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1/*
2 * Hitachi (now Renesas) SCA-II HD64572 driver for Linux
3 *
4 * Copyright (C) 1998-2008 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: HD64572 SCA-II User's Manual
11 *
12 * We use the following SCA memory map:
13 *
14 * Packet buffer descriptor rings - starting from card->rambase:
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 card->rambase + 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/init.h>
33#include <linux/interrupt.h>
34#include <linux/ioport.h>
35#include <linux/jiffies.h>
36#include <linux/kernel.h>
37#include <linux/module.h>
38#include <linux/netdevice.h>
39#include <linux/skbuff.h>
40#include <linux/string.h>
41#include <linux/types.h>
42#include <asm/io.h>
43#include <asm/system.h>
44#include <asm/uaccess.h>
45#include "hd64572.h"
46
47#define NAPI_WEIGHT		16
48
49#define get_msci(port)	  (port->chan ?   MSCI1_OFFSET :   MSCI0_OFFSET)
50#define get_dmac_rx(port) (port->chan ? DMAC1RX_OFFSET : DMAC0RX_OFFSET)
51#define get_dmac_tx(port) (port->chan ? DMAC1TX_OFFSET : DMAC0TX_OFFSET)
52
53#define sca_in(reg, card)	     readb(card->scabase + (reg))
54#define sca_out(value, reg, card)    writeb(value, card->scabase + (reg))
55#define sca_inw(reg, card)	     readw(card->scabase + (reg))
56#define sca_outw(value, reg, card)   writew(value, card->scabase + (reg))
57#define sca_inl(reg, card)	     readl(card->scabase + (reg))
58#define sca_outl(value, reg, card)   writel(value, card->scabase + (reg))
59
60static int sca_poll(struct napi_struct *napi, int budget);
61
62static inline port_t* dev_to_port(struct net_device *dev)
63{
64	return dev_to_hdlc(dev)->priv;
65}
66
67static inline void enable_intr(port_t *port)
68{
69	/* enable DMIB and MSCI RXINTA interrupts */
70	sca_outl(sca_inl(IER0, port->card) |
71		 (port->chan ? 0x08002200 : 0x00080022), IER0, port->card);
72}
73
74static inline void disable_intr(port_t *port)
75{
76	sca_outl(sca_inl(IER0, port->card) &
77		 (port->chan ? 0x00FF00FF : 0xFF00FF00), IER0, port->card);
78}
79
80static inline u16 desc_abs_number(port_t *port, u16 desc, int transmit)
81{
82	u16 rx_buffs = port->card->rx_ring_buffers;
83	u16 tx_buffs = port->card->tx_ring_buffers;
84
85	desc %= (transmit ? tx_buffs : rx_buffs); // called with "X + 1" etc.
86	return port->chan * (rx_buffs + tx_buffs) + transmit * rx_buffs + desc;
87}
88
89
90static inline u16 desc_offset(port_t *port, u16 desc, int transmit)
91{
92	/* Descriptor offset always fits in 16 bits */
93	return desc_abs_number(port, desc, transmit) * sizeof(pkt_desc);
94}
95
96
97static inline pkt_desc __iomem *desc_address(port_t *port, u16 desc,
98					     int transmit)
99{
100	return (pkt_desc __iomem *)(port->card->rambase +
101				    desc_offset(port, desc, transmit));
102}
103
104
105static inline u32 buffer_offset(port_t *port, u16 desc, int transmit)
106{
107	return port->card->buff_offset +
108		desc_abs_number(port, desc, transmit) * (u32)HDLC_MAX_MRU;
109}
110
111
112static inline void sca_set_carrier(port_t *port)
113{
114	if (!(sca_in(get_msci(port) + ST3, port->card) & ST3_DCD)) {
115#ifdef DEBUG_LINK
