xref: /openbmc/linux/drivers/net/wan/hd64570.c (revision 6d99a79c)
1 /*
2  * Hitachi SCA HD64570 driver for Linux
3  *
4  * Copyright (C) 1998-2003 Krzysztof Halasa <khc@pm.waw.pl>
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of version 2 of the GNU General Public License
8  * as published by the Free Software Foundation.
9  *
10  * Source of information: Hitachi HD64570 SCA User's Manual
11  *
12  * We use the following SCA memory map:
13  *
14  * Packet buffer descriptor rings - starting from winbase or win0base:
15  * rx_ring_buffers * sizeof(pkt_desc) = logical channel #0 RX ring
16  * tx_ring_buffers * sizeof(pkt_desc) = logical channel #0 TX ring
17  * rx_ring_buffers * sizeof(pkt_desc) = logical channel #1 RX ring (if used)
18  * tx_ring_buffers * sizeof(pkt_desc) = logical channel #1 TX ring (if used)
19  *
20  * Packet data buffers - starting from winbase + buff_offset:
21  * rx_ring_buffers * HDLC_MAX_MRU     = logical channel #0 RX buffers
22  * tx_ring_buffers * HDLC_MAX_MRU     = logical channel #0 TX buffers
23  * rx_ring_buffers * HDLC_MAX_MRU     = logical channel #0 RX buffers (if used)
24  * tx_ring_buffers * HDLC_MAX_MRU     = logical channel #0 TX buffers (if used)
25  */
26 
27 #include <linux/bitops.h>
28 #include <linux/errno.h>
29 #include <linux/fcntl.h>
30 #include <linux/hdlc.h>
31 #include <linux/in.h>
32 #include <linux/interrupt.h>
33 #include <linux/ioport.h>
34 #include <linux/jiffies.h>
35 #include <linux/kernel.h>
36 #include <linux/module.h>
37 #include <linux/netdevice.h>
38 #include <linux/skbuff.h>
39 #include <linux/string.h>
40 #include <linux/types.h>
41 #include <asm/io.h>
42 #include <linux/uaccess.h>
43 #include "hd64570.h"
44 
45 #define get_msci(port)	  (phy_node(port) ?   MSCI1_OFFSET :   MSCI0_OFFSET)
46 #define get_dmac_rx(port) (phy_node(port) ? DMAC1RX_OFFSET : DMAC0RX_OFFSET)
47 #define get_dmac_tx(port) (phy_node(port) ? DMAC1TX_OFFSET : DMAC0TX_OFFSET)
48 
49 #define SCA_INTR_MSCI(node)    (node ? 0x10 : 0x01)
50 #define SCA_INTR_DMAC_RX(node) (node ? 0x20 : 0x02)
51 #define SCA_INTR_DMAC_TX(node) (node ? 0x40 : 0x04)
52 
53 
54 static inline struct net_device *port_to_dev(port_t *port)
55 {
56 	return port->dev;
57 }
58 
59 static inline int sca_intr_status(card_t *card)
60 {
61 	u8 result = 0;
62 	u8 isr0 = sca_in(ISR0, card);
63 	u8 isr1 = sca_in(ISR1, card);
64 
65 	if (isr1 & 0x03) result |= SCA_INTR_DMAC_RX(0);
66 	if (isr1 & 0x0C) result |= SCA_INTR_DMAC_TX(0);
67 	if (isr1 & 0x30) result |= SCA_INTR_DMAC_RX(1);
68 	if (isr1 & 0xC0) result |= SCA_INTR_DMAC_TX(1);
69 	if (isr0 & 0x0F) result |= SCA_INTR_MSCI(0);
70 	if (isr0 & 0xF0) result |= SCA_INTR_MSCI(1);
71 
72 	if (!(result & SCA_INTR_DMAC_TX(0)))
73 		if (sca_in(DSR_TX(0), card) & DSR_EOM)
74 			result |= SCA_INTR_DMAC_TX(0);
75 	if (!(result & SCA_INTR_DMAC_TX(1)))
76 		if (sca_in(DSR_TX(1), card) & DSR_EOM)
77 			result |= SCA_INTR_DMAC_TX(1);
78 
79 	return result;
80 }
81 
82 static inline port_t* dev_to_port(struct net_device *dev)
83 {
84 	return dev_to_hdlc(dev)->priv;
85 }
86 
87 static inline u16 next_desc(port_t *port, u16 desc, int transmit)
88 {
89 	return (desc + 1) % (transmit ? port_to_card(port)->tx_ring_buffers
90 			     : port_to_card(port)->rx_ring_buffers);
91 }
92 
93 
94 static inline u16 desc_abs_number(port_t *port, u16 desc, int transmit)
95 {
96 	u16 rx_buffs = port_to_card(port)->rx_ring_buffers;
97 	u16 tx_buffs = port_to_card(port)->tx_ring_buffers;
98 
99 	desc %= (transmit ? tx_buffs : rx_buffs); // called with "X + 1" etc.
