1 // SPDX-License-Identifier: GPL-2.0-only
3 * Hitachi (now Renesas) SCA-II HD64572 driver for Linux
5 * Copyright (C) 1998-2008 Krzysztof Halasa <khc@pm.waw.pl>
7 * Source of information: HD64572 SCA-II User's Manual
9 * We use the following SCA memory map:
11 * Packet buffer descriptor rings - starting from card->rambase:
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)
17 * Packet data buffers - starting from card->rambase + 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)
24 #include <linux/bitops.h>
25 #include <linux/errno.h>
26 #include <linux/fcntl.h>
27 #include <linux/hdlc.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>
39 #include <linux/uaccess.h>
42 #define NAPI_WEIGHT 16
44 #define get_msci(port) ((port)->chan ? MSCI1_OFFSET : MSCI0_OFFSET)
45 #define get_dmac_rx(port) ((port)->chan ? DMAC1RX_OFFSET : DMAC0RX_OFFSET)
46 #define get_dmac_tx(port) ((port)->chan ? DMAC1TX_OFFSET : DMAC0TX_OFFSET)
48 #define sca_in(reg, card) readb((card)->scabase + (reg))
49 #define sca_out(value, reg, card) writeb(value, (card)->scabase + (reg))
50 #define sca_inw(reg, card) readw((card)->scabase + (reg))
51 #define sca_outw(value, reg, card) writew(value, (card)->scabase + (reg))
52 #define sca_inl(reg, card) readl((card)->scabase + (reg))
53 #define sca_outl(value, reg, card) writel(value, (card)->scabase + (reg))
55 static int sca_poll(struct napi_struct
*napi
, int budget
);
57 static inline port_t
*dev_to_port(struct net_device
*dev
)
59 return dev_to_hdlc(dev
)->priv
;
62 static inline void enable_intr(port_t
*port
)
64 /* enable DMIB and MSCI RXINTA interrupts */
65 sca_outl(sca_inl(IER0
, port
->card
) |
66 (port
->chan
? 0x08002200 : 0x00080022), IER0
, port
->card
);
69 static inline void disable_intr(port_t
*port
)
71 sca_outl(sca_inl(IER0
, port
->card
) &
72 (port
->chan
? 0x00FF00FF : 0xFF00FF00), IER0
, port
->card
);
75 static inline u16
desc_abs_number(port_t
*port
, u16 desc
, int transmit
)
77 u16 rx_buffs
= port
->card
->rx_ring_buffers
;
78 u16 tx_buffs
= port
->card
->tx_ring_buffers
;
80 desc
%= (transmit
? tx_buffs
: rx_buffs
); // called with "X + 1" etc.
81 return port
->chan
* (rx_buffs
+ tx_buffs
) + transmit
* rx_buffs
+ desc
;
84 static inline u16
desc_offset(port_t
*port
, u16 desc
, int transmit
)
86 /* Descriptor offset always fits in 16 bits */
87 return desc_abs_number(port
, desc
, transmit
) * sizeof(pkt_desc
);
90 static inline pkt_desc __iomem
*desc_address(port_t
*port
, u16 desc
,
93 return (pkt_desc __iomem
*)(port
->card
->rambase
+
94 desc_offset(port
, desc
, transmit
));
97 static inline u32
buffer_offset(port_t
*port
, u16 desc
, int transmit
)
99 return port
->card
->buff_offset
+
100 desc_abs_number(port
, desc
, transmit
) * (u32
)HDLC_MAX_MRU
;
