1 // SPDX-License-Identifier: GPL-2.0-only
3 * SDL Inc. RISCom/N2 synchronous serial card driver for Linux
5 * Copyright (C) 1998-2003 Krzysztof Halasa <khc@pm.waw.pl>
7 * For information see <https://www.kernel.org/pub/linux/utils/net/hdlc/>
9 * Note: integrated CSU/DSU/DDS are not supported by this driver
11 * Sources of information:
12 * Hitachi HD64570 SCA User's Manual
13 * SDL Inc. PPP/HDLC/CISCO driver
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18 #include <linux/module.h>
19 #include <linux/kernel.h>
20 #include <linux/capability.h>
21 #include <linux/slab.h>
22 #include <linux/types.h>
23 #include <linux/fcntl.h>
25 #include <linux/string.h>
26 #include <linux/errno.h>
27 #include <linux/init.h>
28 #include <linux/ioport.h>
29 #include <linux/moduleparam.h>
30 #include <linux/netdevice.h>
31 #include <linux/hdlc.h>
35 static const char *version
= "SDL RISCom/N2 driver version: 1.15";
36 static const char *devname
= "RISCom/N2";
41 #define USE_WINDOWSIZE 16384
42 #define USE_BUS16BITS 1
43 #define CLOCK_BASE 9830400 /* 9.8304 MHz */
44 #define MAX_PAGES 16 /* 16 RAM pages at max */
45 #define MAX_RAM_SIZE 0x80000 /* 512 KB */
46 #if MAX_RAM_SIZE > MAX_PAGES * USE_WINDOWSIZE
48 #define MAX_RAM_SIZE (MAX_PAGES * USE_WINDOWSIZE)
50 #define N2_IOPORTS 0x10
51 #define NEED_DETECT_RAM
52 #define NEED_SCA_MSCI_INTR
53 #define MAX_TX_BUFFERS 10
55 static char *hw
; /* pointer to hw=xxx command line string */
57 /* RISCom/N2 Board Registers */
59 /* PC Control Register */
61 #define PCR_RUNSCA 1 /* Run 64570 */
62 #define PCR_VPM 2 /* Enable VPM - needed if using RAM above 1 MB */
63 #define PCR_ENWIN 4 /* Open window */
64 #define PCR_BUS16 8 /* 16-bit bus */
66 /* Memory Base Address Register */
69 /* Page Scan Register */
74 #define PSR_WINBITS 0x60
75 #define PSR_DMAEN 0x80
76 #define PSR_PAGEBITS 0x0F
78 /* Modem Control Reg */
80 #define CLOCK_OUT_PORT1 0x80
81 #define CLOCK_OUT_PORT0 0x40
82 #define TX422_PORT1 0x20
83 #define TX422_PORT0 0x10
84 #define DSR_PORT1 0x08
85 #define DSR_PORT0 0x04
86 #define DTR_PORT1 0x02
87 #define DTR_PORT0 0x01
89 typedef struct port_s
{
90 struct net_device
*dev
;
92 spinlock_t lock
; /* TX lock */
93 sync_serial_settings settings
;
94 int valid
; /* port enabled */
95 int rxpart
; /* partial frame received, next frame invalid*/
96 unsigned short encoding
;
97 unsigned short parity
;
98 u16 rxin
; /* rx ring buffer 'in' pointer */
99 u16 txin
; /* tx ring buffer 'in' and 'last' pointers */
101 u8 rxs
, txs
, tmc
; /* SCA registers */
102 u8 phy_node
; /* physical port # - 0 or 1 */
103 u8 log_node
; /* logical port # */
106 typedef struct card_s
{
107 u8 __iomem
*winbase
; /* ISA window base address */
108 u32 phy_winbase
; /* ISA physical base address */
109 u32 ram_size
; /* number of bytes */
110 u16 io
; /* IO Base address */
111 u16 buff_offset
; /* offset of first buffer of first channel */
112 u16 rx_ring_buffers
; /* number of buffers in a ring */
114 u8 irq
; /* IRQ (3-15) */
117 struct card_s
*next_card
;
120 static card_t
*first_card
;
