ARM: dts: revise kona clock binding document

The next patch defines a binding for a new Broadcom SoC that uses
Kona style CCUs for its clocks.  Update the generic Kona clock
binding document so it's more natural to accomodate the definitions
of additional SoC families.

Specifically:
    - Define the compatible string values generically, referring
      to specific per-model values later in the document.
    - Put the device tree example immediately after the required
      properties listing, before the tables of SoC-specific values.
    - Clearly identify the start of the section defining specific
      values related to the BCM281XX family
    - Add a list of the specific BCM281XX family compatible strings.
    - Reword the description of the table slightly.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
This commit is contained in:
Alex Elder 2014-04-21 16:26:24 -05:00 committed by Mike Turquette
parent 0bdab78ba6
commit 5bcb59260f
1 changed files with 47 additions and 40 deletions

View File

@ -10,12 +10,12 @@ This binding uses the common clock binding:
Required properties:
- compatible
Shall have one of the following values:
- "brcm,bcm11351-root-ccu"
- "brcm,bcm11351-aon-ccu"
- "brcm,bcm11351-hub-ccu"
- "brcm,bcm11351-master-ccu"
- "brcm,bcm11351-slave-ccu"
Shall have a value of the form "brcm,<model>-<which>-ccu",
where <model> is a Broadcom SoC model number and <which> is
the name of a defined CCU. For example:
"brcm,bcm11351-root-ccu"
The compatible strings used for each supported SoC family
are defined below.
- reg
Shall define the base and range of the address space
containing clock control registers
@ -26,12 +26,48 @@ Required properties:
Shall be an ordered list of strings defining the names of
the clocks provided by the CCU.
Device tree example:
BCM281XX family SoCs use Kona CCUs. The following table defines
the set of CCUs and clock specifiers for BCM281XX clocks. When
a clock consumer references a clocks, its symbolic specifier
(rather than its numeric index value) should be used. These
specifiers are defined in "include/dt-bindings/clock/bcm281xx.h".
slave_ccu: slave_ccu {
compatible = "brcm,bcm11351-slave-ccu";
reg = <0x3e011000 0x0f00>;
#clock-cells = <1>;
clock-output-names = "uartb",
"uartb2",
"uartb3",
"uartb4";
};
ref_crystal_clk: ref_crystal {
#clock-cells = <0>;
compatible = "fixed-clock";
clock-frequency = <26000000>;
};
uart@3e002000 {
compatible = "brcm,bcm11351-dw-apb-uart", "snps,dw-apb-uart";
status = "disabled";
reg = <0x3e002000 0x1000>;
clocks = <&slave_ccu BCM281XX_SLAVE_CCU_UARTB3>;
interrupts = <GIC_SPI 65 IRQ_TYPE_LEVEL_HIGH>;
reg-shift = <2>;
reg-io-width = <4>;
};
BCM281XX family
---------------
CCU compatible string values for SoCs in the BCM281XX family are:
"brcm,bcm11351-root-ccu"
"brcm,bcm11351-aon-ccu"
"brcm,bcm11351-hub-ccu"
"brcm,bcm11351-master-ccu"
"brcm,bcm11351-slave-ccu"
The following table defines the set of CCUs and clock specifiers for
BCM281XX family clocks. When a clock consumer references a clocks,
its symbolic specifier (rather than its numeric index value) should
be used. These specifiers are defined in:
"include/dt-bindings/clock/bcm281xx.h"
CCU Clock Type Index Specifier
--- ----- ---- ----- ---------
@ -62,32 +98,3 @@ specifiers are defined in "include/dt-bindings/clock/bcm281xx.h".
slave bsc2 peri 7 BCM281XX_SLAVE_CCU_BSC2
slave bsc3 peri 8 BCM281XX_SLAVE_CCU_BSC3
slave pwm peri 9 BCM281XX_SLAVE_CCU_PWM
Device tree example:
slave_ccu: slave_ccu {
compatible = "brcm,bcm11351-slave-ccu";
reg = <0x3e011000 0x0f00>;
#clock-cells = <1>;
clock-output-names = "uartb",
"uartb2",
"uartb3",
"uartb4";
};
ref_crystal_clk: ref_crystal {
#clock-cells = <0>;
compatible = "fixed-clock";
clock-frequency = <26000000>;
};
uart@3e002000 {
compatible = "brcm,bcm11351-dw-apb-uart", "snps,dw-apb-uart";
status = "disabled";
reg = <0x3e002000 0x1000>;
clocks = <&slave_ccu BCM281XX_SLAVE_CCU_UARTB3>;
interrupts = <GIC_SPI 65 IRQ_TYPE_LEVEL_HIGH>;
reg-shift = <2>;
reg-io-width = <4>;
};