Hi All
a slight followup to my earlier question about writing an openOCD
flash driver for the Synopsys ARC CPU/peripheral
By way of a slight detour, we are attempting to perform simple
read/writes via openOCD to control the Synopsys SPI peripheral.
The registers on this are memory-mapped; we are using (via python & RPC,
but I think that is irrelevant) 'mdw' and 'mww' etc. commands to
try and read the registers on the peripheral.
We are seeing some strange results which I strongly suspect relate to
some auto-incrementing properties of the ARCs JTAG implementation.
I presume this is done in order to minimise JTAG accesses when
reading/writing memory.
I am trying to find the consequence of this in the openOCD ARC code, but
I am thinking perhaps there is a way of
specifying that certain address spaces are occupied with 'peripheral
registers' rather than physical memory, and avoiding the
unwonted extra read which I think I am seeing.
I haven't been able to find any such thing; any pointers please, or to
other ways of getting round this auto-incrementing feature?
Synopsys' Metaware debugger, using the same HW and JTAG adapter, can
read these peripheral registers seemingly
without the problem, so there must be a way...
Thanks for any pointers
Jon N