116		printk(KERN_DEBUG "%s: sca_set_carrier on\n",
117		       port->netdev.name);
118#endif
119		netif_carrier_on(port->netdev);
120	} else {
121#ifdef DEBUG_LINK
122		printk(KERN_DEBUG "%s: sca_set_carrier off\n",
123		       port->netdev.name);
124#endif
125		netif_carrier_off(port->netdev);
126	}
127}
128
129
130static void sca_init_port(port_t *port)
131{
132	card_t *card = port->card;
133	u16 dmac_rx = get_dmac_rx(port), dmac_tx = get_dmac_tx(port);
134	int transmit, i;
135
136	port->rxin = 0;
137	port->txin = 0;
138	port->txlast = 0;
139
140	for (transmit = 0; transmit < 2; transmit++) {
141		u16 buffs = transmit ? card->tx_ring_buffers
142			: card->rx_ring_buffers;
143
144		for (i = 0; i < buffs; i++) {
145			pkt_desc __iomem *desc = desc_address(port, i, transmit);
146			u16 chain_off = desc_offset(port, i + 1, transmit);
147			u32 buff_off = buffer_offset(port, i, transmit);
148
149			writel(chain_off, &desc->cp);
150			writel(buff_off, &desc->bp);
151			writew(0, &desc->len);
152			writeb(0, &desc->stat);
153		}
154	}
155
156	/* DMA disable - to halt state */
157	sca_out(0, DSR_RX(port->chan), card);
158	sca_out(0, DSR_TX(port->chan), card);
159
160	/* software ABORT - to initial state */
161	sca_out(DCR_ABORT, DCR_RX(port->chan), card);
162	sca_out(DCR_ABORT, DCR_TX(port->chan), card);
163
164	/* current desc addr */
165	sca_outl(desc_offset(port, 0, 0), dmac_rx + CDAL, card);
166	sca_outl(desc_offset(port, card->tx_ring_buffers - 1, 0),
167		 dmac_rx + EDAL, card);
168	sca_outl(desc_offset(port, 0, 1), dmac_tx + CDAL, card);
169	sca_outl(desc_offset(port, 0, 1), dmac_tx + EDAL, card);
170
171	/* clear frame end interrupt counter */
172	sca_out(DCR_CLEAR_EOF, DCR_RX(port->chan), card);
173	sca_out(DCR_CLEAR_EOF, DCR_TX(port->chan), card);
174
175	/* Receive */
176	sca_outw(HDLC_MAX_MRU, dmac_rx + BFLL, card); /* set buffer length */
177	sca_out(0x14, DMR_RX(port->chan), card); /* Chain mode, Multi-frame */
178	sca_out(DIR_EOME, DIR_RX(port->chan), card); /* enable interrupts */
179	sca_out(DSR_DE, DSR_RX(port->chan), card); /* DMA enable */
180
181	/* Transmit */
182	sca_out(0x14, DMR_TX(port->chan), card); /* Chain mode, Multi-frame */
183	sca_out(DIR_EOME, DIR_TX(port->chan), card); /* enable interrupts */
184
185	sca_set_carrier(port);
186	netif_napi_add(port->netdev, &port->napi, sca_poll, NAPI_WEIGHT);
187}
188
189
190/* MSCI interrupt service */
191static inline void sca_msci_intr(port_t *port)
192{
193	u16 msci = get_msci(port);
194	card_t* card = port->card;
195
196	if (sca_in(msci + ST1, card) & ST1_CDCD) {
197		/* Reset MSCI CDCD status bit */
198		sca_out(ST1_CDCD, msci + ST1, card);
199		sca_set_carrier(port);
200	}
201}
202
203
204static inline void sca_rx(card_t *card, port_t *port, pkt_desc __iomem *desc,
205			  u16 rxin)
206{
207	struct net_device *dev = port->netdev;
208	struct sk_buff *skb;
209	u16 len;
210	u32 buff;
211
212	len = readw(&desc->len);
213	skb = dev_alloc_skb(len);
214	if (!skb) {
215		dev->stats.rx_dropped++;
216		return;
217	}
218
219	buff = buffer_offset(port, rxin, 0);
220	memcpy_fromio(skb->data, card->rambase + buff, len);
221
222	skb_put(skb, len);
