xref: /linux/drivers/net/wan/pc300too.c (revision 0d3b051adbb72ed81956447d0d1e54d5943ee6f5)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Cyclades PC300 synchronous serial card driver for Linux
4  *
5  * Copyright (C) 2000-2008 Krzysztof Halasa <khc@pm.waw.pl>
6  *
7  * For information see <https://www.kernel.org/pub/linux/utils/net/hdlc/>.
8  *
9  * Sources of information:
10  *    Hitachi HD64572 SCA-II User's Manual
11  *    Original Cyclades PC300 Linux driver
12  *
13  * This driver currently supports only PC300/RSV (V.24/V.35) and
14  * PC300/X21 cards.
15  */
16 
17 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18 
19 #include <linux/module.h>
20 #include <linux/kernel.h>
21 #include <linux/slab.h>
22 #include <linux/sched.h>
23 #include <linux/types.h>
24 #include <linux/fcntl.h>
25 #include <linux/in.h>
26 #include <linux/string.h>
27 #include <linux/errno.h>
28 #include <linux/init.h>
29 #include <linux/ioport.h>
30 #include <linux/moduleparam.h>
31 #include <linux/netdevice.h>
32 #include <linux/hdlc.h>
33 #include <linux/pci.h>
34 #include <linux/delay.h>
35 #include <asm/io.h>
36 
37 #include "hd64572.h"
38 
39 #undef DEBUG_PKT
40 #define DEBUG_RINGS
41 
42 #define PC300_PLX_SIZE		0x80    /* PLX control window size (128 B) */
43 #define PC300_SCA_SIZE		0x400   /* SCA window size (1 KB) */
44 #define MAX_TX_BUFFERS		10
45 
46 static int pci_clock_freq = 33000000;
47 static int use_crystal_clock = 0;
48 static unsigned int CLOCK_BASE;
49 
50 /* Masks to access the init_ctrl PLX register */
51 #define PC300_CLKSEL_MASK	 (0x00000004UL)
52 #define PC300_CHMEDIA_MASK(port) (0x00000020UL << ((port) * 3))
53 #define PC300_CTYPE_MASK	 (0x00000800UL)
54 
55 
56 enum { PC300_RSV = 1, PC300_X21, PC300_TE }; /* card types */
57 
58 /*
59  *      PLX PCI9050-1 local configuration and shared runtime registers.
60  *      This structure can be used to access 9050 registers (memory mapped).
61  */
62 typedef struct {
63 	u32 loc_addr_range[4];	/* 00-0Ch : Local Address Ranges */
64 	u32 loc_rom_range;	/* 10h : Local ROM Range */
65 	u32 loc_addr_base[4];	/* 14-20h : Local Address Base Addrs */
66 	u32 loc_rom_base;	/* 24h : Local ROM Base */
67 	u32 loc_bus_descr[4];	/* 28-34h : Local Bus Descriptors */
68 	u32 rom_bus_descr;	/* 38h : ROM Bus Descriptor */
69 	u32 cs_base[4];		/* 3C-48h : Chip Select Base Addrs */
70 	u32 intr_ctrl_stat;	/* 4Ch : Interrupt Control/Status */
71 	u32 init_ctrl;		/* 50h : EEPROM ctrl, Init Ctrl, etc */
72 }plx9050;
73 
74 
75 
76 typedef struct port_s {
77 	struct napi_struct napi;
78 	struct net_device *netdev;
79 	struct card_s *card;
80 	spinlock_t lock;	/* TX lock */
81 	sync_serial_settings settings;
82 	int rxpart;		/* partial frame received, next frame invalid*/
83 	unsigned short encoding;
84 	unsigned short parity;
85 	unsigned int iface;
86 	u16 rxin;		/* rx ring buffer 'in' pointer */
87 	u16 txin;		/* tx ring buffer 'in' and 'last' pointers */
88 	u16 txlast;
89 	u8 rxs, txs, tmc;	/* SCA registers */
90 	u8 chan;		/* physical port # - 0 or 1 */
91 }port_t;
92 
93 
94 
95 typedef struct card_s {
96 	int type;		/* RSV, X21, etc. */
97 	int n_ports;		/* 1 or 2 ports */
98 	u8 __iomem *rambase;	/* buffer memory base (virtual) */
