Add AltFlashLayout for supported F4 chips

3 files changed, 108 insertions, 29 deletions

diff --git a/embassy-stm32/src/flash/common.rs b/embassy-stm32/src/flash/common.rs
index b190a5a07..c239d9673 100644
--- a/embassy-stm32/src/flash/common.rs
+++ b/embassy-stm32/src/flash/common.rs
@@ -3,9 +3,7 @@ use embassy_hal_common::{into_ref, PeripheralRef};
 use embassy_sync::blocking_mutex::raw::CriticalSectionRawMutex;
 use embassy_sync::mutex::{Mutex, MutexGuard};
 
-use super::{family, Error, FlashRegion};
-pub use crate::_generated::flash_regions::*;
-pub use crate::pac::{FLASH_BASE, FLASH_SIZE, WRITE_SIZE};
+use super::{family, Error, FlashLayout, FlashRegion, FLASH_BASE, FLASH_SIZE, WRITE_SIZE};
 use crate::Peripheral;
 
 pub struct Flash<'d> {
diff --git a/embassy-stm32/src/flash/f4.rs b/embassy-stm32/src/flash/f4.rs
index cb420c69f..257aae2d0 100644
--- a/embassy-stm32/src/flash/f4.rs
+++ b/embassy-stm32/src/flash/f4.rs
@@ -11,7 +11,82 @@ const MEDIUM_SECTOR_SIZE: u32 = 64 * 1024;
 const LARGE_SECTOR_SIZE: u32 = 128 * 1024;
 const SECOND_BANK_SECTOR_OFFSET: u8 = 12;
 
+#[cfg(any(stm32f427, stm32f429, stm32f437, stm32f439, stm32f469, stm32f479))]
+mod alt_regions {
+    use embassy_hal_common::PeripheralRef;
+    use stm32_metapac::FLASH_SIZE;
+
+    use crate::_generated::flash_regions::{BANK1_REGION1, BANK1_REGION2, BANK1_REGION3};
+    use crate::flash::{Bank1Region1, Bank1Region2, Flash, FlashRegion};
+    use crate::peripherals::FLASH;
+
+    pub const ALT_BANK1_REGION3: FlashRegion = FlashRegion {
+        size: 3 * BANK1_REGION3.erase_size,
+        ..BANK1_REGION3
+    };
+    pub const ALT_BANK2_REGION1: FlashRegion = FlashRegion {
+        base: BANK1_REGION1.base + FLASH_SIZE as u32 / 2,
+        ..BANK1_REGION1
+    };
+    pub const ALT_BANK2_REGION2: FlashRegion = FlashRegion {
+        base: BANK1_REGION2.base + FLASH_SIZE as u32 / 2,
+        ..BANK1_REGION2
+    };
+    pub const ALT_BANK2_REGION3: FlashRegion = FlashRegion {
+        base: BANK1_REGION3.base + FLASH_SIZE as u32 / 2,
+        size: 3 * BANK1_REGION3.erase_size,
+        ..BANK1_REGION3
+    };
+
+    pub type AltBank1Region1 = Bank1Region1;
+    pub type AltBank1Region2 = Bank1Region2;
+    pub struct AltBank1Region3(&'static FlashRegion);
+    pub struct AltBank2Region1(&'static FlashRegion);
+    pub struct AltBank2Region2(&'static FlashRegion);
+    pub struct AltBank2Region3(&'static FlashRegion);
+
+    pub struct AltFlashLayout<'d> {
+        _inner: PeripheralRef<'d, FLASH>,
+        pub bank1_region1: AltBank1Region1,
+        pub bank1_region2: AltBank1Region2,
+        pub bank1_region3: AltBank1Region3,
+        pub bank2_region1: AltBank2Region1,
+        pub bank2_region2: AltBank2Region2,
+        pub bank2_region3: AltBank2Region3,
+    }
+
+    impl<'d> Flash<'d> {
+        pub fn into_alt_regions(self) -> AltFlashLayout<'d> {
+            unsafe { crate::pac::FLASH.optcr().modify(|r| r.set_db1m(true)) };
+            AltFlashLayout {
+                _inner: self.release(),
+                bank1_region1: Bank1Region1(&BANK1_REGION1),
+                bank1_region2: Bank1Region2(&BANK1_REGION2),
+                bank1_region3: AltBank1Region3(&ALT_BANK1_REGION3),
+                bank2_region1: AltBank2Region1(&ALT_BANK2_REGION1),
+                bank2_region2: AltBank2Region2(&ALT_BANK2_REGION2),
+                bank2_region3: AltBank2Region3(&ALT_BANK2_REGION3),
+            }
+        }
+    }
+
+    impl Drop for AltFlashLayout<'_> {
+        fn drop(&mut self) {
+            unsafe {
+                super::lock();
+                crate::pac::FLASH.optcr().modify(|r| r.set_db1m(false))
+            };
+        }
+    }
+}
+
+#[cfg(any(stm32f427, stm32f429, stm32f437, stm32f439, stm32f469, stm32f479))]
+pub use alt_regions::AltFlashLayout;
+
 fn is_dual_bank() -> bool {
+    // let asd: super::Bank1Region1;
+    // let sad = &super::BANK_1_REGION_1;
+
     match FLASH_SIZE / 1024 {
         // 1 MB devices depend on configuration
         1024 => {
diff --git a/embassy-stm32/src/flash/mod.rs b/embassy-stm32/src/flash/mod.rs
index 1e7d4c657..7dc714715 100644
--- a/embassy-stm32/src/flash/mod.rs
+++ b/embassy-stm32/src/flash/mod.rs
@@ -1,5 +1,35 @@
 use embedded_storage::nor_flash::{NorFlashError, NorFlashErrorKind};
 
+#[cfg(flash)]
+mod common;
+
+#[cfg(flash)]
+pub use common::*;
+
+pub use crate::_generated::flash_regions::*;
+pub use crate::pac::{FLASH_BASE, FLASH_SIZE, WRITE_SIZE};
+
+pub struct FlashRegion {
+    pub base: u32,
+    pub size: u32,
+    pub erase_size: u32,
+    pub write_size: u32,
+    pub erase_value: u8,
+}
+
+#[derive(Debug, PartialEq)]
+pub struct FlashSector {
+    pub index: u8,
+    pub start: u32,
+    pub size: u32,
+}
+
+impl Drop for FlashLayout<'_> {
+    fn drop(&mut self) {
+        unsafe { family::lock() };
+    }
+}
+
 #[cfg_attr(any(flash_l0, flash_l1, flash_l4, flash_wl, flash_wb), path = "l.rs")]
 #[cfg_attr(flash_f3, path = "f3.rs")]
 #[cfg_attr(flash_f4, path = "f4.rs")]
@@ -39,32 +69,8 @@ mod family {
     }
 }
 
-#[cfg(flash)]
-mod common;
-
-#[cfg(flash)]
-pub use common::*;
-
-pub struct FlashRegion {
-    pub base: u32,
-    pub size: u32,
-    pub erase_size: u32,
-    pub write_size: u32,
-    pub erase_value: u8,
-}
-
-#[derive(Debug, PartialEq)]
-pub struct FlashSector {
-    pub index: u8,
-    pub start: u32,
-    pub size: u32,
-}
-
-impl Drop for FlashLayout<'_> {
-    fn drop(&mut self) {
-        unsafe { family::lock() };
-    }
-}
+#[allow(unused_imports)]
+pub use family::*;
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "defmt", derive(defmt::Format))]