xref: /netbsd-src/sys/dev/isa/cs89x0isa.c (revision 077d1c0f365db1f9f0315d24fd965951eb1d90f2)
1 /* $NetBSD: cs89x0isa.c,v 1.20 2021/08/02 12:56:24 andvar Exp $ */
2 
3 /*
4  * Copyright 1997
5  * Digital Equipment Corporation. All rights reserved.
6  *
7  * This software is furnished under license and may be used and
8  * copied only in accordance with the following terms and conditions.
9  * Subject to these conditions, you may download, copy, install,
10  * use, modify and distribute this software in source and/or binary
11  * form. No title or ownership is transferred hereby.
12  *
13  * 1) Any source code used, modified or distributed must reproduce
14  *    and retain this copyright notice and list of conditions as
15  *    they appear in the source file.
16  *
17  * 2) No right is granted to use any trade name, trademark, or logo of
18  *    Digital Equipment Corporation. Neither the "Digital Equipment
19  *    Corporation" name nor any trademark or logo of Digital Equipment
20  *    Corporation may be used to endorse or promote products derived
21  *    from this software without the prior written permission of
22  *    Digital Equipment Corporation.
23  *
24  * 3) This software is provided "AS-IS" and any express or implied
25  *    warranties, including but not limited to, any implied warranties
26  *    of merchantability, fitness for a particular purpose, or
27  *    non-infringement are disclaimed. In no event shall DIGITAL be
28  *    liable for any damages whatsoever, and in particular, DIGITAL
29  *    shall not be liable for special, indirect, consequential, or
30  *    incidental damages or damages for lost profits, loss of
31  *    revenue or loss of use, whether such damages arise in contract,
32  *    negligence, tort, under statute, in equity, at law or otherwise,
33  *    even if advised of the possibility of such damage.
34  */
35 
36 /* isa DMA routines for cs89x0 */
37 
38 #include <sys/cdefs.h>
39 __KERNEL_RCSID(0, "$NetBSD: cs89x0isa.c,v 1.20 2021/08/02 12:56:24 andvar Exp $");
40 
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/mbuf.h>
44 #include <sys/socket.h>
45 #include <sys/device.h>
46 
47 #include <net/if.h>
48 #include <net/if_ether.h>
49 #include <net/if_media.h>
50 
51 #include <sys/bus.h>
52 
53 #include <dev/isa/isareg.h>
54 #include <dev/isa/isavar.h>
55 #include <dev/isa/isadmavar.h>
56 
57 #include <dev/ic/cs89x0reg.h>
58 #include <dev/ic/cs89x0var.h>
59 #include <dev/isa/cs89x0isavar.h>
60 
61 #define DMA_STATUS_BITS 0x0007	/* bit masks for checking DMA status */
62 #define DMA_STATUS_OK 0x0004
63 
64 void
cs_isa_dma_attach(struct cs_softc * sc)65 cs_isa_dma_attach(struct cs_softc *sc)
66 {
67 	struct cs_softc_isa *isc = (struct cs_softc_isa *)sc;
68 
69 	if (isc->sc_drq == ISA_UNKNOWN_DRQ)
70 		printf("%s: DMA channel unspecified, not using DMA\n",
71 		    device_xname(sc->sc_dev));
72 	else if (isc->sc_drq < 5 || isc->sc_drq > 7)
73 		printf("%s: invalid DMA channel, not using DMA\n",
74 		    device_xname(sc->sc_dev));
75 	else {
76 		bus_size_t maxsize;
77 		bus_addr_t dma_addr;
78 
79 		maxsize = isa_dmamaxsize(isc->sc_ic, isc->sc_drq);
80 		if (maxsize < CS8900_DMASIZE) {
81 			printf("%s: max DMA size %lu is"
82 			    " less than required %d\n",
83 			    device_xname(sc->sc_dev), (u_long)maxsize,
84 			    CS8900_DMASIZE);
85 			goto after_dma_block;
86 		}
87 
88 		if (isa_drq_alloc(isc->sc_ic, isc->sc_drq) != 0) {
89 			aprint_error_dev(sc->sc_dev,
90 			    "unable to reserve drq %d\n",
91 			    isc->sc_drq);
