plic: Fix invalid context pointer alignment

1 files changed, 4 insertions, 3 deletions

diff --git a/src/plic.zig b/src/plic.zig
index 7ba6522..3529cb2 100644
--- a/src/plic.zig
+++ b/src/plic.zig
@@ -17,7 +17,6 @@ pub const Error = error{
 };
 
 pub const Context = packed struct {
-    reserved: u32,
     priority_threshold: u32,
     claim: u32,
 };
@@ -28,7 +27,7 @@ pub const Plic = struct {
     const priority_offset = 0x4;
     const enable_offset = 0x2000;
     const context_offset_zero = 0x200000;
-    const context_offset_nonzero = 0x200ffc;
+    const context_offset_nonzero = 0x201000;
 
     pub const num_contexts = 15872;
 
@@ -98,7 +97,9 @@ pub const Plic = struct {
             return @alignCast(@ptrCast(&mmio_slice[context_offset_zero]));
         } else {
             const context_offset: usize = context - 1;
-            return @alignCast(@ptrCast(&mmio_slice[context_offset_nonzero + context_offset * @sizeOf(Context)]));
+            const ptr_offset = context_offset * (@sizeOf(u32) + @sizeOf(Context));
+            const context_ptr = &mmio_slice[context_offset_nonzero + ptr_offset];
+            return @alignCast(@ptrCast(context_ptr));
         }
     }
 };