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
46static int pci_clock_freq = 33000000;
47static int use_crystal_clock = 0;
48static 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
56enum { 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 */
62typedef 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
76typedef 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
95typedef 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
117static 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
167static 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
182static int pc300_close(struct net_device *dev)
183{
184	sca_close(dev);
185	hdlc_close(dev);
186	return 0;
187}
188
189
190
191static 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
260static 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
288static 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
295static 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
477static 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
490static 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
498static 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
516static void __exit pc300_cleanup_module(void)
517{
518	pci_unregister_driver(&pc300_pci_driver);
519}
520
521MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
522MODULE_DESCRIPTION("Cyclades PC300 serial port driver");
523MODULE_LICENSE("GPL v2");
524MODULE_DEVICE_TABLE(pci, pc300_pci_tbl);
525module_param(pci_clock_freq, int, 0444);
526MODULE_PARM_DESC(pci_clock_freq, "System PCI clock frequency in Hz");
527module_param(use_crystal_clock, int, 0444);
528MODULE_PARM_DESC(use_crystal_clock,
529		 "Use 24.576 MHz clock instead of PCI clock");
530module_init(pc300_init_module);
531module_exit(pc300_cleanup_module);
532