xref: /openbmc/linux/drivers/net/wan/hd64570.c (revision 1edd0337)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Hitachi SCA HD64570 driver for Linux
4  *
5  * Copyright (C) 1998-2003 Krzysztof Halasa <khc@pm.waw.pl>
6  *
7  * Source of information: Hitachi HD64570 SCA User's Manual
8  *
9  * We use the following SCA memory map:
10  *
11  * Packet buffer descriptor rings - starting from winbase or win0base:
12  * rx_ring_buffers * sizeof(pkt_desc) = logical channel #0 RX ring
13  * tx_ring_buffers * sizeof(pkt_desc) = logical channel #0 TX ring
14  * rx_ring_buffers * sizeof(pkt_desc) = logical channel #1 RX ring (if used)
15  * tx_ring_buffers * sizeof(pkt_desc) = logical channel #1 TX ring (if used)
16  *
17  * Packet data buffers - starting from winbase + buff_offset:
18  * rx_ring_buffers * HDLC_MAX_MRU     = logical channel #0 RX buffers
19  * tx_ring_buffers * HDLC_MAX_MRU     = logical channel #0 TX buffers
20  * rx_ring_buffers * HDLC_MAX_MRU     = logical channel #0 RX buffers (if used)
21  * tx_ring_buffers * HDLC_MAX_MRU     = logical channel #0 TX buffers (if used)
22  */
23 
24 #include <linux/bitops.h>
25 #include <linux/errno.h>
26 #include <linux/fcntl.h>
27 #include <linux/hdlc.h>
28 #include <linux/in.h>
29 #include <linux/interrupt.h>
30 #include <linux/ioport.h>
31 #include <linux/jiffies.h>
32 #include <linux/kernel.h>
33 #include <linux/module.h>
34 #include <linux/netdevice.h>
35 #include <linux/skbuff.h>
36 #include <linux/string.h>
37 #include <linux/types.h>
38 #include <asm/io.h>
39 #include <linux/uaccess.h>
40 #include "hd64570.h"
41 
42 #define get_msci(port)	  (phy_node(port) ?   MSCI1_OFFSET :   MSCI0_OFFSET)
43 #define get_dmac_rx(port) (phy_node(port) ? DMAC1RX_OFFSET : DMAC0RX_OFFSET)
44 #define get_dmac_tx(port) (phy_node(port) ? DMAC1TX_OFFSET : DMAC0TX_OFFSET)
45 
46 #define SCA_INTR_MSCI(node)    (node ? 0x10 : 0x01)
47 #define SCA_INTR_DMAC_RX(node) (node ? 0x20 : 0x02)
48 #define SCA_INTR_DMAC_TX(node) (node ? 0x40 : 0x04)
49 
50 static inline struct net_device *port_to_dev(port_t *port)
51 {
52 	return port->dev;
53 }
54 
55 static inline int sca_intr_status(card_t *card)
56 {
57 	u8 result = 0;
58 	u8 isr0 = sca_in(ISR0, card);
59 	u8 isr1 = sca_in(ISR1, card);
60 
61 	if (isr1 & 0x03)
62 		result |= SCA_INTR_DMAC_RX(0);
63 	if (isr1 & 0x0C)
64 		result |= SCA_INTR_DMAC_TX(0);
65 	if (isr1 & 0x30)
66 		result |= SCA_INTR_DMAC_RX(1);
67 	if (isr1 & 0xC0)
68 		result |= SCA_INTR_DMAC_TX(1);
69 	if (isr0 & 0x0F)
70 		result |= SCA_INTR_MSCI(0);
71 	if (isr0 & 0xF0)
72 		result |= SCA_INTR_MSCI(1);
73 
74 	if (!(result & SCA_INTR_DMAC_TX(0)))
75 		if (sca_in(DSR_TX(0), card) & DSR_EOM)
76 			result |= SCA_INTR_DMAC_TX(0);
77 	if (!(result & SCA_INTR_DMAC_TX(1)))
78 		if (sca_in(DSR_TX(1), card) & DSR_EOM)
79 			result |= SCA_INTR_DMAC_TX(1);
80 
81 	return result;
82 }
83 
84 static inline port_t *dev_to_port(struct net_device *dev)
85 {
86 	return dev_to_hdlc(dev)->priv;
87 }
88 
89 static inline u16 next_desc(port_t *port, u16 desc, int transmit)
90 {
91 	return (desc + 1) % (transmit ? port_to_card(port)->tx_ring_buffers
92 			     : port_to_card(port)->rx_ring_buffers);
93 }
94 
95 static inline u16 desc_abs_number(port_t *port, u16 desc, int transmit)
96 {
97 	u16 rx_buffs = port_to_card(port)->rx_ring_buffers;
98 	u16 tx_buffs = port_to_card(port)->tx_ring_buffers;
99 
100 	desc %= (transmit ? tx_buffs : rx_buffs); // called with "X + 1" etc.
