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) 1999-2010, AdaCore                     --
  10 --                                                                          --
  11 -- GNAT 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 3,  or (at your option) any later ver- --
  14 -- sion.  GNAT 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.                                     --
  17 --                                                                          --
  18 -- As a special exception under Section 7 of GPL version 3, you are granted --
  19 -- additional permissions described in the GCC Runtime Library Exception,   --
  20 -- version 3.1, as published by the Free Software Foundation.               --
  21 --                                                                          --
  22 -- You should have received a copy of the GNU General Public License and    --
  23 -- a copy of the GCC Runtime Library Exception along with this program;     --
  24 -- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
  25 -- <http://www.gnu.org/licenses/>.                                          --
  26 --                                                                          --
  27 -- GNARL was developed by the GNARL team at Florida State University.       --
  28 -- Extensive contributions were provided by Ada Core Technologies, Inc.     --
  29 --                                                                          --
  30 ------------------------------------------------------------------------------
  31
  32 --  This package provides a limited binding to the VxWorks API
  33 --  In particular, it interfaces with the VxWorks hardware interrupt
  34 --  facilities, allowing the use of low-latency direct-vectored
  35 --  interrupt handlers. Note that such handlers have a variety of
  36 --  restrictions regarding system calls and language constructs. In particular,
  37 --  the use of exception handlers and functions returning variable-length
  38 --  objects cannot be used. Less restrictive, but higher-latency handlers can
  39 --  be written using Ada protected procedures, Ada 83 style interrupt entries,
  40 --  or by signalling an Ada task from within an interrupt handler using a
  41 --  binary semaphore as described in the VxWorks Programmer's Manual.
  42 --
  43 --  For complete documentation of the operations in this package, please
  44 --  consult the VxWorks Programmer's Manual and VxWorks Reference Manual.
  45
  46 pragma Warnings (Off, "*foreign convention*");
  47 pragma Warnings (Off, "*add Convention pragma*");
  48 --  These are temporary pragmas to suppress warnings about mismatching
  49 --  conventions, which will be a problem when we get rid of trampolines ???
  50
  51 with System.VxWorks;
  52
  53 package Interfaces.VxWorks is
  54    pragma Preelaborate;
  55
  56    ------------------------------------------------------------------------
  57    --  Here is a complete example that shows how to handle the Interrupt 0x14
  58    --  with a direct-vectored interrupt handler in Ada using this package:
  59
  60    --  with Interfaces.VxWorks; use Interfaces.VxWorks;
  61    --  with System;
  62    --
  63    --  package P is
  64    --
  65    --     Count : Integer;
  66    --     pragma Atomic (Count);
  67    --
  68    --     Level : constant := 1;
  69    --     --  Interrupt level used by this example
  70    --
  71    --     procedure Handler (parameter : System.Address);
  72    --
  73    --  end P;
  74    --
  75    --  package body P is
  76    --
  77    --     procedure Handler (parameter : System.Address) is
  78    --        S : STATUS;
  79    --     begin
  80    --        Count := Count + 1;
  81    --        logMsg ("received an interrupt" & ASCII.LF & ASCII.NUL);
  82    --
  83    --        --  Acknowledge VME interrupt
  84    --        S := sysBusIntAck (intLevel => Level);
  85    --     end Handler;
  86    --  end P;
  87    --
  88    --  with Interfaces.VxWorks; use Interfaces.VxWorks;
  89    --  with Ada.Text_IO; use Ada.Text_IO;
  90    --
  91    --  with P; use P;
  92    --  procedure Useint is
  93    --     --  Be sure to use a reasonable interrupt number for the target
  94    --     --  board!