92 			goto after_dma_block;
93 		}
94 
95 		if (isa_dmamap_create(isc->sc_ic, isc->sc_drq,
96 		    CS8900_DMASIZE, BUS_DMA_NOWAIT|BUS_DMA_ALLOCNOW) != 0) {
97 			aprint_error_dev(sc->sc_dev,
98 			    "unable to create ISA DMA map\n");
99 			goto after_dma_block;
100 		}
101 		if (isa_dmamem_alloc(isc->sc_ic, isc->sc_drq,
102 		    CS8900_DMASIZE, &dma_addr, BUS_DMA_NOWAIT) != 0) {
103 			aprint_error_dev(sc->sc_dev,
104 			    "unable to allocate DMA buffer\n");
105 			goto after_dma_block;
106 		}
107 		if (isa_dmamem_map(isc->sc_ic, isc->sc_drq, dma_addr,
108 		    CS8900_DMASIZE, (void **)&isc->sc_dmabase,
109 		       BUS_DMA_NOWAIT | BUS_DMA_COHERENT /* XXX */ ) != 0) {
110 			aprint_error_dev(sc->sc_dev,
111 			    "unable to map DMA buffer\n");
112 			isa_dmamem_free(isc->sc_ic, isc->sc_drq, dma_addr,
113 			    CS8900_DMASIZE);
114 			goto after_dma_block;
115 		}
116 
117 		isc->sc_dmasize = CS8900_DMASIZE;
118 		sc->sc_cfgflags |= CFGFLG_DMA_MODE;
119 		isc->sc_dmaaddr = dma_addr;
120 after_dma_block:
121 		;
122 	}
123 }
124 
cs_isa_dma_chipinit(struct cs_softc * sc)125 void cs_isa_dma_chipinit(struct cs_softc *sc)
126 {
127 	struct cs_softc_isa *isc = (struct cs_softc_isa *)sc;
128 
129 	if (sc->sc_cfgflags & CFGFLG_DMA_MODE) {
130 		/*
131 		 * First we program the DMA controller and ensure the memory
132 		 * buffer is valid. If it isn't then we just go on without
133 		 * DMA.
134 		 */
135 		if (isa_dmastart(isc->sc_ic, isc->sc_drq, isc->sc_dmabase,
136 		    isc->sc_dmasize, NULL, DMAMODE_READ | DMAMODE_LOOPDEMAND,
137 		    BUS_DMA_NOWAIT)) {
138 			/* XXX XXX XXX */
139 			panic("%s: unable to start DMA",
140 			    device_xname(sc->sc_dev));
141 		}
142 		isc->sc_dmacur = isc->sc_dmabase;
143 
144 		/* interrupt when a DMA'd frame is received */
145 		CS_WRITE_PACKET_PAGE(sc, PKTPG_RX_CFG,
146 		    RX_CFG_ALL_IE | RX_CFG_RX_DMA_ONLY);
147 
148 		/*
149 		 * set the DMA burst bit so we don't tie up the bus for too
150 		 * long.
151 		 */
152 		if (isc->sc_dmasize == 16384) {
153 			CS_WRITE_PACKET_PAGE(sc, PKTPG_BUS_CTL,
154 			    ((CS_READ_PACKET_PAGE(sc, PKTPG_BUS_CTL) &
155 			     ~BUS_CTL_DMA_SIZE) | BUS_CTL_DMA_BURST));
156 		} else { /* use 64K */
157 			CS_WRITE_PACKET_PAGE(sc, PKTPG_BUS_CTL,
158 			    CS_READ_PACKET_PAGE(sc, PKTPG_BUS_CTL) |
159 			     BUS_CTL_DMA_SIZE | BUS_CTL_DMA_BURST);
160 		}
161 
162 		CS_WRITE_PACKET_PAGE(sc, PKTPG_DMA_CHANNEL, isc->sc_drq - 5);
163 	}
164 }
165 
cs_process_rx_dma(struct cs_softc * sc)166 void cs_process_rx_dma(struct cs_softc *sc)
167 {
168 	struct cs_softc_isa *isc = (struct cs_softc_isa *)sc;
169 	struct ifnet *ifp;
170 	u_int16_t num_dma_frames;
171 	u_int16_t pkt_length;
172 	u_int16_t status;
173 	u_int to_copy;
174 	char *dma_mem_ptr;
175 	struct mbuf *m;
176 	u_char *pBuff;
177 	int pad;
178 
179 	/* initialise the pointers */
180 	ifp = &sc->sc_ethercom.ec_if;
181 
182 	/* Read the number of frames DMAed. */
183 	num_dma_frames = CS_READ_PACKET_PAGE(sc, PKTPG_DMA_FRAME_COUNT);
184 	num_dma_frames &= (u_int16_t) (0x0fff);
185 
186 	/*
187 	 * Loop till number of DMA frames ready to read is zero. After
188 	 * reading the frame out of memory we must check if any have been
189 	 * received while we were processing
190 	 */
191 	while (num_dma_frames != 0) {
192 		dma_mem_ptr = isc->sc_dmacur;
193 
194 		/*
195 		 * process all of the DMA frames in memory
196 		 *
197 		 * This loop relies on the dma_mem_ptr variable being set to the
198 		 * next frames start address.