103 static inline void sca_set_carrier(port_t
*port
)
105 if (!(sca_in(get_msci(port
) + ST3
, port
->card
) & ST3_DCD
)) {
107 printk(KERN_DEBUG
"%s: sca_set_carrier on\n",
110 netif_carrier_on(port
->netdev
);
113 printk(KERN_DEBUG
"%s: sca_set_carrier off\n",
116 netif_carrier_off(port
->netdev
);
120 static void sca_init_port(port_t
*port
)
122 card_t
*card
= port
->card
;
123 u16 dmac_rx
= get_dmac_rx(port
), dmac_tx
= get_dmac_tx(port
);
130 for (transmit
= 0; transmit
< 2; transmit
++) {
131 u16 buffs
= transmit
? card
->tx_ring_buffers
132 : card
->rx_ring_buffers
;
134 for (i
= 0; i
< buffs
; i
++) {
135 pkt_desc __iomem
*desc
= desc_address(port
, i
, transmit
);
136 u16 chain_off
= desc_offset(port
, i
+ 1, transmit
);
137 u32 buff_off
= buffer_offset(port
, i
, transmit
);
139 writel(chain_off
, &desc
->cp
);
140 writel(buff_off
, &desc
->bp
);
141 writew(0, &desc
->len
);
142 writeb(0, &desc
->stat
);
146 /* DMA disable - to halt state */
147 sca_out(0, DSR_RX(port
->chan
), card
);
148 sca_out(0, DSR_TX(port
->chan
), card
);
150 /* software ABORT - to initial state */
151 sca_out(DCR_ABORT
, DCR_RX(port
->chan
), card
);
152 sca_out(DCR_ABORT
, DCR_TX(port
->chan
), card
);
154 /* current desc addr */
155 sca_outl(desc_offset(port
, 0, 0), dmac_rx
+ CDAL
, card
);
156 sca_outl(desc_offset(port
, card
->tx_ring_buffers
- 1, 0),
157 dmac_rx
+ EDAL
, card
);
158 sca_outl(desc_offset(port
, 0, 1), dmac_tx
+ CDAL
, card
);
159 sca_outl(desc_offset(port
, 0, 1), dmac_tx
+ EDAL
, card
);
161 /* clear frame end interrupt counter */
162 sca_out(DCR_CLEAR_EOF
, DCR_RX(port
->chan
), card
);
163 sca_out(DCR_CLEAR_EOF
, DCR_TX(port
->chan
), card
);
166 sca_outw(HDLC_MAX_MRU
, dmac_rx
+ BFLL
, card
); /* set buffer length */
167 sca_out(0x14, DMR_RX(port
->chan
), card
); /* Chain mode, Multi-frame */
168 sca_out(DIR_EOME
, DIR_RX(port
->chan
), card
); /* enable interrupts */
169 sca_out(DSR_DE
, DSR_RX(port
->chan
), card
); /* DMA enable */
172 sca_out(0x14, DMR_TX(port
->chan
), card
); /* Chain mode, Multi-frame */
173 sca_out(DIR_EOME
, DIR_TX(port
->chan
), card
); /* enable interrupts */
175 sca_set_carrier(port
);
176 netif_napi_add_weight(port
->netdev
, &port
->napi
, sca_poll
,
180 /* MSCI interrupt service */
181 static inline void sca_msci_intr(port_t
*port
)
183 u16 msci
= get_msci(port
);
184 card_t
*card
= port
->card
;
186 if (sca_in(msci
+ ST1
, card
) & ST1_CDCD
) {
187 /* Reset MSCI CDCD status bit */
188 sca_out(ST1_CDCD
, msci
+ ST1
, card
);
189 sca_set_carrier(port
);
193 static inline void sca_rx(card_t
*card
, port_t
*port
, pkt_desc __iomem
*desc
,
196 struct net_device
*dev
= port
->netdev
;
201 len
= readw(&desc
->len
);
202 skb
= dev_alloc_skb(len
);
204 dev
->stats
.rx_dropped
++;
208 buff
