xref: /netbsd-src/sys/arch/rs6000/mca/mca_machdep.c (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /*	$NetBSD: mca_machdep.c,v 1.5 2020/11/21 15:52:32 thorpej Exp $	*/
2 
3 /*-
4  * Copyright (c) 2000, 2001 The NetBSD Foundation, Inc.
5  * Copyright (c) 1996-1999 Scott D. Telford.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Scott Telford <s.telford@ed.ac.uk> and Jaromir Dolecek
10  * <jdolecek@NetBSD.org>.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
23  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
25  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 /*
35  * Machine-specific functions for MCA autoconfiguration.
36  */
37 
38 #include <sys/cdefs.h>
39 __KERNEL_RCSID(0, "$NetBSD: mca_machdep.c,v 1.5 2020/11/21 15:52:32 thorpej Exp $");
40 
41 #include <sys/types.h>
42 #include <sys/param.h>
43 #include <sys/device.h>
44 #include <sys/kmem.h>
45 #include <sys/systm.h>
46 #include <sys/syslog.h>
47 #include <sys/time.h>
48 #include <sys/kernel.h>
49 
50 #include <powerpc/pio.h>
51 #define _POWERPC_BUS_DMA_PRIVATE
52 #include <sys/bus.h>
53 
54 #include <dev/mca/mcavar.h>
55 #include <dev/mca/mcareg.h>
56 
57 #include "opt_mcaverbose.h"
58 
59 #ifdef UNUSED
60 static void	_mca_bus_dmamap_sync(bus_dma_tag_t, bus_dmamap_t,
61 		    bus_addr_t, bus_size_t, int);
62 #endif
63 
64 /*
65  * For now, we use MCA DMA to 0-16M always. Some IBM PS/2 have 32bit MCA bus,
66  * but majority of them have 24bit only.
67  */
68 #define	MCA_DMA_BOUNCE_THRESHOLD	(16 * 1024 * 1024)
69 
70 /* Updated in mca_busprobe() if appropriate. */
71 int MCA_system = 0;
72 
73 //static bus_space_handle_t dmaiot, dmacmdh, dmaexech;
74 
75 #define MAX_SLAVE_CHANNELS	8
76 #define MAX_DMA_CHANNELS	16
77 
78 #define INIT_DMA_CHN_BITMASK()	(0xFFFFFFFF << (32 - MAX_DMA_CHANS))
79 #define INIT_SLAVE_CHN_BITMASK(slaves)	(0xFFFFFFFF << (32 - (slaves))
80 
81 #define DMA_AVAIL(chn, bitmask)	((bitmask) & (1 << (31 - (chn))))
82 #define DMA_ALLOC(chn, bitmask) ((bitmask) &= ~(1 << (31 - (chn))))
83 #define DMA_FREE(chn, bitmask)	((bitmask) |= (1 << (31 - (chn))))
84 
85 /*
86  * MCA DMA controller commands. The exact sense of individual bits
87  * are from Tymm Twillman <tymm@computer.org>, who worked on Linux MCA DMA
88  * support.
89  */
90 #define DMACMD_SET_IO		0x00	/* set port (16bit) for i/o transfer */
91 #define DMACMD_SET_ADDR		0x20	/* set addr (24bit) for i/o transfer */
92 #define DMACMD_GET_ADDR		0x30	/* get addr (24bit) for i/o transfer */
93 #define	DMACMD_SET_CNT		0x40	/* set memory size for DMA (16b) */
94 #define DMACMD_GET_CNT		0x50	/* get count of remaining bytes in DMA*/
95 #define DMACMD_GET_STATUS	0x60	/* ?? */
96 #define DMACMD_SET_MODE		0x70	/* set DMA mode */
97 # define DMACMD_MODE_XFER	0x04	/* do transfer, read by default */
98 # define DMACMD_MODE_READ	0x08	/* read transfer */
99 # define DMACMD_MODE_WRITE	0x00	/* write transfer */
100 # define DMACMD_MODE_IOPORT	0x01	/* DMA from/to IO register */
101 # define DMACMD_MODE_16BIT	0x40	/* 16bit transfers (default 8bit) */
102 #define DMACMD_SET_ARBUS	0x80	/* ?? */
103 #define DMACMD_MASK		0x90	/* command mask */
104 #define DMACMD_RESET_MASK	0xA0	/* reset */
105 #define DMACMD_MASTER_CLEAR	0xD0	/* ?? */
106 
107 const struct evcnt *
108 mca_intr_evcnt(mca_chipset_tag_t ic, int irq)
109 {
110 	/* XXX for now, no evcnt parent reported */
111 	return NULL;
112 }
113 
114 /*
115  * Map the MCA DMA controller registers.