101 	return log_node(port) * (rx_buffs + tx_buffs) +
102 		transmit * rx_buffs + desc;
103 }
104 
105 static inline u16 desc_offset(port_t *port, u16 desc, int transmit)
106 {
107 	/* Descriptor offset always fits in 16 bits */
108 	return desc_abs_number(port, desc, transmit) * sizeof(pkt_desc);
109 }
110 
111 static inline pkt_desc __iomem *desc_address(port_t *port, u16 desc,
112 					     int transmit)
113 {
114 #ifdef PAGE0_ALWAYS_MAPPED
115 	return (pkt_desc __iomem *)(win0base(port_to_card(port))
116 				    + desc_offset(port, desc, transmit));
117 #else
118 	return (pkt_desc __iomem *)(winbase(port_to_card(port))
119 				    + desc_offset(port, desc, transmit));
120 #endif
121 }
122 
123 static inline u32 buffer_offset(port_t *port, u16 desc, int transmit)
124 {
125 	return port_to_card(port)->buff_offset +
126 		desc_abs_number(port, desc, transmit) * (u32)HDLC_MAX_MRU;
127 }
128 
129 static inline void sca_set_carrier(port_t *port)
130 {
131 	if (!(sca_in(get_msci(port) + ST3, port_to_card(port)) & ST3_DCD)) {
132 #ifdef DEBUG_LINK
133 		printk(KERN_DEBUG "%s: sca_set_carrier on\n",
134 		       port_to_dev(port)->name);
135 #endif
136 		netif_carrier_on(port_to_dev(port));
137 	} else {
138 #ifdef DEBUG_LINK
139 		printk(KERN_DEBUG "%s: sca_set_carrier off\n",
140 		       port_to_dev(port)->name);
141 #endif
142 		netif_carrier_off(port_to_dev(port));
143 	}
144 }
145 
146 static void sca_init_port(port_t *port)
147 {
148 	card_t *card = port_to_card(port);
149 	int transmit, i;
150 
151 	port->rxin = 0;
152 	port->txin = 0;
153 	port->txlast = 0;
154 
155 #ifndef PAGE0_ALWAYS_MAPPED
156 	openwin(card, 0);
157 #endif
158 
159 	for (transmit = 0; transmit < 2; transmit++) {
160 		u16 dmac = transmit ? get_dmac_tx(port) : get_dmac_rx(port);
161 		u16 buffs = transmit ? card->tx_ring_buffers
162 			: card->rx_ring_buffers;
163 
164 		for (i = 0; i < buffs; i++) {
165 			pkt_desc __iomem *desc = desc_address(port, i, transmit);
166 			u16 chain_off = desc_offset(port, i + 1, transmit);
167 			u32 buff_off = buffer_offset(port, i, transmit);
168 
169 			writew(chain_off, &desc->cp);
170 			writel(buff_off, &desc->bp);
171 			writew(0, &desc->len);
172 			writeb(0, &desc->stat);
173 		}
174 
175 		/* DMA disable - to halt state */
176 		sca_out(0, transmit ? DSR_TX(phy_node(port)) :
177 			DSR_RX(phy_node(port)), card);
178 		/* software ABORT - to initial state */
179 		sca_out(DCR_ABORT, transmit ? DCR_TX(phy_node(port)) :
180 			DCR_RX(phy_node(port)), card);
181 
182 		/* current desc addr */
183 		sca_out(0, dmac + CPB, card); /* pointer base */
184 		sca_outw(desc_offset(port, 0, transmit), dmac + CDAL, card);
185 		if (!transmit)
186 			sca_outw(desc_offset(port, buffs - 1, transmit),
