+ add custom interactive script to insert a buffer on user_clk output
and have a large buffer on core_clk
~ change pdn config to match top level
~ change sdc
~ change openlane configuration
~ reimplement based on updated views of the macros
~ change interactive script to call label_macro_pins
~ extract all spef and sdf corners using timing-scripts repo
!important same work arounds as before
- reimplement using a sparecell
- reimplement using newest open_pdks
!important using openlane pre odb with some local patches which
most if not all are merged in the current head of openlane however
still takes effort to update the interactive script to be latest
openlane compatible
!important override abstract lef generated by openlane. openlane
generates lef and mag that contain def BLOCKAGE layers that cause
congestions during top level routing
~ update the following views:
def
mag
verilog
spef(all corners)
+ add the ability to override the interactive script filename
+ add the ability to run openlane regression using regression.config
file
~ change GRT ADJUSTMENT values
~ change pointers to some files for workarounds
!important the interactive script still needs updates
!important this was done using old openlane v0.22 and its matching
pdk
!important known workarounds:
- a custom techlef is used where large metal spacing rules are the
only ones present to avoid violations by the router
- some odd behaviour happening when a macro has a lef view
with a non zero origin. so the power routing cell is (temporarily)
modified to have a zero origin and its placement has been shifted
which doesn't match the power routing mag.
- the old openlane doesn't generate multi spef corners. they
are generated using timing-scripts repo
view of constant_block which was recently merged into the repository.
The constant_block instance positions and connections were modified
slightly to avoid routing over obstruction areas.
fork of caravel (layout .mag file not copied into this commit).
The layouts of both chip_io and chip_io_alt are believed to be
complete, but need verification (with LVS).
includes RTL change inside the padframe definition to remove one
previously unnoticed hard-wired connection between VDDIO and a
3.3V domain digital input pin.
- rtl updated
~ add one column to the right to pass placement congestion
~ density adjusted (probably has no effect)
+ manually add isosubstrate layer in mag and gds from older iterations
!important still need to run dynamic simulations
!important depends on some updates to openlane
!important need to be able to recreate using newer openlane versions
the left hand side of caravan from gpio_defaults_block_14 to
gpio_defaults_block_25. Otherwise, the script that generates the
custom user configuration won't be able to change the defaults
for GPIO 25.
- high level changes:
* add larger buffers on output ports
* add buffers on input ports
* adjust sdc file increasing output load and setting a high transition
- detailed changes:
* add interactive script for openlane where the order of events is a bit shuffled
- to add obstruction before pdn
- to manually insert buffers on some ports
- to manually remove buffers inserted by synthesis on for example serial_clock_out
* change openlane config adding extra row and columns to increase the space and fit the
added buffers
* change config to enable buffering
* increase density for better placement?
* change the cell exclude list. some excluded cells didn't make sense
* ef decap cells break dynamic sims?
* add custom pdn script for to duplicate the old pdn
- misc changes:
* fix openlane makefile to properly detect interactive script
!important still need to run dynamic simulations
!important depends on some updates to openlane
update gpio_control_block config for new openlane versions:
- disable `SYNTH_BUFFERING` and `SYNTH_SIZING` to limit the design size
and fit the floorplan
- change `SYNTH_STRATEGY` to `AREA 0` to minimize design cells
- disable `PL_RESIZER_TIMING_OPTIMIZATIONS` and
enable `GLB_RESIZER_TIMING_OPTIMIZATIONS`
- remove `FP_IO_*` and replace them with `FP_DEF_TEMPLATE` for io placement
- set `DECAP_CELL` to not use ef decaps.. i think that was for simulations?
- enable some turned off `QUIT_*` variables
- replace deprecated variables such as `GLB_RT_*`
- customize `pdn.tcl` to force pdn straps to follow the old pattern
- replace `$script_dir` with `$::env(DESIGN_DIR)`
!IMPORTANT - still need to run dynamic simulations
tweak blackbox lvs scripts for very fast extract; update spi/lvs/*.spice.
The .spice (once propagated to caravel-lite AND caravel-lite embed in mpw_precheck docker)
will pass the consistency check.
Co-authored-by: Risto Bell <rb@efabless.com>
mo-hosni
kareem
Marwan Abbas
Mohamed Shalan
Tim Edwards
marwaneltoukhy
Mohamed Hosni
sto6