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
;
85 static inline u16
desc_offset(port_t
*port
, u16 desc
, int transmit
)
87 /* Descriptor offset always fits in 16 bits */
88 return desc_abs_number(port
, desc
, transmit
) * sizeof(pkt_desc
);
92 static inline pkt_desc __iomem
*desc_address(port_t
*port
, u16 desc
,
95 return (pkt_desc __iomem
*)(port
->card
->rambase
+
96 desc_offset(port
, desc
, transmit
));
100 static inline u32
buffer_offset(port_t
*port
, u16 desc
, int transmit
)
102 return port
->card
->buff_offset
+
103 desc_abs_number(port
, desc
, transmit
) * (u32
)HDLC_MAX_MRU
;
107 static inline void sca_set_carrier(port_t
*port
)
109 if (!(sca_in(get_msci(port
) + ST3
, port
->card
) & ST3_DCD
)) {
111 printk(KERN_DEBUG
"%s: sca_set_carrier on\n",
114 netif_carrier_on(port
->netdev
);
117 printk(KERN_DEBUG
"%s: sca_set_carrier off\n",
120 netif_carrier_off(port
->netdev
);
125 static void sca_init_port(port_t
*port
)
127 card_t
*card
= port
->card
;
128 u16 dmac_rx
= get_dmac_rx(port
), dmac_tx
= get_dmac_tx(port
);
135 for (transmit
= 0; transmit
< 2; transmit
++) {
136 u16 buffs
= transmit
? card
->tx_ring_buffers
137 : card
->rx_ring_buffers
;
139 for (i
= 0; i
< buffs
; i
++) {
140 pkt_desc __iomem
*desc
= desc_address(port
, i
, transmit
);
141 u16 chain_off
= desc_offset(port
, i
+ 1, transmit
);
142 u32 buff_off
= buffer_offset(port
, i
, transmit
);
144 writel(chain_off
, &desc
->cp
);
145 writel(buff_off
, &desc
->bp
);
146 writew(0, &desc
->len
);
147 writeb(0, &desc
->stat
);
151 /* DMA disable - to halt state */
152 sca_out(0, DSR_RX(port
->chan
), card
);
153 sca_out(0, DSR_TX(port
->chan
), card
);
155 /* software ABORT - to initial state */
156 sca_out(DCR_ABORT
, DCR_RX(port
->chan
), card
);
157 sca_out(DCR_ABORT
, DCR_TX(port
->chan
), card
);
159 /* current desc addr */
160 sca_outl(desc_offset(port
, 0, 0), dmac_rx
+ CDAL
, card
);
161 sca_outl(desc_offset(port
, card
->tx_ring_buffers
- 1, 0),
162 dmac_rx
+ EDAL
, card
);
163 sca_outl(desc_offset(port
, 0, 1), dmac_tx
+ CDAL
, card
);
164 sca_outl(desc_offset(port
, 0, 1), dmac_tx
+ EDAL
, card
);
166 /* clear frame end interrupt counter */
167 sca_out(DCR_CLEAR_EOF
, DCR_RX(port
->chan
), card
);
168 sca_out(DCR_CLEAR_EOF
, DCR_TX(port
->chan
), card
);
171 sca_outw(HDLC_MAX_MRU
, dmac_rx
+ BFLL
, card
); /* set buffer length */
172 sca_out(0x14, DMR_RX(port
->chan
), card
); /* Chain mode, Multi-frame */
173 sca_out(DIR_EOME
, DIR_RX(port
->chan
), card
); /* enable interrupts */
174 sca_out(DSR_DE
, DSR_RX(port
->chan
), card
); /* DMA enable */
177 sca_out(0x14, DMR_TX(port
->chan
), card
); /* Chain mode, Multi-frame */
178 sca_out(DIR_EOME
, DIR_TX(port
->chan
), card
); /* enable interrupts */
180 sca_set_carrier(port
);
181 netif_napi_add(port
->netdev
, &port
->napi
, sca_poll
, NAPI_WEIGHT