187 				 dmac + EDAL, card);
188 		else
189 			sca_outw(desc_offset(port, 0, transmit), dmac + EDAL,
190 				 card);
191 
192 		/* clear frame end interrupt counter */
193 		sca_out(DCR_CLEAR_EOF, transmit ? DCR_TX(phy_node(port)) :
194 			DCR_RX(phy_node(port)), card);
195 
196 		if (!transmit) { /* Receive */
197 			/* set buffer length */
198 			sca_outw(HDLC_MAX_MRU, dmac + BFLL, card);
199 			/* Chain mode, Multi-frame */
200 			sca_out(0x14, DMR_RX(phy_node(port)), card);
201 			sca_out(DIR_EOME | DIR_BOFE, DIR_RX(phy_node(port)),
202 				card);
203 			/* DMA enable */
204 			sca_out(DSR_DE, DSR_RX(phy_node(port)), card);
205 		} else {	/* Transmit */
206 			/* Chain mode, Multi-frame */
207 			sca_out(0x14, DMR_TX(phy_node(port)), card);
208 			/* enable underflow interrupts */
209 			sca_out(DIR_BOFE, DIR_TX(phy_node(port)), card);
210 		}
211 	}
212 	sca_set_carrier(port);
213 }
214 
215 #ifdef NEED_SCA_MSCI_INTR
216 /* MSCI interrupt service */
217 static inline void sca_msci_intr(port_t *port)
218 {
219 	u16 msci = get_msci(port);
220 	card_t *card = port_to_card(port);
221 	u8 stat = sca_in(msci + ST1, card); /* read MSCI ST1 status */
222 
223 	/* Reset MSCI TX underrun and CDCD status bit */
224 	sca_out(stat & (ST1_UDRN | ST1_CDCD), msci + ST1, card);
225 
226 	if (stat & ST1_UDRN) {
227 		/* TX Underrun error detected */
228 		port_to_dev(port)->stats.tx_errors++;
229 		port_to_dev(port)->stats.tx_fifo_errors++;
230 	}
231 
232 	if (stat & ST1_CDCD)
233 		sca_set_carrier(port);
234 }
235 #endif
236 
237 static inline void sca_rx(card_t *card, port_t *port, pkt_desc __iomem *desc,
238 			  u16 rxin)
239 {
240 	struct net_device *dev = port_to_dev(port);
241 	struct sk_buff *skb;
242 	u16 len;
243 	u32 buff;
244 	u32 maxlen;
245 	u8 page;
246 
247 	len = readw(&desc->len);
248 	skb = dev_alloc_skb(len);
249 	if (!skb) {
250 		dev->stats.rx_dropped++;
251 		return;
252 	}
253 
254 	buff = buffer_offset(port, rxin, 0);
255 	page = buff / winsize(card);
256 	buff = buff % winsize(card);
257 	maxlen = winsize(card) - buff;
258 
259 	openwin(card, page);
260 
261 	if (len > maxlen) {
262 		memcpy_fromio(skb->data, winbase(card) + buff, maxlen);
263 		openwin(card, page + 1);
264 		memcpy_fromio(skb->data + maxlen, winbase(card), len - maxlen);
265 	} else {
266 		memcpy_fromio(skb->data, winbase(card) + buff, len);
267 	}
268 
269 #ifndef PAGE0_ALWAYS_MAPPED
270 	openwin(card, 0);	/* select pkt_desc table page back */
271 #endif
272 	skb_put(skb, len);
273 #ifdef DEBUG_PKT
274 	printk(KERN_DEBUG "%s RX(%i):", dev->name, skb->len);
275 	debug_frame(skb);
276 #endif
277 	dev->stats.rx_packets++;
278 	dev->stats.rx_bytes += skb->len;
279 	skb->protocol = hdlc_type_trans(skb, dev);
280 	netif_rx(skb);
281 }
282 
