A programmable on-chip crystal oscillator has been implemented for the
GW5A series.
A critical innovation in this series was the change in the nature of the
OSC output pin—it now belongs to the clock wires, and therefore the
routes must be made with a special global router, as there is no
possibility of using routing through general-purpose PIPs.
At the same time, we are transferring the outputs of all previous
generations of OSC to potential clock wires. At the moment, this will
not affect the way they are routed - they will still end up as segments
as before, but in the future we may optimize the mechanism.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
The ALUs in the GW5A series have undergone changes compared to previous
chips.
The most significant change is the appearance of an input MUX for
carry — it is now possible to switch between VCC, GND, and COUT of the
previous ALU, as well as generate carry in logic.
The granularity of resource allocation for ALUs has also changed — it is
now possible to use each half of a slice independently for ALUs.
Not all new features are reflected in this commit:
- since there is one CIN MUX for every six ALUs and it only works for
ALUs with index 0, the new granularity is not very useful: the head of
the chain can only be placed in the zero ALU. It is possible to gain one
LUT by allocating ALUs in odd numbers, but we will leave that for the
future.
- using CIN MUX to generate carry in logic is interesting, but we have
not yet been able to get the vendor IDE to generate such a
configuration to figure out which wires are used, so for now we are
leaving the old behavior in logic with the allocation of a specialized
head ALU.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
Prior to the 5A series, pin functions (GPIO/SSPI/JTAG/DONE/etc) were
switched using fuses. This was done during the binary image formation
stage for loading into the FPGA using the command line keys of the
gowin_pack program.
The 5A series features certain ports that connect to VCC or GND
depending on whether the pin is used as SSPI or GPIO, for example. This
mechanism exists in parallel with fuses, but it is not described
anywhere, nor is there a corresponding primitive.
To generate working images, we have no choice but to simulate this thing
at the nextpnr stage, since VCC/GND routing is required.
For now, two flags are added, responsible for the SSPI and I2C pin
functions.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
Adds automatic connection of a general-purpose pin to the global clock
network.
The old behaviour, where such networks have to be explicitly specified,
can be activated with the command line key
"--vopt disable_gp_clock_routing".
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
DLLDLY is the clock delay primitive that adjust the input clock
according to the DLLSTEP signal and outputs the delayed clock.
These primitives are associated with clock pins and are "tapped" between
the output of this IBUF and the clock networks, leaving the possibility
to connect to the original unshifted signal as well, although the latter
is not very practical because it is no longer possible to use fast
wires.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
Gowin chips have an interesting mechanism - wires that run vertically
through several rows (at least 10) in each column of the chip. In each
row a particular wire has branches to the left and right, covering on
average 4 neighboring cells in the row. For lack of a better term, I
further call such a wire a segment.
So a segment can provide a direct connection in a local rectangle. There
are no special restrictions on the sinks, so segment networks can be
used for ClockEnable, LocalSetReset, as well as for LUT and DFF inputs.
The sources are not so simple - the sources can be the upper or lower
end of the segment, which in theory can lead to unfortunate consequences
if the signal is applied from both ends.
The matter is complicated by the fact that there are default
connections, i.e. in the absence of any set fuse the segment input is
still connected to something (VCC for example) and to disable the unused
end of the segment you need to set a special combination of fuses.
Taking into account which end of which segment is used is one of the
tasks of this router. In addition, segment ends can physically coincide
with PLL, DSP and BSRAM inputs, which can also lead to unexpected
effects. Some of these things are tracked when generating the base, some
in this router, some when packing in gowin_pack.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
Adds the ability to use high-speed clock lines (together with CLKDIV2
type frequency dividers operating on them) as sieve signals for the
CLKIN and CLKFB inputs of the rPLL and PLLVR primitives (these cover the
full range of supported Gowin chips).
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
* Gowin. Add I3C io buffer.
A buffer is added that can operate as a normal IOBUF in PUSH-PULL mode
or switch to open-drain IOBUF mode.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
* Gowin. Turn a variable into a set of flags
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
---------
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
* Gowin. FFs placement.
* Allow clusters to be created from FFs and LUTs;
* Immediately create pass-through LUTs from free LUTs adjacent to FF - at the same time ensure alternating use of LUT inputs;
* In case of constant networks, such pass-through LUTs are disconnected from networks altogether;
* Allow FF to be placed directly into SSRAM slides - this is useful when using synchronous reading.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
* Gowin. Fix aux name creation
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
* Gowin. Use I3 for pass-trough LUTs
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
---------
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
* Gowin. Add DHCEN primitive.
This primitive allows you to dynamically turn off and turn on the
networks of high-speed clocks.
This is done tracking the routes to the sinks and if the route passes
through a special HCLK MUX (this may be the input MUX or the output MUX,
as well as the interbank MUX), then the control signal of this MUX is
used.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
* Gowin. Change the DHCEN binding
Use the entire PIP instead of a wire - avoids normalisation and may also
be useful in the future when calculating clock stuff.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
---------
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
* Himbaechel Gowin: Add support for CLKDIV and CLKDIV2
* Himbaechel Gowin: Add support for CLKDIV and CLKDIV2
* Gowin Himbaechel: HCLK Bug fixes and corrections
DQCE and DCS primitives are added.
DQCE allows the internal logic to enable or disable the clock network in
the quadrant. When clock network is disabled, all logic drivern by this
clock is no longer toggled, thus reducing the total power consumtion of
the device.
DCS allows you to select one of four sources for two clock wires (6 and 7).
Wires 6 and 7 have not been used up to this point.
Since "hardware" primitives operate strictly in their own quadrants,
user-specified primitives are converted into one or more "hardware"
primitives as needed.
Also:
- minor edits to make the most of helper functions like connectPorts()
- when creating bases, the corresponding constants are assigned to the
VCC and GND wires, but for now huge nodes are used because, for an
unknown reason, the constants mechanism makes large examples
inoperable. So for now we remain on the nodes.
Compatible with older Apicula databases.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
As the board on the GW1N-1 chip becomes a rarity, its replacement is the
Tangnano1k board with the GW1NZ-1 chip. This chip has a unique mechanism
for turning off power to important things such as OSC, PLL, etc.
Here we introduce a primitive that allows energy saving to be controlled
dynamically.
We also bring the names of some functions to uniformity.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>
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>
Corrects the situation when it is impossible to use IOBUF with two
IOLOGIC elements at the same time - input and output.
Addresses https://github.com/YosysHQ/nextpnr/issues/1275
This is done by dividing one IOLOGIC Bel into two - input IOLOGIC and
output IOLOGIC plus checking for compatibility of the cells located
there.
At the moment, this check is simple and allows only the combination of
DDR and DDRC primitives.
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>
YRabbit
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