xref: /netbsd-src/sys/arch/sparc/dev/zs_kgdb.c (revision d710132b4b8ce7f7cccaaf660cb16aa16b4077a0)
1 /*	$NetBSD: zs_kgdb.c,v 1.11 2003/04/02 04:35:28 thorpej Exp $	*/
2 
3 /*-
4  * Copyright (c) 1996 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Gordon W. Ross.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Hooks for kgdb when attached via the z8530 driver
41  *
42  * To use this, build a kernel with: option KGDB, and
43  * boot that kernel with "-d".  (The kernel will call
44  * zs_kgdb_init, kgdb_connect.)  When the console prints
45  * "kgdb waiting..." you run "gdb -k kernel" and do:
46  *   (gdb) set remotebaud 19200
47  *   (gdb) target remote /dev/ttyb
48  */
49 
50 #include "opt_kgdb.h"
51 
52 #include <sys/param.h>
53 #include <sys/systm.h>
54 #include <sys/proc.h>
55 #include <sys/device.h>
56 #include <sys/conf.h>
57 #include <sys/ioctl.h>
58 #include <sys/kernel.h>
59 #include <sys/syslog.h>
60 #include <sys/kgdb.h>
61 
62 #include <dev/ic/z8530reg.h>
63 #include <machine/z8530var.h>
64 #include <machine/autoconf.h>
65 #include <machine/promlib.h>
66 #include <sparc/dev/cons.h>
67 
68 /* Suns provide a 4.9152 MHz clock to the ZS chips. */
69 #define PCLK	(9600 * 512)	/* PCLK pin input clock rate */
70 
71 /* The layout of this is hardware-dependent (padding, order). */
72 struct zschan {
73 	volatile u_char	zc_csr;		/* ctrl,status, and indirect access */
74 	u_char		zc_xxx0;
75 	volatile u_char	zc_data;	/* data */
76 	u_char		zc_xxx1;
77 };
78 struct zsdevice {
79 	/* Yes, they are backwards. */
80 	struct	zschan zs_chan_b;
81 	struct	zschan zs_chan_a;
82 };
83 
84 static void zs_setparam __P((struct zs_chanstate *, int, int));
85 static void *findzs __P((int));
86 struct zsops zsops_kgdb;
87 
88 extern int  zs_getc __P((void *arg));
89 extern void zs_putc __P((void *arg, int c));
90 
91 static u_char zs_kgdb_regs[16] = {
92 	0,	/* 0: CMD (reset, etc.) */
93 	0,	/* 1: No interrupts yet. */
94 	0,	/* 2: IVECT */
95 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
96 	ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
97 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
98 	0,	/* 6: TXSYNC/SYNCLO */
99 	0,	/* 7: RXSYNC/SYNCHI */
100 	0,	/* 8: alias for data port */
101 	ZSWR9_MASTER_IE | ZSWR9_NO_VECTOR,
102 	0,	/*10: Misc. TX/RX control bits */
103 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
104 	14,	/*12: BAUDLO (default=9600) */
105 	0,	/*13: BAUDHI (default=9600) */
106 	ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
107 	ZSWR15_BREAK_IE,
108 };
109 
110 /*
111  * This replaces "zs_reset()" in the sparc driver.
112  */
113 static void
114 zs_setparam(cs, iena, rate)
115 	struct zs_chanstate *cs;
116 	int iena;
117 	int rate;
118 {
119 	int s, tconst;
120 
121 	bcopy(zs_kgdb_regs, cs->cs_preg, 16);
122 
123 	if (iena) {
124 		cs->cs_preg[1] = ZSWR1_RIE | ZSWR1_SIE;
125 	}
126 
127 	/* Initialize the speed, etc. */
128 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, rate);
129 	cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS;
130 	cs->cs_preg[12] = tconst;
131 	cs->cs_preg[13] = tconst >> 8;
132 
133 	s = splhigh();
134 	zs_loadchannelregs(cs);
135 	splx(s);
136 }
137 
138 /*
139  * Set up for kgdb; called at boot time before configuration.
140  * KGDB interrupts will be enabled later when zs0 is configured.
141  * Called after cninit(), so printf() etc. works.
