feat(bootloader-interface): add support for marking when the menu is being display

src/integrations/bootloader_interface.rs

@@ -25,6 +25,11 @@ impl BootloaderInterface {
         Self::mark_time("LoaderTimeExecUSec", timer)
     }
 
+    /// Tell the system that Sprout is about to display the menu.
+    pub fn mark_menu(timer: &PlatformTimer) -> Result<()> {
+        Self::mark_time("LoaderTimeMenuUsec", timer)
+    }
+
     /// Tell the system about the current time as measured by the platform timer.
     /// Sets the variable specified by `key` to the number of microseconds.
     fn mark_time(key: &str, timer: &PlatformTimer) -> Result<()> {

src/main.rs

@@ -285,7 +285,8 @@ fn run() -> Result<()> {
             .context(format!("unable to find entry: {force_boot_entry}"))?
     } else {
         // Delegate to the menu to select an entry to boot.
-        menu::select(menu_timeout, &entries).context("unable to select entry via boot menu")?
+        menu::select(&timer, menu_timeout, &entries)
+            .context("unable to select entry via boot menu")?
     };
 
     // Tell the bootloader interface what the selected entry is.

src/menu.rs

@@ -1,4 +1,6 @@
 use crate::entries::BootableEntry;
+use crate::integrations::bootloader_interface::BootloaderInterface;
+use crate::platform::timer::PlatformTimer;
 use anyhow::{Context, Result, bail};
 use log::info;
 use std::time::Duration;
@@ -162,7 +164,15 @@ fn select_with_input<'a>(
 /// Shows a boot menu to select a bootable entry to boot.
 /// The actual work is done internally in [select_with_input] which is called
 /// within the context of the standard input device.
-pub fn select(timeout: Duration, entries: &[BootableEntry]) -> Result<&BootableEntry> {
+pub fn select<'live>(
+    timer: &'live PlatformTimer,
+    timeout: Duration,
+    entries: &'live [BootableEntry],
+) -> Result<&'live BootableEntry> {
+    // Notify the bootloader interface that we are about to display the menu.
+    BootloaderInterface::mark_menu(timer)
+        .context("unable to mark menu display in bootloader interface")?;
+
     // Acquire the standard input device and run the boot menu.
     uefi::system::with_stdin(move |input| select_with_input(input, timeout, entries))
 }