xref: /openbmc/linux/drivers/net/wan/hd64570.c (revision 8dde5715)
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 
51 static inline struct net_device *port_to_dev(port_t *port)
52 {
53 	return port->dev;
54 }
55 
56 static inline int sca_intr_status(card_t *card)
57 {
58 	u8 result = 0;
59 	u8 isr0 = sca_in(ISR0, card);
60 	u8 isr1 = sca_in(ISR1, card);
61 
62 	if (isr1 & 0x03) result |= SCA_INTR_DMAC_RX(0);
63 	if (isr1 & 0x0C) result |= SCA_INTR_DMAC_TX(0);
64 	if (isr1 & 0x30) result |= SCA_INTR_DMAC_RX(1);
65 	if (isr1 & 0xC0) result |= SCA_INTR_DMAC_TX(1);
66 	if (isr0 & 0x0F) result |= SCA_INTR_MSCI(0);
67 	if (isr0 & 0xF0) result |= SCA_INTR_MSCI(1);
68 
69 	if (!(result & SCA_INTR_DMAC_TX(0)))
70 		if (sca_in(DSR_TX(0), card) & DSR_EOM)
71 			result |= SCA_INTR_DMAC_TX(0);
72 	if (!(result & SCA_INTR_DMAC_TX(1)))
73 		if (sca_in(DSR_TX(1), card) & DSR_EOM)
74 			result |= SCA_INTR_DMAC_TX(1);
75 
76 	return result;
77 }
78 
79 static inline port_t* dev_to_port(struct net_device *dev)
80 {
81 	return dev_to_hdlc(dev)->priv;
82 }
83 
84 static inline u16 next_desc(port_t *port, u16 desc, int transmit)
85 {
86 	return (desc + 1) % (transmit ? port_to_card(port)->tx_ring_buffers
87 			     : port_to_card(port)->rx_ring_buffers);
88 }
89 
90 
91 static inline u16 desc_abs_number(port_t *port, u16 desc, int transmit)
92 {
93 	u16 rx_buffs = port_to_card(port)->rx_ring_buffers;
94 	u16 tx_buffs = port_to_card(port)->tx_ring_buffers;
95 
96 	desc %= (transmit ? tx_buffs : rx_buffs); // called with "X + 1" etc.
97 	return log_node(port) * (rx_buffs + tx_buffs) +
98 		transmit * rx_buffs + desc;
99 }
100 
101 
102 static inline u16 desc_offset(port_t *port, u16 desc, int transmit)
103 {
104 	/* Descriptor offset always fits in 16 bits */
105 	return desc_abs_number(port, desc, transmit) * sizeof(pkt_desc);
106 }
107 
108 
109 static inline pkt_desc __iomem *desc_address(port_t *port, u16 desc,
110 					     int transmit)
111 {
112 #ifdef PAGE0_ALWAYS_MAPPED
113 	return (pkt_desc __iomem *)(win0base(port_to_card(port))
114 				    + desc_offset(port, desc, transmit));
115 #else
116 	return (pkt_desc __iomem *)(winbase(port_to_card(port))
117 				    + desc_offset(port, desc, transmit));
118 #endif
119 }
120 
121 
122 static inline u32 buffer_offset(port_t *port, u16 desc, int transmit)
123 {
124 	return port_to_card(port)->buff_offset +
125 		desc_abs_number(port, desc, transmit) * (u32)HDLC_MAX_MRU;
126 }
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 
147 static void sca_init_port(port_t *port)
148 {
149 	card_t *card = port_to_card(port);
150 	int transmit, i;
151 
152 	port->rxin = 0;
153 	port->txin = 0;
154 	port->txlast = 0;
155 
156 #ifndef PAGE0_ALWAYS_MAPPED
157 	openwin(card, 0);
158 #endif
159 
160 	for (transmit = 0; transmit < 2; transmit++) {
161 		u16 dmac = transmit ? get_dmac_tx(port) : get_dmac_rx(port);