283 /* Receive DMA interrupt service */
284 static inline void sca_rx_intr(port_t *port)
285 {
286 	struct net_device *dev = port_to_dev(port);
287 	u16 dmac = get_dmac_rx(port);
288 	card_t *card = port_to_card(port);
289 	u8 stat = sca_in(DSR_RX(phy_node(port)), card); /* read DMA Status */
290 
291 	/* Reset DSR status bits */
292 	sca_out((stat & (DSR_EOT | DSR_EOM | DSR_BOF | DSR_COF)) | DSR_DWE,
293 		DSR_RX(phy_node(port)), card);
294 
295 	if (stat & DSR_BOF)
296 		/* Dropped one or more frames */
297 		dev->stats.rx_over_errors++;
298 
299 	while (1) {
300 		u32 desc_off = desc_offset(port, port->rxin, 0);
301 		pkt_desc __iomem *desc;
302 		u32 cda = sca_inw(dmac + CDAL, card);
303 
304 		if (cda >= desc_off && (cda < desc_off + sizeof(pkt_desc)))
305 			break;	/* No frame received */
306 
307 		desc = desc_address(port, port->rxin, 0);
308 		stat = readb(&desc->stat);
309 		if (!(stat & ST_RX_EOM))
310 			port->rxpart = 1; /* partial frame received */
311 		else if ((stat & ST_ERROR_MASK) || port->rxpart) {
312 			dev->stats.rx_errors++;
313 			if (stat & ST_RX_OVERRUN)
314 				dev->stats.rx_fifo_errors++;
315 			else if ((stat & (ST_RX_SHORT | ST_RX_ABORT |
316 					  ST_RX_RESBIT)) || port->rxpart)
317 				dev->stats.rx_frame_errors++;
318 			else if (stat & ST_RX_CRC)
319 				dev->stats.rx_crc_errors++;
320 			if (stat & ST_RX_EOM)
321 				port->rxpart = 0; /* received last fragment */
322 		} else {
323 			sca_rx(card, port, desc, port->rxin);
324 		}
325 
326 		/* Set new error descriptor address */
327 		sca_outw(desc_off, dmac + EDAL, card);
328 		port->rxin = next_desc(port, port->rxin, 0);
329 	}
330 
331 	/* make sure RX DMA is enabled */
332 	sca_out(DSR_DE, DSR_RX(phy_node(port)), card);
333 }
334 
335 /* Transmit DMA interrupt service */
336 static inline void sca_tx_intr(port_t *port)
337 {
338 	struct net_device *dev = port_to_dev(port);
339 	u16 dmac = get_dmac_tx(port);
340 	card_t *card = port_to_card(port);
341 	u8 stat;
342 
343 	spin_lock(&port->lock);
344 
345 	stat = sca_in(DSR_TX(phy_node(port)), card); /* read DMA Status */
346 
347 	/* Reset DSR status bits */
348 	sca_out((stat & (DSR_EOT | DSR_EOM | DSR_BOF | DSR_COF)) | DSR_DWE,
349 		DSR_TX(phy_node(port)), card);
350 
351 	while (1) {
352 		pkt_desc __iomem *desc;
353 
354 		u32 desc_off = desc_offset(port, port->txlast, 1);
355 		u32 cda = sca_inw(dmac + CDAL, card);
356 
357 		if (cda >= desc_off && (cda < desc_off + sizeof(pkt_desc)))
358 			break;	/* Transmitter is/will_be sending this frame */
359 
360 		desc = desc_address(port, port->txlast, 1);
361 		dev->stats.tx_packets++;
362 		dev->stats.tx_bytes += readw(&desc->len);
363 		writeb(0, &desc->stat);	/* Free descriptor */
364 		port->txlast = next_desc(port, port->txlast, 1);
