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(dev: 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(dev: 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, desc: i, transmit);
166 u16 chain_off = desc_offset(port, desc: i + 1, transmit);
167 u32 buff_off = buffer_offset(port, desc: i, transmit);
168
169 writew(val: chain_off, addr: &desc->cp);
170 writel(val: buff_off, addr: &desc->bp);
171 writew(val: 0, addr: &desc->len);
172 writeb(val: 0, addr: &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(addr: &desc->len);
248 skb = dev_alloc_skb(length: len);
249 if (!skb) {
250 dev->stats.rx_dropped++;
251 return;
252 }
253
254 buff = buffer_offset(port, desc: rxin, transmit: 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: 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, desc: port->rxin, transmit: 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, desc: port->rxin, transmit: 0);
308 stat = readb(addr: &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, rxin: port->rxin);
324 }
325
326 /* Set new error descriptor address */
327 sca_outw(desc_off, dmac + EDAL, card);
328 port->rxin = next_desc(port, desc: port->rxin, transmit: 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(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, desc: port->txlast, transmit: 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, desc: port->txlast, transmit: 1);
361 dev->stats.tx_packets++;
362 dev->stats.tx_bytes += readw(addr: &desc->len);
363 writeb(val: 0, addr: &desc->stat); /* Free descriptor */
364 port->txlast = next_desc(port, desc: port->txlast, transmit: 1);
365 }
366
367 netif_wake_queue(dev);
368 spin_unlock(lock: &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(lock: &port->lock);
636
637 desc = desc_address(port, desc: port->txin + 1, transmit: 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, desc: port->txin, transmit: 1);
646 buff = buffer_offset(port, desc: port->txin, transmit: 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: 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(val: len, addr: &desc->len);
665 writeb(ST_TX_EOM, addr: &desc->stat);
666
667 port->txin = next_desc(port, desc: port->txin, transmit: 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, desc: port->txin + 1, transmit: 1);
674 if (readb(addr: &desc->stat)) /* allow 1 packet gap */
675 netif_stop_queue(dev);
676
677 spin_unlock_irq(lock: &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

source code of linux/drivers/net/wan/hd64570.c