162 		u16 buffs = transmit ? card->tx_ring_buffers
163 			: card->rx_ring_buffers;
164 
165 		for (i = 0; i < buffs; i++) {
166 			pkt_desc __iomem *desc = desc_address(port, i, transmit);
167 			u16 chain_off = desc_offset(port, i + 1, transmit);
168 			u32 buff_off = buffer_offset(port, i, transmit);
169 
170 			writew(chain_off, &desc->cp);
171 			writel(buff_off, &desc->bp);
172 			writew(0, &desc->len);
173 			writeb(0, &desc->stat);
174 		}
175 
176 		/* DMA disable - to halt state */
177 		sca_out(0, transmit ? DSR_TX(phy_node(port)) :
178 			DSR_RX(phy_node(port)), card);
179 		/* software ABORT - to initial state */
180 		sca_out(DCR_ABORT, transmit ? DCR_TX(phy_node(port)) :
181 			DCR_RX(phy_node(port)), card);
182 
183 		/* current desc addr */
184 		sca_out(0, dmac + CPB, card); /* pointer base */
185 		sca_outw(desc_offset(port, 0, transmit), dmac + CDAL, card);
186 		if (!transmit)
187 			sca_outw(desc_offset(port, buffs - 1, transmit),
188 				 dmac + EDAL, card);
189 		else
190 			sca_outw(desc_offset(port, 0, transmit), dmac + EDAL,
191 				 card);
192 
193 		/* clear frame end interrupt counter */
194 		sca_out(DCR_CLEAR_EOF, transmit ? DCR_TX(phy_node(port)) :
195 			DCR_RX(phy_node(port)), card);
196 
197 		if (!transmit) { /* Receive */
198 			/* set buffer length */
199 			sca_outw(HDLC_MAX_MRU, dmac + BFLL, card);
200 			/* Chain mode, Multi-frame */
201 			sca_out(0x14, DMR_RX(phy_node(port)), card);
202 			sca_out(DIR_EOME | DIR_BOFE, DIR_RX(phy_node(port)),
203 				card);
204 			/* DMA enable */
205 			sca_out(DSR_DE, DSR_RX(phy_node(port)), card);
206 		} else {	/* Transmit */
207 			/* Chain mode, Multi-frame */
208 			sca_out(0x14, DMR_TX(phy_node(port)), card);
209 			/* enable underflow interrupts */
210 			sca_out(DIR_BOFE, DIR_TX(phy_node(port)), card);
211 		}
212 	}
213 	sca_set_carrier(port);
214 }
215 
216 
217 #ifdef NEED_SCA_MSCI_INTR
218 /* MSCI interrupt service */
219 static inline void sca_msci_intr(port_t *port)
220 {
221 	u16 msci = get_msci(port);
222 	card_t* card = port_to_card(port);
223 	u8 stat = sca_in(msci + ST1, card); /* read MSCI ST1 status */
224 
225 	/* Reset MSCI TX underrun and CDCD status bit */
226 	sca_out(stat & (ST1_UDRN | ST1_CDCD), msci + ST1, card);
227 
228 	if (stat & ST1_UDRN) {
229 		/* TX Underrun error detected */
230 		port_to_dev(port)->stats.tx_errors++;
231 		port_to_dev(port)->stats.tx_fifo_errors++;
232 	}
233 
234 	if (stat & ST1_CDCD)
235 		sca_set_carrier(port);
236 }
237 #endif
238 
239 
240 static inline void sca_rx(card_t *card, port_t *port, pkt_desc __iomem *desc,
241 			  u16 rxin)
242 {
243 	struct net_device *dev = port_to_dev(port);
244 	struct sk_buff *skb;
245 	u16 len;
246 	u32 buff;
247 	u32 maxlen;
248 	u8 page;
249 
250 	len = readw(&desc->len);
251 	skb = dev_alloc_skb(len);
252 	if (!skb) {
253 		dev->stats.rx_dropped++;
254 		return;
255 	}
256 
257 	buff = buffer_offset(port, rxin, 0);