100 	return log_node(port) * (rx_buffs + tx_buffs) +
101 		transmit * rx_buffs + desc;
102 }
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 
112 static inline pkt_desc __iomem *desc_address(port_t *port, u16 desc,
113 					     int transmit)
114 {
115 #ifdef PAGE0_ALWAYS_MAPPED
116 	return (pkt_desc __iomem *)(win0base(port_to_card(port))
117 				    + desc_offset(port, desc, transmit));
118 #else
119 	return (pkt_desc __iomem *)(winbase(port_to_card(port))
120 				    + desc_offset(port, desc, transmit));
121 #endif
122 }
123 
124 
125 static inline u32 buffer_offset(port_t *port, u16 desc, int transmit)
126 {
127 	return port_to_card(port)->buff_offset +
128 		desc_abs_number(port, desc, transmit) * (u32)HDLC_MAX_MRU;
129 }
130 
131 
132 static inline void sca_set_carrier(port_t *port)
133 {
134 	if (!(sca_in(get_msci(port) + ST3, port_to_card(port)) & ST3_DCD)) {
135 #ifdef DEBUG_LINK
136 		printk(KERN_DEBUG "%s: sca_set_carrier on\n",
137 		       port_to_dev(port)->name);
138 #endif
139 		netif_carrier_on(port_to_dev(port));
140 	} else {
141 #ifdef DEBUG_LINK
142 		printk(KERN_DEBUG "%s: sca_set_carrier off\n",
143 		       port_to_dev(port)->name);
144 #endif
145 		netif_carrier_off(port_to_dev(port));
146 	}
147 }
148 
149 
150 static void sca_init_port(port_t *port)
151 {
152 	card_t *card = port_to_card(port);
153 	int transmit, i;
154 
155 	port->rxin = 0;
156 	port->txin = 0;
157 	port->txlast = 0;
158 
159 #ifndef PAGE0_ALWAYS_MAPPED
160 	openwin(card, 0);
161 #endif
162 
163 	for (transmit = 0; transmit < 2; transmit++) {
164 		u16 dmac = transmit ? get_dmac_tx(port) : get_dmac_rx(port);
165 		u16 buffs = transmit ? card->tx_ring_buffers
166 			: card->rx_ring_buffers;
167 
168 		for (i = 0; i < buffs; i++) {
169 			pkt_desc __iomem *desc = desc_address(port, i, transmit);
170 			u16 chain_off = desc_offset(port, i + 1, transmit);
171 			u32 buff_off = buffer_offset(port, i, transmit);
172 
173 			writew(chain_off, &desc->cp);
174 			writel(buff_off, &desc->bp);
175 			writew(0, &desc->len);
176 			writeb(0, &desc->stat);
177 		}
178 
179 		/* DMA disable - to halt state */
180 		sca_out(0, transmit ? DSR_TX(phy_node(port)) :
181 			DSR_RX(phy_node(port)), card);
182 		/* software ABORT - to initial state */
183 		sca_out(DCR_ABORT, transmit ? DCR_TX(phy_node(port)) :
184 			DCR_RX(phy_node(port)), card);
185 
186 		/* current desc addr */
187 		sca_out(0, dmac + CPB, card); /* pointer base */
188 		sca_outw(desc_offset(port, 0, transmit), dmac + CDAL, card);
189 		if (!transmit)
190 			sca_outw(desc_offset(port, buffs - 1, transmit),
191 				 dmac + EDAL, card);
192 		else
193 			sca_outw(desc_offset(port, 0, transmit), dmac + EDAL,
194 				 card);
195 