121 static card_t
**new_card
= &first_card
;
123 #define sca_reg(reg, card) (0x8000 | (card)->io | \
124 ((reg) & 0x0F) | (((reg) & 0xF0) << 6))
125 #define sca_in(reg, card) inb(sca_reg(reg, card))
126 #define sca_out(value, reg, card) outb(value, sca_reg(reg, card))
127 #define sca_inw(reg, card) inw(sca_reg(reg, card))
128 #define sca_outw(value, reg, card) outw(value, sca_reg(reg, card))
130 #define port_to_card(port) ((port)->card)
131 #define log_node(port) ((port)->log_node)
132 #define phy_node(port) ((port)->phy_node)
133 #define winsize(card) (USE_WINDOWSIZE)
134 #define winbase(card) ((card)->winbase)
135 #define get_port(card, port) ((card)->ports[port].valid ? \
136 &(card)->ports[port] : NULL)
138 static __inline__ u8
sca_get_page(card_t
*card
)
140 return inb(card
->io
+ N2_PSR
) & PSR_PAGEBITS
;
143 static __inline__
void openwin(card_t
*card
, u8 page
)
145 u8 psr
= inb(card
->io
+ N2_PSR
);
147 outb((psr
& ~PSR_PAGEBITS
) | page
, card
->io
+ N2_PSR
);
152 static void n2_set_iface(port_t
*port
)
154 card_t
*card
= port
->card
;
156 u8 mcr
= inb(io
+ N2_MCR
);
157 u8 msci
= get_msci(port
);
158 u8 rxs
= port
->rxs
& CLK_BRG_MASK
;
159 u8 txs
= port
->txs
& CLK_BRG_MASK
;
161 switch (port
->settings
.clock_type
) {
163 mcr
|= port
->phy_node
? CLOCK_OUT_PORT1
: CLOCK_OUT_PORT0
;
164 rxs
|= CLK_BRG_RX
; /* BRG output */
165 txs
|= CLK_RXCLK_TX
; /* RX clock */
169 mcr
|= port
->phy_node
? CLOCK_OUT_PORT1
: CLOCK_OUT_PORT0
;
170 rxs
|= CLK_LINE_RX
; /* RXC input */
171 txs
|= CLK_BRG_TX
; /* BRG output */
175 mcr
|= port
->phy_node
? CLOCK_OUT_PORT1
: CLOCK_OUT_PORT0
;
176 rxs
|= CLK_LINE_RX
; /* RXC input */
177 txs
|= CLK_RXCLK_TX
; /* RX clock */
180 default: /* Clock EXTernal */
181 mcr
&= port
->phy_node
? ~CLOCK_OUT_PORT1
: ~CLOCK_OUT_PORT0
;
182 rxs
|= CLK_LINE_RX
; /* RXC input */
183 txs
|= CLK_LINE_TX
; /* TXC input */
186 outb(mcr
, io
+ N2_MCR
);
189 sca_out(rxs
, msci
+ RXS
, card
);
190 sca_out(txs
, msci
+ TXS
, card
);
194 static int n2_open(struct net_device
*dev
)
196 port_t
*port
= dev_to_port(dev
);
197 int io
= port
->card
->io
;
198 u8 mcr
= inb(io
+ N2_MCR
) |
199 (port
->phy_node
? TX422_PORT1
: TX422_PORT0
);
202 result
= hdlc_open(dev
);
206 mcr
&= port
->phy_node
? ~DTR_PORT1
: ~DTR_PORT0
; /* set DTR ON */
207 outb(mcr
, io
+ N2_MCR
);
209 outb(inb(io
+ N2_PCR
) | PCR_ENWIN
, io
+ N2_PCR
); /* open window */
210 outb(inb(io
+ N2_PSR
) | PSR_DMAEN
, io
+ N2_PSR
); /* enable dma */
216 static int n2_close(struct net_device
*dev
)
218 port_t
*port
= dev_to_port(dev
);
219 int io
= port
->card
->io
;
220 u8 mcr
= inb(io
+ N2_MCR
) |
221 (port
->phy_node
? TX422_PORT1
: TX422_PORT0
);
224 mcr
|= port
->phy_node
? DTR_PORT1
: DTR_PORT0
; /* set DTR OFF */
225 outb(mcr
, io
+ N2_MCR
);
230 static int n2_siocdevprivate(struct net_device
*dev
, struct ifreq
*ifr
,
231 void __user
*data
, int cmd
)
234 if (cmd
== SIOCDEVPRIVATE
) {
242 static int n2_ioctl(struct net_device
*dev
, struct if_settings
*ifs
)
244 const size_t size
= sizeof(sync_serial_settings
);
