in the range [0x0000 - 0x0100) some registers are owned by the CPU and some by board devices. CPU registers will be accessed by helper_fullrd & helper_fullwr whereas device registers e.g. USB, will be handled by USB provided it's possible to add rd/wr handlers for specific io addresses.
On Wed, Jul 6, 2016 at 12:43 PM, Peter Maydell <peter.mayd...@linaro.org> wrote: > On 6 July 2016 at 10:36, Michael Rolnik <mrol...@gmail.com> wrote: > > Peter, > > > > I think I will do the following > > 1. helper fullwr will modify CPU owned registers by itself and call > cpu_outb > > for non owned registers > > 2. I will add helper fullrd that will behave like fullwr. > > 3. any board/model will have to install a device in the io space for > > registers not owned by the CPU. > > > > it will make sample_io.c device obsolete and make (future) devices more > > independent. > > > > what do you think? > > Could you please point me to an example how to create a device in the io > > space? > > What does the device in the IO space need to do? > > thanks > -- PMM > -- Best Regards, Michael Rolnik