= buffer_offset(port
, rxin
, 0);
209 memcpy_fromio(skb
->data
, card
->rambase
+ buff
, len
);
213 printk(KERN_DEBUG
"%s RX(%i):", dev
->name
, skb
->len
);
216 dev
->stats
.rx_packets
++;
217 dev
->stats
.rx_bytes
+= skb
->len
;
218 skb
->protocol
= hdlc_type_trans(skb
, dev
);
219 netif_receive_skb(skb
);
222 /* Receive DMA service */
223 static inline int sca_rx_done(port_t
*port
, int budget
)
225 struct net_device
*dev
= port
->netdev
;
226 u16 dmac
= get_dmac_rx(port
);
227 card_t
*card
= port
->card
;
228 u8 stat
= sca_in(DSR_RX(port
->chan
), card
); /* read DMA Status */
231 /* Reset DSR status bits */
232 sca_out((stat
& (DSR_EOT
| DSR_EOM
| DSR_BOF
| DSR_COF
)) | DSR_DWE
,
233 DSR_RX(port
->chan
), card
);
236 /* Dropped one or more frames */
237 dev
->stats
.rx_over_errors
++;
239 while (received
< budget
) {
240 u32 desc_off
= desc_offset(port
, port
->rxin
, 0);
241 pkt_desc __iomem
*desc
;
242 u32 cda
= sca_inl(dmac
+ CDAL
, card
);
244 if ((cda
>= desc_off
) && (cda
< desc_off
+ sizeof(pkt_desc
)))
245 break; /* No frame received */
247 desc
= desc_address(port
, port
->rxin
, 0);
248 stat
= readb(&desc
->stat
);
249 if (!(stat
& ST_RX_EOM
))
250 port
->rxpart
= 1; /* partial frame received */
251 else if ((stat
& ST_ERROR_MASK
) || port
->rxpart
) {
252 dev
->stats
.rx_errors
++;
253 if (stat
& ST_RX_OVERRUN
)
254 dev
->stats
.rx_fifo_errors
++;
255 else if ((stat
& (ST_RX_SHORT
| ST_RX_ABORT
|
256 ST_RX_RESBIT
)) || port
->rxpart
)
257 dev
->stats
.rx_frame_errors
++;
258 else if (stat
& ST_RX_CRC
)
259 dev
->stats
.rx_crc_errors
++;
260 if (stat
& ST_RX_EOM
)
261 port
->rxpart
= 0; /* received last fragment */
263 sca_rx(card
, port
, desc
, port
->rxin
);
267 /* Set new error descriptor address */
268 sca_outl(desc_off
, dmac
+ EDAL
, card
);
269 port
->rxin
= (port
->rxin
+ 1) % card
->rx_ring_buffers
;
272 /* make sure RX DMA is enabled */
273 sca_out(DSR_DE
, DSR_RX(port
->chan
), card
);
277 /* Transmit DMA service */
278 static inline void sca_tx_done(port_t
*port
)
280 struct net_device
*dev
= port
->netdev
;
281 card_t
*card
= port
->card
;
285 spin_lock(&port
->lock
);
287 stat
= sca_in(DSR_TX(port
->chan
), card
); /* read DMA Status */
289 /* Reset DSR status bits */
290 sca_out((stat
& (DSR_EOT
| DSR_EOM
| DSR_BOF
| DSR_COF
)) | DSR_DWE
,
291 DSR_TX(port
->chan
), card
);
294 pkt_desc __iomem
*desc
= desc_address(port
, port
->txlast
, 1);
295 u8 stat
= readb(&desc
->stat
);
297 if (!(stat
& ST_TX_OWNRSHP
))
298 break; /* not yet transmitted */
299 if (stat
& ST_TX_UNDRRUN
) {
300 dev
->stats
.tx_errors
++;
301 dev
->stats
.tx_fifo_errors
++;
303 dev
->stats
.tx_packets
++;
304 dev
->stats
.tx_bytes
+= readw(&desc
->len
);
306 writeb(0, &desc
->stat
); /* Free descriptor */
308 port
