On 01/15/2017 04:44 PM, Andreas Färber wrote: > Am 23.12.2016 um 10:42 schrieb Heinrich Schuchardt: >> it really makes a difference if we write >> >> memory@0 { >> device_type = "memory"; >> linux,usable-memory = <0x0 0x1000000 0x0 0x7f000000>; >> }; >> >> or >> >> memory@0 { >> device_type = "memory"; >> reg = <0x0 0x1000000 0x0 0x7f000000>; >> }; >> >> The second version leads to failure of the Odroid C2. >> >> When I looked at /sys/firmware/fdt I saw this difference: >> >> --- fails >> +++ works >> >> memory@0 { >> - device_type = "memory"; >> reg = <0x0 0x0 0x0 0x78000000>; >> + device_type = "memory"; >> + linux,usable-memory = <0x0 0x1000000 0x0 0x7f000000>; >> }; >> >> I found the following sentence in the NXP forum: >> In case you want to overwrite the memory usage passed from u-boot, you >> can use "linux,usable-memory". >> https://community.nxp.com/thread/382284 > > The Odroid-C2 is in mainline U-Boot. Please submit a patch to U-Boot > instead of forcing the creation of unnecessary new .dts files onto > everyone due to hardcoded linux,usable-memory properties. In fact, it > already reserves 0x1000000, so it seems you are merely using an older > U-Boot. > > http://git.denx.de/?p=u-boot.git;a=blob;f=arch/arm/mach-meson/board.c;h=f159cbf849f75ab046e6f3a025bbc97c0bcfd59d;hb=HEAD#l39 > > I would bet that the upper limit is unrelated here. > > Regards, > Andreas > Hi Andreas, I really disagree about relying on any work or properties added by any bootloader here, Amlogic SoCs has a lot of u-boot version in the field, and the Odroid-C2 is part of this. Even if Odroid-c2 is in mainline U-Boot or not, the mainline Linux kernel should work using any U-boot version even with the one provided by Amlogic on their openlinux distribution channel. Neil -- 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