196 		/* clear frame end interrupt counter */
197 		sca_out(DCR_CLEAR_EOF, transmit ? DCR_TX(phy_node(port)) :
198 			DCR_RX(phy_node(port)), card);
199 
200 		if (!transmit) { /* Receive */
201 			/* set buffer length */
202 			sca_outw(HDLC_MAX_MRU, dmac + BFLL, card);
203 			/* Chain mode, Multi-frame */
204 			sca_out(0x14, DMR_RX(phy_node(port)), card);
205 			sca_out(DIR_EOME | DIR_BOFE, DIR_RX(phy_node(port)),
206 				card);
207 			/* DMA enable */
208 			sca_out(DSR_DE, DSR_RX(phy_node(port)), card);
209 		} else {	/* Transmit */
210 			/* Chain mode, Multi-frame */
211 			sca_out(0x14, DMR_TX(phy_node(port)), card);
212 			/* enable underflow interrupts */
213 			sca_out(DIR_BOFE, DIR_TX(phy_node(port)), card);
214 		}
215 	}
216 	sca_set_carrier(port);
217 }
218 
219 
220 #ifdef NEED_SCA_MSCI_INTR
221 /* MSCI interrupt service */
222 static inline void sca_msci_intr(port_t *port)
223 {
224 	u16 msci = get_msci(port);
225 	card_t* card = port_to_card(port);
226 	u8 stat = sca_in(msci + ST1, card); /* read MSCI ST1 status */
227 
228 	/* Reset MSCI TX underrun and CDCD status bit */
229 	sca_out(stat & (ST1_UDRN | ST1_CDCD), msci + ST1, card);
230 
231 	if (stat & ST1_UDRN) {
232 		/* TX Underrun error detected */
233 		port_to_dev(port)->stats.tx_errors++;
234 		port_to_dev(port)->stats.tx_fifo_errors++;
235 	}
236 
237 	if (stat & ST1_CDCD)
238 		sca_set_carrier(port);
239 }
240 #endif
241 
242 
243 static inline void sca_rx(card_t *card, port_t *port, pkt_desc __iomem *desc,
244 			  u16 rxin)
245 {
246 	struct net_device *dev = port_to_dev(port);
247 	struct sk_buff *skb;
248 	u16 len;
249 	u32 buff;
250 	u32 maxlen;
251 	u8 page;
252 
253 	len = readw(&desc->len);
254 	skb = dev_alloc_skb(len);
255 	if (!skb) {
256 		dev->stats.rx_dropped++;
257 		return;
258 	}
259 
260 	buff = buffer_offset(port, rxin, 0);
261 	page = buff / winsize(card);
262 	buff = buff % winsize(card);
263 	maxlen = winsize(card) - buff;
264 
265 	openwin(card, page);
266 
267 	if (len > maxlen) {
268 		memcpy_fromio(skb->data, winbase(card) + buff, maxlen);
269 		openwin(card, page + 1);
270 		memcpy_fromio(skb->data + maxlen, winbase(card), len - maxlen);
271 	} else
272 		memcpy_fromio(skb->data, winbase(card) + buff, len);
273 
274 #ifndef PAGE0_ALWAYS_MAPPED
275 	openwin(card, 0);	/* select pkt_desc table page back */
276 #endif
277 	skb_put(skb, len);
278 #ifdef DEBUG_PKT
279 	printk(KERN_DEBUG "%s RX(%i):", dev->name, skb->len);
280 	debug_frame(skb);
281 #endif
282 	dev->stats.rx_packets++;
283 	dev->stats.rx_bytes += skb->len;
284 	skb->protocol = hdlc_type_trans(skb, dev);
285 	netif_rx(skb);
286 }
287 
288 
289 /* Receive DMA interrupt service */
290 static inline void sca_rx_intr(port_t *port)