258 	page = buff / winsize(card);
259 	buff = buff % winsize(card);
260 	maxlen = winsize(card) - buff;
261 
262 	openwin(card, page);
263 
264 	if (len > maxlen) {
265 		memcpy_fromio(skb->data, winbase(card) + buff, maxlen);
266 		openwin(card, page + 1);
267 		memcpy_fromio(skb->data + maxlen, winbase(card), len - maxlen);
268 	} else
269 		memcpy_fromio(skb->data, winbase(card) + buff, len);
270 
271 #ifndef PAGE0_ALWAYS_MAPPED
272 	openwin(card, 0);	/* select pkt_desc table page back */
273 #endif
274 	skb_put(skb, len);
275 #ifdef DEBUG_PKT
276 	printk(KERN_DEBUG "%s RX(%i):", dev->name, skb->len);
277 	debug_frame(skb);
278 #endif
279 	dev->stats.rx_packets++;
280 	dev->stats.rx_bytes += skb->len;
281 	skb->protocol = hdlc_type_trans(skb, dev);
282 	netif_rx(skb);
283 }
284 
285 
286 /* Receive DMA interrupt service */
287 static inline void sca_rx_intr(port_t *port)
288 {
289 	struct net_device *dev = port_to_dev(port);
290 	u16 dmac = get_dmac_rx(port);
291 	card_t *card = port_to_card(port);
292 	u8 stat = sca_in(DSR_RX(phy_node(port)), card); /* read DMA Status */
293 
294 	/* Reset DSR status bits */
295 	sca_out((stat & (DSR_EOT | DSR_EOM | DSR_BOF | DSR_COF)) | DSR_DWE,
296 		DSR_RX(phy_node(port)), card);
297 
298 	if (stat & DSR_BOF)
299 		/* Dropped one or more frames */
300 		dev->stats.rx_over_errors++;
301 
302 	while (1) {
303 		u32 desc_off = desc_offset(port, port->rxin, 0);
304 		pkt_desc __iomem *desc;
305 		u32 cda = sca_inw(dmac + CDAL, card);
306 
307 		if ((cda >= desc_off) && (cda < desc_off + sizeof(pkt_desc)))
308 			break;	/* No frame received */
309 
310 		desc = desc_address(port, port->rxin, 0);
311 		stat = readb(&desc->stat);
312 		if (!(stat & ST_RX_EOM))
313 			port->rxpart = 1; /* partial frame received */
314 		else if ((stat & ST_ERROR_MASK) || port->rxpart) {
315 			dev->stats.rx_errors++;
316 			if (stat & ST_RX_OVERRUN)
317 				dev->stats.rx_fifo_errors++;
318 			else if ((stat & (ST_RX_SHORT | ST_RX_ABORT |
319 					  ST_RX_RESBIT)) || port->rxpart)
320 				dev->stats.rx_frame_errors++;
321 			else if (stat & ST_RX_CRC)
322 				dev->stats.rx_crc_errors++;
323 			if (stat & ST_RX_EOM)
324 				port->rxpart = 0; /* received last fragment */
325 		} else
326 			sca_rx(card, port, desc, port->rxin);
327 
328 		/* Set new error descriptor address */
329 		sca_outw(desc_off, dmac + EDAL, card);
330 		port->rxin = next_desc(port, port->rxin, 0);
331 	}
332 
333 	/* make sure RX DMA is enabled */
334 	sca_out(DSR_DE, DSR_RX(phy_node(port)), card);
335 }
336 
337 
338 /* Transmit DMA interrupt service */
339 static inline void sca_tx_intr(port_t *port)
340 {
341 	struct net_device *dev = port_to_dev(port);
342 	u16 dmac = get_dmac_tx(port);
343 	card_t* card = port_to_card(port);
344 	u8 stat;
345 
346 	spin_lock(&port->lock);
347 
348 	stat = sca_in(DSR_TX(phy_node(port)), card); /* read DMA Status */
349 
