Hi Alex, On 3 June 2018 at 04:13, Alexander Graf <ag...@suse.de> wrote: > > > On 25.05.18 04:42, Simon Glass wrote: >> Hi Alex, >> >> On 24 May 2018 at 06:24, Alexander Graf <ag...@suse.de> wrote: >>> >>> >>> On 16.05.18 17:42, Simon Glass wrote: >>>> At present this code casts addresses to pointers so cannot be used with >>>> sandbox. Update it to use mapmem instead. >>>> >>>> Signed-off-by: Simon Glass <s...@chromium.org> >>> >>> I really dislike the whole fact that you have to call map_sysmem() at >>> all. I don't quite understand the whole point of it either - it just >>> seems to clutter the code and make it harder to follow. >> >> The purpose is to map U-Boot addresses (e.g. 0x1234) to actual >> user-space addresses in sandbox (gd->arch.ram_buf + 0x1234). >> >> Otherwise we cannot write tests which use particular addresses, and >> people have to worry about the host memory layout when using sandbox. > > Not if we write a smart enough linker script. I can try to see when I > get around to give you an example. But basically all we need to do is > reserve a section for guest ram at a constant virtual address.
Yes, but ideally that would be 0, or something small. > >>> Can't we just simply make sandbox behave like any other target instead? >> >> Actually that's the goal of the sandbox support. Memory is modelled as >> a contiguous chunk starting at 0x0, regardless of what the OS actually >> gives U-Boot in terms of addresses. > > Most platforms don't have RAM start at 0x0 (and making sure nobody > assumes it does start at 0 is a good thing). The only bit we need to > make sure is that it always starts at *the same* address on every > invocation. But if that address is 256MB, things should still be fine. Yes but putting a 10000000 base address on everything is a bit of a pain. Regards, Simon _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