116  */
117 void
118 mca_attach_hook(device_t parent, device_t self, struct mcabus_attach_args *mba)
119 {
120 #if 0
121 	dmaiot = mba->mba_iot;
122 
123 	if (bus_space_map(dmaiot, DMA_CMD, 1, 0, &dmacmdh)
124 	    || bus_space_map(dmaiot, DMA_EXEC, 1, 0, &dmaexech))
125 		panic("mca: couldn't map DMA registers");
126 #endif
127 }
128 
129 /*
130  * Read value of MCA POS register "reg" in slot "slot".
131  */
132 
133 int
134 mca_conf_read(mca_chipset_tag_t mc, int slot, int reg)
135 {
136 	int	data;
137 
138 	slot &= 15;	/* slot must be in range 0-15 */
139 	data = inb(RS6000_BUS_SPACE_IO + MCA_POS_REG(reg) + (slot<<16));
140 	return data;
141 }
142 
143 
144 /*
145  * Write "data" to MCA POS register "reg" in slot "slot".
146  */
147 
148 void
149 mca_conf_write(mca_chipset_tag_t mc, int slot, int reg, int data)
150 {
151 	slot &= 15;	/* slot must be in range 0-15 */
152 	outb(RS6000_BUS_SPACE_IO + MCA_POS_REG(reg) + (slot<<16), data);
153 }
154 
155 
156 void *
157 mca_intr_establish(mca_chipset_tag_t mc, mca_intr_handle_t ih,
158     int level, int (*func)(void *), void *arg)
159 {
160 	if (ih == 0 || ih >= ICU_LEN)
161 		panic("mca_intr_establish: bogus handle 0x%x", ih);
162 
163 	/* MCA interrupts are always level-triggered */
164 	return intr_establish(ih, IST_LEVEL, level, func, arg);
165 }
166 
167 void
168 mca_intr_disestablish(mca_chipset_tag_t mc, void *cookie)
169 {
170 	intr_disestablish(cookie);
171 }
172 
173 
174 /*
175  * Handle a NMI.
176  * return true to panic system, false to ignore.
177  */
178 int
179 mca_nmi(void)
180 {
181 	/*
182 	* PS/2 MCA devices can generate NMIs - we can find out which
183 	* slot generated it from the POS registers.
184 	*/
185 
186 	int 	slot, mcanmi=0;
187 
188 	/* if there is no MCA bus, call x86_nmi() */
189 	if (!MCA_system)
190 		goto out;
191 
192 	/* ensure motherboard setup is disabled */
193 	outb(MCA_MB_SETUP_REG, 0xff);
194 
195 	/* find if an MCA slot has the CHCK bit asserted (low) in POS 5 */
196 	for(slot=0; slot<MCA_MAX_SLOTS; slot++) {
197 		outb(MCA_ADAP_SETUP_REG, slot | MCA_ADAP_SET);
198 		if ((inb(MCA_POS_REG(5)) & MCA_POS5_CHCK) == 0) {
199 			mcanmi = 1;
200 			/* find if CHCK status is available in POS 6/7 */
201 			if((inb(MCA_POS_REG(5)) & MCA_POS5_CHCK_STAT) == 0)
202 				log(LOG_CRIT, "MCA NMI: slot %d, POS6=0x%02x, POS7=0x%02x\n",
203 					slot+1, inb(MCA_POS_REG(6)),
204 						inb(MCA_POS_REG(7)));
205 			else
206 				log(LOG_CRIT, "MCA NMI: slot %d\n", slot+1);
207 		}
208 	}
209 	outb(MCA_ADAP_SETUP_REG, 0);
210 
211    out:
212 	if (!mcanmi) {
213 		/* no CHCK bits asserted, assume ISA NMI */
214 		//return (x86_nmi());
215 		return 0;
216 	} else
217 		return(0);
218 }
219 
220 /*
221  * Realistically, we should probe for the presence of an MCA bus here, and
222  * return a reasonable value.  However, this port is never expected to run
223  * on anything other than MCA, so rather than write a bunch of complex code
224  * to find that we indeed have a bus, lets just assume we do.