350 	/* Reset DSR status bits */
351 	sca_out((stat & (DSR_EOT | DSR_EOM | DSR_BOF | DSR_COF)) | DSR_DWE,
352 		DSR_TX(phy_node(port)), card);
353 
354 	while (1) {
355 		pkt_desc __iomem *desc;
356 
357 		u32 desc_off = desc_offset(port, port->txlast, 1);
358 		u32 cda = sca_inw(dmac + CDAL, card);
359 		if ((cda >= desc_off) && (cda < desc_off + sizeof(pkt_desc)))
360 			break;	/* Transmitter is/will_be sending this frame */
361 
362 		desc = desc_address(port, port->txlast, 1);
363 		dev->stats.tx_packets++;
364 		dev->stats.tx_bytes += readw(&desc->len);
365 		writeb(0, &desc->stat);	/* Free descriptor */
366 		port->txlast = next_desc(port, port->txlast, 1);
367 	}
368 
369 	netif_wake_queue(dev);
370 	spin_unlock(&port->lock);
371 }
372 
373 
374 static irqreturn_t sca_intr(int irq, void* dev_id)
375 {
376 	card_t *card = dev_id;
377 	int i;
378 	u8 stat;
379 	int handled = 0;
380 	u8 page = sca_get_page(card);
381 
382 	while((stat = sca_intr_status(card)) != 0) {
383 		handled = 1;
384 		for (i = 0; i < 2; i++) {
385 			port_t *port = get_port(card, i);
386 			if (port) {
387 				if (stat & SCA_INTR_MSCI(i))
388 					sca_msci_intr(port);
389 
390 				if (stat & SCA_INTR_DMAC_RX(i))
391 					sca_rx_intr(port);
392 
393 				if (stat & SCA_INTR_DMAC_TX(i))
394 					sca_tx_intr(port);
395 			}
396 		}
397 	}
398 
399 	openwin(card, page);		/* Restore original page */
400 	return IRQ_RETVAL(handled);
401 }
402 
403 
404 static void sca_set_port(port_t *port)
405 {
406 	card_t* card = port_to_card(port);
407 	u16 msci = get_msci(port);
408 	u8 md2 = sca_in(msci + MD2, card);
409 	unsigned int tmc, br = 10, brv = 1024;
410 
411 
412 	if (port->settings.clock_rate > 0) {
413 		/* Try lower br for better accuracy*/
414 		do {
415 			br--;
416 			brv >>= 1; /* brv = 2^9 = 512 max in specs */
417 
418 			/* Baud Rate = CLOCK_BASE / TMC / 2^BR */
419 			tmc = CLOCK_BASE / brv / port->settings.clock_rate;
420 		}while (br > 1 && tmc <= 128);
421 
422 		if (tmc < 1) {
423 			tmc = 1;
424 			br = 0;	/* For baud=CLOCK_BASE we use tmc=1 br=0 */
425 			brv = 1;
426 		} else if (tmc > 255)
427 			tmc = 256; /* tmc=0 means 256 - low baud rates */
428 
429 		port->settings.clock_rate = CLOCK_BASE / brv / tmc;
430 	} else {
431 		br = 9; /* Minimum clock rate */
432 		tmc = 256;	/* 8bit = 0 */
433 		port->settings.clock_rate = CLOCK_BASE / (256 * 512);
434 	}
435 
436 	port->rxs = (port->rxs & ~CLK_BRG_MASK) | br;
437 	port->txs = (port->txs & ~CLK_BRG_MASK) | br;
438 	port->tmc = tmc;
439 
440 	/* baud divisor - time constant*/
441 	sca_out(port->tmc, msci + TMC, card);
442 
443 	/* Set BRG bits */
444 	sca_out(port->rxs, msci + RXS, card);
445 	sca_out(port->txs, msci + TXS, card);
446 
447 	if (port->settings.loopback)
448 		md2 |= MD2_LOOPBACK;
449 	else
450 		md2 &= ~MD2_LOOPBACK;
451 
452 	sca_out(md2, msci + MD2, card);
453 
454 }
455 
456 
457 static void sca_open(struct net_device *dev)
