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
50static inline struct net_device *port_to_dev(port_t *port)
51{
52	return port->dev;
53}
54
55static 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
84static inline port_t *dev_to_port(struct net_device *dev)
85{
86	return dev_to_hdlc(dev)->priv;
87}
88
89static 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
95static 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
105static 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
111static 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
123static 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
129static 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
146static 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 */
217static 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
237static 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 */
284static 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 */
336static 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
371static 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
401static 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
452static 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
533static 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
550static 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
573static 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
626static 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
684static 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
711static 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