);
185 /* MSCI interrupt service */
186 static inline void sca_msci_intr(port_t
*port
)
188 u16 msci
= get_msci(port
);
189 card_t
* card
= port
->card
;
191 if (sca_in(msci
+ ST1
, card
) & ST1_CDCD
) {
192 /* Reset MSCI CDCD status bit */
193 sca_out(ST1_CDCD
, msci
+ ST1
, card
);
194 sca_set_carrier(port
);
199 static inline void sca_rx(card_t
*card
, port_t
*port
, pkt_desc __iomem
*desc
,
202 struct net_device
*dev
= port
->netdev
;
207 len
= readw(&desc
->len
);
208 skb
= dev_alloc_skb(len
);
210 dev
->stats
.rx_dropped
++;
214 buff
= buffer_offset(port
, rxin
, 0);
215 memcpy_fromio(skb
->data
, card
->rambase
+ buff
, len
);
219 printk(KERN_DEBUG
"%s RX(%i):", dev
->name
, skb
->len
);
222 dev
->stats
.rx_packets
++;
223 dev
->stats
.rx_bytes
+= skb
->len
;
224 skb
->protocol
= hdlc_type_trans(skb
, dev
);
225 netif_receive_skb(skb
);
229 /* Receive DMA service */
230 static inline int sca_rx_done(port_t
*port
, int budget
)
232 struct net_device
*dev
= port
->netdev
;
233 u16 dmac
= get_dmac_rx(port
);
234 card_t
*card
= port
->card
;
235 u8 stat
= sca_in(DSR_RX(port
->chan
), card
); /* read DMA Status */
238 /* Reset DSR status bits */
239 sca_out((stat
& (DSR_EOT
| DSR_EOM
| DSR_BOF
| DSR_COF
)) | DSR_DWE
,
240 DSR_RX(port
->chan
), card
);
243 /* Dropped one or more frames */
244 dev
->stats
.rx_over_errors
++;
246 while (received
< budget
) {
247 u32 desc_off
= desc_offset(port
, port
->rxin
, 0);
248 pkt_desc __iomem
*desc
;
249 u32 cda
= sca_inl(dmac
+ CDAL
, card
);
251 if ((cda
>= desc_off
) && (cda
< desc_off
+ sizeof(pkt_desc
)))
252 break; /* No frame received */
254 desc
= desc_address(port
, port
->rxin
, 0);
255 stat
= readb(&desc
->stat
);
256 if (!(stat
& ST_RX_EOM
))
257 port
->rxpart
= 1; /* partial frame received */
258 else if ((stat
& ST_ERROR_MASK
) || port
->rxpart
) {
259 dev
->stats
.rx_errors
++;
260 if (stat
& ST_RX_OVERRUN
)
261 dev
->stats
.rx_fifo_errors
++;
262 else if ((stat
& (ST_RX_SHORT
| ST_RX_ABORT
|
263 ST_RX_RESBIT
)) || port
->rxpart
)
264 dev
->stats
.rx_frame_errors
++;
265 else if (stat
& ST_RX_CRC
)
266 dev
->stats
.rx_crc_errors
++;
267 if (stat
& ST_RX_EOM
)
268 port
->rxpart
= 0; /* received last fragment */
270 sca_rx(card
, port
, desc
, port
->rxin
);
274 /* Set new error descriptor address */
275 sca_outl(desc_off
, dmac
+ EDAL
, card
);
276 port
->rxin
= (port
->rxin
+ 1) % card
->rx_ring_buffers
;
279 /* make sure RX DMA is enabled */
280 sca_out(DSR_DE
, DSR_RX(port
->chan
), card
);
285 /* Transmit DMA service */
286 static inline void sca_tx_done(port_t
*port
)
288 struct net_device
*dev
= port
->netdev
;
289 card_t
* card
= port
->card
;
293 spin_lock(&port
->lock
);
295 stat
= sca_in(DSR_TX(port
->chan
), card
); /* read DMA Status */
297 /* Reset DSR status bits */
298 sca_out((stat
& (DSR_EOT
| DSR_EOM
| DSR_BOF
