xref: /netbsd-src/sys/arch/rs6000/mca/mca_machdep.c (revision 6ffcebdef2d12e889bb07686e6a3fc05ba46288e)
1 /*	$NetBSD: mca_machdep.c,v 1.6 2024/07/02 06:07:12 rin 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 1.6 2024/07/02 06:07:12 rin 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 *
mca_intr_evcnt(mca_chipset_tag_t ic,int irq)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
mca_attach_hook(device_t parent,device_t self,struct mcabus_attach_args * mba)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
mca_conf_read(mca_chipset_tag_t mc,int slot,int reg)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
mca_conf_write(mca_chipset_tag_t mc,int slot,int reg,int data)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 *
mca_intr_establish(mca_chipset_tag_t mc,mca_intr_handle_t ih,int level,int (* func)(void *),void * arg)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
mca_intr_disestablish(mca_chipset_tag_t mc,void * cookie)168 mca_intr_disestablish(mca_chipset_tag_t mc, void *cookie)
169 {
170 	intr_disestablish(cookie);
171 }
172 
173 
174 /*
175  * GCC 12 blames pointer reference to 0-th page, [0, 0xfff].
176  * XXX map to higher address as done for, e.g., arm by devmap?
177  */
178 #pragma GCC diagnostic push					/* XXX { */
179 #pragma GCC diagnostic ignored "-Warray-bounds"
180 
181 /*
182  * Handle a NMI.
183  * return true to panic system, false to ignore.
184  */
185 int
mca_nmi(void)186 mca_nmi(void)
187 {
188 	/*
189 	* PS/2 MCA devices can generate NMIs - we can find out which
190 	* slot generated it from the POS registers.
191 	*/
192 
193 	int 	slot, mcanmi=0;
194 
195 	/* if there is no MCA bus, call x86_nmi() */
196 	if (!MCA_system)
197 		goto out;
198 
199 	/* ensure motherboard setup is disabled */
200 	outb(MCA_MB_SETUP_REG, 0xff);
201 
202 	/* find if an MCA slot has the CHCK bit asserted (low) in POS 5 */
203 	for(slot=0; slot<MCA_MAX_SLOTS; slot++) {
204 		outb(MCA_ADAP_SETUP_REG, slot | MCA_ADAP_SET);
205 		if ((inb(MCA_POS_REG(5)) & MCA_POS5_CHCK) == 0) {
206 			mcanmi = 1;
207 			/* find if CHCK status is available in POS 6/7 */
208 			if((inb(MCA_POS_REG(5)) & MCA_POS5_CHCK_STAT) == 0)
209 				log(LOG_CRIT, "MCA NMI: slot %d, POS6=0x%02x, POS7=0x%02x\n",
210 					slot+1, inb(MCA_POS_REG(6)),
211 						inb(MCA_POS_REG(7)));
212 			else
213 				log(LOG_CRIT, "MCA NMI: slot %d\n", slot+1);
214 		}
215 	}
216 	outb(MCA_ADAP_SETUP_REG, 0);
217 
218    out:
219 	if (!mcanmi) {
220 		/* no CHCK bits asserted, assume ISA NMI */
221 		//return (x86_nmi());
222 		return 0;
223 	} else
224 		return(0);
225 }
226 
227 /*
228  * Realistically, we should probe for the presence of an MCA bus here, and
229  * return a reasonable value.  However, this port is never expected to run
230  * on anything other than MCA, so rather than write a bunch of complex code
231  * to find that we indeed have a bus, lets just assume we do.
232  */
233 void
mca_busprobe(void)234 mca_busprobe(void)
235 {
236 	MCA_system = 1;
237 }
238 
239 #define PORT_DISKLED	0x92
240 #define DISKLED_ON	0x40
241 
242 /*
243  * Light disk busy LED on IBM PS/2.
244  */
245 void
mca_disk_busy(void)246 mca_disk_busy(void)
247 {
248 	outb(PORT_DISKLED, inb(PORT_DISKLED) | DISKLED_ON);
249 }
250 
251 /*
252  * Turn off disk LED on IBM PS/2.
