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Add linux-next specific files for 20110831
[linux-2.6/next.git] / drivers / net / wan / hd64572.c
blobefc0db101183f2eb26673190c4eaaebe5e17ec9c
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
60 static int sca_poll(struct napi_struct *napi, int budget);
61
62 static inline port_t* dev_to_port(struct net_device *dev)
63 {
64 return dev_to_hdlc(dev)->priv;
65 }
66
67 static 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
74 static 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
80 static 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
90 static 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
97 static 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
105 static 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
112 static 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
130 static 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 */
191 static 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
204 static 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 */
235 static 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 */
291 static 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 unsigned count = 0;
297
298 spin_lock(&port->lock);
299
300 stat = sca_in(DSR_TX(port->chan), card); /* read DMA Status */
301
302 /* Reset DSR status bits */
303 sca_out((stat & (DSR_EOT | DSR_EOM | DSR_BOF | DSR_COF)) | DSR_DWE,
304 DSR_TX(port->chan), card);
305
306 while (1) {
307 pkt_desc __iomem *desc = desc_address(port, port->txlast, 1);
308 u8 stat = readb(&desc->stat);
309
310 if (!(stat & ST_TX_OWNRSHP))
311 break; /* not yet transmitted */
312 if (stat & ST_TX_UNDRRUN) {
313 dev->stats.tx_errors++;
314 dev->stats.tx_fifo_errors++;
315 } else {
316 dev->stats.tx_packets++;
317 dev->stats.tx_bytes += readw(&desc->len);
318 }
319 writeb(0, &desc->stat); /* Free descriptor */
320 count++;
321 port->txlast = (port->txlast + 1) % card->tx_ring_buffers;
322 }
323
324 if (count)
325 netif_wake_queue(dev);
326 spin_unlock(&port->lock);
327 }
328
329
330 static int sca_poll(struct napi_struct *napi, int budget)
331 {
332 port_t *port = container_of(napi, port_t, napi);
333 u32 isr0 = sca_inl(ISR0, port->card);
334 int received = 0;
335
336 if (isr0 & (port->chan ? 0x08000000 : 0x00080000))
337 sca_msci_intr(port);
338
339 if (isr0 & (port->chan ? 0x00002000 : 0x00000020))
340 sca_tx_done(port);
341
342 if (isr0 & (port->chan ? 0x00000200 : 0x00000002))
343 received = sca_rx_done(port, budget);
344
345 if (received < budget) {
346 napi_complete(napi);
347 enable_intr(port);
348 }
349
350 return received;
351 }
352
353 static irqreturn_t sca_intr(int irq, void *dev_id)
354 {
355 card_t *card = dev_id;
356 u32 isr0 = sca_inl(ISR0, card);
357 int i, handled = 0;
358
359 for (i = 0; i < 2; i++) {
360 port_t *port = get_port(card, i);
361 if (port && (isr0 & (i ? 0x08002200 : 0x00080022))) {
362 handled = 1;
363 disable_intr(port);
364 napi_schedule(&port->napi);
365 }
366 }
367
368 return IRQ_RETVAL(handled);
369 }
370
371
372 static void sca_set_port(port_t *port)
373 {
374 card_t* card = port->card;
375 u16 msci = get_msci(port);
376 u8 md2 = sca_in(msci + MD2, card);
377 unsigned int tmc, br = 10, brv = 1024;
378
379
380 if (port->settings.clock_rate > 0) {
381 /* Try lower br for better accuracy*/
382 do {
383 br--;
384 brv >>= 1; /* brv = 2^9 = 512 max in specs */
385
386 /* Baud Rate = CLOCK_BASE / TMC / 2^BR */
387 tmc = CLOCK_BASE / brv / port->settings.clock_rate;
388 }while (br > 1 && tmc <= 128);
389
390 if (tmc < 1) {
391 tmc = 1;
392 br = 0; /* For baud=CLOCK_BASE we use tmc=1 br=0 */
393 brv = 1;
394 } else if (tmc > 255)
395 tmc = 256; /* tmc=0 means 256 - low baud rates */
396
397 port->settings.clock_rate = CLOCK_BASE / brv / tmc;
398 } else {