291 {
292 	struct net_device *dev = port_to_dev(port);
293 	u16 dmac = get_dmac_rx(port);
294 	card_t *card = port_to_card(port);
295 	u8 stat = sca_in(DSR_RX(phy_node(port)), card); /* read DMA Status */
296 
297 	/* Reset DSR status bits */
298 	sca_out((stat & (DSR_EOT | DSR_EOM | DSR_BOF | DSR_COF)) | DSR_DWE,
299 		DSR_RX(phy_node(port)), card);
300 
301 	if (stat & DSR_BOF)
302 		/* Dropped one or more frames */
303 		dev->stats.rx_over_errors++;
304 
305 	while (1) {
306 		u32 desc_off = desc_offset(port, port->rxin, 0);
307 		pkt_desc __iomem *desc;
308 		u32 cda = sca_inw(dmac + CDAL, card);
309 
310 		if ((cda >= desc_off) && (cda < desc_off + sizeof(pkt_desc)))
311 			break;	/* No frame received */
312 
313 		desc = desc_address(port, port->rxin, 0);
314 		stat = readb(&desc->stat);
315 		if (!(stat & ST_RX_EOM))
316 			port->rxpart = 1; /* partial frame received */
317 		else if ((stat & ST_ERROR_MASK) || port->rxpart) {
318 			dev->stats.rx_errors++;
319 			if (stat & ST_RX_OVERRUN)
320 				dev->stats.rx_fifo_errors++;
321 			else if ((stat & (ST_RX_SHORT | ST_RX_ABORT |
322 					  ST_RX_RESBIT)) || port->rxpart)
323 				dev->stats.rx_frame_errors++;
324 			else if (stat & ST_RX_CRC)
325 				dev->stats.rx_crc_errors++;
326 			if (stat & ST_RX_EOM)
327 				port->rxpart = 0; /* received last fragment */
328 		} else
329 			sca_rx(card, port, desc, port->rxin);
330 
331 		/* Set new error descriptor address */
332 		sca_outw(desc_off, dmac + EDAL, card);
333 		port->rxin = next_desc(port, port->rxin, 0);
334 	}
335 
336 	/* make sure RX DMA is enabled */
337 	sca_out(DSR_DE, DSR_RX(phy_node(port)), card);
338 }
339 
340 
341 /* Transmit DMA interrupt service */
342 static inline void sca_tx_intr(port_t *port)
343 {
344 	struct net_device *dev = port_to_dev(port);
345 	u16 dmac = get_dmac_tx(port);
346 	card_t* card = port_to_card(port);
347 	u8 stat;
348 
349 	spin_lock(&port->lock);
350 
351 	stat = sca_in(DSR_TX(phy_node(port)), card); /* read DMA Status */
352 
353 	/* Reset DSR status bits */
354 	sca_out((stat & (DSR_EOT | DSR_EOM | DSR_BOF | DSR_COF)) | DSR_DWE,
355 		DSR_TX(phy_node(port)), card);
356 
357 	while (1) {
358 		pkt_desc __iomem *desc;
359 
360 		u32 desc_off = desc_offset(port, port->txlast, 1);
361 		u32 cda = sca_inw(dmac + CDAL, card);
362 		if ((cda >= desc_off) && (cda < desc_off + sizeof(pkt_desc)))
363 			break;	/* Transmitter is/will_be sending this frame */
364 
365 		desc = desc_address(port, port->txlast, 1);
366 		dev->stats.tx_packets++;
367 		dev->stats.tx_bytes += readw(&desc->len);
368 		writeb(0, &desc->stat);	/* Free descriptor */
369 		port->txlast = next_desc(port, port->txlast, 1);
370 	}
371 
372 	netif_wake_queue(dev);
