# SDC constraints for ldpc_decoder_top # Adapted from Caravel user_proj_example SDC # Target: 50 MHz (20 ns period) ### Note: # - input clock transition and latency are set for clk port. # - IO ports are assumed to be asynchronous (IO_SYNC=0). #------------------------------------------# # Pre-defined Constraints #------------------------------------------# set ::env(IO_SYNC) 0 # Clock network if {[info exists ::env(CLOCK_PORT)] && $::env(CLOCK_PORT) != ""} { set clk_input $::env(CLOCK_PORT) create_clock [get_ports $clk_input] -name clk -period $::env(CLOCK_PERIOD) puts "\[INFO\]: Creating clock {clk} for port $clk_input with period: $::env(CLOCK_PERIOD)" } else { set clk_input __VIRTUAL_CLK__ create_clock -name clk -period $::env(CLOCK_PERIOD) puts "\[INFO\]: Creating virtual clock with period: $::env(CLOCK_PERIOD)" } if { ![info exists ::env(SYNTH_CLK_DRIVING_CELL)] } { set ::env(SYNTH_CLK_DRIVING_CELL) $::env(SYNTH_DRIVING_CELL) } if { ![info exists ::env(SYNTH_CLK_DRIVING_CELL_PIN)] } { set ::env(SYNTH_CLK_DRIVING_CELL_PIN) $::env(SYNTH_DRIVING_CELL_PIN) } # Clock non-idealities set_propagated_clock [all_clocks] set_clock_uncertainty $::env(SYNTH_CLOCK_UNCERTAINTY) [get_clocks {clk}] puts "\[INFO\]: Setting clock uncertainity to: $::env(SYNTH_CLOCK_UNCERTAINTY)" set_clock_transition $::env(SYNTH_CLOCK_TRANSITION) [get_clocks {clk}] puts "\[INFO\]: Setting clock transition to: $::env(SYNTH_CLOCK_TRANSITION)" # Maximum transition time for the design nets set_max_transition $::env(MAX_TRANSITION_CONSTRAINT) [current_design] puts "\[INFO\]: Setting maximum transition to: $::env(MAX_TRANSITION_CONSTRAINT)" # Maximum fanout set_max_fanout $::env(MAX_FANOUT_CONSTRAINT) [current_design] puts "\[INFO\]: Setting maximum fanout to: $::env(MAX_FANOUT_CONSTRAINT)" # Timing paths delays derate set_timing_derate -early [expr {1-$::env(SYNTH_TIMING_DERATE)}] set_timing_derate -late [expr {1+$::env(SYNTH_TIMING_DERATE)}] puts "\[INFO\]: Setting timing derate to: [expr {$::env(SYNTH_TIMING_DERATE) * 100}] %" # Reset input delay set_input_delay [expr $::env(CLOCK_PERIOD) * 0.5] -clock [get_clocks {clk}] [get_ports {rst_n}] # Multicycle paths for Wishbone handshake set_multicycle_path -setup 2 -through [get_ports {wb_ack_o}] set_multicycle_path -hold 1 -through [get_ports {wb_ack_o}] set_multicycle_path -setup 2 -through [get_ports {wb_cyc_i}] set_multicycle_path -hold 1 -through [get_ports {wb_cyc_i}] set_multicycle_path -setup 2 -through [get_ports {wb_stb_i}] set_multicycle_path -hold 1 -through [get_ports {wb_stb_i}] #------------------------------------------# # Retrieved Constraints (from Caravel) #------------------------------------------# # Clock source latency set clk_max_latency 5.57 set clk_min_latency 4.65 set_clock_latency -source -max $clk_max_latency [get_clocks {clk}] set_clock_latency -source -min $clk_min_latency [get_clocks {clk}] puts "\[INFO\]: Setting clock latency range: $clk_min_latency : $clk_max_latency" # Clock input Transition set clk_tran 0.61 set_input_transition $clk_tran [get_ports $clk_input] puts "\[INFO\]: Setting clock transition: $clk_tran" # Input delays (scaled from Caravel characterization) set_input_delay -max 3.17 -clock [get_clocks {clk}] [get_ports {wb_sel_i[*]}] set_input_delay -max 3.74 -clock [get_clocks {clk}] [get_ports {wb_we_i}] set_input_delay -max 3.89 -clock [get_clocks {clk}] [get_ports {wb_adr_i[*]}] set_input_delay -max 4.13 -clock [get_clocks {clk}] [get_ports {wb_stb_i}] set_input_delay -max 4.61 -clock [get_clocks {clk}] [get_ports {wb_dat_i[*]}] set_input_delay -max 4.74 -clock [get_clocks {clk}] [get_ports {wb_cyc_i}] set_input_delay -min 0.79 -clock [get_clocks {clk}] [get_ports {wb_adr_i[*]}] set_input_delay -min 1.04 -clock [get_clocks {clk}] [get_ports {wb_dat_i[*]}] set_input_delay -min 1.19 -clock [get_clocks {clk}] [get_ports {wb_sel_i[*]}] set_input_delay -min 1.65 -clock [get_clocks {clk}] [get_ports {wb_we_i}] set_input_delay -min 1.69 -clock [get_clocks {clk}] [get_ports {wb_cyc_i}] set_input_delay -min 1.86 -clock [get_clocks {clk}] [get_ports {wb_stb_i}] # Input Transition set_input_transition -max 0.14 [get_ports {wb_we_i}] set_input_transition -max 0.15 [get_ports {wb_stb_i}] set_input_transition -max 0.17 [get_ports {wb_cyc_i}] set_input_transition -max 0.18 [get_ports {wb_sel_i[*]}] set_input_transition -max 0.84 [get_ports {wb_dat_i[*]}] set_input_transition -max 0.92 [get_ports {wb_adr_i[*]}] set_input_transition -min 0.07 [get_ports {wb_adr_i[*]}] set_input_transition -min 0.07 [get_ports {wb_dat_i[*]}] set_input_transition -min 0.09 [get_ports {wb_cyc_i}] set_input_transition -min 0.09 [get_ports {wb_sel_i[*]}] set_input_transition -min 0.09 [get_ports {wb_we_i}] set_input_transition -min 0.15 [get_ports {wb_stb_i}] # Output delays set_output_delay -max 0.7 -clock [get_clocks {clk}] [get_ports {irq_o}] set_output_delay -max 3.62 -clock [get_clocks {clk}] [get_ports {wb_dat_o[*]}] set_output_delay -max 8.41 -clock [get_clocks {clk}] [get_ports {wb_ack_o}] set_output_delay -min 0 -clock [get_clocks {clk}] [get_ports {irq_o}] set_output_delay -min 1.13 -clock [get_clocks {clk}] [get_ports {wb_dat_o[*]}] set_output_delay -min 1.37 -clock [get_clocks {clk}] [get_ports {wb_ack_o}] # Output loads set_load 0.19 [all_outputs]