99 	u8 __iomem *scabase;	/* SCA memory base (virtual) */
100 	plx9050 __iomem *plxbase; /* PLX registers memory base (virtual) */
101 	u32 init_ctrl_value;	/* Saved value - 9050 bug workaround */
102 	u16 rx_ring_buffers;	/* number of buffers in a ring */
103 	u16 tx_ring_buffers;
104 	u16 buff_offset;	/* offset of first buffer of first channel */
105 	u8 irq;			/* interrupt request level */
106 
107 	port_t ports[2];
108 }card_t;
109 
110 
111 #define get_port(card, port)	     ((port) < (card)->n_ports ? \
112 					 (&(card)->ports[port]) : (NULL))
113 
114 #include "hd64572.c"
115 
116 
117 static void pc300_set_iface(port_t *port)
118 {
119 	card_t *card = port->card;
120 	u32 __iomem * init_ctrl = &card->plxbase->init_ctrl;
121 	u16 msci = get_msci(port);
122 	u8 rxs = port->rxs & CLK_BRG_MASK;
123 	u8 txs = port->txs & CLK_BRG_MASK;
124 
125 	sca_out(EXS_TES1, (port->chan ? MSCI1_OFFSET : MSCI0_OFFSET) + EXS,
126 		port->card);
127 	switch(port->settings.clock_type) {
128 	case CLOCK_INT:
129 		rxs |= CLK_BRG; /* BRG output */
130 		txs |= CLK_PIN_OUT | CLK_TX_RXCLK; /* RX clock */
131 		break;
132 
133 	case CLOCK_TXINT:
134 		rxs |= CLK_LINE; /* RXC input */
135 		txs |= CLK_PIN_OUT | CLK_BRG; /* BRG output */
136 		break;
137 
138 	case CLOCK_TXFROMRX:
139 		rxs |= CLK_LINE; /* RXC input */
140 		txs |= CLK_PIN_OUT | CLK_TX_RXCLK; /* RX clock */
141 		break;
142 
143 	default:		/* EXTernal clock */
144 		rxs |= CLK_LINE; /* RXC input */
145 		txs |= CLK_PIN_OUT | CLK_LINE; /* TXC input */
146 		break;
147 	}
148 
149 	port->rxs = rxs;
150 	port->txs = txs;
151 	sca_out(rxs, msci + RXS, card);
152 	sca_out(txs, msci + TXS, card);
153 	sca_set_port(port);
154 
155 	if (port->card->type == PC300_RSV) {
156 		if (port->iface == IF_IFACE_V35)
157 			writel(card->init_ctrl_value |
158 			       PC300_CHMEDIA_MASK(port->chan), init_ctrl);
159 		else
160 			writel(card->init_ctrl_value &
161 			       ~PC300_CHMEDIA_MASK(port->chan), init_ctrl);
162 	}
163 }
164 
165 
166 
167 static int pc300_open(struct net_device *dev)
168 {
169 	port_t *port = dev_to_port(dev);
170 
171 	int result = hdlc_open(dev);
172 	if (result)
173 		return result;
174 
175 	sca_open(dev);
176 	pc300_set_iface(port);
177 	return 0;
178 }
179 
180 
181 
182 static int pc300_close(struct net_device *dev)
183 {
184 	sca_close(dev);
185 	hdlc_close(dev);
186 	return 0;
187 }
188 
189 
190 
191 static int pc300_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
192 {
193 	const size_t size = sizeof(sync_serial_settings);
194 	sync_serial_settings new_line;
195 	sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
196 	int new_type;
197 	port_t *port = dev_to_port(dev);
198 
199 #ifdef DEBUG_RINGS
200 	if (cmd == SIOCDEVPRIVATE) {
201 		sca_dump_rings(dev);
202 		return 0;
203 	}
204 #endif
205 	if (cmd != SIOCWANDEV)
206 		return hdlc_ioctl(dev, ifr, cmd);
207 
208 	if (ifr->ifr_settings.type == IF_GET_IFACE) {
209 		ifr->ifr_settings.type = port->iface;
210 		if (ifr->ifr_settings.size < size) {
211 			ifr->ifr_settings.size = size; /* data size wanted */
212 			return -ENOBUFS;
213 		}
214 		if (copy_to_user(line, &port->settings, size))
215 			return -EFAULT;
216 		return 0;
217 
218 	}
219 
