In the images generated by Gowin IDE, the signals for dynamic BSRAM
block selection (BLKSEL[2:0]) are not always connected directly to the
ports - some chips add LUT2, LUT3 or LUT4 to turn these signals into
Clock Enable. Apparently there are chips with an error in the operation
of these ports.
Here we make such a decoder instead of using ports directly.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
It seems that the internal registers on the BSRAM output pins in
READ_MODE=1'b1 (pipeline) mode do not function properly because in the
images generated by Gowin IDE an external register is added to each pin,
and the BSRAM itself switches to READ_MODE=1'b0 (bypass) mode .
This is observed on Tangnano9k and Tangnano20k boards.
Here we repeat this fix.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
Add description of BSRAM harness
In some cases, Gowin IDE adds a number of LUTs and DFFs to the BSRAM. Here we are trying to add similar elements.
More details with pictures: https://github.com/YosysHQ/apicula/blob/master/doc/bsram-fix.md
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
If the CLKIN input of the PLL is connected to a special pin, then it
makes sense to try to place the PLL so that it uses a direct implicit
non-switched connection to this pin.
The transfer of information about pins for various purposes has been
implemented (clock input signal, feedback, etc), but so far only CLKIN
is used.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
For the following primitives:
- PADD9
- PADD18
- MULT9X9
- MULT18X18
- MULT36X36
- MULTALU18X18
- MULTALU36X18
- MULTADDALU18X18
- ALU54D
packing and processing of fixed wires between macro and between DSP
blocks is implemented.
Clusters of DSP and macro blocks are processed using custom placement of
cluster elements.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
The OCE signal in the SP(X)9B primitive is intended to control the
built-in output register. The documentation states that this port is
invalid when READ_MODE=0 is used. However, it has been experimentally
established that you cannot simply apply VCC or GND to it and forget it
- the discrepancy between the signal on this port and the signal on the
CE port leads to both skipping data reading and unnecessary reading
after CE has switched to 0.
Here we force these ports to be connected to the network, except in the
case where the user controls the OCE signal using non-constant signals.
Also:
* All PIPs for clock spines are made inaccessible to the common router
- in general, using these routes for signals that have not been
processed by a special globals router is fraught with effects that
are difficult to detect.
* The INV primitive has been added purely to speed up development -
this primitive is not generated by Yosys, but is almost always
present in vendor output files.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
The following primitives are implemented for the GW1NZ-1 chip:
* pROM - read only memory - (bitwidth: 1, 2, 4, 8, 16, 32).
* pROMX9 - read only memory - (bitwidth: 9, 18, 36).
* SDPB - semidual port - (bitwidth: 1, 2, 4, 8, 16, 32).
* SDPX9B - semidual port - (bitwidth: 9, 18, 36).
* DPB - dual port - (bitwidth: 16).
* DPX9B - dual port - (bitwidth: 18).
* SP - single port - (bitwidth: 1, 2, 4, 8, 16, 32).
* SPX9 - single port - (bitwidth: 9, 18, 36).
Also:
- The creation of databases for GW1NS-2 has been removed - this was not
planned to be supported in Himbaechel from the very beginning and
even examples were not created in apicula for this chip due to the
lack of boards with it on sale.
- It is temporarily prohibited to connect DFFs and LUTs into clusters
because for some reason this prevents the creation of images on lower
chips (placer cannot find the placement), although without these
clusters the images are quite working. Requires further research.
- Added creation of ALU with mode 0 - addition. Such an element is not
generated by Yosys, but it is a favorite vendor element and its
support here greatly simplifies the compilation of vendor netlists.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
Information about what function (main or auxiliary) the cell performs in
these primitives is transmitted through the tile's extra data. And this
also allows us to remove the calculation of the coordinates of the
auxiliary cell on the go.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
