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/*
* limits.h - definition of machine & system dependent address limits
*
* THIS SOFTWARE IS NOT COPYRIGHTED
*
* The following software is offered for use in the public domain.
* There is no warranty with regard to this software or its performance
* and the user must accept the software "AS IS" with all faults.
*
* THE CONTRIBUTORS DISCLAIM ANY WARRANTIES, EXPRESS OR IMPLIED, WITH
* REGARD TO THIS SOFTWARE INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#ifndef _MEMLIMITS_H_
#define _MEMLIMITS_H_
/*
* The macros in this file are specific to a given implementation.
* The general rules for their construction are as follows:
*
* 1.) is_readable(addr,length) should be true if and only if the
* region starting at the given virtual address can be read
* _without_ causing an exception or other fatal error. Note
* that the stub will use the strictest alignment satisfied
* by _both_ addr and length (e.g., if both are divisible by
* 8 then the region will be read in double-word chunks).
*
* 2.) is_writeable(addr,length) should be true if and only if the
* region starting at the given virtual address can be written
* _without_ causing an exception or other fatal error. Note
* that the stub will use the strictest alignment satisfied
* by _both_ addr and length (e.g., if both are divisible by
* 8 then the region will be written in double-word chunks).
*
* 3.) is-steppable(ptr) whould be true if and only if ptr is the
* address of a writeable region of memory which may contain
* an executable instruction. At a minimum this requires that
* ptr be word-aligned (divisible by 4) and not point to EPROM
* or memory-mapped I/O.
*
* Note: in order to satisfy constraints related to cacheability
* of certain memory subsystems it may be necessary for regions
* of kseg0 and kseg1 which map to the same physical addresses
* to have different readability and/or writeability attributes.
*/
/*
#define K0_LIMIT_FOR_READ (K0BASE+0x18000000)
#define K1_LIMIT_FOR_READ (K1BASE+K1SIZE)
#define is_readable(addr,length) \
(((K0BASE <= addr) && ((addr + length) <= K0_LIMIT_FOR_READ)) \
|| ((K1BASE <= addr) && ((addr + length) <= K1_LIMIT_FOR_READ)))
#define K0_LIMIT_FOR_WRITE (K0BASE+0x08000000)
#define K1_LIMIT_FOR_WRITE (K1BASE+0x1e000000)
#define is_writeable(addr,length) \
(((K0BASE <= addr) && ((addr + length) <= K0_LIMIT_FOR_WRITE)) \
|| ((K1BASE <= addr) && ((addr + length) <= K1_LIMIT_FOR_WRITE)))
#define K0_LIMIT_FOR_STEP (K0BASE+0x08000000)
#define K1_LIMIT_FOR_STEP (K1BASE+0x08000000)
#define is_steppable(ptr) \
((((int)ptr & 0x3) == 0) \
&& (((K0BASE <= (int)ptr) && ((int)ptr < K0_LIMIT_FOR_STEP)) \
|| ((K1BASE <= (int)ptr) && ((int)ptr < K1_LIMIT_FOR_STEP))))
struct memseg
{
unsigned begin, end, opts;
};
#define MEMOPT_READABLE 1
#define MEMOPT_WRITEABLE 2
#define NUM_MEMSEGS 10
int add_memsegment(unsigned,unsigned,int);
int is_readable(unsigned,unsigned);
int is_writeable(unsigned,unsigned);
int is_steppable(unsigned);
*/
#endif /* _MEMLIMITS_H_ */
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