xref: /netbsd-src/sys/arch/sparc/dev/zs_kgdb.c (revision 481fca6e59249d8ffcf24fef7cfbe7b131bfb080)
1 /*	$NetBSD: zs_kgdb.c,v 1.5 2000/03/21 12:48:45 pk 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 <sys/param.h>
51 #include <sys/systm.h>
52 #include <sys/proc.h>
53 #include <sys/device.h>
54 #include <sys/conf.h>
55 #include <sys/ioctl.h>
56 #include <sys/kernel.h>
57 #include <sys/syslog.h>
58 #include <sys/kgdb.h>
59 
60 #include <dev/ic/z8530reg.h>
61 #include <machine/z8530var.h>
62 #include <machine/promlib.h>
63 #include <sparc/dev/cons.h>
64 
65 /* Suns provide a 4.9152 MHz clock to the ZS chips. */
66 #define PCLK	(9600 * 512)	/* PCLK pin input clock rate */
67 
68 /* The layout of this is hardware-dependent (padding, order). */
69 struct zschan {
70 	volatile u_char	zc_csr;		/* ctrl,status, and indirect access */
71 	u_char		zc_xxx0;
72 	volatile u_char	zc_data;	/* data */
73 	u_char		zc_xxx1;
74 };
75 struct zsdevice {
76 	/* Yes, they are backwards. */
77 	struct	zschan zs_chan_b;
78 	struct	zschan zs_chan_a;
79 };
80 
81 static void zs_setparam __P((struct zs_chanstate *, int, int));
82 static void *findzs __P((int));
83 struct zsops zsops_kgdb;
84 
85 extern int  zs_getc __P((void *arg));
86 extern void zs_putc __P((void *arg, int c));
87 
88 static u_char zs_kgdb_regs[16] = {
89 	0,	/* 0: CMD (reset, etc.) */
90 	0,	/* 1: No interrupts yet. */
91 	0,	/* 2: IVECT */
92 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
93 	ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
94 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
95 	0,	/* 6: TXSYNC/SYNCLO */
96 	0,	/* 7: RXSYNC/SYNCHI */
97 	0,	/* 8: alias for data port */
98 	ZSWR9_MASTER_IE | ZSWR9_NO_VECTOR,
99 	0,	/*10: Misc. TX/RX control bits */
100 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
101 	14,	/*12: BAUDLO (default=9600) */
102 	0,	/*13: BAUDHI (default=9600) */
103 	ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
104 	ZSWR15_BREAK_IE,
105 };
106 
107 /*
108  * This replaces "zs_reset()" in the sparc driver.
109  */
110 static void
111 zs_setparam(cs, iena, rate)
112 	struct zs_chanstate *cs;
113 	int iena;
114 	int rate;
115 {
116 	int s, tconst;
117 
118 	bcopy(zs_kgdb_regs, cs->cs_preg, 16);
119 
120 	if (iena) {
121 		cs->cs_preg[1] = ZSWR1_RIE | ZSWR1_SIE;
122 	}
123 
124 	/* Initialize the speed, etc. */
125 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, rate);
126 	cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS;
127 	cs->cs_preg[12] = tconst;
128 	cs->cs_preg[13] = tconst >> 8;
129 
130 	s = splhigh();
131 	zs_loadchannelregs(cs);
132 	splx(s);
133 }
134 
135 /*
136  * Set up for kgdb; called at boot time before configuration.
137  * KGDB interrupts will be enabled later when zs0 is configured.
138  * Called after cninit(), so printf() etc. works.
