gcc/ada/i-vxwork.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                 GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS              --
   4 --                                                                          --
   5 --                      I N T E R F A C E S . V X W O R K S                 --
   6 --                                                                          --
   7 --                                   S p e c                                --
   8 --                                                                          --
   9 --             Copyright (C) 1999-2003 Ada Core Technologies, Inc.          --
  10 --                                                                          --
  11 -- GNARL is free software; you can  redistribute it  and/or modify it under --
  12 -- terms of the  GNU General Public License as published  by the Free Soft- --
  13 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  14 -- sion. GNARL is distributed in the hope that it will be useful, but WITH- --
  15 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  16 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  17 -- for  more details.  You should have  received  a copy of the GNU General --
  18 -- Public License  distributed with GNARL; see file COPYING.  If not, write --
  19 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  20 -- MA 02111-1307, USA.                                                      --
  21 --                                                                          --
  22 -- As a special exception,  if other files  instantiate  generics from this --
  23 -- unit, or you link  this unit with other files  to produce an executable, --
  24 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  25 -- covered  by the  GNU  General  Public  License.  This exception does not --
  26 -- however invalidate  any other reasons why  the executable file  might be --
  27 -- covered by the  GNU Public License.                                      --
  28 --                                                                          --
  29 -- GNARL was developed by the GNARL team at Florida State University.       --
  30 -- Extensive contributions were provided by Ada Core Technologies, Inc.     --
  31 --                                                                          --
  32 ------------------------------------------------------------------------------
  33
  34 --  This package provides a limited binding to the VxWorks API
  35 --  In particular, it interfaces with the VxWorks hardware interrupt
  36 --  facilities, allowing the use of low-latency direct-vectored
  37 --  interrupt handlers. Note that such handlers have a variety of
  38 --  restrictions regarding system calls and language constructs. In particular,
  39 --  the use of exception handlers and functions returning variable-length
  40 --  objects cannot be used. Less restrictive, but higher-latency handlers can
  41 --  be written using Ada protected procedures, Ada 83 style interrupt entries,
  42 --  or by signalling an Ada task from within an interrupt handler using a
  43 --  binary semaphore as described in the VxWorks Programmer's Manual.
  44 --
  45 --  For complete documentation of the operations in this package, please
  46 --  consult the VxWorks Programmer's Manual and VxWorks Reference Manual.
  47
  48 with System.VxWorks;
  49
  50 package Interfaces.VxWorks is
  51    pragma Preelaborate (VxWorks);
  52
  53    ------------------------------------------------------------------------
  54    --  Here is a complete example that shows how to handle the Interrupt 0x14
  55    --  with a direct-vectored interrupt handler in Ada using this package:
  56
  57    --  with Interfaces.VxWorks; use Interfaces.VxWorks;
  58    --  with System;
  59    --
  60    --  package P is
  61    --
  62    --     Count : Integer;
  63    --     pragma Atomic (Count);
  64    --
  65    --     Level : constant := 1;
  66    --     --  Interrupt level used by this example
  67    --
  68    --     procedure Handler (parameter : System.Address);
  69    --
  70    --  end P;
  71    --
  72    --  package body P is
  73    --
  74    --     procedure Handler (parameter : System.Address) is
  75    --        S : STATUS;
  76    --     begin
  77    --        Count := Count + 1;
  78    --        logMsg ("received an interrupt" & ASCII.LF & ASCII.Nul);
  79    --
  80    --        --  Acknowledge VME interrupt
  81    --        S := sysBusIntAck (intLevel => Level);
  82    --     end Handler;
  83    --  end P;
  84    --
  85    --  with Interfaces.VxWorks; use Interfaces.VxWorks;
  86    --  with Ada.Text_IO; use Ada.Text_IO;
  87    --
  88    --  with P; use P;
  89    --  procedure Useint is
  90    --     --  Be sure to use a reasonable interrupt number for the target
  91    --     --  board!
