NetBSD/sys/arch/sparc/dev/zsvar.h
pk ee08e9085b Extend the size of the "soft" FIFOs which reportedly reduces the number
of FIFO overflows on high baud rates.
However, doing so on all 4 ports would cost a whopping 64KB (at 4096 entries
per FIFO) of kernel memory. So, the FIFOs are now allocated at attach time
allowing the size for the keyboard and mouse ports to be reduced (to 128)
which should be adequate for the 1200 baud they use.
1995-11-29 23:41:31 +00:00

164 lines
6.5 KiB
C

/* $NetBSD: zsvar.h,v 1.5 1995/11/29 23:41:31 pk Exp $ */
/*
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This software was developed by the Computer Systems Engineering group
* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
* contributed to Berkeley.
*
* All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Lawrence Berkeley Laboratory.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)zsvar.h 8.1 (Berkeley) 6/11/93
*/
/*
* Software state, per zs channel.
*
* The zs chip has insufficient buffering, so we provide a software
* buffer using a two-level interrupt scheme. The hardware (high priority)
* interrupt simply grabs the `cause' of the interrupt and stuffs it into
* a ring buffer. It then schedules a software interrupt; the latter
* empties the ring as fast as it can, hoping to avoid overflow.
*
* Interrupts can happen because of:
* - received data;
* - transmit pseudo-DMA done; and
* - status change.
* These are all stored together in the (single) ring. The size of the
* ring is a power of two, to make % operations fast. Since we need two
* bits to distinguish the interrupt type, and up to 16 for the received
* data plus RR1 status, we use 32 bits per ring entry.
*
* When the value is a character + RR1 status, the character is in the
* upper 8 bits of the RR1 status.
*/
/* 0 is reserved (means "no interrupt") */
#define ZRING_RINT 1 /* receive data interrupt */
#define ZRING_XINT 2 /* transmit done interrupt */
#define ZRING_SINT 3 /* status change interrupt */
#define ZRING_TYPE(x) ((x) & 3)
#define ZRING_VALUE(x) ((x) >> 8)
#define ZRING_MAKE(t, v) ((t) | (v) << 8)
struct zs_chanstate {
struct zs_chanstate *cs_next; /* linked list for zshard() */
volatile struct zschan *cs_zc; /* points to hardware regs */
int cs_unit; /* unit number */
struct tty *cs_ttyp; /* ### */
/*
* We must keep a copy of the write registers as they are
* mostly write-only and we sometimes need to set and clear
* individual bits (e.g., in WR3). Not all of these are
* needed but 16 bytes is cheap and this makes the addressing
* simpler. Unfortunately, we can only write to some registers
* when the chip is not actually transmitting, so whenever
* we are expecting a `transmit done' interrupt the preg array
* is allowed to `get ahead' of the current values. In a
* few places we must change the current value of a register,
* rather than (or in addition to) the pending value; for these
* cs_creg[] contains the current value.
*/
u_char cs_creg[16]; /* current values */
u_char cs_preg[16]; /* pending values */
u_char cs_heldchange; /* change pending (creg != preg) */
u_char cs_rr0; /* last rr0 processed */
/* pure software data, per channel */
char cs_softcar; /* software carrier */
char cs_conk; /* is console keyboard, decode L1-A */
char cs_brkabort; /* abort (as if via L1-A) on BREAK */
char cs_kgdb; /* enter debugger on frame char */
char cs_consio; /* port does /dev/console I/O */
char cs_xxx; /* (spare) */
int cs_speed; /* default baud rate (from ROM) */
/*
* The transmit byte count and address are used for pseudo-DMA
* output in the hardware interrupt code. PDMA can be suspended
* to get pending changes done; heldtbc is used for this. It can
* also be stopped for ^S; this sets TS_TTSTOP in tp->t_state.
*/
int cs_tbc; /* transmit byte count */
caddr_t cs_tba; /* transmit buffer address */
int cs_heldtbc; /* held tbc while xmission stopped */
/*
* Printing an overrun error message often takes long enough to
* cause another overrun, so we only print one per second.
*/
long cs_rotime; /* time of last ring overrun */
long cs_fotime; /* time of last fifo overrun */
/*
* The ring buffer.
*/
u_int cs_rbget; /* ring buffer `get' index */
volatile u_int cs_rbput; /* ring buffer `put' index */
u_int cs_ringmask; /* mask, reflecting size of `rbuf' */
int *cs_rbuf; /* type, value pairs */
};
/*
* N.B.: the keyboard is channel 1, the mouse channel 0; ttyb is 1, ttya
* is 0. In other words, the things are BACKWARDS.
*/
#define ZS_CHAN_A 1
#define ZS_CHAN_B 0
/*
* Macros to read and write individual registers (except 0) in a channel.
*
* On the SparcStation the 1.6 microsecond recovery time is
* handled in hardware. On the older Sun4 machine it isn't, and
* software must deal with the problem.
*/
#ifdef SUN4
#define ZS_READ(c, r) zs_read(c, r)
#define ZS_WRITE(c, r, v) zs_write(c, r, v)
#if defined(SUN4C) || defined(SUN4M)
#define ZS_DELAY() (cputyp == CPU_SUN4 ? delay(1) : 0)
#else
#define ZS_DELAY() delay(1)
#endif
#else
#define ZS_READ(c, r) ((c)->zc_csr = (r), (c)->zc_csr)
#define ZS_WRITE(c, r, v) ((c)->zc_csr = (r), (c)->zc_csr = (v))
#define ZS_DELAY()
#endif