->txlast
= (port
->txlast
+ 1) % card
->tx_ring_buffers
;
312 netif_wake_queue(dev
);
313 spin_unlock(&port
->lock
);
316 static int sca_poll(struct napi_struct
*napi
, int budget
)
318 port_t
*port
= container_of(napi
, port_t
, napi
);
319 u32 isr0
= sca_inl(ISR0
, port
->card
);
322 if (isr0
& (port
->chan
? 0x08000000 : 0x00080000))
325 if (isr0
& (port
->chan
? 0x00002000 : 0x00000020))
328 if (isr0
& (port
->chan
? 0x00000200 : 0x00000002))
329 received
= sca_rx_done(port
, budget
);
331 if (received
< budget
) {
332 napi_complete_done(napi
, received
);
339 static irqreturn_t
sca_intr(int irq
, void *dev_id
)
341 card_t
*card
= dev_id
;
342 u32 isr0
= sca_inl(ISR0
, card
);
345 for (i
= 0; i
< 2; i
++) {
346 port_t
*port
= get_port(card
, i
);
347 if (port
&& (isr0
& (i
? 0x08002200 : 0x00080022))) {
350 napi_schedule(&port
->napi
);
354 return IRQ_RETVAL(handled
);
357 static void sca_set_port(port_t
*port
)
359 card_t
*card
= port
->card
;
360 u16 msci
= get_msci(port
);
361 u8 md2
= sca_in(msci
+ MD2
, card
);
362 unsigned int tmc
, br
= 10, brv
= 1024;
364 if (port
->settings
.clock_rate
> 0) {
365 /* Try lower br for better accuracy*/
368 brv
>>= 1; /* brv = 2^9 = 512 max in specs */
370 /* Baud Rate = CLOCK_BASE / TMC / 2^BR */
371 tmc
= CLOCK_BASE
/ brv
/ port
->settings
.clock_rate
;
372 } while (br
> 1 && tmc
<= 128);
376 br
= 0; /* For baud=CLOCK_BASE we use tmc=1 br=0 */
378 } else if (tmc
> 255) {
379 tmc
= 256; /* tmc=0 means 256 - low baud rates */
382 port
->settings
.clock_rate
= CLOCK_BASE
/ brv
/ tmc
;
384 br
= 9; /* Minimum clock rate */
385 tmc
= 256; /* 8bit = 0 */
386 port
->settings
.clock_rate
= CLOCK_BASE
/ (256 * 512);
389 port
->rxs
= (port
->rxs
& ~CLK_BRG_MASK
) | br
;
390 port
->txs
= (port
->txs
& ~CLK_BRG_MASK
) | br
;
393 /* baud divisor - time constant*/
394 sca_out(port
->tmc
, msci
+ TMCR
, card
);
395 sca_out(port
->tmc
, msci
+ TMCT
, card
);
398 sca_out(port
->rxs
, msci
+ RXS
, card
);
399 sca_out(port
->txs
, msci
+ TXS
, card
);
401 if (port
->settings
.loopback
)
404 md2
&= ~MD2_LOOPBACK
;
406 sca_out(md2
, msci
+ MD2
, card
);
409 static void sca_open(struct net_device
*dev
)
411 port_t
*port
= dev_to_port(dev
);
412 card_t
*card
= port
->card
;
413 u16 msci
= get_msci(port
);
416 switch (port
->encoding
) {
423 case ENCODING_FM_MARK
:
426 case ENCODING_FM_SPACE
:
430 md2
= MD2_MANCHESTER
;
433 if (port
->settings
.loopback
)
436 switch (port
->parity
) {
437 case PARITY_CRC16_PR0
:
438 md0
= MD0_HDLC
| MD0_CRC_16_0
;
440 case PARITY_CRC16_PR1
:
441 md0
= MD0_HDLC
| MD0_CRC_16
;
443 case PARITY_CRC32_PR1_CCITT
:
444 md0
= MD0_HDLC
| MD0_CRC_ITU32
;
446 case PARITY_CRC16_PR1_CCITT
:
447 md0
= MD0_HDLC
| MD0_CRC_ITU
;
450 md0
= MD0_HDLC
| MD0_CRC_NONE
;