253  */
254 void
mca_disk_unbusy(void)255 mca_disk_unbusy(void)
256 {
257 	outb(PORT_DISKLED, inb(PORT_DISKLED) & ~DISKLED_ON);
258 }
259 
260 #pragma GCC diagnostic pop					/* XXX } */
261 
262 /*
263  * -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
264  * MCA DMA specific stuff. We use ISA routines for bulk of the work,
265  * since MCA shares much of the charasteristics with it. We just hook
266  * the DMA channel initialization and kick MCA DMA controller appropriately.
267  * -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
268  */
269 
270 #ifdef NOTYET
271 /*
272  * Synchronize a MCA DMA map.
273  */
274 static void
_mca_bus_dmamap_sync(bus_dma_tag_t t,bus_dmamap_t map,bus_addr_t offset,bus_size_t len,int ops)275 _mca_bus_dmamap_sync(bus_dma_tag_t t, bus_dmamap_t map, bus_addr_t offset,
276     bus_size_t len, int ops)
277 {
278 	struct rs6000_dma_cookie *cookie;
279 	bus_addr_t phys;
280 	bus_size_t cnt;
281 	int dmach, mode;
282 
283 	_bus_dmamap_sync(t, map, offset, len, ops);
284 
285 	/*
286 	 * Don't do anything if not using the DMA controller.
287 	 */
288 	if ((map->_dm_flags & _MCABUS_DMA_USEDMACTRL) == 0)
289 		return;
290 
291 	/*
292 	 * Don't do anything if not PRE* operation, allow only
293 	 * one of PREREAD and PREWRITE.
294 	 */
295 	if (ops != BUS_DMASYNC_PREREAD && ops != BUS_DMASYNC_PREWRITE)
296 		return;
297 
298 	cookie = (struct rs6000_dma_cookie *)map->_dm_cookie;
299 	dmach = (cookie->id_flags & 0xf0) >> 4;
300 
301 	phys = map->dm_segs[0].ds_addr;
302 	cnt = map->dm_segs[0].ds_len;
303 
304 	mode = DMACMD_MODE_XFER;
305 	mode |= (ops == BUS_DMASYNC_PREREAD)
306 			? DMACMD_MODE_READ : DMACMD_MODE_WRITE;
307 	if (map->_dm_flags & MCABUS_DMA_IOPORT)
308 		mode |= DMACMD_MODE_IOPORT;
309 
310 	/* Use 16bit DMA if requested */
311 	if (map->_dm_flags & MCABUS_DMA_16BIT) {
312 #ifdef DIAGNOSTIC
313 		if ((cnt % 2) != 0) {
314 			panic("_mca_bus_dmamap_sync: 16bit DMA and cnt %lu odd",
315 				cnt);
316 		}
317 #endif
318 		mode |= DMACMD_MODE_16BIT;
319 		cnt /= 2;
320 	}
321 
322 	/*
323 	 * Initialize the MCA DMA controller appropriately. The exact
324 	 * sequence to setup the controller is taken from Minix.
325 	 */
326 
327 	/* Disable access to DMA channel. */
328 	bus_space_write_1(dmaiot, dmacmdh, 0, DMACMD_MASK | dmach);
329 
330 	/* Set the transfer mode. */
331 	bus_space_write_1(dmaiot, dmacmdh, 0, DMACMD_SET_MODE | dmach);
332 	bus_space_write_1(dmaiot, dmaexech, 0, mode);
333 
334 	/* Set the address byte pointer. */
335 	bus_space_write_1(dmaiot, dmacmdh, 0, DMACMD_SET_ADDR | dmach);
336 	/* address bits 0..7   */
337 	bus_space_write_1(dmaiot, dmaexech, 0, (phys >> 0) & 0xff);
338 	/* address bits 8..15  */
339 	bus_space_write_1(dmaiot, dmaexech, 0, (phys >> 8) & 0xff);
340 	/* address bits 16..23  */
341 	bus_space_write_1(dmaiot, dmaexech, 0, (phys >> 16) & 0xff);
342 
343 	/* Set the count byte pointer */
344 	bus_space_write_1(dmaiot, dmacmdh, 0, DMACMD_SET_CNT | dmach);
345 	/* count bits 0..7     */
346 	bus_space_write_1(dmaiot, dmaexech, 0, ((cnt - 1) >> 0) & 0xff);
347 	/* count bits 8..15    */
348 	bus_space_write_1(dmaiot, dmaexech, 0, ((cnt - 1) >> 8) & 0xff);
349 
350 	/* Enable access to DMA channel. */
351 	bus_space_write_1(dmaiot, dmacmdh, 0, DMACMD_RESET_MASK | dmach);
352 }
353 #endif
354 
355 /*
356  * Allocate a DMA map, and set up DMA channel.
