xref: /openbmc/linux/drivers/net/wan/pci200syn.c (revision 0ad53fe3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Goramo PCI200SYN synchronous serial card driver for Linux
4  *
5  * Copyright (C) 2002-2008 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  *    PLX Technology Inc. PCI9052 Data Book
12  */
13 
14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15 
16 #include <linux/module.h>
17 #include <linux/kernel.h>
18 #include <linux/capability.h>
19 #include <linux/slab.h>
20 #include <linux/types.h>
21 #include <linux/fcntl.h>
22 #include <linux/in.h>
23 #include <linux/string.h>
24 #include <linux/errno.h>
25 #include <linux/init.h>
26 #include <linux/ioport.h>
27 #include <linux/netdevice.h>
28 #include <linux/hdlc.h>
29 #include <linux/pci.h>
30 #include <linux/delay.h>
31 #include <asm/io.h>
32 
33 #include "hd64572.h"
34 
35 #undef DEBUG_PKT
36 #define DEBUG_RINGS
37 
38 #define PCI200SYN_PLX_SIZE	0x80	/* PLX control window size (128b) */
39 #define PCI200SYN_SCA_SIZE	0x400	/* SCA window size (1Kb) */
40 #define MAX_TX_BUFFERS		10
41 
42 static int pci_clock_freq = 33000000;
43 #define CLOCK_BASE pci_clock_freq
44 
45 /*      PLX PCI9052 local configuration and shared runtime registers.
46  *      This structure can be used to access 9052 registers (memory mapped).
47  */
48 typedef struct {
49 	u32 loc_addr_range[4];	/* 00-0Ch : Local Address Ranges */
50 	u32 loc_rom_range;	/* 10h : Local ROM Range */
51 	u32 loc_addr_base[4];	/* 14-20h : Local Address Base Addrs */
52 	u32 loc_rom_base;	/* 24h : Local ROM Base */
53 	u32 loc_bus_descr[4];	/* 28-34h : Local Bus Descriptors */
54 	u32 rom_bus_descr;	/* 38h : ROM Bus Descriptor */
55 	u32 cs_base[4];		/* 3C-48h : Chip Select Base Addrs */
56 	u32 intr_ctrl_stat;	/* 4Ch : Interrupt Control/Status */
57 	u32 init_ctrl;		/* 50h : EEPROM ctrl, Init Ctrl, etc */
58 } plx9052;
59 
60 typedef struct port_s {
61 	struct napi_struct napi;
62 	struct net_device *netdev;
63 	struct card_s *card;
64 	spinlock_t lock;	/* TX lock */
65 	sync_serial_settings settings;
66 	int rxpart;		/* partial frame received, next frame invalid*/
67 	unsigned short encoding;
68 	unsigned short parity;
69 	u16 rxin;		/* rx ring buffer 'in' pointer */
70 	u16 txin;		/* tx ring buffer 'in' and 'last' pointers */
71 	u16 txlast;
72 	u8 rxs, txs, tmc;	/* SCA registers */
73 	u8 chan;		/* physical port # - 0 or 1 */
74 } port_t;
75 
76 typedef struct card_s {
77 	u8 __iomem *rambase;	/* buffer memory base (virtual) */
78 	u8 __iomem *scabase;	/* SCA memory base (virtual) */
79 	plx9052 __iomem *plxbase;/* PLX registers memory base (virtual) */
80 	u16 rx_ring_buffers;	/* number of buffers in a ring */
81 	u16 tx_ring_buffers;
82 	u16 buff_offset;	/* offset of first buffer of first channel */
83 	u8 irq;			/* interrupt request level */
84 
85 	port_t ports[2];
86 } card_t;
87 
88 #define get_port(card, port)	     (&(card)->ports[port])
89 #define sca_flush(card)		     (sca_in(IER0, card))
90 
91 static inline void new_memcpy_toio(char __iomem *dest, char *src, int length)
92 {
93 	int len;
94 
95 	do {
96 		len = length > 256 ? 256 : length;
97 		memcpy_toio(dest, src, len);
98 		dest += len;
99 		src += len;
100 		length -= len;
101 		readb(dest);
102 	} while (len);
103 }
104 
105 #undef memcpy_toio
106 #define memcpy_toio new_memcpy_toio
107 
108 #include "hd64572.c"
109 
110 static void pci200_set_iface(port_t *port)
111 {
112 	card_t *card = port->card;
113 	u16 msci = get_msci(port);