225  */
226 void
227 mca_busprobe(void)
228 {
229 	MCA_system = 1;
230 }
231 
232 #define PORT_DISKLED	0x92
233 #define DISKLED_ON	0x40
234 
235 /*
236  * Light disk busy LED on IBM PS/2.
237  */
238 void
239 mca_disk_busy(void)
240 {
241 	outb(PORT_DISKLED, inb(PORT_DISKLED) | DISKLED_ON);
242 }
243 
244 /*
245  * Turn off disk LED on IBM PS/2.
246  */
247 void
248 mca_disk_unbusy(void)
249 {
250 	outb(PORT_DISKLED, inb(PORT_DISKLED) & ~DISKLED_ON);
251 }
252 
253 /*
254  * -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
255  * MCA DMA specific stuff. We use ISA routines for bulk of the work,
256  * since MCA shares much of the charasteristics with it. We just hook
257  * the DMA channel initialization and kick MCA DMA controller appropriately.
258  * -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
259  */
260 
261 #ifdef NOTYET
262 /*
263  * Synchronize a MCA DMA map.
264  */
265 static void
266 _mca_bus_dmamap_sync(bus_dma_tag_t t, bus_dmamap_t map, bus_addr_t offset,
267     bus_size_t len, int ops)
268 {
269 	struct rs6000_dma_cookie *cookie;
270 	bus_addr_t phys;
271 	bus_size_t cnt;
272 	int dmach, mode;
273 
274 	_bus_dmamap_sync(t, map, offset, len, ops);
275 
276 	/*
277 	 * Don't do anything if not using the DMA controller.
278 	 */
279 	if ((map->_dm_flags & _MCABUS_DMA_USEDMACTRL) == 0)
280 		return;
281 
282 	/*
283 	 * Don't do anything if not PRE* operation, allow only
284 	 * one of PREREAD and PREWRITE.
285 	 */
286 	if (ops != BUS_DMASYNC_PREREAD && ops != BUS_DMASYNC_PREWRITE)
287 		return;
288 
289 	cookie = (struct rs6000_dma_cookie *)map->_dm_cookie;
290 	dmach = (cookie->id_flags & 0xf0) >> 4;
291 
292 	phys = map->dm_segs[0].ds_addr;
293 	cnt = map->dm_segs[0].ds_len;
294 
295 	mode = DMACMD_MODE_XFER;
296 	mode |= (ops == BUS_DMASYNC_PREREAD)
297 			? DMACMD_MODE_READ : DMACMD_MODE_WRITE;
298 	if (map->_dm_flags & MCABUS_DMA_IOPORT)
299 		mode |= DMACMD_MODE_IOPORT;
300 
301 	/* Use 16bit DMA if requested */
302 	if (map->_dm_flags & MCABUS_DMA_16BIT) {
303 #ifdef DIAGNOSTIC
304 		if ((cnt % 2) != 0) {
305 			panic("_mca_bus_dmamap_sync: 16bit DMA and cnt %lu odd",
306 				cnt);
307 		}
308 #endif
309 		mode |= DMACMD_MODE_16BIT;
310 		cnt /= 2;
311 	}
312 
313 	/*
314 	 * Initialize the MCA DMA controller appropriately. The exact
315 	 * sequence to setup the controller is taken from Minix.
