main: Don't fail on missing uart

The UART driver supports only the 16550a that is only available on QEMU.
Print an error but continue so salus can run on spike and HW.

Signed-off-by: Dylan Reid <[email protected]>

Author: dgreid

src/main.rs

@@ -359,7 +359,6 @@ enum RequiredDeviceProbe {
     Imsic(drivers::imsic::ImsicError),
     Pci(drivers::pci::PciError),
     Reset(drivers::reset::Error),
-    Uart(drivers::uart::Error),
 }
 
 impl Display for RequiredDeviceProbe {
@@ -369,7 +368,6 @@ impl Display for RequiredDeviceProbe {
             Imsic(e) => write!(f, "IMSIC: {:?}", e),
             Pci(e) => write!(f, "PCI: {:?}", e),
             Reset(e) => write!(f, "Reset: {:?}", e),
-            Uart(e) => write!(f, "UART: {:?}", e),
         }
     }
 }
@@ -478,8 +476,9 @@ fn primary_init(hart_id: u64, fdt_addr: u64) -> Result<CpuParams, Error> {
     let hyp_dt = DeviceTree::from(&hyp_fdt).map_err(Error::FdtCreation)?;
 
     // Find the UART and switch to it as the system console.
-    UartDriver::probe_from(&hyp_dt, &mut mem_map)
-        .map_err(|e| Error::RequiredDeviceProbe(RequiredDeviceProbe::Uart(e)))?;
+    if let Err(e) = UartDriver::probe_from(&hyp_dt, &mut mem_map) {
+        println!("Failed to probe UART: {:?}", e);
+    }
 
     // Discover the CPU topology.
     CpuInfo::parse_from(&hyp_dt).map_err(Error::CpuTopologyGeneration)?;