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------------------------------------------------------------------------------

with HAL; use HAL;

with System.Machine_Code; use System.Machine_Code;

package body nRF.Interrupts is

   Handlers : array (nRF.Interrupts.Interrupt_Name) of Handler
     := (others => null);

   procedure GNAT_IRQ_Handler;
   pragma Export (Asm, GNAT_IRQ_Handler, "__adl_irq_handler");

   ------------------
   -- Set_Priority --
   ------------------

   procedure Set_Priority (Int : Interrupt_Name; Prio : Interrupt_Priority) is
   begin
      Cortex_M.NVIC.Set_Priority (Int'Enum_Rep, Prio);
   end Set_Priority;

   ------------
   -- Enable --
   ------------

   procedure Enable (Int : Interrupt_Name) is
   begin
      Cortex_M.NVIC.Enable_Interrupt (Int'Enum_Rep);
   end Enable;

   -------------
   -- Disable --
   -------------

   procedure Disable (Int : Interrupt_Name) is
   begin
      Cortex_M.NVIC.Disable_Interrupt (Int'Enum_Rep);
   end Disable;

   -------------
   -- Pending --
   -------------

   function Pending (Int : Interrupt_Name) return Boolean is
   begin
      return Cortex_M.NVIC.Pending (Int'Enum_Rep);
   end Pending;

   --------------
   -- Register --
   --------------

   procedure Register (Id  : nRF.Interrupts.Interrupt_Name;
                       Hdl : Handler)
   is
   begin
      Handlers (Id) := Hdl;
   end Register;

   ----------------------
   -- GNAT_IRQ_Handler --
   ----------------------

   procedure GNAT_IRQ_Handler is
      Id  : nRF.Interrupts.Interrupt_Name;
      IPSR : UInt32;
   begin
      Asm ("mrs %0, ipsr",
           UInt32'Asm_Output ("=r", IPSR),
           Volatile => True);

      IPSR := IPSR and 16#FF#;

      Id := nRF.Interrupts.Interrupt_Name'Val (IPSR - 16);

      if Handlers (Id) /= null then
         Handlers (Id).all;
      end if;
   end GNAT_IRQ_Handler;

end nRF.Interrupts;