245 sync_serial_settings new_line
;
246 sync_serial_settings __user
*line
= ifs
->ifs_ifsu
.sync
;
247 port_t
*port
= dev_to_port(dev
);
251 ifs
->type
= IF_IFACE_SYNC_SERIAL
;
252 if (ifs
->size
< size
) {
253 ifs
->size
= size
; /* data size wanted */
256 if (copy_to_user(line
, &port
->settings
, size
))
260 case IF_IFACE_SYNC_SERIAL
:
261 if (!capable(CAP_NET_ADMIN
))
264 if (copy_from_user(&new_line
, line
, size
))
267 if (new_line
.clock_type
!= CLOCK_EXT
&&
268 new_line
.clock_type
!= CLOCK_TXFROMRX
&&
269 new_line
.clock_type
!= CLOCK_INT
&&
270 new_line
.clock_type
!= CLOCK_TXINT
)
271 return -EINVAL
; /* No such clock setting */
273 if (new_line
.loopback
!= 0 && new_line
.loopback
!= 1)
276 memcpy(&port
->settings
, &new_line
, size
); /* Update settings */
281 return hdlc_ioctl(dev
, ifs
);
285 static void n2_destroy_card(card_t
*card
)
289 for (cnt
= 0; cnt
< 2; cnt
++)
290 if (card
->ports
[cnt
].card
) {
291 struct net_device
*dev
= port_to_dev(&card
->ports
[cnt
]);
293 unregister_hdlc_device(dev
);
297 free_irq(card
->irq
, card
);
300 iounmap(card
->winbase
);
301 release_mem_region(card
->phy_winbase
, USE_WINDOWSIZE
);
305 release_region(card
->io
, N2_IOPORTS
);
306 if (card
->ports
[0].dev
)
307 free_netdev(card
->ports
[0].dev
);
308 if (card
->ports
[1].dev
)
309 free_netdev(card
->ports
[1].dev
);
313 static const struct net_device_ops n2_ops
= {
315 .ndo_stop
= n2_close
,
316 .ndo_start_xmit
= hdlc_start_xmit
,
317 .ndo_siocwandev
= n2_ioctl
,
318 .ndo_siocdevprivate
= n2_siocdevprivate
,
321 static int __init
n2_run(unsigned long io
, unsigned long irq
,
322 unsigned long winbase
, long valid0
, long valid1
)
328 if (io
< 0x200 || io
> 0x3FF || (io
% N2_IOPORTS
) != 0) {
329 pr_err("invalid I/O port value\n");
333 if (irq
< 3 || irq
> 15 || irq
== 6) /* FIXME */ {
334 pr_err("invalid IRQ value\n");
338 if (winbase
< 0xA0000 || winbase
> 0xFFFFF || (winbase
& 0xFFF) != 0) {
339 pr_err("invalid RAM value\n");
343 card
= kzalloc(sizeof(card_t
), GFP_KERNEL
);
347 card
->ports
[0].dev
= alloc_hdlcdev(&card
->ports
[0]);
348 card
->ports
[1].dev
= alloc_hdlcdev(&card
->ports
[1]);
349 if (!card
->ports
[0].dev
|| !card
->ports
[1].dev
) {
350 pr_err("unable to allocate memory\n");
351 n2_destroy_card(card
);
355 if (!request_region(io
, N2_IOPORTS
, devname
)) {
356 pr_err("I/O port region in use\n");
357 n2_destroy_card(card
);
362 if (request_irq(irq
, sca_intr
, 0, devname
, card
)) {
363 pr_err("could not allocate IRQ\n");
364 n2_destroy_card(card
);
369 if (!request_mem_region(winbase
, USE_WINDOWSIZE
, devname
)) {
370 pr_err("could not request RAM window\n");
371 n2_destroy_card(card
);
374 card
->phy_winbase
= winbase
;
375 card
->winbase
= ioremap(winbase
, USE_WINDOWSIZE
);
376 if (!card
->winbase
) {
377 pr_err("ioremap() failed\n");
378 n2_destroy_card(card
);
382 outb(0, io
+ N2_PCR
);
383 outb(winbase
>> 12, io
+ N2_BAR
);
385 switch (USE_WINDOWSIZE
) {
387 outb(WIN16K
, io
+ N2_PSR
);
391 outb(WIN32K
, io
+ N2_PSR
);
395 outb(WIN64K
, io
+ N2_PSR
);
399 pr_err("invalid window size\n");