139  */
140 void
141 zs_kgdb_init()
142 {
143 	struct zs_chanstate cs;
144 	struct zsdevice *zsd;
145 	volatile struct zschan *zc;
146 	int channel, promzs_unit;
147 
148 	/* printf("zs_kgdb_init: kgdb_dev=0x%x\n", kgdb_dev); */
149 	if (major(kgdb_dev) != zs_major)
150 		return;
151 
152 	/* Note: (ttya,ttyb) on zs0, and (ttyc,ttyd) on zs2 */
153 	promzs_unit = (kgdb_dev & 2) ? 2 : 0;
154 	channel  =  kgdb_dev & 1;
155 	printf("zs_kgdb_init: attaching tty%c at %d baud\n",
156 		   'a' + (kgdb_dev & 3), kgdb_rate);
157 
158 	/* Setup temporary chanstate. */
159 	bzero((caddr_t)&cs, sizeof(cs));
160 	zsd = findzs(promzs_unit);
161 	if (zsd == NULL) {
162 		printf("zs_kgdb_init: zs not mapped.\n");
163 		return;
164 	}
165 	zc = (channel == 0) ? &zsd->zs_chan_a : &zsd->zs_chan_b;
166 
167 	cs.cs_channel = channel;
168 	cs.cs_brg_clk = PCLK / 16;
169 	cs.cs_reg_csr  = &zc->zc_csr;
170 	cs.cs_reg_data = &zc->zc_data;
171 
172 	/* Now set parameters. (interrupts disabled) */
173 	zs_setparam(&cs, 0, kgdb_rate);
174 
175 	/* Store the getc/putc functions and arg. */
176 	kgdb_attach(zs_getc, zs_putc, (void *)zc);
177 }
178 
179 /*
180  * This is a "hook" called by zstty_attach to allow the tty
181  * to be "taken over" for exclusive use by kgdb.
182  * Return non-zero if this is the kgdb port.
183  *
184  * Set the speed to kgdb_rate, CS8, etc.
185  */
186 int
187 zs_check_kgdb(cs, dev)
188 	struct zs_chanstate *cs;
189 	int dev;
190 {
191 
192 	if (dev != kgdb_dev)
193 		return (0);
194 
195 	/*
196 	 * Yes, this is port in use by kgdb.
197 	 */
198 	cs->cs_private = NULL;
199 	cs->cs_ops = &zsops_kgdb;
200 
201 	/* Now set parameters. (interrupts enabled) */
202 	zs_setparam(cs, 1, kgdb_rate);
203 
204 	return (1);
205 }
206 
207 /*
208  * KGDB framing character received: enter kernel debugger.  This probably
209  * should time out after a few seconds to avoid hanging on spurious input.
210  */
211 void
212 zskgdb(cs)
213 	struct zs_chanstate *cs;
214 {
215 	int unit = minor(kgdb_dev);
216 
217 	printf("zstty%d: kgdb interrupt\n", unit);
218 	/* This will trap into the debugger. */
219 	kgdb_connect(1);
220 }
221 
222 
223 /****************************************************************
224  * Interface to the lower layer (zscc)
225  ****************************************************************/
226 
227 static void zs_kgdb_rxint __P((struct zs_chanstate *));
228 static void zs_kgdb_stint __P((struct zs_chanstate *, int));
229 static void zs_kgdb_txint __P((struct zs_chanstate *));
230 static void zs_kgdb_softint __P((struct zs_chanstate *));
231 
232 int kgdb_input_lost;
233 
234 static void
235 zs_kgdb_rxint(cs)
236 	struct zs_chanstate *cs;
237 {
238 	register u_char c, rr1;
239 
240 	/*
241 	 * First read the status, because reading the received char
242 	 * destroys the status of this char.
243 	 */
244 	rr1 = zs_read_reg(cs, 1);
245 	c = zs_read_data(cs);
246 
247 	if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) {
248 		/* Clear the receive error. */
249 		zs_write_csr(cs, ZSWR0_RESET_ERRORS);
250 	}
251 
252 	if (c == KGDB_START) {
253 		zskgdb(cs);
254 	} else {
255 		kgdb_input_lost++;
256 	}
257 }
258 
259 static void
260 zs_kgdb_txint(cs)
261 	register struct zs_chanstate *cs;
262 {
263 	register int rr0;
264 
265 	rr0 = zs_read_csr(cs);
266 	zs_write_csr(cs, ZSWR0_RESET_TXINT);
267 }
268 
269 static void
270 zs_kgdb_stint(cs, force)
271 	register struct zs_chanstate *cs;
272 	int force;
273 {
274 	register int rr0;
275 
276 	rr0 = zs_read_csr(cs);
277 	zs_write_csr(cs, ZSWR0_RESET_STATUS);
278 
279 	/*
280 	 * Check here for console break, so that we can abort
281 	 * even when interrupts are locking up the machine.
