APUS bus access

[<fh...@at...>]

Hi,

I posted a message on the Linux SCSI mailing list about the problems I am
having with the 53c770 driver.   The current maitainor
Gerard Rondier replied.

Is there any reason the APUS kernel would not allow 32 bit access to the
Amiga Hardware or memory especially on the PowerUP board?
  

> The reason I ask, is that when the driver puts the  "pc" value into the
> DSP register it is bf2fe50, but when the value  is read back out it is
> "bf2".

Weird ... 16 bit reversed in a DWORD + 16 bit lost.
Or the BUS access reads 16 bits instead of 32 bits.

> To my logic it seems that either the  correct value may not have
> got into the register due to an alignment problem, or the read back value
> cannot be guaranteed to be
> correct due to properties of the particular register.

If you write 32 bits at a given IO (MMIO) address and read back the same
location and width, you should get all the 4 bytes, possibly in a
different order if the glue that does IO is not endian-consistent.


Fred