223#ifdef DEBUG_PKT
224	printk(KERN_DEBUG "%s RX(%i):", dev->name, skb->len);
225	debug_frame(skb);
226#endif
227	dev->stats.rx_packets++;
228	dev->stats.rx_bytes += skb->len;
229	skb->protocol = hdlc_type_trans(skb, dev);
230	netif_receive_skb(skb);
231}
232
233
234/* Receive DMA service */
235static inline int sca_rx_done(port_t *port, int budget)
236{
237	struct net_device *dev = port->netdev;
238	u16 dmac = get_dmac_rx(port);
239	card_t *card = port->card;
240	u8 stat = sca_in(DSR_RX(port->chan), card); /* read DMA Status */
241	int received = 0;
242
243	/* Reset DSR status bits */
244	sca_out((stat & (DSR_EOT | DSR_EOM | DSR_BOF | DSR_COF)) | DSR_DWE,
245		DSR_RX(port->chan), card);
246
247	if (stat & DSR_BOF)
248		/* Dropped one or more frames */
249		dev->stats.rx_over_errors++;
250
251	while (received < budget) {
252		u32 desc_off = desc_offset(port, port->rxin, 0);
253		pkt_desc __iomem *desc;
254		u32 cda = sca_inl(dmac + CDAL, card);
255
256		if ((cda >= desc_off) && (cda < desc_off + sizeof(pkt_desc)))
257			break;	/* No frame received */
258
259		desc = desc_address(port, port->rxin, 0);
260		stat = readb(&desc->stat);
261		if (!(stat & ST_RX_EOM))
262			port->rxpart = 1; /* partial frame received */
263		else if ((stat & ST_ERROR_MASK) || port->rxpart) {
264			dev->stats.rx_errors++;
265			if (stat & ST_RX_OVERRUN)
266				dev->stats.rx_fifo_errors++;
267			else if ((stat & (ST_RX_SHORT | ST_RX_ABORT |
268					  ST_RX_RESBIT)) || port->rxpart)
269				dev->stats.rx_frame_errors++;
270			else if (stat & ST_RX_CRC)
271				dev->stats.rx_crc_errors++;
272			if (stat & ST_RX_EOM)
273				port->rxpart = 0; /* received last fragment */
274		} else {
275			sca_rx(card, port, desc, port->rxin);
276			received++;
277		}
278
279		/* Set new error descriptor address */
280		sca_outl(desc_off, dmac + EDAL, card);
281		port->rxin = (port->rxin + 1) % card->rx_ring_buffers;
282	}
283
284	/* make sure RX DMA is enabled */
285	sca_out(DSR_DE, DSR_RX(port->chan), card);
286	return received;
287}
288
289
290/* Transmit DMA service */
291static inline void sca_tx_done(port_t *port)
292{
293	struct net_device *dev = port->netdev;
294	card_t* card = port->card;
295	u8 stat;
296
297	spin_lock(&port->lock);
298
299	stat = sca_in(DSR_TX(port->chan), card); /* read DMA Status */
300
301	/* Reset DSR status bits */
302	sca_out((stat & (DSR_EOT | DSR_EOM | DSR_BOF | DSR_COF)) | DSR_DWE,
303		DSR_TX(port->chan), card);
304
305	while (1) {
306		pkt_desc __iomem *desc = desc_address(port, port->txlast, 1);
307		u8 stat = readb(&desc->stat);
308
309		if (!(stat & ST_TX_OWNRSHP))
310			break; /* not yet transmitted */
311		if (stat & ST_TX_UNDRRUN) {
312			dev->stats.tx_errors++;
313			dev->stats.tx_fifo_errors++;
314		} else {
315			dev->stats.tx_packets++;
316			dev->stats.tx_bytes += readw(&desc->len);
317		}
318		writeb(0, &desc->stat);	/* Free descriptor */
319		port->txlast = (port->txlast + 1) % card->tx_ring_buffers;
320	}
321
322	netif_wake_queue(dev);
323	spin_unlock(&port->lock);
324}
325
326
327static int sca_poll(struct napi_struct *napi, int budget)
328{
329	port_t *port = container_of(napi, port_t, napi);
