Document the device tree binding for Broadcom Kona architecture clock control units and clocks. Kona device nodes are represented with compatible strings having "bcm11351" in their name. Kona clocks are managed by "clock control units" (CCUs). Each CCU has a device tree node, and within that node are defined the names of the clocks provided by the CCU. The BCM281xx family of SoCs use Kona CCUs and clocks. Signed-off-by: Alex Elder <elder@xxxxxxxxxx> Reviewed-by: Matt Porter <matt.porter@xxxxxxxxxx> Reviewed-by: Tim Kryger <tim.kryger@xxxxxxxxxx> --- v2: - list all CCU compatible strings explicitly - reworded a few things, and deleted some text - CCUs and clocks are now defined at the root level - added reference to header file that defines specifiers .../devicetree/bindings/clock/bcm-kona-clock.txt | 93 ++++++++++++++++++++ 1 file changed, 93 insertions(+) create mode 100644 Documentation/devicetree/bindings/clock/bcm-kona-clock.txt diff --git a/Documentation/devicetree/bindings/clock/bcm-kona-clock.txt b/Documentation/devicetree/bindings/clock/bcm-kona-clock.txt new file mode 100644 index 0000000..56d1f49 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/bcm-kona-clock.txt @@ -0,0 +1,93 @@ +Broadcom Kona Family Clocks + +This binding is associated with Broadcom SoCs having "Kona" style +clock control units (CCUs). A CCU is a clock provider that manages +a set of clock signals. Each CCU is represented by a node in the +device tree. + +This binding uses the common clock binding: + Documentation/devicetree/bindings/clock/clock-bindings.txt + +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" +- reg + Shall define the base and range of the address space + containing clock control registers +- #clock-cells + Shall have value <1>. The permitted clock-specifier values + are defined below. +- clock-output-names + Shall be an ordered list of strings defining the names of + the clocks provided by the CCU. + + +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". + + CCU Clock Type Index Specifier + --- ----- ---- ----- --------- + root frac_1m peri 0 BCM281XX_ROOT_CCU_FRAC_1M + + aon hub_timer peri 0 BCM281XX_AON_CCU_HUB_TIMER + aon pmu_bsc peri 1 BCM281XX_AON_CCU_PMU_BSC + aon pmu_bsc_var peri 2 BCM281XX_AON_CCU_PMU_BSC_VAR + + hub tmon_1m peri 0 BCM281XX_HUB_CCU_TMON_1M + + master sdio1 peri 0 BCM281XX_MASTER_CCU_SDIO1 + master sdio2 peri 1 BCM281XX_MASTER_CCU_SDIO2 + master sdio3 peri 2 BCM281XX_MASTER_CCU_SDIO3 + master sdio4 peri 3 BCM281XX_MASTER_CCU_SDIO4 + master dmac peri 4 BCM281XX_MASTER_CCU_DMAC + master usb_ic peri 5 BCM281XX_MASTER_CCU_USB_IC + master hsic2_48m peri 6 BCM281XX_MASTER_CCU_HSIC_48M + master hsic2_12m peri 7 BCM281XX_MASTER_CCU_HSIC_12M + + slave uartb peri 0 BCM281XX_SLAVE_CCU_UARTB + slave uartb2 peri 1 BCM281XX_SLAVE_CCU_UARTB2 + slave uartb3 peri 2 BCM281XX_SLAVE_CCU_UARTB3 + slave uartb4 peri 3 BCM281XX_SLAVE_CCU_UARTB4 + slave ssp0 peri 4 BCM281XX_SLAVE_CCU_SSP0 + slave ssp2 peri 5 BCM281XX_SLAVE_CCU_SSP2 + slave bsc1 peri 6 BCM281XX_SLAVE_CCU_BSC1 + 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>; + }; -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html