gcc/ada/i-vxwork.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                  GNAT 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) 1999-2008, AdaCore                     --
  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,  51  Franklin  Street,  Fifth  Floor, --
  20 -- Boston, MA 02110-1301, 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 pragma Warnings (Off, "*foreign convention*");
  49 pragma Warnings (Off, "*add Convention pragma*");
  50 --  These are temporary pragmas to suppress warnings about mismatching
  51 --  conventions, which will be a problem when we get rid of trampolines ???
  52
  53 with System.VxWorks;
  54
  55 package Interfaces.VxWorks is
  56    pragma Preelaborate;
  57
  58    ------------------------------------------------------------------------
  59    --  Here is a complete example that shows how to handle the Interrupt 0x14
  60    --  with a direct-vectored interrupt handler in Ada using this package:
  61
  62    --  with Interfaces.VxWorks; use Interfaces.VxWorks;
  63    --  with System;
  64    --
  65    --  package P is
  66    --
  67    --     Count : Integer;
  68    --     pragma Atomic (Count);
  69    --
  70    --     Level : constant := 1;
  71    --     --  Interrupt level used by this example
  72    --
  73    --     procedure Handler (parameter : System.Address);
  74    --
  75    --  end P;
  76    --
  77    --  package body P is
  78    --
  79    --     procedure Handler (parameter : System.Address) is
  80    --        S : STATUS;
  81    --     begin
  82    --        Count := Count + 1;
  83    --        logMsg ("received an interrupt" & ASCII.LF & ASCII.NUL);
  84    --
  85    --        --  Acknowledge VME interrupt
  86    --        S := sysBusIntAck (intLevel => Level);
  87    --     end Handler;
  88    --  end P;
  89    --
  90    --  with Interfaces.VxWorks; use Interfaces.VxWorks;
  91    --  with Ada.Text_IO; use Ada.Text_IO;
  92    --
  93    --  with P; use P;
  94    --  procedure Useint is
  95    --     --  Be sure to use a reasonable interrupt number for the target
  96    --     --  board!
  97    --     --  This one is the unused VME graphics interrupt on the PPC MV2604
  98    --     Interrupt : constant := 16#14#;
  99    --
 100    --     task T;
 101    --
 102    --     S : STATUS;
 103    --
 104    --     task body T is
 105    --     begin
 106    --        loop
 107    --           Put_Line ("Generating an interrupt...");
 108    --           delay 1.0;
 109    --
 110    --           --  Generate VME interrupt, using interrupt number
 111    --           S := sysBusIntGen (1, Interrupt);
 112    --        end loop;
 113    --     end T;
 114    --
 115    --  begin
 116    --     S := sysIntEnable (intLevel => Level);
 117    --     S := intConnect (INUM_TO_IVEC (Interrupt), handler'Access);
 118    --
 119    --     loop
 120    --        delay 2.0;
 121    --        Put_Line ("value of count:" & P.Count'Img);
 122    --     end loop;
 123    --  end Useint;
 124    -------------------------------------
 125
 126    subtype int is Integer;
 127
 128    type STATUS is new int;
 129    --  Equivalent of the C type STATUS
 130
 131    OK    : constant STATUS := 0;
 132    ERROR : constant STATUS := -1;
 133
 134    type VOIDFUNCPTR is access procedure (parameter : System.Address);
 135    type Interrupt_Vector is new System.Address;
 136    type Exception_Vector is new System.Address;
 137
 138    function intConnect
 139      (vector    : Interrupt_Vector;
 140       handler   : VOIDFUNCPTR;
 141       parameter : System.Address := System.Null_Address) return STATUS;
 142    --  Binding to the C routine intConnect. Use this to set up an
 143    --  user handler. The routine generates a wrapper around the user
 144    --  handler to save and restore context
 145
 146    function intContext return int;
 147    --  Binding to the C routine intContext. This function returns 1 only
 148    --  if the current execution state is in interrupt context.
 149
 150    function intVecGet
 151      (Vector : Interrupt_Vector) return VOIDFUNCPTR;
 152    --  Binding to the C routine intVecGet. Use this to get the
 153    --  existing handler for later restoral
 154
 155    procedure intVecSet
 156      (Vector  : Interrupt_Vector;
 157       Handler : VOIDFUNCPTR);
 158    --  Binding to the C routine intVecSet. Use this to restore a
 159    --  handler obtained using intVecGet
 160
 161    function INUM_TO_IVEC (intNum : int) return Interrupt_Vector;
 162    --  Equivalent to the C macro INUM_TO_IVEC used to convert an interrupt
 163    --  number to an interrupt vector
 164
 165    function sysIntEnable (intLevel : int) return STATUS;
 166    --  Binding to the C routine sysIntEnable
 167
 168    function sysIntDisable (intLevel : int) return STATUS;
 169    --  Binding to the C routine sysIntDisable
 170
 171    function sysBusIntAck (intLevel : int) return STATUS;
 172    --  Binding to the C routine sysBusIntAck
 173
 174    function sysBusIntGen (intLevel : int; Intnum : int) return STATUS;
 175    --  Binding to the C routine sysBusIntGen. Note that the T2
 176    --  documentation implies that a vector address is the proper
 177    --  argument - it's not. The interrupt number in the range
 178    --  0 .. 255 (for 68K and PPC) is the correct argument.
 179
 180    procedure logMsg
 181      (fmt : String; arg1, arg2, arg3, arg4, arg5, arg6 : int := 0);
 182    --  Binding to the C routine logMsg. Note that it is the caller's
 183    --  responsibility to ensure that fmt is a null-terminated string
 184    --  (e.g logMsg ("Interrupt" & ASCII.NUL))
 185
 186    type FP_CONTEXT is private;
 187    --  Floating point context save and restore. Handlers using floating
 188    --  point must be bracketed with these calls. The pFpContext parameter
 189    --  should be an object of type FP_CONTEXT that is
 190    --  declared local to the handler.
 191
 192    procedure fppRestore (pFpContext : in out FP_CONTEXT);
 193    --  Restore floating point context
 194
 195    procedure fppSave (pFpContext : in out FP_CONTEXT);
 196    --  Save floating point context
 197
 198 private
 199
 200    type FP_CONTEXT is new System.VxWorks.FP_CONTEXT;
 201    --  Target-dependent floating point context type
 202
 203    pragma Import (C, intConnect, "intConnect");
 204    pragma Import (C, intContext, "intContext");
 205    pragma Import (C, intVecGet, "intVecGet");
 206    pragma Import (C, intVecSet, "intVecSet");
 207    pragma Import (C, INUM_TO_IVEC, "__gnat_inum_to_ivec");
 208    pragma Import (C, sysIntEnable, "sysIntEnable");
 209    pragma Import (C, sysIntDisable, "sysIntDisable");
 210    pragma Import (C, sysBusIntAck, "sysBusIntAck");
 211    pragma Import (C, sysBusIntGen, "sysBusIntGen");
 212    pragma Import (C, logMsg, "logMsg");
 213    pragma Import (C, fppRestore, "fppRestore");
 214    pragma Import (C, fppSave, "fppSave");
 215 end Interfaces.VxWorks;