282 	 */
283 	if (rr0 & ZSRR0_BREAK) {
284 		zskgdb(cs);
285 	}
286 }
287 
288 static void
289 zs_kgdb_softint(cs)
290 	struct zs_chanstate *cs;
291 {
292 	printf("zs_kgdb_softint?\n");
293 }
294 
295 struct zsops zsops_kgdb = {
296 	zs_kgdb_rxint,	/* receive char available */
297 	zs_kgdb_stint,	/* external/status */
298 	zs_kgdb_txint,	/* xmit buffer empty */
299 	zs_kgdb_softint,	/* process software interrupt */
300 };
301 
302 /*
303  * findzs() should return the address of the given zs channel.
304  * Here we count on the PROM to map in the required zs chips.
305  */
306 void *
307 findzs(zs)
308 	int zs;
309 {
310 
311 #if defined(SUN4)
312 	if (CPU_ISSUN4) {
313 		/*
314 		 * On sun4, we use hard-coded physical addresses
315 		 */
316 #define ZS0_PHYS	0xf1000000
317 #define ZS1_PHYS	0xf0000000
318 #define ZS2_PHYS	0xe0000000
319 		bus_space_handle_t bh;
320 		bus_addr_t paddr;
321 
322 		switch (zs) {
323 		case 0:
324 			paddr = ZS0_PHYS;
325 			break;
326 		case 1:
327 			paddr = ZS1_PHYS;
328 			break;
329 		case 2:
330 			paddr = ZS2_PHYS;
331 			break;
332 		default:
333 			return (NULL);
334 		}
335 
336 		if (cpuinfo.cpu_type == CPUTYP_4_100)
337 			/* Clear top bits of physical address on 4/100 */
338 			paddr &= ~0xf0000000;
339 
340 		/*
341 		 * Have the obio module figure out which virtual
342 		 * address the device is mapped to.
343 		 */
344 		if (obio_find_rom_map(paddr, PMAP_OBIO, NBPG, &bh) != 0)
345 			return (NULL);
346 
347 		return ((void *)bh);
348 	}
349 #endif
350 
351 #if defined(SUN4C) || defined(SUN4M)
352 	if (CPU_ISSUN4COR4M) {
353 		int node;
354 
355 		node = firstchild(findroot());
356 		if (CPU_ISSUN4M) {
357 			/*
358 			 * On sun4m machines zs is in "obio" tree.
359 			 */
360 			node = findnode(node, "obio");
361 			if (node == 0)
362 				panic("findzs: no obio node");
363 			node = firstchild(node);
364 		}
365 		while ((node = findnode(node, "zs")) != 0) {
366 			int nvaddrs, *vaddrs, vstore[10];
367 
368 			if (getpropint(node, "slave", -1) != zs) {
369 				node = nextsibling(node);
370 				continue;
371 			}
372 
373 			/*
374 			 * On some machines (e.g. the Voyager), the zs
375 			 * device has multi-valued register properties.
376 			 */
377 			vaddrs = vstore;
378 			nvaddrs = sizeof(vstore)/sizeof(vstore[0]);
379 			if (getprop(node, "address", sizeof(int),
380 				    &nvaddrs, (void **)&vaddrs) != 0)
381 				return (NULL);
382 
383 			return ((void *)vaddrs[0]);
384 		}
385 	}
386 #endif
387 	return (NULL);
388 }
389