330	u32 isr0 = sca_inl(ISR0, port->card);
331	int received = 0;
332
333	if (isr0 & (port->chan ? 0x08000000 : 0x00080000))
334		sca_msci_intr(port);
335
336	if (isr0 & (port->chan ? 0x00002000 : 0x00000020))
337		sca_tx_done(port);
338
339	if (isr0 & (port->chan ? 0x00000200 : 0x00000002))
340		received = sca_rx_done(port, budget);
341
342	if (received < budget) {
343		napi_complete(napi);
344		enable_intr(port);
345	}
346
347	return received;
348}
349
350static irqreturn_t sca_intr(int irq, void *dev_id)
351{
352	card_t *card = dev_id;
353	u32 isr0 = sca_inl(ISR0, card);
354	int i, handled = 0;
355
356	for (i = 0; i < 2; i++) {
357		port_t *port = get_port(card, i);
358		if (port && (isr0 & (i ? 0x08002200 : 0x00080022))) {
359			handled = 1;
360			disable_intr(port);
361			napi_schedule(&port->napi);
362		}
363	}
364
365	return IRQ_RETVAL(handled);
366}
367
368
369static void sca_set_port(port_t *port)
370{
371	card_t* card = port->card;
372	u16 msci = get_msci(port);
373	u8 md2 = sca_in(msci + MD2, card);
374	unsigned int tmc, br = 10, brv = 1024;
375
376
377	if (port->settings.clock_rate > 0) {
378		/* Try lower br for better accuracy*/
379		do {
380			br--;
381			brv >>= 1; /* brv = 2^9 = 512 max in specs */
382
383			/* Baud Rate = CLOCK_BASE / TMC / 2^BR */
384			tmc = CLOCK_BASE / brv / port->settings.clock_rate;
385		}while (br > 1 && tmc <= 128);
386
387		if (tmc < 1) {
388			tmc = 1;
389			br = 0;	/* For baud=CLOCK_BASE we use tmc=1 br=0 */
390			brv = 1;
391		} else if (tmc > 255)
392			tmc = 256; /* tmc=0 means 256 - low baud rates */
393
394		port->settings.clock_rate = CLOCK_BASE / brv / tmc;
395	} else {
396		br = 9; /* Minimum clock rate */
397		tmc = 256;	/* 8bit = 0 */
398		port->settings.clock_rate = CLOCK_BASE / (256 * 512);
399	}
400
401	port->rxs = (port->rxs & ~CLK_BRG_MASK) | br;
402	port->txs = (port->txs & ~CLK_BRG_MASK) | br;
403	port->tmc = tmc;
404
405	/* baud divisor - time constant*/
406	sca_out(port->tmc, msci + TMCR, card);
407	sca_out(port->tmc, msci + TMCT, card);
408
409	/* Set BRG bits */
410	sca_out(port->rxs, msci + RXS, card);
411	sca_out(port->txs, msci + TXS, card);
412
413	if (port->settings.loopback)
414		md2 |= MD2_LOOPBACK;
415	else
416		md2 &= ~MD2_LOOPBACK;
417
418	sca_out(md2, msci + MD2, card);
419
420}
421
422
423static void sca_open(struct net_device *dev)
424{
425	port_t *port = dev_to_port(dev);
426	card_t* card = port->card;
427	u16 msci = get_msci(port);
428	u8 md0, md2;
429
430	switch(port->encoding) {
431	case ENCODING_NRZ:	md2 = MD2_NRZ;		break;
432	case ENCODING_NRZI:	md2 = MD2_NRZI;		break;
433	case ENCODING_FM_MARK:	md2 = MD2_FM_MARK;	break;
434	case ENCODING_FM_SPACE:	md2 = MD2_FM_SPACE;	break;
435	default:		md2 = MD2_MANCHESTER;
436	}
437
438	if (port->settings.loopback)
439		md2 |= MD2_LOOPBACK;
440
441	switch(port->parity) {
442	case PARITY_CRC16_PR0:	     md0 = MD0_HDLC | MD0_CRC_16_0;  break;
443	case PARITY_CRC16_PR1:	     md0 = MD0_HDLC | MD0_CRC_16;    break;
444	case PARITY_CRC32_PR1_CCITT: md0 = MD0_HDLC | MD0_CRC_ITU32; break;
445	case PARITY_CRC16_PR1_CCITT: md0 = MD0_HDLC | MD0_CRC_ITU;   break;
446	default:		     md0 = MD0_HDLC | MD0_CRC_NONE;
