On Sat, Mar 23, 2019 at 10:01:23PM +0800, qiaozhou wrote: > From: Qiao Zhou <qiaozhou@xxxxxxxxxxxx> > > Add binding documentation for ASR8751C AXI/APB bus that are used > to interface with peripherals. AXI/APB bus follow standard AXI/APB > protocols. > > Signed-off-by: qiaozhou <qiaozhou@xxxxxxxxxxxx> > --- > Documentation/devicetree/bindings/bus/asr,bus.txt | 42 +++++++++++++++++++++++ > 1 file changed, 42 insertions(+) > create mode 100644 Documentation/devicetree/bindings/bus/asr,bus.txt > > diff --git a/Documentation/devicetree/bindings/bus/asr,bus.txt b/Documentation/devicetree/bindings/bus/asr,bus.txt > new file mode 100644 > index 0000000..cbb1b6e > --- /dev/null > +++ b/Documentation/devicetree/bindings/bus/asr,bus.txt > @@ -0,0 +1,42 @@ > +* ASR AXI/APB Simple Bus > + > +This file documents core properties in ASR AXI and APB bus. > + > +The ASR8751C SoC has APB and AXI buses for cores to access its > +controllers, suchas i2c, sdh, rtc, clock, power management registers s/suchas/such as/ > +etc. Most ASR SoCs share the common architecture for buses. > +Generally APB and AXI bus have a source clock and power control, and > +clock rate can be changed and power can be shutdown in low power mode. Then where are the clocks? > + > +Required properties for AXI bus: > +- compatible: should be "asr,axi-bus", "simple-bus". > +- #address-cells: could be 1, or 2 > +- #size-cells: could be 1, or 2 > +- reg: iomem address of AXI bus registers > +- ranges: register ranges > + > +Example: > + axi@d4200000 { /* AXI */ > + compatible = "asr,axi-bus", "simple-bus"; > + #address-cells = <1>; > + #size-cells = <1>; > + reg = <0 0xd4200000 0 0x00200000>; > + ranges = <0 0 0 0xffffffff>; > + > + }; > + > +Required properties for APB bus: > +- compatible: should be "asr,apb-bus", "simple-bus". > +- #address-cells: could be 1, or 2 > +- #size-cells: could be 1, or 2 > +- reg: iomem address of APB bus registers > +- ranges: register ranges > + > +Example: > + apb@d4000000 { /* APB */ > + compatible = "asr,apb-bus", "simple-bus"; > + #address-cells = <1>; > + #size-cells = <1>; > + reg = <0 0xd4000000 0 0x00200000>; > + ranges = <0 0 0 0xffffffff>; > + }; > -- > 2.7.4 >