220 	if (port->card->type == PC300_X21 &&
221 	    (ifr->ifr_settings.type == IF_IFACE_SYNC_SERIAL ||
222 	     ifr->ifr_settings.type == IF_IFACE_X21))
223 		new_type = IF_IFACE_X21;
224 
225 	else if (port->card->type == PC300_RSV &&
226 		 (ifr->ifr_settings.type == IF_IFACE_SYNC_SERIAL ||
227 		  ifr->ifr_settings.type == IF_IFACE_V35))
228 		new_type = IF_IFACE_V35;
229 
230 	else if (port->card->type == PC300_RSV &&
231 		 ifr->ifr_settings.type == IF_IFACE_V24)
232 		new_type = IF_IFACE_V24;
233 
234 	else
235 		return hdlc_ioctl(dev, ifr, cmd);
236 
237 	if (!capable(CAP_NET_ADMIN))
238 		return -EPERM;
239 
240 	if (copy_from_user(&new_line, line, size))
241 		return -EFAULT;
242 
243 	if (new_line.clock_type != CLOCK_EXT &&
244 	    new_line.clock_type != CLOCK_TXFROMRX &&
245 	    new_line.clock_type != CLOCK_INT &&
246 	    new_line.clock_type != CLOCK_TXINT)
247 		return -EINVAL;	/* No such clock setting */
248 
249 	if (new_line.loopback != 0 && new_line.loopback != 1)
250 		return -EINVAL;
251 
252 	memcpy(&port->settings, &new_line, size); /* Update settings */
253 	port->iface = new_type;
254 	pc300_set_iface(port);
255 	return 0;
256 }
257 
258 
259 
260 static void pc300_pci_remove_one(struct pci_dev *pdev)
261 {
262 	int i;
263 	card_t *card = pci_get_drvdata(pdev);
264 
265 	for (i = 0; i < 2; i++)
266 		if (card->ports[i].card)
267 			unregister_hdlc_device(card->ports[i].netdev);
268 
269 	if (card->irq)
270 		free_irq(card->irq, card);
271 
272 	if (card->rambase)
273 		iounmap(card->rambase);
274 	if (card->scabase)
275 		iounmap(card->scabase);
276 	if (card->plxbase)
277 		iounmap(card->plxbase);
278 
279 	pci_release_regions(pdev);
280 	pci_disable_device(pdev);
281 	if (card->ports[0].netdev)
282 		free_netdev(card->ports[0].netdev);
283 	if (card->ports[1].netdev)
284 		free_netdev(card->ports[1].netdev);
285 	kfree(card);
286 }
287 
288 static const struct net_device_ops pc300_ops = {
289 	.ndo_open       = pc300_open,
290 	.ndo_stop       = pc300_close,
291 	.ndo_start_xmit = hdlc_start_xmit,
292 	.ndo_do_ioctl   = pc300_ioctl,
293 };
294 
295 static int pc300_pci_init_one(struct pci_dev *pdev,
296 			      const struct pci_device_id *ent)
297 {
298 	card_t *card;
299 	u32 __iomem *p;
300 	int i;
301 	u32 ramsize;
302 	u32 ramphys;		/* buffer memory base */
303 	u32 scaphys;		/* SCA memory base */
304 	u32 plxphys;		/* PLX registers memory base */
305 
306 	i = pci_enable_device(pdev);
307 	if (i)
308 		return i;
309 
310 	i = pci_request_regions(pdev, "PC300");
311 	if (i) {
312 		pci_disable_device(pdev);
313 		return i;
314 	}
315 
316 	card = kzalloc(sizeof(card_t), GFP_KERNEL);
317 	if (card == NULL) {
318 		pci_release_regions(pdev);
319 		pci_disable_device(pdev);
320 		return -ENOBUFS;
321 	}
322 	pci_set_drvdata(pdev, card);
323 
324 	if (pci_resource_len(pdev, 0) != PC300_PLX_SIZE ||
325 	    pci_resource_len(pdev, 2) != PC300_SCA_SIZE ||
326 	    pci_resource_len(pdev, 3) < 16384) {
327 		pr_err("invalid card EEPROM parameters\n");
328 		pc300_pci_remove_one(pdev);
329 		return -EFAULT;
330 	}
331 
332 	plxphys = pci_resource_start(pdev, 0) & PCI_BASE_ADDRESS_MEM_MASK;
333 	card->plxbase = ioremap(plxphys, PC300_PLX_SIZE);
334 