199 		 */
200 		for (; num_dma_frames > 0; num_dma_frames--) {
201 
202 			/*
203 			 * Get the length and status of the packet. Only the
204 			 * status is guaranteed to be at dma_mem_ptr, ie need
205 			 * to check for wraparound before reading the length
206 			 */
207 			status = *((u_int16_t *) dma_mem_ptr);
208 			dma_mem_ptr += 2;
209 			if (dma_mem_ptr > (isc->sc_dmabase + isc->sc_dmasize)) {
210 				dma_mem_ptr = isc->sc_dmabase;
211 			}
212 			pkt_length = *((u_int16_t *) dma_mem_ptr);
213 			dma_mem_ptr += 2;
214 
215 			/* Do some sanity checks on the length and status. */
216 			if ((pkt_length > ETHER_MAX_LEN) ||
217 			    ((status & DMA_STATUS_BITS) != DMA_STATUS_OK)) {
218 				/*
219 				 * the SCO driver kills the adapter in this
220 				 * situation
221 				 */
222 				/*
223 				 * should increment the error count and reset
224 				 * the DMA operation.
225 				 */
226 				printf("%s: cs_process_rx_dma: "
227 				    "DMA buffer out of sync about to reset\n",
228 				    device_xname(sc->sc_dev));
229 				if_statinc(ifp, if_ierrors);
230 
231 				/* skip the rest of the DMA buffer */
232 				isa_dmaabort(isc->sc_ic, isc->sc_drq);
233 
234 				/* now reset the chip and reinitialise */
235 				cs_init(&sc->sc_ethercom.ec_if);
236 				return;
237 			}
238 			/* Check the status of the received packet. */
239 			if (status & RX_EVENT_RX_OK) {
240 				/* get a new mbuf */
241 				MGETHDR(m, M_DONTWAIT, MT_DATA);
242 				if (m == 0) {
243 					printf("%s: cs_process_rx_dma: "
244 					    "unable to allocate mbuf\n",
245 					    device_xname(sc->sc_dev));
246 					if_statinc(ifp, if_ierrors);
247 					/*
248 					 * couldn't allocate an mbuf so
249 					 * things are not good, may as well
250 					 * drop all the packets I think.
