NAME

ip2mapio, ip2mapmem, ip2unmap − multibus mapping operations

SYNOPSIS

#include <ipII/cpureg.h>

void ip2mapio ()
void ip2mapmem ()
void ip2unmap ()

DESCRIPTION

For the IRIS 2400T, IRIS 2500T, and IRIS series 3000 workstations, the ip2mapio, ip2mapmem, and ip2unmap calls are provided to allow/disallow program access to the multibus.  For the IRIS series 2000 workstations, see phys(2).

The ip2mapio system call allows program access to the entire 65536 bytes of multibus i/o space.  The constant SEG_MBIO defined in <ipII/cpureg.h> defines the address in the user’s virtual memory space where the i/o space will be addressable.  To address a particular register, one need only add the i/o register’s multibus address to the SEG_MBIO constant. 

The ip2mapmem system call allows program access to the entire 16,777,216 bytes of multibus memory space (16 megabytes).  The constant SEG_MBMEM defines the address in the user’s virtual memory space where the multibus memory space will appear.  To address a particular multibus memory location, one need only add the multibus address to the SEG_MBMEM constant. 

The ip2unmap system call disables program access to the multibus i/o space and the multibus memory space simultaneously. 

NOTES

No protection is provided for these calls.  Thus, if a user program enables access to all of the multibus memory, and then proceeds to scribble on multibus memory used by the kernel, bad things will very likely happen. 

Remember - Power tools can be dangerous. 

For a standard configuration of the IP2 processor, the kernel will use the lower 2 megabytes of the multibus memory space, with the remainder available for other use. 

SEE ALSO

phys(2)

Version 3.6  —  December 20, 1987