447	}
448
449	sca_out(CMD_RESET, msci + CMD, card);
450	sca_out(md0, msci + MD0, card);
451	sca_out(0x00, msci + MD1, card); /* no address field check */
452	sca_out(md2, msci + MD2, card);
453	sca_out(0x7E, msci + IDL, card); /* flag character 0x7E */
454	/* Skip the rest of underrun frame */
455	sca_out(CTL_IDLE | CTL_URCT | CTL_URSKP, msci + CTL, card);
456	sca_out(0x0F, msci + RNR, card); /* +1=RX DMA activation condition */
457	sca_out(0x3C, msci + TFS, card); /* +1 = TX start */
458	sca_out(0x38, msci + TCR, card); /* =Critical TX DMA activ condition */
459	sca_out(0x38, msci + TNR0, card); /* =TX DMA activation condition */
460	sca_out(0x3F, msci + TNR1, card); /* +1=TX DMA deactivation condition*/
461
462/* We're using the following interrupts:
463   - RXINTA (DCD changes only)
464   - DMIB (EOM - single frame transfer complete)
465*/
466	sca_outl(IE0_RXINTA | IE0_CDCD, msci + IE0, card);
467
468	sca_out(port->tmc, msci + TMCR, card);
469	sca_out(port->tmc, msci + TMCT, card);
470	sca_out(port->rxs, msci + RXS, card);
471	sca_out(port->txs, msci + TXS, card);
472	sca_out(CMD_TX_ENABLE, msci + CMD, card);
473	sca_out(CMD_RX_ENABLE, msci + CMD, card);
474
475	sca_set_carrier(port);
476	enable_intr(port);
477	napi_enable(&port->napi);
478	netif_start_queue(dev);
479}
480
481
482static void sca_close(struct net_device *dev)
483{
484	port_t *port = dev_to_port(dev);
485
486	/* reset channel */
487	sca_out(CMD_RESET, get_msci(port) + CMD, port->card);
488	disable_intr(port);
489	napi_disable(&port->napi);
490	netif_stop_queue(dev);
491}
492
493
494static int sca_attach(struct net_device *dev, unsigned short encoding,
495		      unsigned short parity)
496{
497	if (encoding != ENCODING_NRZ &&
498	    encoding != ENCODING_NRZI &&
499	    encoding != ENCODING_FM_MARK &&
500	    encoding != ENCODING_FM_SPACE &&
501	    encoding != ENCODING_MANCHESTER)
502		return -EINVAL;
503
504	if (parity != PARITY_NONE &&
505	    parity != PARITY_CRC16_PR0 &&
506	    parity != PARITY_CRC16_PR1 &&
507	    parity != PARITY_CRC32_PR1_CCITT &&
508	    parity != PARITY_CRC16_PR1_CCITT)
509		return -EINVAL;
510
511	dev_to_port(dev)->encoding = encoding;
512	dev_to_port(dev)->parity = parity;
513	return 0;
514}
515
516
517#ifdef DEBUG_RINGS
518static void sca_dump_rings(struct net_device *dev)
519{
520	port_t *port = dev_to_port(dev);
521	card_t *card = port->card;
522	u16 cnt;
523
524	printk(KERN_DEBUG "RX ring: CDA=%u EDA=%u DSR=%02X in=%u %sactive",
525	       sca_inl(get_dmac_rx(port) + CDAL, card),
526	       sca_inl(get_dmac_rx(port) + EDAL, card),
527	       sca_in(DSR_RX(port->chan), card), port->rxin,
528	       sca_in(DSR_RX(port->chan), card) & DSR_DE ? "" : "in");
529	for (cnt = 0; cnt < port->card->rx_ring_buffers; cnt++)
530		printk(" %02X", readb(&(desc_address(port, cnt, 0)->stat)));
531	printk(KERN_CONT "\n");
532
533	printk(KERN_DEBUG "TX ring: CDA=%u EDA=%u DSR=%02X in=%u "
534	       "last=%u %sactive",
535	       sca_inl(get_dmac_tx(port) + CDAL, card),
536	       sca_inl(get_dmac_tx(port) + EDAL, card),
537	       sca_in(DSR_TX(port->chan), card), port->txin, port->txlast,