251 					 */
252 					CS_READ_PACKET_PAGE(sc,
253 					    PKTPG_DMA_FRAME_COUNT);
254 
255 					/* now reset DMA operation */
256 					isa_dmaabort(isc->sc_ic, isc->sc_drq);
257 
258 					/*
259 					 * now reset the chip and
260 					 * reinitialise
261 					 */
262 					cs_init(&sc->sc_ethercom.ec_if);
263 					return;
264 				}
265 				/*
266 				 * save processing by always using a mbuf
267 				 * cluster, guaranteed to fit packet
268 				 */
269 				MCLGET(m, M_DONTWAIT);
270 				if ((m->m_flags & M_EXT) == 0) {
271 					/* couldn't allocate an mbuf cluster */
272 					printf("%s: cs_process_rx_dma: "
273 					    "unable to allocate a cluster\n",
274 					    device_xname(sc->sc_dev));
275 					m_freem(m);
276 
277 					/* skip the frame */
278 					CS_READ_PACKET_PAGE(sc, PKTPG_DMA_FRAME_COUNT);
279 					isa_dmaabort(isc->sc_ic, isc->sc_drq);
280 
281 					/*
282 					 * now reset the chip and
283 					 * reinitialise
284 					 */
285 					cs_init(&sc->sc_ethercom.ec_if);
286 					return;
287 				}
288 				m_set_rcvif(m, ifp);
289 				m->m_pkthdr.len = pkt_length;
290 				m->m_len = pkt_length;
291 
292 				/*
293 				 * align ip header on word boundary for
294 				 * ipintr
295 				 */
296 				pad = ALIGN(sizeof(struct ether_header)) -
297 				    sizeof(struct ether_header);
298 				m->m_data += pad;
299 
300 				/*
301 				 * set up the buffer pointer to point to the
302 				 * data area
303 				 */
304 				pBuff = mtod(m, char *);
305 
306 				/*
307 				 * Read the frame into free_pktbuf
308 				 * The buffer is circular buffer, either
309 				 * 16K or 64K in length.
310 				 *
311 				 * need to check where the end of the buffer
312 				 * is and go back to the start.
313 				 */
314 				if ((dma_mem_ptr + pkt_length) <
315 				    (isc->sc_dmabase + isc->sc_dmasize)) {
316 					/*
317 					 * No wrap around. Copy the frame
318 					 * header
319 					 */
320 					memcpy(pBuff, dma_mem_ptr, pkt_length);
321 					dma_mem_ptr += pkt_length;
322 				} else {
323 					to_copy = (u_int)
324 					    ((isc->sc_dmabase + isc->sc_dmasize) -
325 					    dma_mem_ptr);
326 
327 					/* Copy the first half of the frame. */
328 					memcpy(pBuff, dma_mem_ptr, to_copy);
329 					pBuff += to_copy;
330 
331 					/*
332 		                         * Rest of the frame is to be read
333 		                         * from the first byte of the DMA
334 		                         * memory.
335 		                         */
336 					/*
337 					 * Get the number of bytes leftout in
338 					 * the frame.
339 					 */
340 					to_copy = pkt_length - to_copy;
341 
342 					dma_mem_ptr = isc->sc_dmabase;
343 
344 					/* Copy rest of the frame. */
345 					memcpy(pBuff, dma_mem_ptr, to_copy);
346 					dma_mem_ptr += to_copy;
347 				}
348 
349 				cs_ether_input(sc, m);
350 			}
351 			/* (status & RX_OK) */
352 			else {
353 				/* the frame was not received OK */
354 				/* Increment the input error count */
355 				if_statinc(ifp, if_ierrors);
356 
357 				/*
358 				 * If debugging is enabled then log error
359 				 * messages if we got any.
360 				 */
361 				if ((ifp->if_flags & IFF_DEBUG) &&
362 				    status != REG_NUM_RX_EVENT)
363 					cs_print_rx_errors(sc, status);
364 			}
365 			/*
366 			 * now update the current frame pointer. the
367 			 * dma_mem_ptr should point to the next packet to be
368 			 * received, without the alignment considerations.
369 			 *
370 			 * The cs8900 pads all frames to start at the next 32bit
371 			 * aligned address. hence we need to pad our offset
372 			 * pointer.
373 			 */
374 			dma_mem_ptr += 3;
375 			dma_mem_ptr = (char *)
376 			    ((long) dma_mem_ptr & 0xfffffffc);
377 			if (dma_mem_ptr < (isc->sc_dmabase + isc->sc_dmasize)) {
378 				isc->sc_dmacur = dma_mem_ptr;
379 			} else {
380 				dma_mem_ptr = isc->sc_dmacur = isc->sc_dmabase;
381 			}
382 		} /* for all frames */
383 		/* Read the number of frames DMAed again. */
384 		num_dma_frames = CS_READ_PACKET_PAGE(sc, PKTPG_DMA_FRAME_COUNT);
385 		num_dma_frames &= (u_int16_t) (0x0fff);
386 	} /* while there are frames left */
387 }
388