365 	}
366 
367 	netif_wake_queue(dev);
368 	spin_unlock(&port->lock);
369 }
370 
371 static irqreturn_t sca_intr(int irq, void *dev_id)
372 {
373 	card_t *card = dev_id;
374 	int i;
375 	u8 stat;
376 	int handled = 0;
377 	u8 page = sca_get_page(card);
378 
379 	while ((stat = sca_intr_status(card)) != 0) {
380 		handled = 1;
381 		for (i = 0; i < 2; i++) {
382 			port_t *port = get_port(card, i);
383 
384 			if (port) {
385 				if (stat & SCA_INTR_MSCI(i))
386 					sca_msci_intr(port);
387 
388 				if (stat & SCA_INTR_DMAC_RX(i))
389 					sca_rx_intr(port);
390 
391 				if (stat & SCA_INTR_DMAC_TX(i))
392 					sca_tx_intr(port);
393 			}
394 		}
395 	}
396 
397 	openwin(card, page);		/* Restore original page */
398 	return IRQ_RETVAL(handled);
399 }
400 
401 static void sca_set_port(port_t *port)
402 {
403 	card_t *card = port_to_card(port);
404 	u16 msci = get_msci(port);
405 	u8 md2 = sca_in(msci + MD2, card);
406 	unsigned int tmc, br = 10, brv = 1024;
407 
408 	if (port->settings.clock_rate > 0) {
409 		/* Try lower br for better accuracy*/
410 		do {
411 			br--;
412 			brv >>= 1; /* brv = 2^9 = 512 max in specs */
413 
414 			/* Baud Rate = CLOCK_BASE / TMC / 2^BR */
415 			tmc = CLOCK_BASE / brv / port->settings.clock_rate;
416 		} while (br > 1 && tmc <= 128);
417 
418 		if (tmc < 1) {
419 			tmc = 1;
420 			br = 0;	/* For baud=CLOCK_BASE we use tmc=1 br=0 */
421 			brv = 1;
422 		} else if (tmc > 255) {
423 			tmc = 256; /* tmc=0 means 256 - low baud rates */
424 		}
425 
426 		port->settings.clock_rate = CLOCK_BASE / brv / tmc;
427 	} else {
428 		br = 9; /* Minimum clock rate */
429 		tmc = 256;	/* 8bit = 0 */
430 		port->settings.clock_rate = CLOCK_BASE / (256 * 512);
431 	}
432 
433 	port->rxs = (port->rxs & ~CLK_BRG_MASK) | br;
434 	port->txs = (port->txs & ~CLK_BRG_MASK) | br;
435 	port->tmc = tmc;
436 
437 	/* baud divisor - time constant*/
438 	sca_out(port->tmc, msci + TMC, card);
439 
440 	/* Set BRG bits */
441 	sca_out(port->rxs, msci + RXS, card);
442 	sca_out(port->txs, msci + TXS, card);
443 
444 	if (port->settings.loopback)
445 		md2 |= MD2_LOOPBACK;
446 	else
447 		md2 &= ~MD2_LOOPBACK;
448 
449 	sca_out(md2, msci + MD2, card);
450 }
451 
452 static void sca_open(struct net_device *dev)
453 {
454 	port_t *port = dev_to_port(dev);
455 	card_t *card = port_to_card(port);
456 	u16 msci = get_msci(port);
457 	u8 md0, md2;
458 
459 	switch (port->encoding) {
460 	case ENCODING_NRZ:
461 		md2 = MD2_NRZ;
462 		break;
463 	case ENCODING_NRZI:
464 		md2 = MD2_NRZI;
465 		break;
466 	case ENCODING_FM_MARK:
467 		md2 = MD2_FM_MARK;
468 		break;
469 	case ENCODING_FM_SPACE:
470 		md2 = MD2_FM_SPACE;
471 		break;
472 	default:
473 		md2 = MD2_MANCHESTER;
474 	}
475 
