On Tuesday 04 November 2014 14:36:45 HC Yen wrote: > > > + > > > +#include <dt-bindings/interrupt-controller/irq.h> > > > +#include <dt-bindings/interrupt-controller/arm-gic.h> > > > +#include "skeleton64.dtsi" > > > > Cortex a7 is 32 bits, right? So why do you use skeleton64.dtsi? > > Cortex-A7 is 32-bit, but that doesn't mean it can only have 32-bit > physical address. With LPAE enabled, we can have physical address more > than 32 bits. > > The main difference between "skeleton64.dtsi" and "skeleton.dtsi" is > "#address-cells" property set to 2. Although there are few sources > using "skeleton64.dtsi", some of them write "#address-cells = <2>" > directly in order to have 64-bit address space. ARM's TC2 reference > platform (vexpress-v2p-ca15_a7.dts) is an example. > > Some of MediaTek ARMv7 SoCs support address space larger than 4GB. It > will be convenient to share the sources if we all use 64-bit device > tree. Right, in general, I'd use #address-cells=<2> for Cortex-A7/A15/A17. Arnd -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
