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
48with System.VxWorks;
49
50package 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
189private
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");
205end Interfaces.VxWorks;
206