zircon/kernel/platform/pc/debug.h

#include <stdint.h>

struct DebugUartInfo {
  enum class Type {
    None,
    Port,
    Mmio,
  };

  uint64_t mem_addr;
  uint32_t io_port;
  uint32_t irq;
  Type type;
};

DebugUartInfo debug_uart_info();