rdi_cp.h

做ARM仿真器和调试器的厂商需要RDI协议

/* RDI co-processor interface
   Copyright (C) 2001 Free Software Foundation, Inc.


This file is part of GDB.


GDB is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 2, or (at your option) any later
version.


GDB is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.


You should have received a copy of the GNU General Public License
along with GDB; see the file COPYING.  If not, write to the Free
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA.  */


/*
 * RCS $Revision: 1.2 $
 * Checkin $Date: 1998/03/26 17:13:03 $
 * Revising $Author: mwilliam $
 */

#ifndef rdi_cp_h
#define rdi_cp_h

#define RDI_Access_Readable   1
#define RDI_Access_Writable   2 
#define RDI_Access_CPDT       4 /* Register accesses via CP data transfer */
#define RDI_Access_Scan_Chain 8 /* OR'ing this bit will cause the CP Register
                                 * in question to be access via the JTAG 
                                 * interface to a scan chain, only if the 
                                 * Debug agent supports this.
                                 */

typedef struct {
    unsigned short rmin, rmax;
    /* a single description can be used for a range of registers with
       the same properties *accessed via CPDT instructions*
       Because CP15 registers are specified by the CRn part of the
       MRC/MCR Instructions => they must be encoded separately and
       cannot be specified in a range.
     */
    unsigned int nbytes;   /* size of register */
    unsigned char access;  /* see above (Access_xxx) */
    union {
        /* The CPRT Part must appear first since it has more elements
         * and the C init. rules say that in a constant union initialisation
         * the value of the constant expression is assigned to the 
         * first member of the union
         */
       struct { /* CPRT instructions have much more latitude.  The bits fixed
                   by the ARM are  24..31 (condition mask & opcode)
                                   20 (direction)
                                   8..15 (cpnum, arm register)
                                   4 (CPRT not CPDO)
                   leaving 14 bits free to the coprocessor (fortunately
                   falling within two bytes).
                   These are encoded as follows:

                   Bit Pattern for MRC/MCR Instructions.
                   
                   31         23      16           7        0
                   +-----------------------------------------+
                   |Cond|1110|OC1|L|CRn | Rd |1111|OC2|1|CRm |
                   +-----------------------------------------+
                                  b1                   b0

                   b0 = Bits[0:7], b1 = Bits[16:23]
                   => b0 = CRm | ( OpCode2 << 5 )
                      b1 = CRn | ( OpCode1 << 5 )
                 */
                unsigned char read_b0, read_b1,
                              write_b0, write_b1;
              } cprt;
        struct { /* CPDT instructions do not allow the 
                    coprocessor much freedom:
                    only bit 22 ('N') and 12-15 ('CRd') are free for the
                    coprocessor to use as it sees fit.
                 */
                unsigned char nbit;
                unsigned char rdbits;
              } cpdt;
    } accessinst;
} RDI_CoProRegDesc;

typedef struct RDI_CoProDesc RDI_CoProDesc;

/*
 * Define RDI_DontDefineCoProDesc for the actual structure to not
 * be defined. (Allows you to define your own, saving a couple of
 * casts. Not recommended.
 */

/* This horrible long name for backwards compatibility */
#ifdef DONT_USE_DBG_CP_HEADER_DEFINITION_OF_DBG_COPRODESC
#define RDI_DontDefineCoProDesc
#endif

#ifndef RDI_DontDefineCoProDesc
struct RDI_CoProDesc {
    int entries;
    RDI_CoProRegDesc regdesc[1/* really nentries */];
};
#endif /* RDI_DontDefineCoProDesc */

#define RDI_CoProDesc_Size(n) \
  (sizeof(RDI_CoProDesc) + ((n)-1)*sizeof(RDI_CoProRegDesc))

#endif