476 	if (port->settings.loopback)
477 		md2 |= MD2_LOOPBACK;
478 
479 	switch (port->parity) {
480 	case PARITY_CRC16_PR0:
481 		md0 = MD0_HDLC | MD0_CRC_16_0;
482 		break;
483 	case PARITY_CRC16_PR1:
484 		md0 = MD0_HDLC | MD0_CRC_16;
485 		break;
486 	case PARITY_CRC16_PR0_CCITT:
487 		md0 = MD0_HDLC | MD0_CRC_ITU_0;
488 		break;
489 	case PARITY_CRC16_PR1_CCITT:
490 		md0 = MD0_HDLC | MD0_CRC_ITU;
491 		break;
492 	default:
493 		md0 = MD0_HDLC | MD0_CRC_NONE;
494 	}
495 
496 	sca_out(CMD_RESET, msci + CMD, card);
497 	sca_out(md0, msci + MD0, card);
498 	sca_out(0x00, msci + MD1, card); /* no address field check */
499 	sca_out(md2, msci + MD2, card);
500 	sca_out(0x7E, msci + IDL, card); /* flag character 0x7E */
501 	sca_out(CTL_IDLE, msci + CTL, card);
502 
503 	/* Allow at least 8 bytes before requesting RX DMA operation */
504 	/* TX with higher priority and possibly with shorter transfers */
505 	sca_out(0x07, msci + RRC, card); /* +1=RXRDY/DMA activation condition*/
506 	sca_out(0x10, msci + TRC0, card); /* = TXRDY/DMA activation condition*/
507 	sca_out(0x14, msci + TRC1, card); /* +1=TXRDY/DMA deactiv condition */
508 
509 /* We're using the following interrupts:
510  * - TXINT (DMAC completed all transmisions, underrun or DCD change)
511  * - all DMA interrupts
512  */
513 	sca_set_carrier(port);
514 
515 	/* MSCI TX INT and RX INT A IRQ enable */
516 	sca_out(IE0_TXINT | IE0_RXINTA, msci + IE0, card);
517 	sca_out(IE1_UDRN | IE1_CDCD, msci + IE1, card);
518 	sca_out(sca_in(IER0, card) | (phy_node(port) ? 0xC0 : 0x0C),
519 		IER0, card); /* TXINT and RXINT */
520 	/* enable DMA IRQ */
521 	sca_out(sca_in(IER1, card) | (phy_node(port) ? 0xF0 : 0x0F),
522 		IER1, card);
523 
524 	sca_out(port->tmc, msci + TMC, card); /* Restore registers */
525 	sca_out(port->rxs, msci + RXS, card);
526 	sca_out(port->txs, msci + TXS, card);
527 	sca_out(CMD_TX_ENABLE, msci + CMD, card);
528 	sca_out(CMD_RX_ENABLE, msci + CMD, card);
529 
530 	netif_start_queue(dev);
531 }
532 
533 static void sca_close(struct net_device *dev)
534 {
535 	port_t *port = dev_to_port(dev);
536 	card_t *card = port_to_card(port);
537 
538 	/* reset channel */
539 	sca_out(CMD_RESET, get_msci(port) + CMD, port_to_card(port));
540 	/* disable MSCI interrupts */
541 	sca_out(sca_in(IER0, card) & (phy_node(port) ? 0x0F : 0xF0),
542 		IER0, card);
543 	/* disable DMA interrupts */
544 	sca_out(sca_in(IER1, card) & (phy_node(port) ? 0x0F : 0xF0),
545 		IER1, card);
546 
547 	netif_stop_queue(dev);
548 }
549 
550 static int sca_attach(struct net_device *dev, unsigned short encoding,
551 		      unsigned short parity)
552 {
553 	if (encoding != ENCODING_NRZ &&
554 	    encoding != ENCODING_NRZI &&
555 	    encoding != ENCODING_FM_MARK &&
