/*
* programming notes:
*
* the ie chip operates in a 24 bit address space.
*
* most ie interfaces appear to be divided into two parts:
* - generic 586 stuff
* - board specific
*
* generic:
* the generic stuff of the ie chip is all done with data structures
* that live in the chip's memory address space. the chip expects
* its main data structure (the sys conf ptr -- SCP) to be at a fixed
* address in its 24 bit space: 0xfffff4
*
* the SCP points to another structure called the ISCP.
* the ISCP points to another structure called the SCB.
* the SCB has a status field, a linked list of "commands", and
* a linked list of "receive buffers". these are data structures that
* live in memory, not registers.
*
* board:
* to get the chip to do anything, you first put a command in the
* command data structure list. then you have to signal "attention"
* to the chip to get it to look at the command. how you
* signal attention depends on what board you have... on PC's
* there is an i/o port number to do this, on sun's there is a
* register bit you toggle.
*
* to get data from the chip you program it to interrupt...
*
*
* sun issues:
*
* there are 3 kinds of sun "ie" interfaces:
* 1 - a VME/multibus card
* 2 - an on-board interface (sun3's, sun-4/100's, and sun-4/200's)
* 3 - another VME board called the 3E
*
* the VME boards lives in vme16 space. only 16 and 8 bit accesses
* are allowed, so functions that copy data must be aware of this.
*
* the chip is an intel chip. this means that the byte order
* on all the "short"s in the chip's data structures is wrong.
* so, constants described in the intel docs are swapped for the sun.
* that means that any buffer pointers you give the chip must be
* swapped to intel format. yuck.
*
* VME/multibus interface:
* for the multibus interface the board ignores the top 4 bits
* of the chip address. the multibus interface seems to have its
* own MMU like page map (without protections or valid bits, etc).
* there are 256 pages of physical memory on the board (each page
* is 1024 bytes). there are 1024 slots in the page map. so,
* a 1024 byte page takes up 10 bits of address for the offset,
* and if there are 1024 slots in the page that is another 10 bits
* of the address. that makes a 20 bit address, and as stated
* earlier the board ignores the top 4 bits, so that accounts
* for all 24 bits of address.
*
* note that the last entry of the page map maps the top of the
* 24 bit address space and that the SCP is supposed to be at
* 0xfffff4 (taking into account alignment). so,
* for multibus, that entry in the page map has to be used for the SCP.
*
* the page map effects BOTH how the ie chip sees the
* memory, and how the host sees it.
*
* the page map is part of the "register" area of the board
*
* on-board interface:
*
* <fill in useful info later>
*
*
* VME3E interface:
*
* <fill in useful info later>
*
*/
/*
* PART 1: VME/multibus defs
*/
#define IEVME_PAGESIZE 1024 /* bytes */
#define IEVME_PAGSHIFT 10 /* bits */
#define IEVME_NPAGES 256 /* number of pages on chip */
#define IEVME_MAPSZ 1024 /* number of entries in the map */
/*
* PTE for the page map
*/
#define IEVME_SBORDR 0x8000 /* sun byte order */
#define IEVME_IBORDR 0x0000 /* intel byte order */
#define IEVME_P2MEM 0x2000 /* memory is on P2 */
#define IEVME_OBMEM 0x0000 /* memory is on board */
#define IEVME_PGMASK 0x0fff /* gives the physical page frame number */
struct ievme {
u_short pgmap[IEVME_MAPSZ];
u_short xxx[32]; /* prom */
u_short status; /* see below for bits */
u_short xxx2; /* filler */
u_short pectrl; /* parity control (see below) */
u_short peaddr; /* low 16 bits of address */
};
/*
* status bits
*/
#define IEVME_RESET 0x8000 /* reset board */
#define IEVME_ONAIR 0x4000 /* go out of loopback 'on-air' */
#define IEVME_ATTEN 0x2000 /* attention */
#define IEVME_IENAB 0x1000 /* interrupt enable */
#define IEVME_PEINT 0x0800 /* parity error interrupt enable */
#define IEVME_PERR 0x0200 /* parity error flag */
#define IEVME_INT 0x0100 /* interrupt flag */
#define IEVME_P2EN 0x0020 /* enable p2 bus */
#define IEVME_256K 0x0010 /* 256kb rams */
#define IEVME_HADDR 0x000f /* mask for bits 17-20 of address */
/*
* parity control
*/
#define IEVME_PARACK 0x0100 /* parity error ack */
#define IEVME_PARSRC 0x0080 /* parity error source */
#define IEVME_PAREND 0x0040 /* which end of the data got the error */
#define IEVME_PARADR 0x000f /* mask to get bits 17-20 of parity address */
/*
* PART 2: the on-board interface
*/
struct ieob {
u_char obctrl;
};
#define IEOB_NORSET 0x80 /* don't reset the board */
#define IEOB_ONAIR 0x40 /* put us on the air */
#define IEOB_ATTEN 0x20 /* attention! */
#define IEOB_IENAB 0x10 /* interrupt enable */
#define IEOB_XXXXX 0x08 /* free bit */
#define IEOB_XCVRL2 0x04 /* level 2 transceiver? */
#define IEOB_BUSERR 0x02 /* bus error */
#define IEOB_INT 0x01 /* interrupt */