453 sca_out(CMD_RESET
, msci
+ CMD
, card
);
454 sca_out(md0
, msci
+ MD0
, card
);
455 sca_out(0x00, msci
+ MD1
, card
); /* no address field check */
456 sca_out(md2
, msci
+ MD2
, card
);
457 sca_out(0x7E, msci
+ IDL
, card
); /* flag character 0x7E */
458 /* Skip the rest of underrun frame */
459 sca_out(CTL_IDLE
| CTL_URCT
| CTL_URSKP
, msci
+ CTL
, card
);
460 sca_out(0x0F, msci
+ RNR
, card
); /* +1=RX DMA activation condition */
461 sca_out(0x3C, msci
+ TFS
, card
); /* +1 = TX start */
462 sca_out(0x38, msci
+ TCR
, card
); /* =Critical TX DMA activ condition */
463 sca_out(0x38, msci
+ TNR0
, card
); /* =TX DMA activation condition */
464 sca_out(0x3F, msci
+ TNR1
, card
); /* +1=TX DMA deactivation condition*/
466 /* We're using the following interrupts:
467 - RXINTA (DCD changes only)
468 - DMIB (EOM - single frame transfer complete)
470 sca_outl(IE0_RXINTA
| IE0_CDCD
, msci
+ IE0
, card
);
472 sca_out(port
->tmc
, msci
+ TMCR
, card
);
473 sca_out(port
->tmc
, msci
+ TMCT
, card
);
474 sca_out(port
->rxs
, msci
+ RXS
, card
);
475 sca_out(port
->txs
, msci
+ TXS
, card
);
476 sca_out(CMD_TX_ENABLE
, msci
+ CMD
, card
);
477 sca_out(CMD_RX_ENABLE
, msci
+ CMD
, card
);
479 sca_set_carrier(port
);
481 napi_enable(&port
->napi
);
482 netif_start_queue(dev
);
485 static void sca_close(struct net_device
*dev
)
487 port_t
*port
= dev_to_port(dev
);
490 sca_out(CMD_RESET
, get_msci(port
) + CMD
, port
->card
);
492 napi_disable(&port
->napi
);
493 netif_stop_queue(dev
);
496 static int sca_attach(struct net_device
*dev
, unsigned short encoding
,
497 unsigned short parity
)
499 if (encoding
!= ENCODING_NRZ
&&
500 encoding
!= ENCODING_NRZI
&&
501 encoding
!= ENCODING_FM_MARK
&&
502 encoding
!= ENCODING_FM_SPACE
&&
503 encoding
!= ENCODING_MANCHESTER
)
506 if (parity
!= PARITY_NONE
&&
507 parity
!= PARITY_CRC16_PR0
&&
508 parity
!= PARITY_CRC16_PR1
&&
509 parity
!= PARITY_CRC32_PR1_CCITT
&&
510 parity
!= PARITY_CRC16_PR1_CCITT
)
513 dev_to_port(dev
)->encoding
= encoding
;
514 dev_to_port(dev
)->parity
= parity
;
519 static void sca_dump_rings(struct net_device
*dev
)
521 port_t
*port
= dev_to_port(dev
);
522 card_t
*card
= port
->card
;
525 printk(KERN_DEBUG
"RX ring: CDA=%u EDA=%u DSR=%02X in=%u %sactive",
526 sca_inl(get_dmac_rx(port
) + CDAL
, card
),
527 sca_inl(get_dmac_rx(port
) + EDAL
, card
),
528 sca_in(DSR_RX(port
->chan
), card
), port
->rxin
,
529 sca_in(DSR_RX(port
->chan
), card
) & DSR_DE
? "" : "in");
530 for (cnt
= 0; cnt
< port
->card
->rx_ring_buffers
; cnt
++)
531 pr_cont(" %02X", readb(&(desc_address(port
, cnt
, 0)->stat
)));
534 printk(KERN_DEBUG
"TX ring: CDA=%u EDA=%u DSR=%02X in=%u "
536 sca_inl(get_dmac_tx(port
) + CDAL
, card
),
537 sca_inl(get_dmac_tx(port
) + EDAL
, card
),
538 sca_in(DSR_TX(port