458 {
459 	port_t *port = dev_to_port(dev);
460 	card_t* card = port_to_card(port);
461 	u16 msci = get_msci(port);
462 	u8 md0, md2;
463 
464 	switch(port->encoding) {
465 	case ENCODING_NRZ:	md2 = MD2_NRZ;		break;
466 	case ENCODING_NRZI:	md2 = MD2_NRZI;		break;
467 	case ENCODING_FM_MARK:	md2 = MD2_FM_MARK;	break;
468 	case ENCODING_FM_SPACE:	md2 = MD2_FM_SPACE;	break;
469 	default:		md2 = MD2_MANCHESTER;
470 	}
471 
472 	if (port->settings.loopback)
473 		md2 |= MD2_LOOPBACK;
474 
475 	switch(port->parity) {
476 	case PARITY_CRC16_PR0:	     md0 = MD0_HDLC | MD0_CRC_16_0;  break;
477 	case PARITY_CRC16_PR1:	     md0 = MD0_HDLC | MD0_CRC_16;    break;
478 	case PARITY_CRC16_PR0_CCITT: md0 = MD0_HDLC | MD0_CRC_ITU_0; break;
479 	case PARITY_CRC16_PR1_CCITT: md0 = MD0_HDLC | MD0_CRC_ITU;   break;
480 	default:		     md0 = MD0_HDLC | MD0_CRC_NONE;
481 	}
482 
483 	sca_out(CMD_RESET, msci + CMD, card);
484 	sca_out(md0, msci + MD0, card);
485 	sca_out(0x00, msci + MD1, card); /* no address field check */
486 	sca_out(md2, msci + MD2, card);
487 	sca_out(0x7E, msci + IDL, card); /* flag character 0x7E */
488 	sca_out(CTL_IDLE, msci + CTL, card);
489 
490 	/* Allow at least 8 bytes before requesting RX DMA operation */
491 	/* TX with higher priority and possibly with shorter transfers */
492 	sca_out(0x07, msci + RRC, card); /* +1=RXRDY/DMA activation condition*/
493 	sca_out(0x10, msci + TRC0, card); /* = TXRDY/DMA activation condition*/
494 	sca_out(0x14, msci + TRC1, card); /* +1=TXRDY/DMA deactiv condition */
495 
496 /* We're using the following interrupts:
497    - TXINT (DMAC completed all transmisions, underrun or DCD change)
498    - all DMA interrupts
499 */
500 	sca_set_carrier(port);
501 
502 	/* MSCI TX INT and RX INT A IRQ enable */
503 	sca_out(IE0_TXINT | IE0_RXINTA, msci + IE0, card);
504 	sca_out(IE1_UDRN | IE1_CDCD, msci + IE1, card);
505 	sca_out(sca_in(IER0, card) | (phy_node(port) ? 0xC0 : 0x0C),
506 		IER0, card); /* TXINT and RXINT */
507 	/* enable DMA IRQ */
508 	sca_out(sca_in(IER1, card) | (phy_node(port) ? 0xF0 : 0x0F),
509 		IER1, card);
510 
511 	sca_out(port->tmc, msci + TMC, card); /* Restore registers */
512 	sca_out(port->rxs, msci + RXS, card);
513 	sca_out(port->txs, msci + TXS, card);
514 	sca_out(CMD_TX_ENABLE, msci + CMD, card);
515 	sca_out(CMD_RX_ENABLE, msci + CMD, card);
516 
517 	netif_start_queue(dev);
518 }
519 
520 
521 static void sca_close(struct net_device *dev)
522 {
523 	port_t *port = dev_to_port(dev);
524 	card_t* card = port_to_card(port);
525 
526 	/* reset channel */
527 	sca_out(CMD_RESET, get_msci(port) + CMD, port_to_card(port));
528 	/* disable MSCI interrupts */
529 	sca_out(sca_in(IER0, card) & (phy_node(port) ? 0x0F : 0xF0),
530 		IER0, card);
531 	/* disable DMA interrupts */
532 	sca_out(sca_in(IER1, card) & (phy_node(port) ? 0x0F : 0xF0),
533 		IER1, card);
534 