| DSR_COF
)) | DSR_DWE
,
299 DSR_TX(port
->chan
), card
);
302 pkt_desc __iomem
*desc
= desc_address(port
, port
->txlast
, 1);
303 u8 stat
= readb(&desc
->stat
);
305 if (!(stat
& ST_TX_OWNRSHP
))
306 break; /* not yet transmitted */
307 if (stat
& ST_TX_UNDRRUN
) {
308 dev
->stats
.tx_errors
++;
309 dev
->stats
.tx_fifo_errors
++;
311 dev
->stats
.tx_packets
++;
312 dev
->stats
.tx_bytes
+= readw(&desc
->len
);
314 writeb(0, &desc
->stat
); /* Free descriptor */
316 port
->txlast
= (port
->txlast
+ 1) % card
->tx_ring_buffers
;
320 netif_wake_queue(dev
);
321 spin_unlock(&port
->lock
);
325 static int sca_poll(struct napi_struct
*napi
, int budget
)
327 port_t
*port
= container_of(napi
, port_t
, napi
);
328 u32 isr0
= sca_inl(ISR0
, port
->card
);
331 if (isr0
& (port
->chan
? 0x08000000 : 0x00080000))
334 if (isr0
& (port
->chan
? 0x00002000 : 0x00000020))
337 if (isr0
& (port
->chan
? 0x00000200 : 0x00000002))
338 received
= sca_rx_done(port
, budget
);
340 if (received
< budget
) {
341 napi_complete_done(napi
, received
);
348 static irqreturn_t
sca_intr(int irq
, void *dev_id
)
350 card_t
*card
= dev_id
;
351 u32 isr0
= sca_inl(ISR0
, card
);
354 for (i
= 0; i
< 2; i
++) {
355 port_t
*port
= get_port(card
, i
);
356 if (port
&& (isr0
& (i
? 0x08002200 : 0x00080022))) {
359 napi_schedule(&port
->napi
);
363 return IRQ_RETVAL(handled
);
367 static void sca_set_port(port_t
*port
)
369 card_t
* card
= port
->card
;
370 u16 msci
= get_msci(port
);
371 u8 md2
= sca_in(msci
+ MD2
, card
);
372 unsigned int tmc
, br
= 10, brv
= 1024;
375 if (port
->settings
.clock_rate
> 0) {
376 /* Try lower br for better accuracy*/
379 brv
>>= 1; /* brv = 2^9 = 512 max in specs */
381 /* Baud Rate = CLOCK_BASE / TMC / 2^BR */
382 tmc
= CLOCK_BASE
/ brv
/ port
->settings
.clock_rate
;
383 }while (br
> 1 && tmc
<= 128);
387 br
= 0; /* For baud=CLOCK_BASE we use tmc=1 br=0 */
389 } else if (tmc
> 255)
390 tmc
= 256; /* tmc=0 means 256 - low baud rates */
392 port
->settings
.clock_rate
= CLOCK_BASE
/ brv
/ tmc
;
394 br
= 9; /* Minimum clock rate */
395 tmc
= 256; /* 8bit = 0 */
396 port
->settings
.clock_rate
= CLOCK_BASE
/ (256 * 512);
399 port
->rxs
= (port
->rxs
& ~CLK_BRG_MASK
) | br
;
400 port
->txs
= (port
->txs
& ~CLK_BRG_MASK
) | br
;
403 /* baud divisor - time constant*/
404 sca_out(port
->tmc
, msci
+ TMCR
, card
);
405 sca_out(port
->tmc
, msci
+ TMCT
, card
);
408 sca_out(port
->rxs
, msci
+ RXS
, card
);
409 sca_out(port
->txs
, msci
+ TXS
, card
);
411 if (port
->settings
.loopback
)
414 md2
&= ~MD2_LOOPBACK
;
416 sca_out(md2
, msci
+ MD2
, card
);
421 static void sca_open(struct net_device
*dev
)
423 port_t
*port
= dev_to_port(dev
);
424 card_t
* card
= port
->card
;
425 u16 msci
= get_msci(port
);
428 switch(port
->encoding
) {
429 case ENCODING_NRZ
: md2
= MD2_NRZ
; break;
430 case ENCODING_NRZI
