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author | whitequark <whitequark@whitequark.org> | 2020-01-01 08:27:47 +0000 |
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committer | whitequark <whitequark@whitequark.org> | 2020-02-06 16:52:51 +0000 |
commit | 081d9318bcf1ee13549ddcb0983cba5f00b4272c (patch) | |
tree | 9cc64505a7e60cfec38ef80b93d3b6721a50919d /tests/arch/ice40 | |
parent | 3f4460a1869ccfd6225379d18ade195f165841a4 (diff) | |
download | yosys-081d9318bcf1ee13549ddcb0983cba5f00b4272c.tar.gz yosys-081d9318bcf1ee13549ddcb0983cba5f00b4272c.tar.bz2 yosys-081d9318bcf1ee13549ddcb0983cba5f00b4272c.zip |
ecp5: add support for both 1364.1 and LSE RAM/ROM attributes.
This commit tries to carefully follow the documented behavior of LSE
and Synplify. It will use `syn_ramstyle` attribute if there are any
write ports, and `syn_romstyle` attribute otherwise.
* LSE supports both `syn_ramstyle` and `syn_romstyle`.
* Synplify only supports `syn_ramstyle`, with same values as LSE.
* Synplify also supports `syn_rw_conflict_logic`, which is not
documented as supported for LSE.
Limitations of the Yosys implementation:
* LSE/Synplify support `syn_ramstyle="block_ram,no_rw_check"`
syntax to turn off insertion of transparency logic. There is
currently no way to support multiple valued attributes in
memory_bram. It is also not clear if that is a good idea, since
it can cause sim/synth mismatches.
* LSE/Synplify/1364.1 support block ROM inference from full case
statements. Yosys does not currently perform this transformation.
* LSE/Synplify propagate `syn_ramstyle`/`syn_romstyle` attributes
from the module to the inner memories. There is currently no way
to do this in Yosys (attrmvcp only works on cells and wires).
Diffstat (limited to 'tests/arch/ice40')
-rw-r--r-- | tests/arch/ice40/memories.ys | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/tests/arch/ice40/memories.ys b/tests/arch/ice40/memories.ys index 43bcf2452..86a60b258 100644 --- a/tests/arch/ice40/memories.ys +++ b/tests/arch/ice40/memories.ys @@ -1,3 +1,4 @@ +# ================================ RAM ================================ # RAM bits <= 4K; Data width <= 16; Address width <= 11: -> SB_RAM40_4K design -reset; read_verilog ../common/blockram.v @@ -48,6 +49,13 @@ select -assert-count 1 t:SB_RAM40_4K design -reset; read_verilog ../common/blockram.v chparam -set ADDRESS_WIDTH 2 -set DATA_WIDTH 8 sync_ram_sdp +setattr -set syn_ramstyle "registers" m:memory +synth_ice40 -top sync_ram_sdp; cd sync_ram_sdp +select -assert-count 0 t:SB_RAM40_4K # requested FFRAM explicitly +select -assert-min 1 t:SB_DFFE + +design -reset; read_verilog ../common/blockram.v +chparam -set ADDRESS_WIDTH 2 -set DATA_WIDTH 8 sync_ram_sdp setattr -set logic_block 1 m:memory synth_ice40 -top sync_ram_sdp; cd sync_ram_sdp select -assert-count 0 t:SB_RAM40_4K # requested FFRAM explicitly @@ -67,6 +75,7 @@ synth_ice40 -top sync_ram_sdp; cd sync_ram_sdp select -assert-count 0 t:SB_RAM40_4K # requested BROM but this is a RAM select -assert-min 1 t:SB_DFFE +# ================================ ROM ================================ # ROM bits <= 4K; Data width <= 16; Address width <= 11: -> SB_RAM40_4K design -reset; read_verilog ../common/blockrom.v @@ -112,6 +121,13 @@ select -assert-count 1 t:SB_RAM40_4K design -reset; read_verilog ../common/blockrom.v chparam -set ADDRESS_WIDTH 2 -set DATA_WIDTH 8 sync_rom +setattr -set syn_romstyle "logic" m:memory +synth_ice40 -top sync_rom; cd sync_rom +select -assert-count 0 t:SB_RAM40_4K # requested LUTROM explicitly +select -assert-min 1 t:SB_LUT4 + +design -reset; read_verilog ../common/blockrom.v +chparam -set ADDRESS_WIDTH 2 -set DATA_WIDTH 8 sync_rom setattr -set logic_block 1 m:memory synth_ice40 -top sync_rom; cd sync_rom select -assert-count 0 t:SB_RAM40_4K # requested LUTROM explicitly |