399 br = 9; /* Minimum clock rate */
400 tmc = 256; /* 8bit = 0 */
401 port->settings.clock_rate = CLOCK_BASE / (256 * 512);
402 }
403
404 port->rxs = (port->rxs & ~CLK_BRG_MASK) | br;
405 port->txs = (port->txs & ~CLK_BRG_MASK) | br;
406 port->tmc = tmc;
407
408 /* baud divisor - time constant*/
409 sca_out(port->tmc, msci + TMCR, card);
410 sca_out(port->tmc, msci + TMCT, card);
411
412 /* Set BRG bits */
413 sca_out(port->rxs, msci + RXS, card);
414 sca_out(port->txs, msci + TXS, card);
415
416 if (port->settings.loopback)
417 md2 |= MD2_LOOPBACK;
418 else
419 md2 &= ~MD2_LOOPBACK;
420
421 sca_out(md2, msci + MD2, card);
422
423 }
424
425
426 static void sca_open(struct net_device *dev)
427 {
428 port_t *port = dev_to_port(dev);
429 card_t* card = port->card;
430 u16 msci = get_msci(port);
431 u8 md0, md2;
432
433 switch(port->encoding) {
434 case ENCODING_NRZ: md2 = MD2_NRZ; break;
435 case ENCODING_NRZI: md2 = MD2_NRZI; break;
436 case ENCODING_FM_MARK: md2 = MD2_FM_MARK; break;
437 case ENCODING_FM_SPACE: md2 = MD2_FM_SPACE; break;
438 default: md2 = MD2_MANCHESTER;
439 }
440
441 if (port->settings.loopback)
442 md2 |= MD2_LOOPBACK;
443
444 switch(port->parity) {
445 case PARITY_CRC16_PR0: md0 = MD0_HDLC | MD0_CRC_16_0; break;
446 case PARITY_CRC16_PR1: md0 = MD0_HDLC | MD0_CRC_16; break;
447 case PARITY_CRC32_PR1_CCITT: md0 = MD0_HDLC | MD0_CRC_ITU32; break;
448 case PARITY_CRC16_PR1_CCITT: md0 = MD0_HDLC | MD0_CRC_ITU; break;
449 default: md0 = MD0_HDLC | MD0_CRC_NONE;
450 }
451
452 sca_out(CMD_RESET, msci + CMD, card);
453 sca_out(md0, msci + MD0, card);
454 sca_out(0x00, msci + MD1, card); /* no address field check */
455 sca_out(md2, msci + MD2, card);
456 sca_out(0x7E, msci + IDL, card); /* flag character 0x7E */
457 /* Skip the rest of underrun frame */
458 sca_out(CTL_IDLE | CTL_URCT | CTL_URSKP, msci + CTL, card);
459 sca_out(0x0F, msci + RNR, card); /* +1=RX DMA activation condition */
460 sca_out(0x3C, msci + TFS, card); /* +1 = TX start */
461 sca_out(0x38, msci + TCR, card); /* =Critical TX DMA activ condition */
462 sca_out(0x38, msci + TNR0, card); /* =TX DMA activation condition */
463 sca_out(0x3F, msci + TNR1, card); /* +1=TX DMA deactivation condition*/
464
465 /* We're using the following interrupts:
466 - RXINTA (DCD changes only)
467 - DMIB (EOM - single frame transfer complete)
468 */
469 sca_outl(IE0_RXINTA | IE0_CDCD, msci + IE0, card);
470
471 sca_out(port->tmc, msci + TMCR, card);
472 sca_out(port->tmc, msci + TMCT, card);
473 sca_out(port->rxs, msci + RXS, card);
474 sca_out(port->txs, msci + TXS, card);
475 sca_out(CMD_TX_ENABLE, msci + CMD, card);
476 sca_out(CMD_RX_ENABLE, msci + CMD, card);
477
478 sca_set_carrier(port);
479 enable_intr(port);
480 napi_enable(&port->napi);
481 netif_start_queue(dev);
482 }
483
484
485 static void sca_close(struct net_device *dev)
486 {
487 port_t *port = dev_to_port(dev);
488
489 /* reset channel */
490 sca_out(CMD_RESET, get_msci(port) + CMD, port->card);
491 disable_intr(port);
492 napi_disable(&port->napi);
493 netif_stop_queue(dev);
494 }
495
496
497 static int sca_attach(struct net_device *dev, unsigned short encoding,
498 unsigned short parity)
499 {
500 if (encoding != ENCODING_NRZ &&
501 encoding != ENCODING_NRZI &&
502 encoding != ENCODING_FM_MARK &&
503 encoding != ENCODING_FM_SPACE &&
504 encoding != ENCODING_MANCHESTER)
505 return -EINVAL;
506
507 if (parity != PARITY_NONE &&
508 parity != PARITY_CRC16_PR0 &&
509 parity != PARITY_CRC16_PR1 &&
510 parity != PARITY_CRC32_PR1_CCITT &&
511 parity != PARITY_CRC16_PR1_CCITT)
512 return -EINVAL;
513
514 dev_to_port(dev)->encoding = encoding;
515 dev_to_port(dev)->parity = parity;
516 return 0;
517 }
518
519
520 #ifdef DEBUG_RINGS
521 static void sca_dump_rings(struct net_device *dev)
522 {
