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

--                                                                          --

--                  GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS                --

--                                                                          --

--                      I N T E R F A C E S . V X W O R K S                 --

--                                                                          --

--                                   S p e c                                --

--                                                                          --

--                     Copyright (C) 1999-2008, AdaCore                     --

--                                                                          --

-- GNARL is free software; you can  redistribute it  and/or modify it under --

-- terms of the  GNU General Public License as published  by the Free Soft- --

-- ware  Foundation;  either version 2,  or (at your option) any later ver- --

-- sion. GNARL is distributed in the hope that it will be useful, but WITH- --

-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --

-- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --

-- for  more details.  You should have  received  a copy of the GNU General --

-- Public License  distributed with GNARL; see file COPYING.  If not, write --

-- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --

-- Boston, MA 02110-1301, USA.                                              --

--                                                                          --

-- As a special exception,  if other files  instantiate  generics from this --

-- unit, or you link  this unit with other files  to produce an executable, --

-- this  unit  does not  by itself cause  the resulting  executable  to  be --

-- covered  by the  GNU  General  Public  License.  This exception does not --

-- however invalidate  any other reasons why  the executable file  might be --

-- covered by the  GNU Public License.                                      --

--                                                                          --

-- GNARL was developed by the GNARL team at Florida State University.       --

-- Extensive contributions were provided by Ada Core Technologies, Inc.     --

--                                                                          --

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

--  This package provides a limited binding to the VxWorks API

--  In particular, it interfaces with the VxWorks hardware interrupt

--  facilities, allowing the use of low-latency direct-vectored

--  interrupt handlers. Note that such handlers have a variety of

--  restrictions regarding system calls and language constructs. In particular,

--  the use of exception handlers and functions returning variable-length

--  objects cannot be used. Less restrictive, but higher-latency handlers can

--  be written using Ada protected procedures, Ada 83 style interrupt entries,

--  or by signalling an Ada task from within an interrupt handler using a

--  binary semaphore as described in the VxWorks Programmer's Manual.

--

--  For complete documentation of the operations in this package, please

--  consult the VxWorks Programmer's Manual and VxWorks Reference Manual.

pragma Warnings (Off, "*foreign convention*");

pragma Warnings (Off, "*add Convention pragma*");

--  These are temporary pragmas to suppress warnings about mismatching

--  conventions, which will be a problem when we get rid of trampolines ???

with System.VxWorks;

package Interfaces.VxWorks is

   pragma Preelaborate;

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

   --  Here is a complete example that shows how to handle the Interrupt 0x14

   --  with a direct-vectored interrupt handler in Ada using this package:

   --  with Interfaces.VxWorks; use Interfaces.VxWorks;

   --  with System;

   --

   --  package P is

   --

   --     Count : Integer;

   --     pragma Atomic (Count);

   --

   --     Level : constant := 1;

   --     --  Interrupt level used by this example

   --

   --     procedure Handler (parameter : System.Address);

   --

   --  end P;

   --

   --  package body P is

   --

   --     procedure Handler (parameter : System.Address) is

   --        S : STATUS;

   --     begin

   --        Count := Count + 1;

   --        logMsg ("received an interrupt" & ASCII.LF & ASCII.NUL);

   --

   --        --  Acknowledge VME interrupt

   --        S := sysBusIntAck (intLevel => Level);

   --     end Handler;

   --  end P;

   --

   --  with Interfaces.VxWorks; use Interfaces.VxWorks;

   --  with Ada.Text_IO; use Ada.Text_IO;

   --

   --  with P; use P;

   --  procedure Useint is

   --     --  Be sure to use a reasonable interrupt number for the target

   --     --  board!