373 	spin_unlock(&port->lock);
374 }
375 
376 
377 static irqreturn_t sca_intr(int irq, void* dev_id)
378 {
379 	card_t *card = dev_id;
380 	int i;
381 	u8 stat;
382 	int handled = 0;
383 	u8 page = sca_get_page(card);
384 
385 	while((stat = sca_intr_status(card)) != 0) {
386 		handled = 1;
387 		for (i = 0; i < 2; i++) {
388 			port_t *port = get_port(card, i);
389 			if (port) {
390 				if (stat & SCA_INTR_MSCI(i))
391 					sca_msci_intr(port);
392 
393 				if (stat & SCA_INTR_DMAC_RX(i))
394 					sca_rx_intr(port);
395 
396 				if (stat & SCA_INTR_DMAC_TX(i))
397 					sca_tx_intr(port);
398 			}
399 		}
400 	}
401 
402 	openwin(card, page);		/* Restore original page */
403 	return IRQ_RETVAL(handled);
404 }
405 
406 
407 static void sca_set_port(port_t *port)
408 {
409 	card_t* card = port_to_card(port);
410 	u16 msci = get_msci(port);
411 	u8 md2 = sca_in(msci + MD2, card);
412 	unsigned int tmc, br = 10, brv = 1024;
413 
414 
415 	if (port->settings.clock_rate > 0) {
416 		/* Try lower br for better accuracy*/
417 		do {
418 			br--;
419 			brv >>= 1; /* brv = 2^9 = 512 max in specs */
420 
421 			/* Baud Rate = CLOCK_BASE / TMC / 2^BR */
422 			tmc = CLOCK_BASE / brv / port->settings.clock_rate;
423 		}while (br > 1 && tmc <= 128);
424 
425 		if (tmc < 1) {
426 			tmc = 1;
427 			br = 0;	/* For baud=CLOCK_BASE we use tmc=1 br=0 */
428 			brv = 1;
429 		} else if (tmc > 255)
430 			tmc = 256; /* tmc=0 means 256 - low baud rates */
431 
432 		port->settings.clock_rate = CLOCK_BASE / brv / tmc;
433 	} else {
434 		br = 9; /* Minimum clock rate */
435 		tmc = 256;	/* 8bit = 0 */
436 		port->settings.clock_rate = CLOCK_BASE / (256 * 512);
437 	}
438 
439 	port->rxs = (port->rxs & ~CLK_BRG_MASK) | br;
440 	port->txs = (port->txs & ~CLK_BRG_MASK) | br;
441 	port->tmc = tmc;
442 
443 	/* baud divisor - time constant*/
444 	sca_out(port->tmc, msci + TMC, card);
445 
446 	/* Set BRG bits */
447 	sca_out(port->rxs, msci + RXS, card);
448 	sca_out(port->txs, msci + TXS, card);
449 
450 	if (port->settings.loopback)
451 		md2 |= MD2_LOOPBACK;
452 	else
453 		md2 &= ~MD2_LOOPBACK;
454 
455 	sca_out(md2, msci + MD2, card);
456 
457 }
458 
459 
460 static void sca_open(struct net_device *dev)
461 {
462 	port_t *port = dev_to_port(dev);
463 	card_t* card = port_to_card(port);
464 	u16 msci = get_msci(port);
465 	u8 md0, md2;
466 
467 	switch(port->encoding) {
468 	case ENCODING_NRZ:	md2 = MD2_NRZ;		break;
469 	case ENCODING_NRZI:	md2 = MD2_NRZI;		break;
470 	case ENCODING_FM_MARK:	md2 = MD2_FM_MARK;	break;
471 	case ENCODING_FM_SPACE:	md2 = MD2_FM_SPACE;	break;
472 	default:		md2 = MD2_MANCHESTER;
473 	}
474 
475 	if (port->settings.loopback)
476 		md2 |= MD2_LOOPBACK;
477 
478 	switch(port->parity) {