  92    --     --  This one is the unused VME graphics interrupt on the PPC MV2604
  93    --     Interrupt : constant := 16#14#;
  94    --
  95    --     task T;
  96    --
  97    --     S : STATUS;
  98    --
  99    --     task body T is
 100    --     begin
 101    --        loop
 102    --           Put_Line ("Generating an interrupt...");
 103    --           delay 1.0;
 104    --
 105    --           --  Generate VME interrupt, using interrupt number
 106    --           S := sysBusIntGen (1, Interrupt);
 107    --        end loop;
 108    --     end T;
 109    --
 110    --  begin
 111    --     S := sysIntEnable (intLevel => Level);
 112    --     S := intConnect (INUM_TO_IVEC (Interrupt), handler'Access);
 113    --
 114    --     loop
 115    --        delay 2.0;
 116    --        Put_Line ("value of count:" & P.Count'Img);
 117    --     end loop;
 118    --  end Useint;
 119    -------------------------------------
 120
 121    subtype int is Integer;
 122
 123    type STATUS is new int;
 124    --  Equivalent of the C type STATUS
 125
 126    OK    : constant STATUS := 0;
 127    ERROR : constant STATUS := -1;
 128
 129    type VOIDFUNCPTR is access procedure (parameter : System.Address);
 130    type Interrupt_Vector is new System.Address;
 131    type Exception_Vector is new System.Address;
 132
 133    function intConnect
 134      (vector    : Interrupt_Vector;
 135       handler   : VOIDFUNCPTR;
 136       parameter : System.Address := System.Null_Address) return STATUS;
 137    --  Binding to the C routine intConnect. Use this to set up an
 138    --  user handler. The routine generates a wrapper around the user
 139    --  handler to save and restore context
 140
 141    function intVecGet
 142      (Vector : Interrupt_Vector) return VOIDFUNCPTR;
 143    --  Binding to the C routine intVecGet. Use this to get the
 144    --  existing handler for later restoral
 145
 146    procedure intVecSet
 147      (Vector  : Interrupt_Vector;
 148       Handler : VOIDFUNCPTR);
 149    --  Binding to the C routine intVecSet. Use this to restore a
 150    --  handler obtained using intVecGet
 151
 152    function INUM_TO_IVEC (intNum : int) return Interrupt_Vector;
 153    --  Equivalent to the C macro INUM_TO_IVEC used to convert an interrupt
 154    --  number to an interrupt vector
 155
 156    function sysIntEnable (intLevel : int) return STATUS;
 157    --  Binding to the C routine sysIntEnable
 158
 159    function sysIntDisable (intLevel : int) return STATUS;
 160    --  Binding to the C routine sysIntDisable
 161
 162    function sysBusIntAck (intLevel : int) return STATUS;
 163    --  Binding to the C routine sysBusIntAck
 164
 165    function sysBusIntGen (intLevel : int; Intnum : int) return STATUS;
 166    --  Binding to the C routine sysBusIntGen. Note that the T2
 167    --  documentation implies that a vector address is the proper
 168    --  argument - it's not. The interrupt number in the range
 169    --  0 .. 255 (for 68K and PPC) is the correct agument.
 170
 171    procedure logMsg
 172      (fmt : String; arg1, arg2, arg3, arg4, arg5, arg6 : int := 0);
 173    --  Binding to the C routine logMsg. Note that it is the caller's
 174    --  responsibility to ensure that fmt is a null-terminated string
 175    --  (e.g logMsg ("Interrupt" & ASCII.NUL))
 176
 177    type FP_CONTEXT is private;
 178    --  Floating point context save and restore. Handlers using floating
 179    --  point must be bracketed with these calls. The pFpContext parameter
 180    --  should be an object of type FP_CONTEXT that is
 181    --  declared local to the handler.
 182
 183    procedure fppRestore (pFpContext : in out FP_CONTEXT);
 184    --  Restore floating point context
 185
 186    procedure fppSave (pFpContext : in out FP_CONTEXT);
 187    --  Save floating point context
 188
 189 private
 190
 191    type FP_CONTEXT is new System.VxWorks.FP_CONTEXT;
 192    --  Target-dependent floating point context type
 193
 194    pragma Import (C, intConnect, "intConnect");
 195    pragma Import (C, intVecGet, "intVecGet");
 196    pragma Import (C, intVecSet, "intVecSet");
 197    pragma Import (C, INUM_TO_IVEC, "__gnat_inum_to_ivec");
 198    pragma Import (C, sysIntEnable, "sysIntEnable");
 199    pragma Import (C, sysIntDisable, "sysIntDisable");
 200    pragma Import (C, sysBusIntAck, "sysBusIntAck");
 201    pragma Import (C, sysBusIntGen, "sysBusIntGen");
 202    pragma Import (C, logMsg, "logMsg");
 203    pragma Import (C, fppRestore, "fppRestore");
 204    pragma Import (C, fppSave, "fppSave");
 205 end Interfaces.VxWorks;