357  */
358 int
mca_dmamap_create(bus_dma_tag_t t,bus_size_t size,int flags,bus_dmamap_t * dmamp,int dmach)359 mca_dmamap_create(bus_dma_tag_t t, bus_size_t size, int flags,
360     bus_dmamap_t *dmamp, int dmach)
361 {
362 #if 0
363 	int error;
364 	struct rs6000_dma_cookie *cookie;
365 
366 #ifdef DEBUG
367 	/* Sanity check */
368 	if (dmach < 0 || dmach >= MAX_DMA_CHANNELS) {
369 		printf("mcadma_create: invalid DMA channel %d\n",
370 			dmach);
371 		return (EINVAL);
372 	}
373 
374 	if (size > 65536) {
375 		panic("mca_dmamap_create: dmamap sz %ld > 65536",
376 		    (long) size);
377 	}
378 #endif
379 
380 	/*
381 	 * MCA DMA transfer can be maximum 65536 bytes long and must
382 	 * be in one chunk. No specific boundary constraints are present.
383 	 */
384 	if ((error = _bus_dmamap_create(t, size, 1, 65536, 0, flags, dmamp)))
385 		return (error);
386 
387 	cookie = (struct rs6000_dma_cookie *) (*dmamp)->_dm_cookie;
388 
389 	if (cookie == NULL) {
390 		/*
391 		 * Allocate our cookie if not yet done.
392 		 */
393 		cookie = kmem_zalloc(sizeof(struct rs6000_dma_cookie),
394 		    ((flags & BUS_DMA_NOWAIT) ? KM_SLEEP : KM_NOSLEEP));
395 		if (cookie == NULL) {
396 
397 			return ENOMEM;
398 		}
399 		(*dmamp)->_dm_cookie = cookie;
400 	}
401 
402 
403 	/* Encode DMA channel */
404 	cookie->id_flags &= 0x0f;
405 	cookie->id_flags |= dmach << 4;
406 
407 	/* Mark the dmamap as using DMA controller. Some devices
408 	 * drive DMA themselves, and don't need the MCA DMA controller.
409 	 * To distinguish the two, use a flag for dmamaps which use the DMA
410 	 * controller.
411  	 */
412 	(*dmamp)->_dm_flags |= _MCABUS_DMA_USEDMACTRL;
413 #endif
414 	return (0);
415 }
416 
417 /*
418  * Set I/O port for DMA. Implemented separately from _mca_bus_dmamap_sync()
419  * so that it's available for one-shot setup.
420  */
421 void
mca_dma_set_ioport(int dma,uint16_t port)422 mca_dma_set_ioport(int dma, uint16_t port)
423 {
424 #if 0
425 	/* Disable access to dma channel. */
426 	bus_space_write_1(dmaiot, dmacmdh, 0, DMACMD_MASK | dma);
427 
428 	/* Set I/O port to use for DMA */
429 	bus_space_write_1(dmaiot, dmacmdh, 0, DMACMD_SET_IO | dma);
430 	bus_space_write_1(dmaiot, dmaexech, 0, port & 0xff);
431 	bus_space_write_1(dmaiot, dmaexech, 0, (port >> 8) & 0xff);
432 
433 	/* Enable access to DMA channel. */
434 	bus_space_write_1(dmaiot, dmacmdh, 0, DMACMD_RESET_MASK | dma);
435 #endif
436 }
437