479 	case PARITY_CRC16_PR0:	     md0 = MD0_HDLC | MD0_CRC_16_0;  break;
480 	case PARITY_CRC16_PR1:	     md0 = MD0_HDLC | MD0_CRC_16;    break;
481 	case PARITY_CRC16_PR0_CCITT: md0 = MD0_HDLC | MD0_CRC_ITU_0; break;
482 	case PARITY_CRC16_PR1_CCITT: md0 = MD0_HDLC | MD0_CRC_ITU;   break;
483 	default:		     md0 = MD0_HDLC | MD0_CRC_NONE;
484 	}
485 
486 	sca_out(CMD_RESET, msci + CMD, card);
487 	sca_out(md0, msci + MD0, card);
488 	sca_out(0x00, msci + MD1, card); /* no address field check */
489 	sca_out(md2, msci + MD2, card);
490 	sca_out(0x7E, msci + IDL, card); /* flag character 0x7E */
491 	sca_out(CTL_IDLE, msci + CTL, card);
492 
493 	/* Allow at least 8 bytes before requesting RX DMA operation */
494 	/* TX with higher priority and possibly with shorter transfers */
495 	sca_out(0x07, msci + RRC, card); /* +1=RXRDY/DMA activation condition*/
496 	sca_out(0x10, msci + TRC0, card); /* = TXRDY/DMA activation condition*/
497 	sca_out(0x14, msci + TRC1, card); /* +1=TXRDY/DMA deactiv condition */
498 
499 /* We're using the following interrupts:
500    - TXINT (DMAC completed all transmisions, underrun or DCD change)
501    - all DMA interrupts
502 */
503 	sca_set_carrier(port);
504 
505 	/* MSCI TX INT and RX INT A IRQ enable */
506 	sca_out(IE0_TXINT | IE0_RXINTA, msci + IE0, card);
507 	sca_out(IE1_UDRN | IE1_CDCD, msci + IE1, card);
508 	sca_out(sca_in(IER0, card) | (phy_node(port) ? 0xC0 : 0x0C),
509 		IER0, card); /* TXINT and RXINT */
510 	/* enable DMA IRQ */
511 	sca_out(sca_in(IER1, card) | (phy_node(port) ? 0xF0 : 0x0F),
512 		IER1, card);
513 
514 	sca_out(port->tmc, msci + TMC, card); /* Restore registers */
515 	sca_out(port->rxs, msci + RXS, card);
516 	sca_out(port->txs, msci + TXS, card);
517 	sca_out(CMD_TX_ENABLE, msci + CMD, card);
518 	sca_out(CMD_RX_ENABLE, msci + CMD, card);
519 
520 	netif_start_queue(dev);
521 }
522 
523 
524 static void sca_close(struct net_device *dev)
525 {
526 	port_t *port = dev_to_port(dev);
527 	card_t* card = port_to_card(port);
528 
529 	/* reset channel */
530 	sca_out(CMD_RESET, get_msci(port) + CMD, port_to_card(port));
531 	/* disable MSCI interrupts */
532 	sca_out(sca_in(IER0, card) & (phy_node(port) ? 0x0F : 0xF0),
533 		IER0, card);
534 	/* disable DMA interrupts */
535 	sca_out(sca_in(IER1, card) & (phy_node(port) ? 0x0F : 0xF0),
536 		IER1, card);
537 
538 	netif_stop_queue(dev);
539 }
540 
541 
542 static int sca_attach(struct net_device *dev, unsigned short encoding,
543 		      unsigned short parity)
544 {
545 	if (encoding != ENCODING_NRZ &&
546 	    encoding != ENCODING_NRZI &&
547 	    encoding != ENCODING_FM_MARK &&
548 	    encoding != ENCODING_FM_SPACE &&
549 	    encoding != ENCODING_MANCHESTER)