335 	scaphys = pci_resource_start(pdev, 2) & PCI_BASE_ADDRESS_MEM_MASK;
336 	card->scabase = ioremap(scaphys, PC300_SCA_SIZE);
337 
338 	ramphys = pci_resource_start(pdev, 3) & PCI_BASE_ADDRESS_MEM_MASK;
339 	card->rambase = pci_ioremap_bar(pdev, 3);
340 
341 	if (card->plxbase == NULL ||
342 	    card->scabase == NULL ||
343 	    card->rambase == NULL) {
344 		pr_err("ioremap() failed\n");
345 		pc300_pci_remove_one(pdev);
346 		return -ENOMEM;
347 	}
348 
349 	/* PLX PCI 9050 workaround for local configuration register read bug */
350 	pci_write_config_dword(pdev, PCI_BASE_ADDRESS_0, scaphys);
351 	card->init_ctrl_value = readl(&((plx9050 __iomem *)card->scabase)->init_ctrl);
352 	pci_write_config_dword(pdev, PCI_BASE_ADDRESS_0, plxphys);
353 
354 	if (pdev->device == PCI_DEVICE_ID_PC300_TE_1 ||
355 	    pdev->device == PCI_DEVICE_ID_PC300_TE_2)
356 		card->type = PC300_TE; /* not fully supported */
357 	else if (card->init_ctrl_value & PC300_CTYPE_MASK)
358 		card->type = PC300_X21;
359 	else
360 		card->type = PC300_RSV;
361 
362 	if (pdev->device == PCI_DEVICE_ID_PC300_RX_1 ||
363 	    pdev->device == PCI_DEVICE_ID_PC300_TE_1)
364 		card->n_ports = 1;
365 	else
366 		card->n_ports = 2;
367 
368 	for (i = 0; i < card->n_ports; i++)
369 		if (!(card->ports[i].netdev = alloc_hdlcdev(&card->ports[i]))) {
370 			pr_err("unable to allocate memory\n");
371 			pc300_pci_remove_one(pdev);
372 			return -ENOMEM;
373 		}
374 
375 	/* Reset PLX */
376 	p = &card->plxbase->init_ctrl;
377 	writel(card->init_ctrl_value | 0x40000000, p);
378 	readl(p);		/* Flush the write - do not use sca_flush */
379 	udelay(1);
380 
381 	writel(card->init_ctrl_value, p);
382 	readl(p);		/* Flush the write - do not use sca_flush */
383 	udelay(1);
384 
385 	/* Reload Config. Registers from EEPROM */
386 	writel(card->init_ctrl_value | 0x20000000, p);
387 	readl(p);		/* Flush the write - do not use sca_flush */
388 	udelay(1);
389 
390 	writel(card->init_ctrl_value, p);
391 	readl(p);		/* Flush the write - do not use sca_flush */
392 	udelay(1);
393 
394 	ramsize = sca_detect_ram(card, card->rambase,
395 				 pci_resource_len(pdev, 3));
396 
397 	if (use_crystal_clock)
398 		card->init_ctrl_value &= ~PC300_CLKSEL_MASK;
399 	else
400 		card->init_ctrl_value |= PC300_CLKSEL_MASK;
401 
402 	writel(card->init_ctrl_value, &card->plxbase->init_ctrl);
403 	/* number of TX + RX buffers for one port */
404 	i = ramsize / (card->n_ports * (sizeof(pkt_desc) + HDLC_MAX_MRU));
405 	card->tx_ring_buffers = min(i / 2, MAX_TX_BUFFERS);
406 	card->rx_ring_buffers = i - card->tx_ring_buffers;
407 
408 	card->buff_offset = card->n_ports * sizeof(pkt_desc) *
409 		(card->tx_ring_buffers + card->rx_ring_buffers);
410 
411 	pr_info("PC300/%s, %u KB RAM at 0x%x, IRQ%u, using %u TX + %u RX packets rings\n",
412 		card->type == PC300_X21 ? "X21" :
413 		card->type == PC300_TE ? "TE" : "RSV",
414 		ramsize / 1024, ramphys, pdev->irq,
415 		card->tx_ring_buffers, card->rx_ring_buffers);
416 
417 	if (card->tx_ring_buffers < 1) {
418 		pr_err("RAM test failed\n");
419 		pc300_pci_remove_one(pdev);
420 		return -EFAULT;
421 	}
422 
423 	/* Enable interrupts on the PCI bridge, LINTi1 active low */
424 	writew(0x0041, &card->plxbase->intr_ctrl_stat);
425 