142  */
143 void
144 zs_kgdb_init()
145 {
146 	struct zs_chanstate cs;
147 	struct zsdevice *zsd;
148 	volatile struct zschan *zc;
149 	int channel, promzs_unit;
150 	extern const struct cdevsw zstty_cdevsw;
151 
152 	/* printf("zs_kgdb_init: kgdb_dev=0x%x\n", kgdb_dev); */
153 	if (cdevsw_lookup(kgdb_dev) != &zstty_cdevsw)
154 		return;
155 
156 	/* Note: (ttya,ttyb) on zs0, and (ttyc,ttyd) on zs2 */
157 	promzs_unit = (kgdb_dev & 2) ? 2 : 0;
158 	channel  =  kgdb_dev & 1;
159 	printf("zs_kgdb_init: attaching tty%c at %d baud\n",
160 		   'a' + (kgdb_dev & 3), kgdb_rate);
161 
162 	/* Setup temporary chanstate. */
163 	bzero((caddr_t)&cs, sizeof(cs));
164 	zsd = findzs(promzs_unit);
165 	if (zsd == NULL) {
166 		printf("zs_kgdb_init: zs not mapped.\n");
167 		return;
168 	}
169 	zc = (channel == 0) ? &zsd->zs_chan_a : &zsd->zs_chan_b;
170 
171 	cs.cs_channel = channel;
172 	cs.cs_brg_clk = PCLK / 16;
173 	cs.cs_reg_csr  = &zc->zc_csr;
174 	cs.cs_reg_data = &zc->zc_data;
175 
176 	/* Now set parameters. (interrupts disabled) */
177 	zs_setparam(&cs, 0, kgdb_rate);
178 
179 	/* Store the getc/putc functions and arg. */
180 	kgdb_attach(zs_getc, zs_putc, (void *)zc);
181 }
182 
183 /*
184  * This is a "hook" called by zstty_attach to allow the tty
185  * to be "taken over" for exclusive use by kgdb.
186  * Return non-zero if this is the kgdb port.
187  *
188  * Set the speed to kgdb_rate, CS8, etc.
189  */
190 int
191 zs_check_kgdb(cs, dev)
192 	struct zs_chanstate *cs;
193 	int dev;
194 {
195 
196 	if (dev != kgdb_dev)
197 		return (0);
198 
199 	/*
200 	 * Yes, this is port in use by kgdb.
201 	 */
202 	cs->cs_private = NULL;
203 	cs->cs_ops = &zsops_kgdb;
204 
205 	/* Now set parameters. (interrupts enabled) */
206 	zs_setparam(cs, 1, kgdb_rate);
207 
208 	return (1);
209 }
210 
211 /*
212  * KGDB framing character received: enter kernel debugger.  This probably
213  * should time out after a few seconds to avoid hanging on spurious input.
214  */
215 void
216 zskgdb(cs)
217 	struct zs_chanstate *cs;
218 {
219 	int unit = minor(kgdb_dev);
220 
221 	printf("zstty%d: kgdb interrupt\n", unit);
222 	/* This will trap into the debugger. */
223 	kgdb_connect(1);
224 }
225 
226 
227 /****************************************************************
228  * Interface to the lower layer (zscc)
229  ****************************************************************/
230 
231 static void zs_kgdb_rxint __P((struct zs_chanstate *));
232 static void zs_kgdb_stint __P((struct zs_chanstate *, int));
233 static void zs_kgdb_txint __P((struct zs_chanstate *));
234 static void zs_kgdb_softint __P((struct zs_chanstate *));
235 
236 int kgdb_input_lost;
237 
238 static void
239 zs_kgdb_rxint(cs)
240 	struct zs_chanstate *cs;
241 {
242 	register u_char c, rr1;
243 
244 	/*
245 	 * First read the status, because reading the received char
246 	 * destroys the status of this char.