550 		return -EINVAL;
551 
552 	if (parity != PARITY_NONE &&
553 	    parity != PARITY_CRC16_PR0 &&
554 	    parity != PARITY_CRC16_PR1 &&
555 	    parity != PARITY_CRC16_PR0_CCITT &&
556 	    parity != PARITY_CRC16_PR1_CCITT)
557 		return -EINVAL;
558 
559 	dev_to_port(dev)->encoding = encoding;
560 	dev_to_port(dev)->parity = parity;
561 	return 0;
562 }
563 
564 
565 #ifdef DEBUG_RINGS
566 static void sca_dump_rings(struct net_device *dev)
567 {
568 	port_t *port = dev_to_port(dev);
569 	card_t *card = port_to_card(port);
570 	u16 cnt;
571 #ifndef PAGE0_ALWAYS_MAPPED
572 	u8 page = sca_get_page(card);
573 
574 	openwin(card, 0);
575 #endif
576 
577 	printk(KERN_DEBUG "RX ring: CDA=%u EDA=%u DSR=%02X in=%u %sactive",
578 	       sca_inw(get_dmac_rx(port) + CDAL, card),
579 	       sca_inw(get_dmac_rx(port) + EDAL, card),
580 	       sca_in(DSR_RX(phy_node(port)), card), port->rxin,
581 	       sca_in(DSR_RX(phy_node(port)), card) & DSR_DE ? "" : "in");
582 	for (cnt = 0; cnt < port_to_card(port)->rx_ring_buffers; cnt++)
583 		pr_cont(" %02X", readb(&(desc_address(port, cnt, 0)->stat)));
584 	pr_cont("\n");
585 
586 	printk(KERN_DEBUG "TX ring: CDA=%u EDA=%u DSR=%02X in=%u "
587 	       "last=%u %sactive",
588 	       sca_inw(get_dmac_tx(port) + CDAL, card),
589 	       sca_inw(get_dmac_tx(port) + EDAL, card),
590 	       sca_in(DSR_TX(phy_node(port)), card), port->txin, port->txlast,
591 	       sca_in(DSR_TX(phy_node(port)), card) & DSR_DE ? "" : "in");
592 
593 	for (cnt = 0; cnt < port_to_card(port)->tx_ring_buffers; cnt++)
594 		pr_cont(" %02X", readb(&(desc_address(port, cnt, 1)->stat)));
595 	pr_cont("\n");
596 
597 	printk(KERN_DEBUG "MSCI: MD: %02x %02x %02x, ST: %02x %02x %02x %02x,"
598 	       " FST: %02x CST: %02x %02x\n",
599 	       sca_in(get_msci(port) + MD0, card),
600 	       sca_in(get_msci(port) + MD1, card),
601 	       sca_in(get_msci(port) + MD2, card),
602 	       sca_in(get_msci(port) + ST0, card),
603 	       sca_in(get_msci(port) + ST1, card),
604 	       sca_in(get_msci(port) + ST2, card),
605 	       sca_in(get_msci(port) + ST3, card),
606 	       sca_in(get_msci(port) + FST, card),
607 	       sca_in(get_msci(port) + CST0, card),
608 	       sca_in(get_msci(port) + CST1, card));
609 
610 	printk(KERN_DEBUG "ISR: %02x %02x %02x\n", sca_in(ISR0, card),
611 	       sca_in(ISR1, card), sca_in(ISR2, card));
612 
613 #ifndef PAGE0_ALWAYS_MAPPED
614 	openwin(card, page); /* Restore original page */
615 #endif
616 }
617 #endif /* DEBUG_RINGS */
618 
619 
620 static netdev_tx_t sca_xmit(struct sk_buff *skb, struct net_device *dev)
621 {
622 	port_t *port = dev_to_port(dev);
623 	card_t *card = port_to_card(port);
624 	pkt_desc __iomem *desc;
625 	u32 buff, len;