316 	 */
317 
318 	/* Disable access to DMA channel. */
319 	bus_space_write_1(dmaiot, dmacmdh, 0, DMACMD_MASK | dmach);
320 
321 	/* Set the transfer mode. */
322 	bus_space_write_1(dmaiot, dmacmdh, 0, DMACMD_SET_MODE | dmach);
323 	bus_space_write_1(dmaiot, dmaexech, 0, mode);
324 
325 	/* Set the address byte pointer. */
326 	bus_space_write_1(dmaiot, dmacmdh, 0, DMACMD_SET_ADDR | dmach);
327 	/* address bits 0..7   */
328 	bus_space_write_1(dmaiot, dmaexech, 0, (phys >> 0) & 0xff);
329 	/* address bits 8..15  */
330 	bus_space_write_1(dmaiot, dmaexech, 0, (phys >> 8) & 0xff);
331 	/* address bits 16..23  */
332 	bus_space_write_1(dmaiot, dmaexech, 0, (phys >> 16) & 0xff);
333 
334 	/* Set the count byte pointer */
335 	bus_space_write_1(dmaiot, dmacmdh, 0, DMACMD_SET_CNT | dmach);
336 	/* count bits 0..7     */
337 	bus_space_write_1(dmaiot, dmaexech, 0, ((cnt - 1) >> 0) & 0xff);
338 	/* count bits 8..15    */
339 	bus_space_write_1(dmaiot, dmaexech, 0, ((cnt - 1) >> 8) & 0xff);
340 
341 	/* Enable access to DMA channel. */
342 	bus_space_write_1(dmaiot, dmacmdh, 0, DMACMD_RESET_MASK | dmach);
343 }
344 #endif
345 
346 /*
347  * Allocate a DMA map, and set up DMA channel.
348  */
349 int
350 mca_dmamap_create(bus_dma_tag_t t, bus_size_t size, int flags,
351     bus_dmamap_t *dmamp, int dmach)
352 {
353 #if 0
354 	int error;
355 	struct rs6000_dma_cookie *cookie;
356 
357 #ifdef DEBUG
358 	/* Sanity check */
359 	if (dmach < 0 || dmach >= MAX_DMA_CHANNELS) {
360 		printf("mcadma_create: invalid DMA channel %d\n",
361 			dmach);
362 		return (EINVAL);
363 	}
364 
365 	if (size > 65536) {
366 		panic("mca_dmamap_create: dmamap sz %ld > 65536",
367 		    (long) size);
368 	}
369 #endif
370 
371 	/*
372 	 * MCA DMA transfer can be maximum 65536 bytes long and must
373 	 * be in one chunk. No specific boundary constraints are present.
374 	 */
375 	if ((error = _bus_dmamap_create(t, size, 1, 65536, 0, flags, dmamp)))
376 		return (error);
377 
378 	cookie = (struct rs6000_dma_cookie *) (*dmamp)->_dm_cookie;
379 
380 	if (cookie == NULL) {
381 		/*
382 		 * Allocate our cookie if not yet done.
383 		 */
384 		cookie = kmem_zalloc(sizeof(struct rs6000_dma_cookie),
385 		    ((flags & BUS_DMA_NOWAIT) ? KM_SLEEP : KM_NOSLEEP));
386 		if (cookie == NULL) {
387 
388 			return ENOMEM;
389 		}
390 		(*dmamp)->_dm_cookie = cookie;
391 	}
392 
393 
394 	/* Encode DMA channel */
395 	cookie->id_flags &= 0x0f;
396 	cookie->id_flags |= dmach << 4;
397 
398 	/* Mark the dmamap as using DMA controller. Some devices
399 	 * drive DMA themselves, and don't need the MCA DMA controller.
400 	 * To distinguish the two, use a flag for dmamaps which use the DMA
401 	 * controller.
402  	 */
403 	(*dmamp)->_dm_flags |= _MCABUS_DMA_USEDMACTRL;
404 #endif
405 	return (0);
406 }
407 
408 /*
409  * Set I/O port for DMA. Implemented separately from _mca_bus_dmamap_sync()
410  * so that it's available for one-shot setup.
411  */
412 void
413 mca_dma_set_ioport(int dma, uint16_t port)
414 {
415 #if 0
416 	/* Disable access to dma channel. */
417 	bus_space_write_1(dmaiot, dmacmdh, 0, DMACMD_MASK | dma);
418 
419 	/* Set I/O port to use for DMA */
420 	bus_space_write_1(dmaiot, dmacmdh, 0, DMACMD_SET_IO | dma);
421 	bus_space_write_1(dmaiot, dmaexech, 0, port & 0xff);
422 	bus_space_write_1(dmaiot, dmaexech, 0, (port >> 8) & 0xff);
423 
424 	/* Enable access to DMA channel. */
425 	bus_space_write_1(dmaiot, dmacmdh, 0, DMACMD_RESET_MASK | dma);
426 #endif
427 }
428