247 	 */
248 	rr1 = zs_read_reg(cs, 1);
249 	c = zs_read_data(cs);
250 
251 	if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) {
252 		/* Clear the receive error. */
253 		zs_write_csr(cs, ZSWR0_RESET_ERRORS);
254 	}
255 
256 	if (c == KGDB_START) {
257 		zskgdb(cs);
258 	} else {
259 		kgdb_input_lost++;
260 	}
261 }
262 
263 static void
264 zs_kgdb_txint(cs)
265 	register struct zs_chanstate *cs;
266 {
267 	register int rr0;
268 
269 	rr0 = zs_read_csr(cs);
270 	zs_write_csr(cs, ZSWR0_RESET_TXINT);
271 }
272 
273 static void
274 zs_kgdb_stint(cs, force)
275 	register struct zs_chanstate *cs;
276 	int force;
277 {
278 	register int rr0;
279 
280 	rr0 = zs_read_csr(cs);
281 	zs_write_csr(cs, ZSWR0_RESET_STATUS);
282 
283 	/*
284 	 * Check here for console break, so that we can abort
285 	 * even when interrupts are locking up the machine.
286 	 */
287 	if (rr0 & ZSRR0_BREAK) {
288 		zskgdb(cs);
289 	}
290 }
291 
292 static void
293 zs_kgdb_softint(cs)
294 	struct zs_chanstate *cs;
295 {
296 	printf("zs_kgdb_softint?\n");
297 }
298 
299 struct zsops zsops_kgdb = {
300 	zs_kgdb_rxint,	/* receive char available */
301 	zs_kgdb_stint,	/* external/status */
302 	zs_kgdb_txint,	/* xmit buffer empty */
303 	zs_kgdb_softint,	/* process software interrupt */
304 };
305 
306 /*
307  * findzs() should return the address of the given zs channel.
308  * Here we count on the PROM to map in the required zs chips.
309  */
310 void *
311 findzs(zs)
312 	int zs;
313 {
314 
315 #if defined(SUN4)
316 	if (CPU_ISSUN4) {
317 		/*
318 		 * On sun4, we use hard-coded physical addresses
319 		 */
320 #define ZS0_PHYS	0xf1000000
321 #define ZS1_PHYS	0xf0000000
322 #define ZS2_PHYS	0xe0000000
323 		bus_space_handle_t bh;
324 		bus_addr_t paddr;
325 
326 		switch (zs) {
327 		case 0:
328 			paddr = ZS0_PHYS;
329 			break;
330 		case 1:
331 			paddr = ZS1_PHYS;
332 			break;
333 		case 2:
334 			paddr = ZS2_PHYS;
335 			break;
336 		default:
337 			return (NULL);
338 		}
339 
340 		if (cpuinfo.cpu_type == CPUTYP_4_100)
341 			/* Clear top bits of physical address on 4/100 */
342 			paddr &= ~0xf0000000;
343 
344 		/*
345 		 * Have the obio module figure out which virtual
346 		 * address the device is mapped to.
347 		 */
348 		if (obio_find_rom_map(paddr, PMAP_OBIO, PAGE_SIZE, &bh) != 0)
349 			return (NULL);
350 
351 		return ((void *)bh);
352 	}
353 #endif
354 
355 #if defined(SUN4C) || defined(SUN4M)
356 	if (CPU_ISSUN4C || CPU_ISSUN4M) {
357 		int node;
358 
359 		node = firstchild(findroot());
360 		if (CPU_ISSUN4M) {
361 			/*
362 			 * On sun4m machines zs is in "obio" tree.
363 			 */
364 			node = findnode(node, "obio");
365 			if (node == 0)
366 				panic("findzs: no obio node");
367 			node = firstchild(node);
368 		}
369 		while ((node = findnode(node, "zs")) != 0) {
370 			int nvaddrs, *vaddrs, vstore[10];
371 
372 			if (PROM_getpropint(node, "slave", -1) != zs) {
373 				node = nextsibling(node);
374 				continue;
375 			}
376 
377 			/*
378 			 * On some machines (e.g. the Voyager), the zs
379 			 * device has multi-valued register properties.
380 			 */
381 			vaddrs = vstore;
382 			nvaddrs = sizeof(vstore)/sizeof(vstore[0]);
383 			if (PROM_getprop(node, "address", sizeof(int),
384 				    &nvaddrs, (void **)&vaddrs) != 0)
385 				return (NULL);
386 
387 			return ((void *)vaddrs[0]);
388 		}
389 	}
390 #endif
391 	return (NULL);
392 }
393