: md2
= MD2_NRZI
; break;
431 case ENCODING_FM_MARK
: md2
= MD2_FM_MARK
; break;
432 case ENCODING_FM_SPACE
: md2
= MD2_FM_SPACE
; break;
433 default: md2
= MD2_MANCHESTER
;
436 if (port
->settings
.loopback
)
439 switch(port
->parity
) {
440 case PARITY_CRC16_PR0
: md0
= MD0_HDLC
| MD0_CRC_16_0
; break;
441 case PARITY_CRC16_PR1
: md0
= MD0_HDLC
| MD0_CRC_16
; break;
442 case PARITY_CRC32_PR1_CCITT
: md0
= MD0_HDLC
| MD0_CRC_ITU32
; break;
443 case PARITY_CRC16_PR1_CCITT
: md0
= MD0_HDLC
| MD0_CRC_ITU
; break;
444 default: md0
= MD0_HDLC
| MD0_CRC_NONE
;
447 sca_out(CMD_RESET
, msci
+ CMD
, card
);
448 sca_out(md0
, msci
+ MD0
, card
);
449 sca_out(0x00, msci
+ MD1
, card
); /* no address field check */
450 sca_out(md2
, msci
+ MD2
, card
);
451 sca_out(0x7E, msci
+ IDL
, card
); /* flag character 0x7E */
452 /* Skip the rest of underrun frame */
453 sca_out(CTL_IDLE
| CTL_URCT
| CTL_URSKP
, msci
+ CTL
, card
);
454 sca_out(0x0F, msci
+ RNR
, card
); /* +1=RX DMA activation condition */
455 sca_out(0x3C, msci
+ TFS
, card
); /* +1 = TX start */
456 sca_out(0x38, msci
+ TCR
, card
); /* =Critical TX DMA activ condition */
457 sca_out(0x38, msci
+ TNR0
, card
); /* =TX DMA activation condition */
458 sca_out(0x3F, msci
+ TNR1
, card
); /* +1=TX DMA deactivation condition*/
460 /* We're using the following interrupts:
461 - RXINTA (DCD changes only)
462 - DMIB (EOM - single frame transfer complete)
464 sca_outl(IE0_RXINTA
| IE0_CDCD
, msci
+ IE0
, card
);
466 sca_out(port
->tmc
, msci
+ TMCR
, card
);
467 sca_out(port
->tmc
, msci
+ TMCT
, card
);
468 sca_out(port
->rxs
, msci
+ RXS
, card
);
469 sca_out(port
->txs
, msci
+ TXS
, card
);
470 sca_out(CMD_TX_ENABLE
, msci
+ CMD
, card
);
471 sca_out(CMD_RX_ENABLE
, msci
+ CMD
, card
);
473 sca_set_carrier(port
);
475 napi_enable(&port
->napi
);
476 netif_start_queue(dev
);
480 static void sca_close(struct net_device
*dev
)
482 port_t
*port
= dev_to_port(dev
);
485 sca_out(CMD_RESET
, get_msci(port
) + CMD
, port
->card
);
487 napi_disable(&port
->napi
);
488 netif_stop_queue(dev
);
492 static int sca_attach(struct net_device
*dev
, unsigned short encoding
,
493 unsigned short parity
)
495 if (encoding
!= ENCODING_NRZ
&&
496 encoding
!= ENCODING_NRZI
&&
497 encoding
!= ENCODING_FM_MARK
&&
498 encoding
!= ENCODING_FM_SPACE
&&
499 encoding
!= ENCODING_MANCHESTER
)
502 if (parity
!= PARITY_NONE
&&
503 parity
!= PARITY_CRC16_PR0
&&
504 parity
!= PARITY_CRC16_PR1
&&
505 parity
!= PARITY_CRC32_PR1_CCITT
&&
506 parity
!= PARITY_CRC16_PR1_CCITT
)
509 dev_to_port(dev
)->encoding
= encoding
;
510 dev_to_port(dev
)->parity
= parity
;
516 static void sca_dump_rings(struct net_device
*dev
)
518 port_t
*port
= dev_to_port(dev
);
519 card_t
*card
= port
->card
;
522 printk(KERN_DEBUG
"RX ring: CDA=%u EDA=%u DSR=%02X in=%u %sactive",
523 sca_inl(get_dmac_rx(port