426 	/* Allocate IRQ */
427 	if (request_irq(pdev->irq, sca_intr, IRQF_SHARED, "pc300", card)) {
428 		pr_warn("could not allocate IRQ%d\n", pdev->irq);
429 		pc300_pci_remove_one(pdev);
430 		return -EBUSY;
431 	}
432 	card->irq = pdev->irq;
433 
434 	sca_init(card, 0);
435 
436 	// COTE not set - allows better TX DMA settings
437 	// sca_out(sca_in(PCR, card) | PCR_COTE, PCR, card);
438 
439 	sca_out(0x10, BTCR, card);
440 
441 	for (i = 0; i < card->n_ports; i++) {
442 		port_t *port = &card->ports[i];
443 		struct net_device *dev = port->netdev;
444 		hdlc_device *hdlc = dev_to_hdlc(dev);
445 		port->chan = i;
446 
447 		spin_lock_init(&port->lock);
448 		dev->irq = card->irq;
449 		dev->mem_start = ramphys;
450 		dev->mem_end = ramphys + ramsize - 1;
451 		dev->tx_queue_len = 50;
452 		dev->netdev_ops = &pc300_ops;
453 		hdlc->attach = sca_attach;
454 		hdlc->xmit = sca_xmit;
455 		port->settings.clock_type = CLOCK_EXT;
456 		port->card = card;
457 		if (card->type == PC300_X21)
458 			port->iface = IF_IFACE_X21;
459 		else
460 			port->iface = IF_IFACE_V35;
461 
462 		sca_init_port(port);
463 		if (register_hdlc_device(dev)) {
464 			pr_err("unable to register hdlc device\n");
465 			port->card = NULL;
466 			pc300_pci_remove_one(pdev);
467 			return -ENOBUFS;
468 		}
469 
470 		netdev_info(dev, "PC300 channel %d\n", port->chan);
471 	}
472 	return 0;
473 }
474 
475 
476 
477 static const struct pci_device_id pc300_pci_tbl[] = {
478 	{ PCI_VENDOR_ID_CYCLADES, PCI_DEVICE_ID_PC300_RX_1, PCI_ANY_ID,
479 	  PCI_ANY_ID, 0, 0, 0 },
480 	{ PCI_VENDOR_ID_CYCLADES, PCI_DEVICE_ID_PC300_RX_2, PCI_ANY_ID,
481 	  PCI_ANY_ID, 0, 0, 0 },
482 	{ PCI_VENDOR_ID_CYCLADES, PCI_DEVICE_ID_PC300_TE_1, PCI_ANY_ID,
483 	  PCI_ANY_ID, 0, 0, 0 },
484 	{ PCI_VENDOR_ID_CYCLADES, PCI_DEVICE_ID_PC300_TE_2, PCI_ANY_ID,
485 	  PCI_ANY_ID, 0, 0, 0 },
486 	{ 0, }
487 };
488 
489 
490 static struct pci_driver pc300_pci_driver = {
491 	.name =          "PC300",
492 	.id_table =      pc300_pci_tbl,
493 	.probe =         pc300_pci_init_one,
494 	.remove =        pc300_pci_remove_one,
495 };
496 
497 
498 static int __init pc300_init_module(void)
499 {
500 	if (pci_clock_freq < 1000000 || pci_clock_freq > 80000000) {
501 		pr_err("Invalid PCI clock frequency\n");
502 		return -EINVAL;
503 	}
504 	if (use_crystal_clock != 0 && use_crystal_clock != 1) {
505 		pr_err("Invalid 'use_crystal_clock' value\n");
506 		return -EINVAL;
507 	}
508 
509 	CLOCK_BASE = use_crystal_clock ? 24576000 : pci_clock_freq;
510 
511 	return pci_register_driver(&pc300_pci_driver);
512 }
513 
514 
515 
516 static void __exit pc300_cleanup_module(void)
517 {
518 	pci_unregister_driver(&pc300_pci_driver);
519 }
520 
521 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
522 MODULE_DESCRIPTION("Cyclades PC300 serial port driver");
523 MODULE_LICENSE("GPL v2");
524 MODULE_DEVICE_TABLE(pci, pc300_pci_tbl);
525 module_param(pci_clock_freq, int, 0444);
526 MODULE_PARM_DESC(pci_clock_freq, "System PCI clock frequency in Hz");
527 module_param(use_crystal_clock, int, 0444);
528 MODULE_PARM_DESC(use_crystal_clock,
529 		 "Use 24.576 MHz clock instead of PCI clock");
530 module_init(pc300_init_module);
531 module_exit(pc300_cleanup_module);
532