626 	u8 page;
627 	u32 maxlen;
628 
629 	spin_lock_irq(&port->lock);
630 
631 	desc = desc_address(port, port->txin + 1, 1);
632 	BUG_ON(readb(&desc->stat)); /* previous xmit should stop queue */
633 
634 #ifdef DEBUG_PKT
635 	printk(KERN_DEBUG "%s TX(%i):", dev->name, skb->len);
636 	debug_frame(skb);
637 #endif
638 
639 	desc = desc_address(port, port->txin, 1);
640 	buff = buffer_offset(port, port->txin, 1);
641 	len = skb->len;
642 	page = buff / winsize(card);
643 	buff = buff % winsize(card);
644 	maxlen = winsize(card) - buff;
645 
646 	openwin(card, page);
647 	if (len > maxlen) {
648 		memcpy_toio(winbase(card) + buff, skb->data, maxlen);
649 		openwin(card, page + 1);
650 		memcpy_toio(winbase(card), skb->data + maxlen, len - maxlen);
651 	} else
652 		memcpy_toio(winbase(card) + buff, skb->data, len);
653 
654 #ifndef PAGE0_ALWAYS_MAPPED
655 	openwin(card, 0);	/* select pkt_desc table page back */
656 #endif
657 	writew(len, &desc->len);
658 	writeb(ST_TX_EOM, &desc->stat);
659 
660 	port->txin = next_desc(port, port->txin, 1);
661 	sca_outw(desc_offset(port, port->txin, 1),
662 		 get_dmac_tx(port) + EDAL, card);
663 
664 	sca_out(DSR_DE, DSR_TX(phy_node(port)), card); /* Enable TX DMA */
665 
666 	desc = desc_address(port, port->txin + 1, 1);
667 	if (readb(&desc->stat)) /* allow 1 packet gap */
668 		netif_stop_queue(dev);
669 
670 	spin_unlock_irq(&port->lock);
671 
672 	dev_kfree_skb(skb);
673 	return NETDEV_TX_OK;
674 }
675 
676 
677 #ifdef NEED_DETECT_RAM
678 static u32 sca_detect_ram(card_t *card, u8 __iomem *rambase, u32 ramsize)
679 {
680 	/* Round RAM size to 32 bits, fill from end to start */
681 	u32 i = ramsize &= ~3;
682 	u32 size = winsize(card);
683 
684 	openwin(card, (i - 4) / size); /* select last window */
685 
686 	do {
687 		i -= 4;
688 		if ((i + 4) % size == 0)
689 			openwin(card, i / size);
690 		writel(i ^ 0x12345678, rambase + i % size);
691 	} while (i > 0);
692 
693 	for (i = 0; i < ramsize ; i += 4) {
694 		if (i % size == 0)
695 			openwin(card, i / size);
696 
697 		if (readl(rambase + i % size) != (i ^ 0x12345678))
698 			break;
699 	}
700 
701 	return i;
702 }
703 #endif /* NEED_DETECT_RAM */
704 
705 
706 static void sca_init(card_t *card, int wait_states)
707 {
708 	sca_out(wait_states, WCRL, card); /* Wait Control */
709 	sca_out(wait_states, WCRM, card);
710 	sca_out(wait_states, WCRH, card);
711 
712 	sca_out(0, DMER, card);	/* DMA Master disable */
713 	sca_out(0x03, PCR, card); /* DMA priority */
714 	sca_out(0, DSR_RX(0), card); /* DMA disable - to halt state */
715 	sca_out(0, DSR_TX(0), card);
716 	sca_out(0, DSR_RX(1), card);
717 	sca_out(0, DSR_TX(1), card);
718 	sca_out(DMER_DME, DMER, card); /* DMA Master enable */
719 }
720