556 	    encoding != ENCODING_FM_SPACE &&
557 	    encoding != ENCODING_MANCHESTER)
558 		return -EINVAL;
559 
560 	if (parity != PARITY_NONE &&
561 	    parity != PARITY_CRC16_PR0 &&
562 	    parity != PARITY_CRC16_PR1 &&
563 	    parity != PARITY_CRC16_PR0_CCITT &&
564 	    parity != PARITY_CRC16_PR1_CCITT)
565 		return -EINVAL;
566 
567 	dev_to_port(dev)->encoding = encoding;
568 	dev_to_port(dev)->parity = parity;
569 	return 0;
570 }
571 
572 #ifdef DEBUG_RINGS
573 static void sca_dump_rings(struct net_device *dev)
574 {
575 	port_t *port = dev_to_port(dev);
576 	card_t *card = port_to_card(port);
577 	u16 cnt;
578 #ifndef PAGE0_ALWAYS_MAPPED
579 	u8 page = sca_get_page(card);
580 
581 	openwin(card, 0);
582 #endif
583 
584 	printk(KERN_DEBUG "RX ring: CDA=%u EDA=%u DSR=%02X in=%u %sactive",
585 	       sca_inw(get_dmac_rx(port) + CDAL, card),
586 	       sca_inw(get_dmac_rx(port) + EDAL, card),
587 	       sca_in(DSR_RX(phy_node(port)), card), port->rxin,
588 	       sca_in(DSR_RX(phy_node(port)), card) & DSR_DE ? "" : "in");
589 	for (cnt = 0; cnt < port_to_card(port)->rx_ring_buffers; cnt++)
590 		pr_cont(" %02X", readb(&(desc_address(port, cnt, 0)->stat)));
591 	pr_cont("\n");
592 
593 	printk(KERN_DEBUG "TX ring: CDA=%u EDA=%u DSR=%02X in=%u "
594 	       "last=%u %sactive",
595 	       sca_inw(get_dmac_tx(port) + CDAL, card),
596 	       sca_inw(get_dmac_tx(port) + EDAL, card),
597 	       sca_in(DSR_TX(phy_node(port)), card), port->txin, port->txlast,
598 	       sca_in(DSR_TX(phy_node(port)), card) & DSR_DE ? "" : "in");
599 
600 	for (cnt = 0; cnt < port_to_card(port)->tx_ring_buffers; cnt++)
601 		pr_cont(" %02X", readb(&(desc_address(port, cnt, 1)->stat)));
602 	pr_cont("\n");
603 
604 	printk(KERN_DEBUG "MSCI: MD: %02x %02x %02x, ST: %02x %02x %02x %02x,"
605 	       " FST: %02x CST: %02x %02x\n",
606 	       sca_in(get_msci(port) + MD0, card),
607 	       sca_in(get_msci(port) + MD1, card),
608 	       sca_in(get_msci(port) + MD2, card),
609 	       sca_in(get_msci(port) + ST0, card),
610 	       sca_in(get_msci(port) + ST1, card),
611 	       sca_in(get_msci(port) + ST2, card),
612 	       sca_in(get_msci(port) + ST3, card),
613 	       sca_in(get_msci(port) + FST, card),
614 	       sca_in(get_msci(port) + CST0, card),
615 	       sca_in(get_msci(port) + CST1, card));
616 
617 	printk(KERN_DEBUG "ISR: %02x %02x %02x\n", sca_in(ISR0, card),
618 	       sca_in(ISR1, card), sca_in(ISR2, card));
619 
620 #ifndef PAGE0_ALWAYS_MAPPED
621 	openwin(card, page); /* Restore original page */
622 #endif
623 }
624 #endif /* DEBUG_RINGS */
625 
626 static netdev_tx_t sca_xmit(struct sk_buff *skb, struct net_device *dev)
627 {
628 	port_t *port = dev_to_port(dev);
629 	card_t *card = port_to_card(port);
630 	pkt_desc __iomem *desc;
