The commit 6900c have added an additional register stage into the fifo read
data path, but the control signals (ready/valid/underflow) were not realigned
to the data. This can cause data lose or duplicated samples in some case.
Realign the control signals to the data.
The first attempt (f3daf0) faild miserably. When the data_req signal
from the device had more than 1 cycle of deassert state, because of the
added latency of the data stream, the device got 'zeros' too.
In this fix, the DMA will hold the valid data on the bus, between two
consecutive data request. The bus is reseted just after all the data
were sent out.
Reset the fifo_rd_data if the DMA does not have an active transfer.
Becasue all the DAC device cores are transfering the data from the FIFO
interface to the data interface without any validation signal, DMA needs to put
the data bus into a known state, to prevent the device core to send the
last known data again and again.
All the hdl (verilog and vhdl) source files were updated. If a file did not
have any license, it was added into it. Files, which were generated by
a tool (like Matlab) or were took over from other source (like opencores.org),
were unchanged.
New license looks as follows:
Copyright 2014 - 2017 (c) Analog Devices, Inc. All rights reserved.
Each core or library found in this collection may have its own licensing terms.
The user should keep this in in mind while exploring these cores.
Redistribution and use in source and binary forms,
with or without modification of this file, are permitted under the terms of either
(at the option of the user):
1. The GNU General Public License version 2 as published by the
Free Software Foundation, which can be found in the top level directory, or at:
https://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html
OR
2. An ADI specific BSD license as noted in the top level directory, or on-line at:
https://github.com/analogdevicesinc/hdl/blob/dev/LICENSE
Refactor the fifo_inf modules to always correctly generate the underflow and
overflow status signals. Before it was possible that in some cases they
were not generated when they should have been.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
There were a few place in the core where it assumed a 64-bit wide bus. Make this
configurable using parameters. The patch also adds support for having different
DMA bus widths on the source and destination side.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Istvan Csomortani
Lars-Peter Clausen
Adrian Costina