->chan
), card
), port
->txin
, port
->txlast
,
539 sca_in(DSR_TX(port
->chan
), card
) & DSR_DE
? "" : "in");
541 for (cnt
= 0; cnt
< port
->card
->tx_ring_buffers
; cnt
++)
542 pr_cont(" %02X", readb(&(desc_address(port
, cnt
, 1)->stat
)));
545 printk(KERN_DEBUG
"MSCI: MD: %02x %02x %02x,"
546 " ST: %02x %02x %02x %02x %02x, FST: %02x CST: %02x %02x\n",
547 sca_in(get_msci(port
) + MD0
, card
),
548 sca_in(get_msci(port
) + MD1
, card
),
549 sca_in(get_msci(port
) + MD2
, card
),
550 sca_in(get_msci(port
) + ST0
, card
),
551 sca_in(get_msci(port
) + ST1
, card
),
552 sca_in(get_msci(port
) + ST2
, card
),
553 sca_in(get_msci(port
) + ST3
, card
),
554 sca_in(get_msci(port
) + ST4
, card
),
555 sca_in(get_msci(port
) + FST
, card
),
556 sca_in(get_msci(port
) + CST0
, card
),
557 sca_in(get_msci(port
) + CST1
, card
));
559 printk(KERN_DEBUG
"ILAR: %02x ISR: %08x %08x\n", sca_in(ILAR
, card
),
560 sca_inl(ISR0
, card
), sca_inl(ISR1
, card
));
562 #endif /* DEBUG_RINGS */
564 static netdev_tx_t
sca_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
566 port_t
*port
= dev_to_port(dev
);
567 card_t
*card
= port
->card
;
568 pkt_desc __iomem
*desc
;
571 spin_lock_irq(&port
->lock
);
573 desc
= desc_address(port
, port
->txin
+ 1, 1);
574 BUG_ON(readb(&desc
->stat
)); /* previous xmit should stop queue */
577 printk(KERN_DEBUG
"%s TX(%i):", dev
->name
, skb
->len
);
581 desc
= desc_address(port
, port
->txin
, 1);
582 buff
= buffer_offset(port
, port
->txin
, 1);
584 memcpy_toio(card
->rambase
+ buff
, skb
->data
, len
);
586 writew(len
, &desc
->len
);
587 writeb(ST_TX_EOM
, &desc
->stat
);
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
);
593 sca_out(DSR_DE
, DSR_TX(port
->chan
), card
); /* Enable TX DMA */
595 desc
= desc_address(port
, port
->txin
+ 1, 1);
596 if (readb(&desc
->stat
)) /* allow 1 packet gap */
597 netif_stop_queue(dev
);
599 spin_unlock_irq(&port
->lock
);
605 static u32
sca_detect_ram(card_t
*card
, u8 __iomem
*rambase
, u32 ramsize
)
607 /* Round RAM size to 32 bits, fill from end to start */
608 u32 i
= ramsize
&= ~3;
612 writel(i
^ 0x12345678, rambase
+ i
);
615 for (i
= 0; i
< ramsize
; i
+= 4) {
616 if (readl(rambase
+ i
) != (i
^ 0x12345678))
623 static void sca_init(card_t
*card
, int wait_states
)
625 sca_out(wait_states
, WCRL
, card
); /* Wait Control */
626 sca_out(wait_states
, WCRM
, card
);
627 sca_out(wait_states
, WCRH
, card
);
629 sca_out(0, DMER
, card
); /* DMA Master disable */
630 sca_out(0x03, PCR
, card
); /* DMA priority */
631 sca_out(0, DSR_RX(0), card
); /* DMA disable - to halt state */
632 sca_out(0, DSR_TX(0), card
);
633 sca_out(0, DSR_RX(1), card
);
634 sca_out(0, DSR_TX(1), card
);
635 sca_out(DMER_DME
, DMER
, card
); /* DMA Master enable */