535 	netif_stop_queue(dev);
536 }
537 
538 
539 static int sca_attach(struct net_device *dev, unsigned short encoding,
540 		      unsigned short parity)
541 {
542 	if (encoding != ENCODING_NRZ &&
543 	    encoding != ENCODING_NRZI &&
544 	    encoding != ENCODING_FM_MARK &&
545 	    encoding != ENCODING_FM_SPACE &&
546 	    encoding != ENCODING_MANCHESTER)
547 		return -EINVAL;
548 
549 	if (parity != PARITY_NONE &&
550 	    parity != PARITY_CRC16_PR0 &&
551 	    parity != PARITY_CRC16_PR1 &&
552 	    parity != PARITY_CRC16_PR0_CCITT &&
553 	    parity != PARITY_CRC16_PR1_CCITT)
554 		return -EINVAL;
555 
556 	dev_to_port(dev)->encoding = encoding;
557 	dev_to_port(dev)->parity = parity;
558 	return 0;
559 }
560 
561 
562 #ifdef DEBUG_RINGS
563 static void sca_dump_rings(struct net_device *dev)
564 {
565 	port_t *port = dev_to_port(dev);
566 	card_t *card = port_to_card(port);
567 	u16 cnt;
568 #ifndef PAGE0_ALWAYS_MAPPED
569 	u8 page = sca_get_page(card);
570 
571 	openwin(card, 0);
572 #endif
573 
574 	printk(KERN_DEBUG "RX ring: CDA=%u EDA=%u DSR=%02X in=%u %sactive",
575 	       sca_inw(get_dmac_rx(port) + CDAL, card),
576 	       sca_inw(get_dmac_rx(port) + EDAL, card),
577 	       sca_in(DSR_RX(phy_node(port)), card), port->rxin,
578 	       sca_in(DSR_RX(phy_node(port)), card) & DSR_DE ? "" : "in");
579 	for (cnt = 0; cnt < port_to_card(port)->rx_ring_buffers; cnt++)
580 		pr_cont(" %02X", readb(&(desc_address(port, cnt, 0)->stat)));
581 	pr_cont("\n");
582 
583 	printk(KERN_DEBUG "TX ring: CDA=%u EDA=%u DSR=%02X in=%u "
584 	       "last=%u %sactive",
585 	       sca_inw(get_dmac_tx(port) + CDAL, card),
586 	       sca_inw(get_dmac_tx(port) + EDAL, card),
587 	       sca_in(DSR_TX(phy_node(port)), card), port->txin, port->txlast,
588 	       sca_in(DSR_TX(phy_node(port)), card) & DSR_DE ? "" : "in");
589 
590 	for (cnt = 0; cnt < port_to_card(port)->tx_ring_buffers; cnt++)
591 		pr_cont(" %02X", readb(&(desc_address(port, cnt, 1)->stat)));
592 	pr_cont("\n");
593 
594 	printk(KERN_DEBUG "MSCI: MD: %02x %02x %02x, ST: %02x %02x %02x %02x,"
595 	       " FST: %02x CST: %02x %02x\n",
596 	       sca_in(get_msci(port) + MD0, card),
597 	       sca_in(get_msci(port) + MD1, card),
598 	       sca_in(get_msci(port) + MD2, card),
599 	       sca_in(get_msci(port) + ST0, card),
600 	       sca_in(get_msci(port) + ST1, card),
601 	       sca_in(get_msci(port) + ST2, card),
602 	       sca_in(get_msci(port) + ST3, card),
603 	       sca_in(get_msci(port) + FST, card),
604 	       sca_in(get_msci(port) + CST0, card),
605 	       sca_in(get_msci(port) + CST1, card));
606 
607 	printk(KERN_DEBUG "ISR: %02x %02x %02x\n", sca_in(ISR0, card),
608 	       sca_in(ISR1, card), sca_in(ISR2, card));
609 
610 #ifndef PAGE0_ALWAYS_MAPPED
611 	openwin(card, page); /* Restore original page */
612 #endif
613 }
614 #endif /* DEBUG_RINGS */
615 
616 
