diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..526c8a3
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1 @@
+*.sh text eol=lf
\ No newline at end of file
diff --git a/cortex-ar/src/generic_timer/el0.rs b/cortex-ar/src/generic_timer/el0.rs
index ae7ec0d..850babf 100644
--- a/cortex-ar/src/generic_timer/el0.rs
+++ b/cortex-ar/src/generic_timer/el0.rs
@@ -30,11 +30,11 @@ impl super::GenericTimer for El0PhysicalTimer {
         register::Cntfrq::read().0
     }
 
-    fn counter(&mut self) -> u64 {
+    fn counter(&self) -> u64 {
         register::CntPct::read().0
     }
 
-    fn counter_compare(&mut self) -> u64 {
+    fn counter_compare(&self) -> u64 {
         register::CntpCval::read().0
     }
 
@@ -94,11 +94,11 @@ impl super::GenericTimer for El0VirtualTimer {
         register::Cntfrq::read().0
     }
 
-    fn counter(&mut self) -> u64 {
+    fn counter(&self) -> u64 {
         register::CntVct::read().0
     }
 
-    fn counter_compare(&mut self) -> u64 {
+    fn counter_compare(&self) -> u64 {
         register::CntvCval::read().0
     }
 
diff --git a/cortex-ar/src/generic_timer/el1.rs b/cortex-ar/src/generic_timer/el1.rs
index 3013eeb..9af1d90 100644
--- a/cortex-ar/src/generic_timer/el1.rs
+++ b/cortex-ar/src/generic_timer/el1.rs
@@ -38,11 +38,11 @@ impl GenericTimer for El1PhysicalTimer {
         self.0.frequency_hz()
     }
 
-    fn counter(&mut self) -> u64 {
+    fn counter(&self) -> u64 {
         self.0.counter()
     }
 
-    fn counter_compare(&mut self) -> u64 {
+    fn counter_compare(&self) -> u64 {
         self.0.counter_compare()
     }
 
@@ -138,11 +138,11 @@ impl GenericTimer for El1VirtualTimer {
         self.0.frequency_hz()
     }
 
-    fn counter(&mut self) -> u64 {
+    fn counter(&self) -> u64 {
         self.0.counter()
     }
 
-    fn counter_compare(&mut self) -> u64 {
+    fn counter_compare(&self) -> u64 {
         self.0.counter_compare()
     }
 
diff --git a/cortex-ar/src/generic_timer/el2.rs b/cortex-ar/src/generic_timer/el2.rs
index be881fe..89a56e9 100644
--- a/cortex-ar/src/generic_timer/el2.rs
+++ b/cortex-ar/src/generic_timer/el2.rs
@@ -34,11 +34,11 @@ impl GenericTimer for El2PhysicalTimer {
         self.0.frequency_hz()
     }
 
-    fn counter(&mut self) -> u64 {
+    fn counter(&self) -> u64 {
         self.0.counter()
     }
 
-    fn counter_compare(&mut self) -> u64 {
+    fn counter_compare(&self) -> u64 {
         self.0.counter_compare()
     }
 
@@ -105,11 +105,11 @@ impl GenericTimer for El2VirtualTimer {
         self.0.frequency_hz()
     }
 
-    fn counter(&mut self) -> u64 {
+    fn counter(&self) -> u64 {
         self.0.counter()
     }
 
-    fn counter_compare(&mut self) -> u64 {
+    fn counter_compare(&self) -> u64 {
         self.0.counter_compare()
     }
 
@@ -166,11 +166,11 @@ impl super::GenericTimer for El2HypPhysicalTimer {
         register::Cntfrq::read().0
     }
 
-    fn counter(&mut self) -> u64 {
+    fn counter(&self) -> u64 {
         register::CntPct::read().0
     }
 
-    fn counter_compare(&mut self) -> u64 {
+    fn counter_compare(&self) -> u64 {
         register::CnthpCval::read().0
     }
 
diff --git a/cortex-ar/src/generic_timer/mod.rs b/cortex-ar/src/generic_timer/mod.rs
index 75ba046..079f75b 100644
--- a/cortex-ar/src/generic_timer/mod.rs
+++ b/cortex-ar/src/generic_timer/mod.rs
@@ -28,10 +28,10 @@ pub trait GenericTimer {
     ///
     /// Note that speculative reads are allowed and reads may occur out of
     /// order. Add ISB and DSB fences before/after this call as required.
-    fn counter(&mut self) -> u64;
+    fn counter(&self) -> u64;
 
     /// Get the counter compare value.
-    fn counter_compare(&mut self) -> u64;
+    fn counter_compare(&self) -> u64;
 
     /// Set the counter compare value.
     ///