diff --git a/cloud-hypervisor/src/main.rs b/cloud-hypervisor/src/main.rs
index 996671182..415e7ed92 100644
--- a/cloud-hypervisor/src/main.rs
+++ b/cloud-hypervisor/src/main.rs
@@ -33,8 +33,8 @@ use vmm::vm_config::FwCfgConfig;
 use vmm::vm_config::IvshmemConfig;
 use vmm::vm_config::{
     BalloonConfig, DeviceConfig, DiskConfig, FsConfig, GenericVhostUserConfig, LandlockConfig,
-    NetConfig, NumaConfig, PciSegmentConfig, PmemConfig, RateLimiterGroupConfig, TpmConfig,
-    UserDeviceConfig, VdpaConfig, VmConfig, VsockConfig,
+    NetConfig, NumaConfig, PciSegmentConfig, PlatformConfig, PmemConfig, RateLimiterGroupConfig,
+    TpmConfig, UserDeviceConfig, VdpaConfig, VmConfig, VsockConfig,
 };
 use vmm_sys_util::eventfd::EventFd;
 use vmm_sys_util::signal::block_signal;
@@ -388,7 +388,7 @@ fn get_cli_options_sorted(
         Arg::new("platform")
             .long("platform")
             .help(
-                "num_pci_segments=<num_pci_segments>,iommu_segments=<list_of_segments>,iommu_address_width=<bits>,serial_number=<dmi_device_serial_number>,uuid=<dmi_device_uuid>,oem_strings=<list_of_strings>"
+                PlatformConfig::syntax()
             )
             .num_args(1)
             .group("vm-config"),
diff --git a/vmm/src/config.rs b/vmm/src/config.rs
index fc7eb1b8d..e37809745 100644
--- a/vmm/src/config.rs
+++ b/vmm/src/config.rs
@@ -9,6 +9,7 @@ use std::fs;
 use std::path::PathBuf;
 use std::result;
 use std::str::FromStr;
+use std::sync::LazyLock;
 
 use block::ImageType;
 use clap::ArgMatches;
@@ -798,6 +799,30 @@ impl PciSegmentConfig {
 }
 
 impl PlatformConfig {
+    pub fn syntax() -> &'static str {
+        static SYNTAX: LazyLock<String> = LazyLock::new(|| {
+            let mut syntax = "Platform configuration parameters \
+            \"num_pci_segments=<num_pci_segments>,iommu_segments=<list_of_segments>,\
+            iommu_address_width=<bits>,serial_number=<dmi_device_serial_number>,\
+            uuid=<dmi_device_uuid>,oem_strings=<list_of_strings>"
+                .to_string();
+
+            if cfg!(feature = "tdx") {
+                syntax.push_str(",tdx=on|off");
+            }
+
+            if cfg!(feature = "sev_snp") {
+                syntax.push_str(",sev_snp=on|off");
+            }
+
+            syntax.push('"');
+
+            syntax
+        });
+
+        &SYNTAX
+    }
+
     pub fn parse(platform: &str) -> Result<Self> {
         let mut parser = OptionParser::new();
         parser