   --     --  This one is the unused VME graphics interrupt on the PPC MV2604

   --     Interrupt : constant := 16#14#;

   --

   --     task T;

   --

   --     S : STATUS;

   --

   --     task body T is

   --     begin

   --        loop

   --           Put_Line ("Generating an interrupt...");

   --           delay 1.0;

   --

   --           --  Generate VME interrupt, using interrupt number

   --           S := sysBusIntGen (1, Interrupt);

   --        end loop;

   --     end T;

   --

   --  begin

   --     S := sysIntEnable (intLevel => Level);

   --     S := intConnect (INUM_TO_IVEC (Interrupt), handler'Access);

   --

   --     loop

   --        delay 2.0;

   --        Put_Line ("value of count:" & P.Count'Img);

   --     end loop;

   --  end Useint;

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

   subtype int is Integer;

   type STATUS is new int;

   --  Equivalent of the C type STATUS

   OK    : constant STATUS := 0;

   ERROR : constant STATUS := -1;

   type VOIDFUNCPTR is access procedure (parameter : System.Address);

   type Interrupt_Vector is new System.Address;

   type Exception_Vector is new System.Address;

   function intConnect

     (vector    : Interrupt_Vector;

      handler   : VOIDFUNCPTR;

      parameter : System.Address := System.Null_Address) return STATUS;

   --  Binding to the C routine intConnect. Use this to set up an

   --  user handler. The routine generates a wrapper around the user

   --  handler to save and restore context

   function intContext return int;

   --  Binding to the C routine intContext. This function returns 1 only

   --  if the current execution state is in interrupt context.

   function intVecGet

     (Vector : Interrupt_Vector) return VOIDFUNCPTR;

   --  Binding to the C routine intVecGet. Use this to get the

   --  existing handler for later restoral

   procedure intVecSet

     (Vector  : Interrupt_Vector;

      Handler : VOIDFUNCPTR);

   --  Binding to the C routine intVecSet. Use this to restore a

   --  handler obtained using intVecGet

   function INUM_TO_IVEC (intNum : int) return Interrupt_Vector;

   --  Equivalent to the C macro INUM_TO_IVEC used to convert an interrupt

   --  number to an interrupt vector

   function sysIntEnable (intLevel : int) return STATUS;

   --  Binding to the C routine sysIntEnable

   function sysIntDisable (intLevel : int) return STATUS;

   --  Binding to the C routine sysIntDisable

   function sysBusIntAck (intLevel : int) return STATUS;

   --  Binding to the C routine sysBusIntAck

   function sysBusIntGen (intLevel : int; Intnum : int) return STATUS;

   --  Binding to the C routine sysBusIntGen. Note that the T2

   --  documentation implies that a vector address is the proper

   --  argument - it's not. The interrupt number in the range

   --  0 .. 255 (for 68K and PPC) is the correct argument.

   procedure logMsg

     (fmt : String; arg1, arg2, arg3, arg4, arg5, arg6 : int := 0);

   --  Binding to the C routine logMsg. Note that it is the caller's

   --  responsibility to ensure that fmt is a null-terminated string

   --  (e.g logMsg ("Interrupt" & ASCII.NUL))

   type FP_CONTEXT is private;

   --  Floating point context save and restore. Handlers using floating

   --  point must be bracketed with these calls. The pFpContext parameter

   --  should be an object of type FP_CONTEXT that is

   --  declared local to the handler.

   procedure fppRestore (pFpContext : in out FP_CONTEXT);

   --  Restore floating point context

   procedure fppSave (pFpContext : in out FP_CONTEXT);

   --  Save floating point context

private

   type FP_CONTEXT is new System.VxWorks.FP_CONTEXT;

   --  Target-dependent floating point context type

   pragma Import (C, intConnect, "intConnect");

   pragma Import (C, intContext, "intContext");

   pragma Import (C, intVecGet, "intVecGet");

   pragma Import (C, intVecSet, "intVecSet");

   pragma Import (C, INUM_TO_IVEC, "__gnat_inum_to_ivec");

   pragma Import (C, sysIntEnable, "sysIntEnable");

   pragma Import (C, sysIntDisable, "sysIntDisable");

   pragma Import (C, sysBusIntAck, "sysBusIntAck");

   pragma Import (C, sysBusIntGen, "sysBusIntGen");

   pragma Import (C, logMsg, "logMsg");

   pragma Import (C, fppRestore, "fppRestore");

   pragma Import (C, fppSave, "fppSave");

end Interfaces.VxWorks;