NetBSD-5.0.2/sys/arch/macppc/dev/zs_kgdb.c
/* $NetBSD: zs_kgdb.c,v 1.8 2008/04/28 20:23:27 martin Exp $ */
/*-
* Copyright (c) 1996 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Gordon W. Ross.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* Hooks for kgdb when attached via the z8530 driver
*
* To use this, build a kernel with: option KGDB, and
* boot that kernel with "-d". (The kernel will call
* zs_kgdb_init, kgdb_connect.) When the console prints
* "kgdb waiting..." you run "gdb -k kernel" and do:
* (gdb) set remotebaud 19200
* (gdb) target remote /dev/ttyb
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: zs_kgdb.c,v 1.8 2008/04/28 20:23:27 martin Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/device.h>
#include <sys/conf.h>
#include <sys/ioctl.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <sys/kgdb.h>
#include <dev/ofw/openfirm.h>
#include <dev/ic/z8530reg.h>
#include <machine/z8530var.h>
static void zs_setparam __P((struct zs_chanstate *, int, int));
static void zskgdb __P((struct zs_chanstate *));
struct zsops zsops_kgdb;
static u_char zs_kgdb_regs[16] = {
0, /* 0: CMD (reset, etc.) */
0, /* 1: ~(ZSWR1_RIE | ZSWR1_TIE | ZSWR1_SIE) */
0, /* IVECT */
ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
0, /* 6: TXSYNC/SYNCLO */
0, /* 7: RXSYNC/SYNCHI */
0, /* 8: alias for data port */
ZSWR9_MASTER_IE,
0, /*10: Misc. TX/RX control bits */
ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
((PCLK/32)/38400)-2, /*12: BAUDLO (default=38400) */
0, /*13: BAUDHI (default=38400) */
ZSWR14_BAUD_ENA,
ZSWR15_BREAK_IE,
};
/*
* This replaces "zs_reset()" in the sparc driver.
*/
static void
zs_setparam(cs, iena, rate)
struct zs_chanstate *cs;
int iena;
int rate;
{
int s, tconst;
bcopy(zs_kgdb_regs, cs->cs_preg, 16);
if (iena) {
cs->cs_preg[1] = ZSWR1_RIE | ZSWR1_SIE;
}
/* Initialize the speed, etc. */
tconst = BPS_TO_TCONST(cs->cs_brg_clk, rate);
cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS;
cs->cs_preg[12] = tconst;
cs->cs_preg[13] = tconst >> 8;
s = splhigh();
zs_loadchannelregs(cs);
splx(s);
}
#ifndef KGDB_DEVNAME
#define KGDB_DEVNAME "scca"
#endif
char *zs_kgdb_devname = KGDB_DEVNAME;
/*
* Set up for kgdb; called at boot time before configuration.
* KGDB interrupts will be enabled later when zs0 is configured.
* Called after cninit(), so printf() etc. works.
*/
void
zs_kgdb_init()
{
extern const struct cdevsw zstty_cdevsw;
struct zs_chanstate cs;
volatile struct zschan *zc;
int escc, escc_ch, obio, zs_offset;
int channel = 0;
u_int32_t reg[5];
char name[16];
if ((escc_ch = OF_finddevice(zs_kgdb_devname)) == -1)
return;
memset(name, 0, sizeof(name));
if (OF_getprop(escc_ch, "device_type", name, sizeof(name)) == -1)
return;
if (strcmp(name, "serial") != 0)
return;
memset(name, 0, sizeof(name));
if (OF_getprop(escc_ch, "name", name, sizeof(name)) == -1)
return;
if (strcmp(name, "ch-b") == 0)
channel = 1;
if (OF_getprop(escc_ch, "reg", reg, sizeof(reg)) < 4)
return;
zs_offset = reg[0];
escc = OF_parent(escc_ch);
obio = OF_parent(escc);
if (OF_getprop(obio, "assigned-addresses", reg, sizeof(reg)) < 12)
return;
zc = (struct zschan *)(reg[2] + zs_offset);
kgdb_dev = makedev(cdevsw_lookup_major(&zstty_cdevsw), channel);
printf("zs_kgdb_init: attaching tty%02d at %d baud\n",
channel, kgdb_rate);
/* Setup temporary chanstate. */
bzero((void *)&cs, sizeof(cs));
cs.cs_channel = channel;
cs.cs_brg_clk = PCLK / 16;
cs.cs_reg_csr = &zc->zc_csr;
cs.cs_reg_data = &zc->zc_data;
/* Now set parameters. (interrupts disabled) */
zs_setparam(&cs, 0, kgdb_rate);
/* Store the getc/putc functions and arg. */
kgdb_attach(zs_getc, zs_putc, __UNVOLATILE(zc));
}
/*
* This is a "hook" called by zstty_attach to allow the tty
* to be "taken over" for exclusive use by kgdb.
* Return non-zero if this is the kgdb port.
*
* Set the speed to kgdb_rate, CS8, etc.
*/
int
zs_check_kgdb(cs, dev)
struct zs_chanstate *cs;
int dev;
{
if (dev != kgdb_dev)
return (0);
/*
* Yes, this is port in use by kgdb.
*/
cs->cs_private = NULL;
cs->cs_ops = &zsops_kgdb;
/* Now set parameters. (interrupts enabled) */
zs_setparam(cs, 1, kgdb_rate);
return (1);
}
/*
* KGDB framing character received: enter kernel debugger. This probably
* should time out after a few seconds to avoid hanging on spurious input.
*/
static void
zskgdb(cs)
struct zs_chanstate *cs;
{
int unit = minor(kgdb_dev);
printf("zstty%d: kgdb interrupt\n", unit);
/* This will trap into the debugger. */
kgdb_connect(1);
}
/****************************************************************
* Interface to the lower layer (zscc)
****************************************************************/
static void zs_kgdb_rxint __P((struct zs_chanstate *));
static void zs_kgdb_stint __P((struct zs_chanstate *, int));
static void zs_kgdb_txint __P((struct zs_chanstate *));
static void zs_kgdb_softint __P((struct zs_chanstate *));
int kgdb_input_lost;
static void
zs_kgdb_rxint(cs)
struct zs_chanstate *cs;
{
register u_char c, rr1;
/*
* First read the status, because reading the received char
* destroys the status of this char.
*/
rr1 = zs_read_reg(cs, 1);
c = zs_read_data(cs);
if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) {
/* Clear the receive error. */
zs_write_csr(cs, ZSWR0_RESET_ERRORS);
}
if (c == KGDB_START) {
zskgdb(cs);
} else {
kgdb_input_lost++;
}
}
static void
zs_kgdb_txint(cs)
register struct zs_chanstate *cs;
{
register int rr0;
rr0 = zs_read_csr(cs);
zs_write_csr(cs, ZSWR0_RESET_TXINT);
}
static void
zs_kgdb_stint(cs, force)
register struct zs_chanstate *cs;
int force;
{
register int rr0;
rr0 = zs_read_csr(cs);
zs_write_csr(cs, ZSWR0_RESET_STATUS);
/*
* Check here for console break, so that we can abort
* even when interrupts are locking up the machine.
*/
if (rr0 & ZSRR0_BREAK) {
zskgdb(cs);
}
}
static void
zs_kgdb_softint(cs)
struct zs_chanstate *cs;
{
printf("zs_kgdb_softint?\n");
}
struct zsops zsops_kgdb = {
zs_kgdb_rxint, /* receive char available */
zs_kgdb_stint, /* external/status */
zs_kgdb_txint, /* xmit buffer empty */
zs_kgdb_softint, /* process software interrupt */
};