412-mct";
+               reg = <0x10050000 0x800>;
+
+               /* Both ways are possible in this case. Either: */
+               interrupts = <0 57 0>, <0 69 0>, <0 70 0>, <0 71 0>,
+                            <0 42 0>;
+               /* or: */
+               interrupts = <0 57 0>, <0 69 0>, <0 70 0>, <0 71 0>,
+                            <0 42 0>, <0 42 0>, <0 42 0>, <0 42 0>;
+       };