Boards such as the Xilinx VC707, STLV7325, etc. offer support for
dual-rank memory, which results in a 512-bit wide native LiteDRAM
port. These additional "8x wide" (or "octo") variants support that
width directly, without the need for additional data width conversion
that whould have to be implemented on the LiteX side of the SoC.
Suggested-by: Icenowy Zheng <uwu@icenowy.me>
Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
CPUs with a dedicated memory port (MemBus) are typically connected
directly to the LiteDRAM port. Some models (e.g., Rocket) come in
(otherwise equivalent) variants specifically pre-generated to fit
the various "standard" LiteDRAM port widths (so far, 64, 128, or
256 bits).
This patch introduces a warning when the CPU variant's dedicated
MemBus doesn't exactly match the width of LiteDRAM, requiring
explicit conversion.
The goal is to inform the user and provide them with an opportunity
to pick a more suitable CPU variant (of matching MemBus width), if
available.
Allow adding multiple SPIFlash with different names to the SoC. The BIOS will
only use "spiflash" for now but the other SPI Flash core will be accessible.
Fix#1514.
Precisions made to the LICENSE were not legal modifications to the License, just some moral precisions since things don't seemed clear for everyone.
(Won't elaborate on this, but were some reasons add these precisions).
These precisions are just willing to protect the work of the community/developers and allow the project to continue being developed with a
BSD 2-Clause License: ie share almost everything that is developed, without even thinking about potential business opportunities.
Since moral aspects seems to be modifying the license, these are just integrated in the README.md and are still a condition to:
- Expect the community to be welcoming.
- Expect free or even paid support (moral/integrity is more important than $$$ for us).
- Expect the contributions to be accepted/integrated.
So if you don't want to respect the moral precisions, up to you to use the project, but please
be coherent with yourself and don't use our time/energy; just improve/implement things by yourself :)
Move to the latest Ubuntu LTS for updated tooling. This requires us to
drop the zlibc package which no longer exists, and doesn't appear to be
required. Also update to the master branch of the GHDL action as this
contains 22.04 support.
Signed-off-by: Joel Stanley <joel@jms.id.au>
For designs willing to put the reset address of the CPU in a region not directly handled by LiteX,
self.cpu.disable_reset_address_check() can be used in the SoC to disable CPU reset address check.
Right now, when multiple masters want to access the bus,
access is granted to one of them, and is not revoked until
selected master has finished all of its transactions (cyc goes low).
This state causes master starvation if access is granted to high
bandwidth master, like cpu in busy loop.
This commit makes it so access to bus is revoked when pending transaction
is finished (ack and cyc are high) or when selected master is idle.
Signed-off-by: Maciej Dudek <mdudek@antmicro.com>
This commit fixes a bug where, retry after timeout would send another
request, but wouldn't discard a response that arrived after the timeout.
Retries worked, but only for dropped packets. If a response arrived, but
`socker.recvfrom` timed out, response would still be put in receive
queue. Later after sending another request, client would try to read
from the socket and would find a response. But this response would be
for the old request.
This way request/response pairs would get misaligned and stop working
properly.
This commit adds read numbering (writes do not have responses).
Numbering is achieved by utilizing the fact that responses to Etherbone
reads are actually writes to an address specified in a request.
This way, we don't need to extend Etherbone protocol, in fact we use it
as it is intended.
This numbering is then used to discard responses that don't match
current request.
I also cleaned setting of the timeout, as it was being set in multiple
places, sometimes to values so small that retry was bound to happen.
Signed-off-by: Michal Sieron <msieron@antmicro.com>