400 n2_destroy_card(card
);
404 pcr
= PCR_ENWIN
| PCR_VPM
| (USE_BUS16BITS
? PCR_BUS16
: 0);
405 outb(pcr
, io
+ N2_PCR
);
407 card
->ram_size
= sca_detect_ram(card
, card
->winbase
, MAX_RAM_SIZE
);
409 /* number of TX + RX buffers for one port */
410 i
= card
->ram_size
/ ((valid0
+ valid1
) * (sizeof(pkt_desc
) +
413 card
->tx_ring_buffers
= min(i
/ 2, MAX_TX_BUFFERS
);
414 card
->rx_ring_buffers
= i
- card
->tx_ring_buffers
;
416 card
->buff_offset
= (valid0
+ valid1
) * sizeof(pkt_desc
) *
417 (card
->tx_ring_buffers
+ card
->rx_ring_buffers
);
419 pr_info("RISCom/N2 %u KB RAM, IRQ%u, using %u TX + %u RX packets rings\n",
420 card
->ram_size
/ 1024, card
->irq
,
421 card
->tx_ring_buffers
, card
->rx_ring_buffers
);
423 if (card
->tx_ring_buffers
< 1) {
424 pr_err("RAM test failed\n");
425 n2_destroy_card(card
);
429 pcr
|= PCR_RUNSCA
; /* run SCA */
430 outb(pcr
, io
+ N2_PCR
);
431 outb(0, io
+ N2_MCR
);
434 for (cnt
= 0; cnt
< 2; cnt
++) {
435 port_t
*port
= &card
->ports
[cnt
];
436 struct net_device
*dev
= port_to_dev(port
);
437 hdlc_device
*hdlc
= dev_to_hdlc(dev
);
439 if ((cnt
== 0 && !valid0
) || (cnt
== 1 && !valid1
))
442 port
->phy_node
= cnt
;
445 if ((cnt
== 1) && valid0
)
448 spin_lock_init(&port
->lock
);
450 dev
->mem_start
= winbase
;
451 dev
->mem_end
= winbase
+ USE_WINDOWSIZE
- 1;
452 dev
->tx_queue_len
= 50;
453 dev
->netdev_ops
= &n2_ops
;
454 hdlc
->attach
= sca_attach
;
455 hdlc
->xmit
= sca_xmit
;
456 port
->settings
.clock_type
= CLOCK_EXT
;
459 if (register_hdlc_device(dev
)) {
460 pr_warn("unable to register hdlc device\n");
462 n2_destroy_card(card
);
465 sca_init_port(port
); /* Set up SCA memory */
467 netdev_info(dev
, "RISCom/N2 node %d\n", port
->phy_node
);
471 new_card
= &card
->next_card
;
476 static int __init
n2_init(void)
480 pr_info("no card initialized\n");
482 return -EINVAL
; /* no parameters specified, abort */
485 pr_info("%s\n", version
);
488 unsigned long io
, irq
, ram
;
489 long valid
[2] = { 0, 0 }; /* Default = both ports disabled */
491 io
= simple_strtoul(hw
, &hw
, 0);
495 irq
= simple_strtoul(hw
, &hw
, 0);
499 ram
= simple_strtoul(hw
, &hw
, 0);
504 if (*hw
== '0' && !valid
[0])
505 valid
[0] = 1; /* Port 0 enabled */
506 else if (*hw
== '1' && !valid
[1])
507 valid
[1] = 1; /* Port 1 enabled */
513 if (!valid
[0] && !valid
[1])
514 break; /* at least one port must be used */
516 if (*hw
== ':' || *hw
== '\x0')
517 n2_run(io
, irq
, ram
, valid
[0], valid
[1]);
520 return first_card
? 0 : -EINVAL
;
521 } while (*hw
++ == ':');
523 pr_err("invalid hardware parameters\n");
524 return first_card
? 0 : -EINVAL
;
527 static void __exit
n2_cleanup(void)
529 card_t
*card
= first_card
;
534 card
= card
->next_card
;
535 n2_destroy_card(ptr
);
539 module_init(n2_init
);
540 module_exit(n2_cleanup
);
542 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
543 MODULE_DESCRIPTION("RISCom/N2 serial port driver");
544 MODULE_LICENSE("GPL v2");
545 module_param(hw
, charp
, 0444);
546 MODULE_PARM_DESC(hw
, "io,irq,ram,ports:io,irq,...");