On Wed, Sep 30, 2015 at 3:42 PM, Max Filippov <jcmvb...@gmail.com> wrote: > On Thu, Oct 1, 2015 at 1:23 AM, Peter Crosthwaite > <crosthwaitepe...@gmail.com> wrote: >> On Wed, Sep 30, 2015 at 3:07 PM, Max Filippov <jcmvb...@gmail.com> wrote: >>> On Thu, Oct 1, 2015 at 12:02 AM, Peter Crosthwaite >>> <crosthwaitepe...@gmail.com> wrote: >>>> Which makes MMU vs noMMU a board level property, not a CPU property. >>>> It should appear in QEMU as such. >>> >>> Ok, one last try: can this property be queried from the selected CPU >>> and passed to SoC initialization code? >> >> No, what I am trying to say is go the other way round. The property is >> on the SoC, and it is used to select the CPU type. > > This is not what happens in reality. In reality the MMU type is the > CPU property. > A set of CPU properties comes from the outside along with the CPU name, and > that's the only possible set of properties for this name. > XTFPGA bitstream build scripts lay out its address space based on MMU > type of the selected CPU. > > So let's make XTFPGA an SoC with a property that selects its address space > layout. The machine (lx60/lx200/ml605/kc705) is configured with a CPU,
So lx60/lx200 sound like isolated FPGA chips (Virtex 4 lx60?) while ml605/kc705 are commonly available fully-featured FPGA dev boards. Is lx60 short for a particular board featuring this part or is it more abstract? > it > queries MMU type from it and instantiates XTFPGA SoC with proper address > space. That seems to be closest to what happens in reality. > What is your intended user command lines? E.g. how do I boot with ml605 no-mmu and then with mmu. Regards, Peter > -- > Thanks. > -- Max