631 	u32 buff, len;
632 	u8 page;
633 	u32 maxlen;
634 
635 	spin_lock_irq(&port->lock);
636 
637 	desc = desc_address(port, port->txin + 1, 1);
638 	BUG_ON(readb(&desc->stat)); /* previous xmit should stop queue */
639 
640 #ifdef DEBUG_PKT
641 	printk(KERN_DEBUG "%s TX(%i):", dev->name, skb->len);
642 	debug_frame(skb);
643 #endif
644 
645 	desc = desc_address(port, port->txin, 1);
646 	buff = buffer_offset(port, port->txin, 1);
647 	len = skb->len;
648 	page = buff / winsize(card);
649 	buff = buff % winsize(card);
650 	maxlen = winsize(card) - buff;
651 
652 	openwin(card, page);
653 	if (len > maxlen) {
654 		memcpy_toio(winbase(card) + buff, skb->data, maxlen);
655 		openwin(card, page + 1);
656 		memcpy_toio(winbase(card), skb->data + maxlen, len - maxlen);
657 	} else {
658 		memcpy_toio(winbase(card) + buff, skb->data, len);
659 	}
660 
661 #ifndef PAGE0_ALWAYS_MAPPED
662 	openwin(card, 0);	/* select pkt_desc table page back */
663 #endif
664 	writew(len, &desc->len);
665 	writeb(ST_TX_EOM, &desc->stat);
666 
667 	port->txin = next_desc(port, port->txin, 1);
668 	sca_outw(desc_offset(port, port->txin, 1),
669 		 get_dmac_tx(port) + EDAL, card);
670 
671 	sca_out(DSR_DE, DSR_TX(phy_node(port)), card); /* Enable TX DMA */
672 
673 	desc = desc_address(port, port->txin + 1, 1);
674 	if (readb(&desc->stat)) /* allow 1 packet gap */
675 		netif_stop_queue(dev);
676 
677 	spin_unlock_irq(&port->lock);
678 
679 	dev_kfree_skb(skb);
680 	return NETDEV_TX_OK;
681 }
682 
683 #ifdef NEED_DETECT_RAM
684 static u32 sca_detect_ram(card_t *card, u8 __iomem *rambase, u32 ramsize)
685 {
686 	/* Round RAM size to 32 bits, fill from end to start */
687 	u32 i = ramsize &= ~3;
688 	u32 size = winsize(card);
689 
690 	openwin(card, (i - 4) / size); /* select last window */
691 
692 	do {
693 		i -= 4;
694 		if ((i + 4) % size == 0)
695 			openwin(card, i / size);
696 		writel(i ^ 0x12345678, rambase + i % size);
697 	} while (i > 0);
698 
699 	for (i = 0; i < ramsize ; i += 4) {
700 		if (i % size == 0)
701 			openwin(card, i / size);
702 
703 		if (readl(rambase + i % size) != (i ^ 0x12345678))
704 			break;
705 	}
706 
707 	return i;
708 }
709 #endif /* NEED_DETECT_RAM */
710 
711 static void sca_init(card_t *card, int wait_states)
712 {
713 	sca_out(wait_states, WCRL, card); /* Wait Control */
714 	sca_out(wait_states, WCRM, card);
715 	sca_out(wait_states, WCRH, card);
716 
717 	sca_out(0, DMER, card);	/* DMA Master disable */
718 	sca_out(0x03, PCR, card); /* DMA priority */
719 	sca_out(0, DSR_RX(0), card); /* DMA disable - to halt state */
720 	sca_out(0, DSR_TX(0), card);
721 	sca_out(0, DSR_RX(1), card);
722 	sca_out(0, DSR_TX(1), card);
723 	sca_out(DMER_DME, DMER, card); /* DMA Master enable */
724 }
725