On 08/21/2014 08:33 AM, Peter Maydell wrote: > On 21 August 2014 04:37, Peter Crosthwaite <peter.crosthwa...@xilinx.com> > wrote: >> On Thu, Aug 21, 2014 at 11:40 AM, Alistair Francis <alistai...@gmail.com> >> wrote: >>> On Thu, Aug 21, 2014 at 11:36 AM, Alistair Francis <alistai...@gmail.com> >>> wrote: >>>> This allows the board to set the reset address, which is required >>>> for some boards (the Netduino Plus 2 for example) > >> The change is armv7m specific right? You should mention that in the >> commit message. >> >> This also obsoletes my attempt at correcting armv7m elf loading which >> was trying to solve this issue a different way. > > I think the ELF loading thing is a separate issue -- if we're loading > an ELF file we should honour its entry point address instead of > trying to load from the vector table. (The question of what we > do about SP is an interesting one...)
In my experience with A-profile, software is expected to either know enough about the platform to set the SP to something sane itself or make the SYS_HEAPINFO semihosting call, which despite the name returns both stack and heap information. http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0471j/pge1358787054284.html An example of the former option is the semihosting bootwrapper, which designates an address in RAM as the top of the stack. https://github.com/virtualopensystems/boot-wrapper/blob/master/model.lds.S#L57 For the latter option, my recollection is that ELF binaries built with Newlib and ARM's C library will make the semihosting call. Christopher -- Employee of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by the Linux Foundation.
