Merge #1312

1312: Let bootloader partition have read/write/erase operations r=Dirbaio a=rmja

This change should not have any breaking changes.

Co-authored-by: Rasmus Melchior Jacobsen <[email protected]>

1 files changed, 131 insertions, 3 deletions

diff --git a/embassy-boot/boot/src/partition.rs b/embassy-boot/boot/src/partition.rs
index 46f80a23c..3ccd4dd76 100644
--- a/embassy-boot/boot/src/partition.rs
+++ b/embassy-boot/boot/src/partition.rs
@@ -1,10 +1,13 @@
+use embedded_storage::nor_flash::{NorFlash, ReadNorFlash};
+use embedded_storage_async::nor_flash::{NorFlash as AsyncNorFlash, ReadNorFlash as AsyncReadNorFlash};
+
 /// A region in flash used by the bootloader.
 #[derive(Copy, Clone, Debug)]
 #[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct Partition {
-    /// Start of the flash region.
+    /// The offset into the flash where the partition starts.
     pub from: usize,
-    /// End of the flash region.
+    /// The offset into the flash where the partition ends.
     pub to: usize,
 }
 
@@ -14,9 +17,134 @@ impl Partition {
         Self { from, to }
     }
 
-    /// Return the length of the partition
+    /// Return the size of the partition
     #[allow(clippy::len_without_is_empty)]
     pub const fn len(&self) -> usize {
         self.to - self.from
     }
+
+    /// Read from the partition on the provided flash
+    pub(crate) async fn read<F: AsyncReadNorFlash>(
+        &self,
+        flash: &mut F,
+        offset: u32,
+        bytes: &mut [u8],
+    ) -> Result<(), F::Error> {
+        let offset = self.from as u32 + offset;
+        flash.read(offset, bytes).await
+    }
+
+    /// Write to the partition on the provided flash
+    pub(crate) async fn write<F: AsyncNorFlash>(
+        &self,
+        flash: &mut F,
+        offset: u32,
+        bytes: &[u8],
+    ) -> Result<(), F::Error> {
+        let offset = self.from as u32 + offset;
+        flash.write(offset, bytes).await?;
+        trace!("Wrote from 0x{:x} len {}", offset, bytes.len());
+        Ok(())
+    }
+
+    /// Erase part of the partition on the provided flash
+    pub(crate) async fn erase<F: AsyncNorFlash>(&self, flash: &mut F, from: u32, to: u32) -> Result<(), F::Error> {
+        let from = self.from as u32 + from;
+        let to = self.from as u32 + to;
+        flash.erase(from, to).await?;
+        trace!("Erased from 0x{:x} to 0x{:x}", from, to);
+        Ok(())
+    }
+
+    /// Erase the entire partition
+    pub(crate) async fn wipe<F: AsyncNorFlash>(&self, flash: &mut F) -> Result<(), F::Error> {
+        let from = self.from as u32;
+        let to = self.to as u32;
+        flash.erase(from, to).await?;
+        trace!("Wiped from 0x{:x} to 0x{:x}", from, to);
+        Ok(())
+    }
+
+    /// Read from the partition on the provided flash
+    pub(crate) fn read_blocking<F: ReadNorFlash>(
+        &self,
+        flash: &mut F,
+        offset: u32,
+        bytes: &mut [u8],
+    ) -> Result<(), F::Error> {
+        let offset = self.from as u32 + offset;
+        flash.read(offset, bytes)
+    }
+
+    /// Write to the partition on the provided flash
+    pub(crate) fn write_blocking<F: NorFlash>(&self, flash: &mut F, offset: u32, bytes: &[u8]) -> Result<(), F::Error> {
+        let offset = self.from as u32 + offset;
+        flash.write(offset, bytes)?;
+        trace!("Wrote from 0x{:x} len {}", offset, bytes.len());
+        Ok(())
+    }
+
+    /// Erase part of the partition on the provided flash
+    pub(crate) fn erase_blocking<F: NorFlash>(&self, flash: &mut F, from: u32, to: u32) -> Result<(), F::Error> {
+        let from = self.from as u32 + from;
+        let to = self.from as u32 + to;
+        flash.erase(from, to)?;
+        trace!("Erased from 0x{:x} to 0x{:x}", from, to);
+        Ok(())
+    }
+
+    /// Erase the entire partition
+    pub(crate) fn wipe_blocking<F: NorFlash>(&self, flash: &mut F) -> Result<(), F::Error> {
+        let from = self.from as u32;
+        let to = self.to as u32;
+        flash.erase(from, to)?;
+        trace!("Wiped from 0x{:x} to 0x{:x}", from, to);
+        Ok(())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::tests::MemFlash;
+    use crate::Partition;
+
+    #[test]
+    fn can_erase() {
+        let mut flash = MemFlash::<1024, 64, 4>([0x00; 1024]);
+        let partition = Partition::new(256, 512);
+
+        partition.erase_blocking(&mut flash, 64, 192).unwrap();
+
+        for (index, byte) in flash.0.iter().copied().enumerate().take(256 + 64) {
+            assert_eq!(0x00, byte, "Index {}", index);
+        }
+
+        for (index, byte) in flash.0.iter().copied().enumerate().skip(256 + 64).take(128) {
+            assert_eq!(0xFF, byte, "Index {}", index);
+        }
+
+        for (index, byte) in flash.0.iter().copied().enumerate().skip(256 + 64 + 128) {
+            assert_eq!(0x00, byte, "Index {}", index);
+        }
+    }
+
+    #[test]
+    fn can_wipe() {
+        let mut flash = MemFlash::<1024, 64, 4>([0x00; 1024]);
+        let partition = Partition::new(256, 512);
+
+        partition.wipe_blocking(&mut flash).unwrap();
+
+        for (index, byte) in flash.0.iter().copied().enumerate().take(256) {
+            assert_eq!(0x00, byte, "Index {}", index);
+        }
+
+        for (index, byte) in flash.0.iter().copied().enumerate().skip(256).take(256) {
+            assert_eq!(0xFF, byte, "Index {}", index);
+        }
+
+        for (index, byte) in flash.0.iter().copied().enumerate().skip(512) {
+            assert_eq!(0x00, byte, "Index {}", index);
+        }
+    }
 }