) + CDAL
, card
),
524 sca_inl(get_dmac_rx(port
) + EDAL
, card
),
525 sca_in(DSR_RX(port
->chan
), card
), port
->rxin
,
526 sca_in(DSR_RX(port
->chan
), card
) & DSR_DE
? "" : "in");
527 for (cnt
= 0; cnt
< port
->card
->rx_ring_buffers
; cnt
++)
528 pr_cont(" %02X", readb(&(desc_address(port
, cnt
, 0)->stat
)));
531 printk(KERN_DEBUG
"TX ring: CDA=%u EDA=%u DSR=%02X in=%u "
533 sca_inl(get_dmac_tx(port
) + CDAL
, card
),
534 sca_inl(get_dmac_tx(port
) + EDAL
, card
),
535 sca_in(DSR_TX(port
->chan
), card
), port
->txin
, port
->txlast
,
536 sca_in(DSR_TX(port
->chan
), card
) & DSR_DE
? "" : "in");
538 for (cnt
= 0; cnt
< port
->card
->tx_ring_buffers
; cnt
++)
539 pr_cont(" %02X", readb(&(desc_address(port
, cnt
, 1)->stat
)));
542 printk(KERN_DEBUG
"MSCI: MD: %02x %02x %02x,"
543 " ST: %02x %02x %02x %02x %02x, FST: %02x CST: %02x %02x\n",
544 sca_in(get_msci(port
) + MD0
, card
),
545 sca_in(get_msci(port
) + MD1
, card
),
546 sca_in(get_msci(port
) + MD2
, card
),
547 sca_in(get_msci(port
) + ST0
, card
),
548 sca_in(get_msci(port
) + ST1
, card
),
549 sca_in(get_msci(port
) + ST2
, card
),
550 sca_in(get_msci(port
) + ST3
, card
),
551 sca_in(get_msci(port
) + ST4
, card
),
552 sca_in(get_msci(port
) + FST
, card
),
553 sca_in(get_msci(port
) + CST0
, card
),
554 sca_in(get_msci(port
) + CST1
, card
));
556 printk(KERN_DEBUG
"ILAR: %02x ISR: %08x %08x\n", sca_in(ILAR
, card
),
557 sca_inl(ISR0
, card
), sca_inl(ISR1
, card
));
559 #endif /* DEBUG_RINGS */
562 static netdev_tx_t
sca_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
564 port_t
*port
= dev_to_port(dev
);
565 card_t
*card
= port
->card
;
566 pkt_desc __iomem
*desc
;
569 spin_lock_irq(&port
->lock
);
571 desc
= desc_address(port
, port
->txin
+ 1, 1);
572 BUG_ON(readb(&desc
->stat
)); /* previous xmit should stop queue */
575 printk(KERN_DEBUG
"%s TX(%i):", dev
->name
, skb
->len
);
579 desc
= desc_address(port
, port
->txin
, 1);
580 buff
= buffer_offset(port
, port
->txin
, 1);
582 memcpy_toio(card
->rambase
+ buff
, skb
->data
, len
);
584 writew(len
, &desc
->len
);
585 writeb(ST_TX_EOM
, &desc
->stat
);
587 port
->txin
= (port
->txin
+ 1) % card
->tx_ring_buffers
;
588 sca_outl(desc_offset(port
, port
->txin
, 1),
589 get_dmac_tx(port
) + EDAL
, card
);
591 sca_out(DSR_DE
, DSR_TX(port
->chan
), card
); /* Enable TX DMA */
593 desc
= desc_address(port
, port
->txin
+ 1, 1);
594 if (readb(&desc
->stat
)) /* allow 1 packet gap */
595 netif_stop_queue(dev
);
597 spin_unlock_irq(&port
->lock
);
604 static u32
sca_detect_ram(card_t
*card
, u8 __iomem
*rambase
, u32 ramsize
)
606 /* Round RAM size to 32 bits, fill from end to start */
607 u32 i
= ramsize
&= ~3;
611 writel(i
^ 0x12345678, rambase
+ i
);
614 for (i
= 0; i
< ramsize
; i
+= 4) {
615 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 */