yosys/techlibs/xilinx/brams.txt

bram $__XILINX_RAMB36_SDP72
  abits 9
  dbits 72
  groups 2
  ports  1 1
  wrmode 0 1
  enable 0 8
  transp 2 0
  clocks 2 3
  clkpol 2 3
endbram

bram $__XILINX_RAMB36_SDP36
  abits 10
  dbits 36
  groups 2
  ports  1 1
  wrmode 0 1
  enable 0 4
  transp 2 0
  clocks 2 3
  clkpol 2 3
endbram

bram $__XILINX_RAMB36_SDP18
  abits 11
  dbits 18
  groups 2
  ports  1 1
  wrmode 0 1
  enable 0 2
  transp 2 0
  clocks 2 3
  clkpol 2 3
endbram

bram $__XILINX_RAMB36_SDP9
  abits 12
  dbits 9
  groups 2
  ports  1 1
  wrmode 0 1
  enable 0 1
  transp 2 0
  clocks 2 3
  clkpol 2 3
endbram

bram $__XILINX_RAMB36_SDP4
  abits 13
  dbits 4
  groups 2
  ports  1 1
  wrmode 0 1
  enable 0 1
  transp 2 0
  clocks 2 3
  clkpol 2 3
endbram

bram $__XILINX_RAMB36_SDP2
  abits 14
  dbits 2
  groups 2
  ports  1 1
  wrmode 0 1
  enable 0 1
  transp 2 0
  clocks 2 3
  clkpol 2 3
endbram

bram $__XILINX_RAMB36_SDP1
  abits 15
  dbits 1
  groups 2
  ports  1 1
  wrmode 0 1
  enable 0 1
  transp 2 0
  clocks 2 3
  clkpol 2 3
endbram

match $__XILINX_RAMB36_SDP72
  shuffle_enable 8
  # min efficiency 20
  # or_next_if_better
endmatch

# match $__XILINX_RAMB36_SDP36
#   shuffle_enable 4
#   min efficiency 20
#   or_next_if_better
# endmatch
#
# match $__XILINX_RAMB36_SDP18
#   shuffle_enable 2
#   min efficiency 20
#   or_next_if_better
# endmatch
#
# match $__XILINX_RAMB36_SDP9
#   min efficiency 20
#   or_next_if_better
# endmatch
#
# match $__XILINX_RAMB36_SDP4
#   min efficiency 20
#   or_next_if_better
# endmatch
#
# match $__XILINX_RAMB36_SDP2
#   min efficiency 20
#   or_next_if_better
# endmatch
#
# match $__XILINX_RAMB36_SDP1
#   min efficiency 20
# endmatch