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) 1999-2018, 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 is the x86 VxWorks version of this package
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
48pragma Warnings (Off, "*foreign convention*");
49pragma Warnings (Off, "*add Convention pragma*");
50
51with System.VxWorks;
52
53package Interfaces.VxWorks is
54   pragma Preelaborate;
55
56   ------------------------------------------------------------------------
57   --  Here is a complete example that shows how to handle the Interrupt 0x33
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   --     procedure Handler (Parameter : System.Address);
69   --
70   --  end P;
71   --
72   --  package body P is
73   --
74   --     procedure Handler (Parameter : System.Address) is
75   --     begin
76   --        Count := Count + 1;
77   --        logMsg ("received an interrupt" & ASCII.LF & ASCII.NUL);
78   --     end Handler;
79   --  end P;
80   --
81   --  with Interfaces.VxWorks; use Interfaces.VxWorks;
82   --  with Ada.Text_IO; use Ada.Text_IO;
83   --  with Ada.Interrupts;
84   --  with Machine_Code; use Machine_Code;
85   --
86   --  with P; use P;
87   --  procedure Useint is
88   --
89   --     --  Be sure to use a reasonable interrupt number for target board.
90   --     --  This one is an unreserved interrupt for the Pentium 3 BSP
91   --
92   --     Interrupt : constant := 16#33#;
93   --
94   --     task T;
95   --
96   --     S : STATUS;
97   --
98   --     task body T is
99   --     begin
100   --        loop
101   --           Put_Line ("Generating an interrupt...");
102   --           delay 1.0;
103   --
104   --           --  Generate interrupt, using interrupt number
105   --
106   --           Asm ("int %0",
107   --                Inputs =>
108   --                  Ada.Interrupts.Interrupt_ID'Asm_Input
109   --                    ("i", Interrupt));
110   --        end loop;
111   --     end T;
112   --
113   --  begin
114   --     S := intConnect (INUM_TO_IVEC (Interrupt), Handler'Access);
115   --
116   --     loop
117   --        delay 2.0;
118   --        Put_Line ("value of count:" & P.Count'Img);
119   --     end loop;
120   --  end Useint;
121   -------------------------------------
122
123   subtype int is Integer;
124
125   type STATUS is new int;
126   --  Equivalent of the C type STATUS
127
128   OK    : constant STATUS := 0;
129   ERROR : constant STATUS := -1;
130
131   type VOIDFUNCPTR is access procedure (parameter : System.Address);
132   type Interrupt_Vector is new System.Address;
133   type Exception_Vector is new System.Address;
134
135   function intConnect
136     (vector    : Interrupt_Vector;
137      handler   : VOIDFUNCPTR;
138      parameter : System.Address := System.Null_Address) return STATUS;
139   --  Binding to the C routine intConnect. Use this to set up an user handler.
140   --  The routine generates a wrapper around the user handler to save and
141   --  restore context
142
143   function intContext return int;
144   --  Binding to the C routine intContext. This function returns 1 only if the
145   --  current execution state is in interrupt context.
146
147   function intVecGet
148     (Vector : Interrupt_Vector) return VOIDFUNCPTR;
149   --  Binding to the C routine intVecGet. Use this to get the existing handler
150   --  for later restoral
151
152   procedure intVecSet
153     (Vector  : Interrupt_Vector;
154      Handler : VOIDFUNCPTR);
155   --  Binding to the C routine intVecSet. Use this to restore a handler
156   --  obtained using intVecGet
157
158   procedure intVecGet2
159     (vector       : Interrupt_Vector;
160      pFunction    : out VOIDFUNCPTR;
161      pIdtGate     : not null access int;
162      pIdtSelector : not null access int);
163   --  Binding to the C routine intVecGet2. Use this to get the existing
164   --  handler for later restoral
165
166   procedure intVecSet2
167     (vector       : Interrupt_Vector;
168      pFunction    : VOIDFUNCPTR;
169      pIdtGate     : not null access int;
170      pIdtSelector : not null access int);
171   --  Binding to the C routine intVecSet2. Use this to restore a
172   --  handler obtained using intVecGet2
173
174   function INUM_TO_IVEC (intNum : int) return Interrupt_Vector;
175   --  Equivalent to the C macro INUM_TO_IVEC used to convert an interrupt
176   --  number to an interrupt vector
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 point
186   --  must be bracketed with these calls. The pFpContext parameter should be
187   --  an object of type FP_CONTEXT that is declared local to the handler.
188   --
189   --  See the VxWorks Intel Architecture Supplement regarding these routines
190
191   procedure fppRestore (pFpContext : in out FP_CONTEXT);
192   --  Restore floating point context - old style
193
194   procedure fppSave (pFpContext : in out FP_CONTEXT);
195   --  Save floating point context - old style
196
197   procedure fppXrestore (pFpContext : in out FP_CONTEXT);
198   --  Restore floating point context - new style
199
200   procedure fppXsave (pFpContext : in out FP_CONTEXT);
201   --  Save floating point context - new style
202
203private
204
205   type FP_CONTEXT is new System.VxWorks.FP_CONTEXT;
206   --  Target-dependent floating point context type
207
208   pragma Import (C, intConnect, "intConnect");
209   pragma Import (C, intContext, "intContext");
210   pragma Import (C, intVecGet, "intVecGet");
211   pragma Import (C, intVecSet, "intVecSet");
212   pragma Import (C, intVecGet2, "intVecGet2");
213   pragma Import (C, intVecSet2, "intVecSet2");
214   pragma Import (C, INUM_TO_IVEC, "__gnat_inum_to_ivec");
215   pragma Import (C, logMsg, "logMsg");
216   pragma Import (C, fppRestore, "fppRestore");
217   pragma Import (C, fppSave, "fppSave");
218   pragma Import (C, fppXrestore, "fppXrestore");
219   pragma Import (C, fppXsave, "fppXsave");
220end Interfaces.VxWorks;
221