  95    --     --  This one is the unused VME graphics interrupt on the PPC MV2604
  96    --     Interrupt : constant := 16#14#;
  97    --
  98    --     task T;
  99    --
 100    --     S : STATUS;
 101    --
 102    --     task body T is
 103    --     begin
 104    --        loop
 105    --           Put_Line ("Generating an interrupt...");
 106    --           delay 1.0;
 107    --
 108    --           --  Generate VME interrupt, using interrupt number
 109    --           S := sysBusIntGen (1, Interrupt);
 110    --        end loop;
 111    --     end T;
 112    --
 113    --  begin
 114    --     S := sysIntEnable (intLevel => Level);
 115    --     S := intConnect (INUM_TO_IVEC (Interrupt), handler'Access);
 116    --
 117    --     loop
 118    --        delay 2.0;
 119    --        Put_Line ("value of count:" & P.Count'Img);
 120    --     end loop;
 121    --  end Useint;
 122    -------------------------------------
 123
 124    subtype int is Integer;
 125
 126    type STATUS is new int;
 127    --  Equivalent of the C type STATUS
 128
 129    OK    : constant STATUS := 0;
 130    ERROR : constant STATUS := -1;
 131
 132    type VOIDFUNCPTR is access procedure (parameter : System.Address);
 133    type Interrupt_Vector is new System.Address;
 134    type Exception_Vector is new System.Address;
 135
 136    function intConnect
 137      (vector    : Interrupt_Vector;
 138       handler   : VOIDFUNCPTR;
 139       parameter : System.Address := System.Null_Address) return STATUS;
 140    --  Binding to the C routine intConnect. Use this to set up an
 141    --  user handler. The routine generates a wrapper around the user
 142    --  handler to save and restore context
 143
 144    function intContext return int;
 145    --  Binding to the C routine intContext. This function returns 1 only
 146    --  if the current execution state is in interrupt context.
 147
 148    function intVecGet
 149      (Vector : Interrupt_Vector) return VOIDFUNCPTR;
 150    --  Binding to the C routine intVecGet. Use this to get the
 151    --  existing handler for later restoral
 152
 153    procedure intVecSet
 154      (Vector  : Interrupt_Vector;
 155       Handler : VOIDFUNCPTR);
 156    --  Binding to the C routine intVecSet. Use this to restore a
 157    --  handler obtained using intVecGet
 158
 159    function INUM_TO_IVEC (intNum : int) return Interrupt_Vector;
 160    --  Equivalent to the C macro INUM_TO_IVEC used to convert an interrupt
 161    --  number to an interrupt vector
 162
 163    function sysIntEnable (intLevel : int) return STATUS;
 164    --  Binding to the C routine sysIntEnable
 165
 166    function sysIntDisable (intLevel : int) return STATUS;
 167    --  Binding to the C routine sysIntDisable
 168
 169    function sysBusIntAck (intLevel : int) return STATUS;
 170    --  Binding to the C routine sysBusIntAck
 171
 172    function sysBusIntGen (intLevel : int; Intnum : int) return STATUS;
 173    --  Binding to the C routine sysBusIntGen. Note that the T2
 174    --  documentation implies that a vector address is the proper
 175    --  argument - it's not. The interrupt number in the range
 176    --  0 .. 255 (for 68K and PPC) is the correct argument.
 177
 178    procedure logMsg
 179      (fmt : String; arg1, arg2, arg3, arg4, arg5, arg6 : int := 0);
 180    --  Binding to the C routine logMsg. Note that it is the caller's
 181    --  responsibility to ensure that fmt is a null-terminated string
 182    --  (e.g logMsg ("Interrupt" & ASCII.NUL))
 183
 184    type FP_CONTEXT is private;
 185    --  Floating point context save and restore. Handlers using floating
 186    --  point must be bracketed with these calls. The pFpContext parameter
 187    --  should be an object of type FP_CONTEXT that is
 188    --  declared local to the handler.
 189
 190    procedure fppRestore (pFpContext : in out FP_CONTEXT);
 191    --  Restore floating point context
 192
 193    procedure fppSave (pFpContext : in out FP_CONTEXT);
 194    --  Save floating point context
 195
 196 private
 197
 198    type FP_CONTEXT is new System.VxWorks.FP_CONTEXT;
 199    --  Target-dependent floating point context type
 200
 201    pragma Import (C, intConnect, "intConnect");
 202    pragma Import (C, intContext, "intContext");
 203    pragma Import (C, intVecGet, "intVecGet");
 204    pragma Import (C, intVecSet, "intVecSet");
 205    pragma Import (C, INUM_TO_IVEC, "__gnat_inum_to_ivec");
 206    pragma Import (C, sysIntEnable, "sysIntEnable");
 207    pragma Import (C, sysIntDisable, "sysIntDisable");
 208    pragma Import (C, sysBusIntAck, "sysBusIntAck");
 209    pragma Import (C, sysBusIntGen, "sysBusIntGen");
 210    pragma Import (C, logMsg, "logMsg");
 211    pragma Import (C, fppRestore, "fppRestore");
 212    pragma Import (C, fppSave, "fppSave");
 213 end Interfaces.VxWorks;