Merge #94

94: Add method to trigger system reset r=japaric a=bergus

Basically taken from CMSIS

Co-authored-by: Bergi <[email protected]>
Co-authored-by: Jorge Aparicio <[email protected]>

Author: 3 people

src/peripheral/scb.rs

@@ -598,3 +598,23 @@ impl SCB {
         }
     }
 }
+
+const SCB_AIRCR_VECTKEY: u32 = 0x05FA << 16;
+const SCB_AIRCR_PRIGROUP_MASK: u32 = 0x5 << 8;
+const SCB_AIRCR_SYSRESETREQ: u32 = 1 << 2;
+
+impl SCB {
+    /// Initiate a system reset request to reset the MCU
+    pub fn system_reset(&mut self) -> ! {
+        ::asm::dsb();
+        unsafe { self.aircr.modify(|r|
+            SCB_AIRCR_VECTKEY | // otherwise the write is ignored
+            r & SCB_AIRCR_PRIGROUP_MASK | // keep priority group unchanged
+            SCB_AIRCR_SYSRESETREQ // set the bit
+        ) };
+        ::asm::dsb();
+        loop { // wait for the reset
+            ::asm::nop(); // avoid rust-lang/rust#28728
+        }
+    }
+}