Hi!

I'm trying the access an I2C bus through a FPGA that is
attached to the XBUS.

I have mapped the XBUS using the following code:

  ...
  map_valid = uvm_map_reserve(kernel_map, NBPG, 0, &fpga_address);
  if(map_valid == FALSE)
    {
      panic("fpga: no mapping\n");
    }
  pmap_enter(pmap_kernel(), (vm_offset_t)fpga_address,
    trunc_page(DC21285_XBUS_XCS1), VM_PROT_WRITE, TRUE, VM_PROT_WRITE);
  ...

This results in that I must flush the data cache when I have
set a bit in the register that controls the I2C bus. But when I
call "cpu_cache_flushD" the system halts.

I'm I doing something wrong here? Can I set the pages to be non-cachable
or something similar?

-- 
Johan Rydberg			johan.rydberg@netinsight.net
Net Insight AB, Sweden		direct: +46-8-685 04 17
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