Zynq: Use new default clocks to generate subsystem

* create_subsystem_clocks_and_resets automatically gets freqs
* using now in Zynq, removed manual mem freq computation
* fixed bug in default argument

common/common.tcl

@@ -798,7 +798,8 @@ namespace eval tapasco {
   # @param freqs list of name frequency (MHz) pairs, e.g., [list design 100 memory 250]
   # @param name Name of the subsystem group
   # @return Subsystem group
-  proc create_subsystem_clocks_and_resets {{freqs [get_frequencies]} {name ClockResets}} {
+  proc create_subsystem_clocks_and_resets {{freqs {}} {name ClockResets}} {
+    if {$freqs == {}} { set freqs [get_frequencies] }
     puts "Creating clock and reset subsystem ..."
     puts "  frequencies: $freqs"
     set instance [current_bd_instance .]

platform/zynq/zynq.tcl

@@ -331,15 +331,7 @@ namespace eval platform {
       set ss_host [create_subsystem_host]
 
       # create clocks and resets
-      set mem_freq 200
-      if {[tapasco::get_speed_grade] > -2} {
-        puts "  speed grade: [tapasco::get_speed_grade], reducing mem speed to 158 MHz"
-        set mem_freq 158
-      }
-      set ss_cnr [tapasco::create_subsystem_clocks_and_resets [list \
-          "host" [tapasco::get_design_frequency] \
-          "design" [tapasco::get_design_frequency] \
-          "memory" $mem_freq]]
+      set ss_cnr [tapasco::create_subsystem_clocks_and_resets]
       connect_bd_net [get_bd_pins -filter {TYPE == rst && DIR == O} -of_objects $ss_host] \
           [get_bd_pins -filter {TYPE == rst && DIR == I} -of_objects $ss_cnr]