523 port_t *port = dev_to_port(dev);
524 card_t *card = port->card;
525 u16 cnt;
526
527 printk(KERN_DEBUG "RX ring: CDA=%u EDA=%u DSR=%02X in=%u %sactive",
528 sca_inl(get_dmac_rx(port) + CDAL, card),
529 sca_inl(get_dmac_rx(port) + EDAL, card),
530 sca_in(DSR_RX(port->chan), card), port->rxin,
531 sca_in(DSR_RX(port->chan), card) & DSR_DE ? "" : "in");
532 for (cnt = 0; cnt < port->card->rx_ring_buffers; cnt++)
533 pr_cont(" %02X", readb(&(desc_address(port, cnt, 0)->stat)));
534 pr_cont("\n");
535
536 printk(KERN_DEBUG "TX ring: CDA=%u EDA=%u DSR=%02X in=%u "
537 "last=%u %sactive",
538 sca_inl(get_dmac_tx(port) + CDAL, card),
539 sca_inl(get_dmac_tx(port) + EDAL, card),
540 sca_in(DSR_TX(port->chan), card), port->txin, port->txlast,
541 sca_in(DSR_TX(port->chan), card) & DSR_DE ? "" : "in");
542
543 for (cnt = 0; cnt < port->card->tx_ring_buffers; cnt++)
544 pr_cont(" %02X", readb(&(desc_address(port, cnt, 1)->stat)));
545 pr_cont("\n");
546
547 printk(KERN_DEBUG "MSCI: MD: %02x %02x %02x,"
548 " ST: %02x %02x %02x %02x %02x, FST: %02x CST: %02x %02x\n",
549 sca_in(get_msci(port) + MD0, card),
550 sca_in(get_msci(port) + MD1, card),
551 sca_in(get_msci(port) + MD2, card),
552 sca_in(get_msci(port) + ST0, card),
553 sca_in(get_msci(port) + ST1, card),
554 sca_in(get_msci(port) + ST2, card),
555 sca_in(get_msci(port) + ST3, card),
556 sca_in(get_msci(port) + ST4, card),
557 sca_in(get_msci(port) + FST, card),
558 sca_in(get_msci(port) + CST0, card),
559 sca_in(get_msci(port) + CST1, card));
560
561 printk(KERN_DEBUG "ILAR: %02x ISR: %08x %08x\n", sca_in(ILAR, card),
562 sca_inl(ISR0, card), sca_inl(ISR1, card));
563 }
564 #endif /* DEBUG_RINGS */
565
566
567 static netdev_tx_t sca_xmit(struct sk_buff *skb, struct net_device *dev)
568 {
569 port_t *port = dev_to_port(dev);
570 card_t *card = port->card;
571 pkt_desc __iomem *desc;
572 u32 buff, len;
573
574 spin_lock_irq(&port->lock);
575
576 desc = desc_address(port, port->txin + 1, 1);
577 BUG_ON(readb(&desc->stat)); /* previous xmit should stop queue */
578
579 #ifdef DEBUG_PKT
580 printk(KERN_DEBUG "%s TX(%i):", dev->name, skb->len);
581 debug_frame(skb);
582 #endif
583
584 desc = desc_address(port, port->txin, 1);
585 buff = buffer_offset(port, port->txin, 1);
586 len = skb->len;
587 memcpy_toio(card->rambase + buff, skb->data, len);
588
589 writew(len, &desc->len);
590 writeb(ST_TX_EOM, &desc->stat);
591
592 port->txin = (port->txin + 1) % card->tx_ring_buffers;
593 sca_outl(desc_offset(port, port->txin, 1),
594 get_dmac_tx(port) + EDAL, card);
595
596 sca_out(DSR_DE, DSR_TX(port->chan), card); /* Enable TX DMA */
597
598 desc = desc_address(port, port->txin + 1, 1);
599 if (readb(&desc->stat)) /* allow 1 packet gap */
600 netif_stop_queue(dev);
601
602 spin_unlock_irq(&port->lock);
603
604 dev_kfree_skb(skb);
605 return NETDEV_TX_OK;
606 }
607
608
609 static u32 __devinit sca_detect_ram(card_t *card, u8 __iomem *rambase,
610 u32 ramsize)
611 {
612 /* Round RAM size to 32 bits, fill from end to start */
613 u32 i = ramsize &= ~3;
614
615 do {
616 i -= 4;
617 writel(i ^ 0x12345678, rambase + i);
618 } while (i > 0);
619
620 for (i = 0; i < ramsize ; i += 4) {
621 if (readl(rambase + i) != (i ^ 0x12345678))
622 break;
623 }
624
625 return i;
626 }
627
628
629 static void __devinit sca_init(card_t *card, int wait_states)
630 {
631 sca_out(wait_states, WCRL, card); /* Wait Control */
632 sca_out(wait_states, WCRM, card);
633 sca_out(wait_states, WCRH, card);
634
635 sca_out(0, DMER, card); /* DMA Master disable */
636 sca_out(0x03, PCR, card); /* DMA priority */
637 sca_out(0, DSR_RX(0), card); /* DMA disable - to halt state */
638 sca_out(0, DSR_TX(0), card);
639 sca_out(0, DSR_RX(1), card);
640 sca_out(0, DSR_TX(1), card);
641 sca_out(DMER_DME, DMER, card); /* DMA Master enable */
642 }
linux-next