[3/4] Documentation: devicetree: Add cpu clock configuration data binding for Exynos3250

Commit Message

Chanwoo Choi June 13, 2014, 6:08 a.m. UTC

The clock block of Exynos3250 add new properties to support cpu clock provider.
To register cpu clock provider of Exynos3250, must need armclk-provider-table
which includes various dividers to change CPU clock to support Exynos3250 cpufreq.

Cc: Thomas Abraham <[e-mail]>
Cc: Tomasz Figa <[e-mail]>
Cc: Rob Herring <[e-mail]>
Cc: Pawel Moll <[e-mail]>
Cc: Mark Rutland <[e-mail]>
Cc: Ian Campbell <[e-mail]>
Cc: Kumar Gala <[e-mail]>
Cc: <[e-mail]>
Signed-off-by: Chanwoo Choi <[e-mail]>
Acked-by: Kyungmin Park <[e-mail]>
---
 .../devicetree/bindings/clock/exynos3250-clock.txt | 32 ++++++++++++++++++++++
 1 file changed, 32 insertions(+)

Patch

diff --git a/Documentation/devicetree/bindings/clock/exynos3250-clock.txt b/Documentation/devicetree/bindings/clock/exynos3250-clock.txt
index aadc9c5..189b506 100644
--- a/Documentation/devicetree/bindings/clock/exynos3250-clock.txt
+++ b/Documentation/devicetree/bindings/clock/exynos3250-clock.txt
@@ -13,6 +13,25 @@  Required Properties:
 
 - #clock-cells: should be 1.
 
+- samsung,armclk-divider-table: when the frequency of the APLL is changed
+  the divider clocks in CMU_CPU clock domain also need to be updated. These
+  divider clocks have SoC specific divider clock output requirements for a
+  specific APLL clock speeds. When APLL clock rate is changed, these divider
+  clocks are reprogrammed with pre-determined values in order to maintain the
+  SoC specific divider clock outputs. This property lists the divider values
+  for divider clocks in the CMU_CPU block for supported APLL clock speeds.
+  The format of each entry included in the arm-frequency-table should be
+  as defined below
+
+      cell #1: expected arm clock parent frequency
+      cell #2 ~ cell #7: value of clock divider in the following order
+		corem_ratio, atb_ratio, pclk_dbg_ratio, apll_ratio,
+		copy_ratio, hpm_ratio
+
+- samsung,armclk-cells: defines the number of cells in
+  samsung,armclk-divider-table property. The value of this property depends on
+  the SoC type.
+
 Each clock is assigned an identifier and client nodes can use this identifier
 to specify the clock which they consume.
 
@@ -26,6 +45,19 @@  Example 1: An example of a clock controller node is listed below.
 		compatible = "samsung,exynos3250-cmu";
 		reg = <0x10030000 0x20000>;
 		#clock-cells = <1>;
+
+		samsung,armclk-cells = <7>;
+		samsung,armclk-divider-table =
+			<1000000 1 4 7 1 7 7>,
+			<900000  1 3 7 1 7 7>,
+			<800000  1 3 7 1 7 7>,
+			<700000  1 3 7 1 7 7>,
+			<600000  1 3 7 1 7 7>,
+			<500000  1 3 7 1 7 7>,
+			<400000  1 3 7 1 7 7>,
+			<300000  1 3 5 1 7 7>,
+			<200000  1 3 3 1 7 7>,
+			<100000  1 1 1 1 7 7>;
 	};
 
 Example 2: UART controller node that consumes the clock generated by the clock