Update frequency selection related comments
@@ -68,8 +68,10 @@ class WithFireSimConfigTweaks extends Config(
new WithFireSimSimpleClocks ++
// Required*: When using FireSim-as-top to provide a correct path to the target bootrom source
new WithBootROM ++
- // Optional*: Removing this will require adjusting the UART baud rate and
- // potential target-software changes to properly capture UART output
+ // Optional: This sets the default frequency for all buses in the system to 3.2 GHz
+ // (since unspecified bus frequencies will use the pbus frequency)
+ // This frequency selection matches FireSim's legacy selection and is required
+ // to support 200Gb NIC performance. You may select a smaller value.
new chipyard.config.WithPeripheryBusFrequency(3200.0) ++
// Optional: These three configs put the DRAM memory system in it's own clock domian.
// Removing the first config will result in the FASED timing model running
@@ -93,7 +95,7 @@ class WithFireSimConfigTweaks extends Config(
new testchipip.WithDefaultSerialTL ++
// Optional: Removing this will require using an initramfs under linux
new testchipip.WithBlockDevice ++
- // Required*: Scale default baud rate with periphery bus frequency
+ // Optional: Set a UART baudrate (this selection matches FireSim's historical value)
new chipyard.config.WithUART(BigInt(3686400L)) ++
// Required: Do not support debug module w. JTAG until FIRRTL stops emitting @(posedge ~clock)
new chipyard.config.WithNoDebug
