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Re: How to access PCI memory(HELP)....


> >
> > PCI_IOSPACE_BASE only maps PCI device IO registers, not memory
> > mappings. I don't believe we actually use any of these mappings, which
> > appear at 0x0C000000/0xAC000000 physical/logical addresses.
> >
> > We also use the master address windows. Window one is set up to map
> > the 4372 control registers at 0x1C000000 in PCI space to
> > 0x1C000000/0xBC000000 in the CPU. Window 2 maps 0x80000000 in PCI
> > space to 0x80000000 physical which the MMU remaps to 0xC0000000
> > logical. However, the 4372 also occupies the first 256Mb of this.
> >

Nick,

I still have question on why 4372 will occupies the first 256Mb of the PCI
space, where we initialize this setting, can we decrease the space size.
Currently I change to following configuration,

<1>. HAL_PCI_PHYSICAL_MEMORY_BASE to 0x4000_0000
<2>. HAL_PCI_ALLOC_BASE_MEMORY to 0x8000_0000
<3>. NUMB_PG to 8

I can observe signal from PCI bus by using Logic Analyzer, of course, I
wonder if this will conflict with 4372 address space. But anyway right now I
can see signals on PCI pci bus, I haven't fully verify this. I doubt it will
have some conflict with serial port debugging if 4372 also mapps to this
space.

I will go ahead to check my PCI FPGA logic, in the meantime, I hope you can
give me some idea and suggestion on the 4372 mapping stuff. Thanks a lot!

Best Regards,
-Ling



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