617 static netdev_tx_t sca_xmit(struct sk_buff *skb, struct net_device *dev)
618 {
619 	port_t *port = dev_to_port(dev);
620 	card_t *card = port_to_card(port);
621 	pkt_desc __iomem *desc;
622 	u32 buff, len;
623 	u8 page;
624 	u32 maxlen;
625 
626 	spin_lock_irq(&port->lock);
627 
628 	desc = desc_address(port, port->txin + 1, 1);
629 	BUG_ON(readb(&desc->stat)); /* previous xmit should stop queue */
630 
631 #ifdef DEBUG_PKT
632 	printk(KERN_DEBUG "%s TX(%i):", dev->name, skb->len);
633 	debug_frame(skb);
634 #endif
635 
636 	desc = desc_address(port, port->txin, 1);
637 	buff = buffer_offset(port, port->txin, 1);
638 	len = skb->len;
639 	page = buff / winsize(card);
640 	buff = buff % winsize(card);
641 	maxlen = winsize(card) - buff;
642 
643 	openwin(card, page);
644 	if (len > maxlen) {
645 		memcpy_toio(winbase(card) + buff, skb->data, maxlen);
646 		openwin(card, page + 1);
647 		memcpy_toio(winbase(card), skb->data + maxlen, len - maxlen);
648 	} else
649 		memcpy_toio(winbase(card) + buff, skb->data, len);
650 
651 #ifndef PAGE0_ALWAYS_MAPPED
652 	openwin(card, 0);	/* select pkt_desc table page back */
653 #endif
654 	writew(len, &desc->len);
655 	writeb(ST_TX_EOM, &desc->stat);
656 
657 	port->txin = next_desc(port, port->txin, 1);
658 	sca_outw(desc_offset(port, port->txin, 1),
659 		 get_dmac_tx(port) + EDAL, card);
660 
661 	sca_out(DSR_DE, DSR_TX(phy_node(port)), card); /* Enable TX DMA */
662 
663 	desc = desc_address(port, port->txin + 1, 1);
664 	if (readb(&desc->stat)) /* allow 1 packet gap */
665 		netif_stop_queue(dev);
666 
667 	spin_unlock_irq(&port->lock);
668 
669 	dev_kfree_skb(skb);
670 	return NETDEV_TX_OK;
671 }
672 
673 
674 #ifdef NEED_DETECT_RAM
675 static u32 sca_detect_ram(card_t *card, u8 __iomem *rambase, u32 ramsize)
676 {
677 	/* Round RAM size to 32 bits, fill from end to start */
678 	u32 i = ramsize &= ~3;
679 	u32 size = winsize(card);
680 
681 	openwin(card, (i - 4) / size); /* select last window */
682 
683 	do {
684 		i -= 4;
685 		if ((i + 4) % size == 0)
686 			openwin(card, i / size);
687 		writel(i ^ 0x12345678, rambase + i % size);
688 	} while (i > 0);
689 
690 	for (i = 0; i < ramsize ; i += 4) {
691 		if (i % size == 0)
692 			openwin(card, i / size);
693 
694 		if (readl(rambase + i % size) != (i ^ 0x12345678))
695 			break;
696 	}
697 
698 	return i;
699 }
700 #endif /* NEED_DETECT_RAM */
701 
702 
703 static void sca_init(card_t *card, int wait_states)
704 {
705 	sca_out(wait_states, WCRL, card); /* Wait Control */
706 	sca_out(wait_states, WCRM, card);
707 	sca_out(wait_states, WCRH, card);
708 
709 	sca_out(0, DMER, card);	/* DMA Master disable */
710 	sca_out(0x03, PCR, card); /* DMA priority */
711 	sca_out(0, DSR_RX(0), card); /* DMA disable - to halt state */
712 	sca_out(0, DSR_TX(0), card);
713 	sca_out(0, DSR_RX(1), card);
714 	sca_out(0, DSR_TX(1), card);
715 	sca_out(DMER_DME, DMER, card); /* DMA Master enable */
716 }
717