538	       sca_in(DSR_TX(port->chan), card) & DSR_DE ? "" : "in");
539
540	for (cnt = 0; cnt < port->card->tx_ring_buffers; cnt++)
541		printk(" %02X", readb(&(desc_address(port, cnt, 1)->stat)));
542	printk("\n");
543
544	printk(KERN_DEBUG "MSCI: MD: %02x %02x %02x,"
545	       " ST: %02x %02x %02x %02x %02x, FST: %02x CST: %02x %02x\n",
546	       sca_in(get_msci(port) + MD0, card),
547	       sca_in(get_msci(port) + MD1, card),
548	       sca_in(get_msci(port) + MD2, card),
549	       sca_in(get_msci(port) + ST0, card),
550	       sca_in(get_msci(port) + ST1, card),
551	       sca_in(get_msci(port) + ST2, card),
552	       sca_in(get_msci(port) + ST3, card),
553	       sca_in(get_msci(port) + ST4, card),
554	       sca_in(get_msci(port) + FST, card),
555	       sca_in(get_msci(port) + CST0, card),
556	       sca_in(get_msci(port) + CST1, card));
557
558	printk(KERN_DEBUG "ILAR: %02x ISR: %08x %08x\n", sca_in(ILAR, card),
559	       sca_inl(ISR0, card), sca_inl(ISR1, card));
560}
561#endif /* DEBUG_RINGS */
562
563
564static netdev_tx_t sca_xmit(struct sk_buff *skb, struct net_device *dev)
565{
566	port_t *port = dev_to_port(dev);
567	card_t *card = port->card;
568	pkt_desc __iomem *desc;
569	u32 buff, len;
570
571	spin_lock_irq(&port->lock);
572
573	desc = desc_address(port, port->txin + 1, 1);
574	BUG_ON(readb(&desc->stat)); /* previous xmit should stop queue */
575
576#ifdef DEBUG_PKT
577	printk(KERN_DEBUG "%s TX(%i):", dev->name, skb->len);
578	debug_frame(skb);
579#endif
580
581	desc = desc_address(port, port->txin, 1);
582	buff = buffer_offset(port, port->txin, 1);
583	len = skb->len;
584	memcpy_toio(card->rambase + buff, skb->data, len);
585
586	writew(len, &desc->len);
587	writeb(ST_TX_EOM, &desc->stat);
588
589	port->txin = (port->txin + 1) % card->tx_ring_buffers;
590	sca_outl(desc_offset(port, port->txin, 1),
591		 get_dmac_tx(port) + EDAL, card);
592
593	sca_out(DSR_DE, DSR_TX(port->chan), card); /* Enable TX DMA */
594
595	desc = desc_address(port, port->txin + 1, 1);
596	if (readb(&desc->stat)) /* allow 1 packet gap */
597		netif_stop_queue(dev);
598
599	spin_unlock_irq(&port->lock);
600
601	dev_kfree_skb(skb);
602	return NETDEV_TX_OK;
603}
604
605
606static u32 __devinit sca_detect_ram(card_t *card, u8 __iomem *rambase,
607				    u32 ramsize)
608{
609	/* Round RAM size to 32 bits, fill from end to start */
610	u32 i = ramsize &= ~3;
611
612	do {
613		i -= 4;
614		writel(i ^ 0x12345678, rambase + i);
615	} while (i > 0);
616
617	for (i = 0; i < ramsize ; i += 4) {
618		if (readl(rambase + i) != (i ^ 0x12345678))
619			break;
620	}
621
622	return i;
623}
624
625
626static void __devinit sca_init(card_t *card, int wait_states)
627{
628	sca_out(wait_states, WCRL, card); /* Wait Control */
629	sca_out(wait_states, WCRM, card);
630	sca_out(wait_states, WCRH, card);
631
632	sca_out(0, DMER, card);	/* DMA Master disable */
633	sca_out(0x03, PCR, card); /* DMA priority */
634	sca_out(0, DSR_RX(0), card); /* DMA disable - to halt state */
635	sca_out(0, DSR_TX(0), card);
636	sca_out(0, DSR_RX(1), card);
637	sca_out(0, DSR_TX(1), card);
638	sca_out(DMER_DME, DMER, card); /* DMA Master enable */
639}
640