114 	u8 rxs = port->rxs & CLK_BRG_MASK;
115 	u8 txs = port->txs & CLK_BRG_MASK;
116 
117 	sca_out(EXS_TES1, (port->chan ? MSCI1_OFFSET : MSCI0_OFFSET) + EXS,
118 		port->card);
119 	switch (port->settings.clock_type) {
120 	case CLOCK_INT:
121 		rxs |= CLK_BRG; /* BRG output */
122 		txs |= CLK_PIN_OUT | CLK_TX_RXCLK; /* RX clock */
123 		break;
124 
125 	case CLOCK_TXINT:
126 		rxs |= CLK_LINE; /* RXC input */
127 		txs |= CLK_PIN_OUT | CLK_BRG; /* BRG output */
128 		break;
129 
130 	case CLOCK_TXFROMRX:
131 		rxs |= CLK_LINE; /* RXC input */
132 		txs |= CLK_PIN_OUT | CLK_TX_RXCLK; /* RX clock */
133 		break;
134 
135 	default:		/* EXTernal clock */
136 		rxs |= CLK_LINE; /* RXC input */
137 		txs |= CLK_PIN_OUT | CLK_LINE; /* TXC input */
138 		break;
139 	}
140 
141 	port->rxs = rxs;
142 	port->txs = txs;
143 	sca_out(rxs, msci + RXS, card);
144 	sca_out(txs, msci + TXS, card);
145 	sca_set_port(port);
146 }
147 
148 static int pci200_open(struct net_device *dev)
149 {
150 	port_t *port = dev_to_port(dev);
151 	int result = hdlc_open(dev);
152 
153 	if (result)
154 		return result;
155 
156 	sca_open(dev);
157 	pci200_set_iface(port);
158 	sca_flush(port->card);
159 	return 0;
160 }
161 
162 static int pci200_close(struct net_device *dev)
163 {
164 	sca_close(dev);
165 	sca_flush(dev_to_port(dev)->card);
166 	hdlc_close(dev);
167 	return 0;
168 }
169 
170 static int pci200_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
171 				 void __user *data, int cmd)
172 {
173 #ifdef DEBUG_RINGS
174 	if (cmd == SIOCDEVPRIVATE) {
175 		sca_dump_rings(dev);
176 		return 0;
177 	}
178 #endif
179 	return -EOPNOTSUPP;
180 }
181 
182 static int pci200_ioctl(struct net_device *dev, struct if_settings *ifs)
183 {
184 	const size_t size = sizeof(sync_serial_settings);
185 	sync_serial_settings new_line;
186 	sync_serial_settings __user *line = ifs->ifs_ifsu.sync;
187 	port_t *port = dev_to_port(dev);
188 
189 	switch (ifs->type) {
190 	case IF_GET_IFACE:
191 		ifs->type = IF_IFACE_V35;
192 		if (ifs->size < size) {
193 			ifs->size = size; /* data size wanted */
194 			return -ENOBUFS;
195 		}
196 		if (copy_to_user(line, &port->settings, size))
197 			return -EFAULT;
198 		return 0;
199 
200 	case IF_IFACE_V35:
201 	case IF_IFACE_SYNC_SERIAL:
202 		if (!capable(CAP_NET_ADMIN))
203 			return -EPERM;
204 
205 		if (copy_from_user(&new_line, line, size))
206 			return -EFAULT;
207 
208 		if (new_line.clock_type != CLOCK_EXT &&
209 		    new_line.clock_type != CLOCK_TXFROMRX &&
210 		    new_line.clock_type != CLOCK_INT &&
211 		    new_line.clock_type != CLOCK_TXINT)
212 			return -EINVAL;	/* No such clock setting */
213 
214 		if (new_line.loopback != 0 && new_line.loopback != 1)
215 			return -EINVAL;
216 
217 		memcpy(&port->settings, &new_line, size); /* Update settings */
218 		pci200_set_iface(port);
219 		sca_flush(port->card);
220 		return 0;
221 
222 	default:
223 		return hdlc_ioctl(dev, ifs);
224 	}
225 }
226 
227 static void pci200_pci_remove_one(struct pci_dev *pdev)
228 {
229 	int i;
230 	card_t *card = pci_get_drvdata(pdev);
231 
232 	for (i = 0; i < 2; i++)
233 		if (card->ports[i].card)
234 			unregister_hdlc_device(card->ports[i].netdev);
235 
236 	if (card->irq)
237 		free_irq(card->irq, card);
238 
239 	if (card->rambase)
240 		iounmap(card->rambase);
241 	if (card->scabase)
242 		iounmap(card->scabase);
243 	if (card->plxbase)
244 		iounmap(card->plxbase);
245 
246 	pci_release_regions(pdev);
247 	pci_disable_device(pdev);
248 	if (card->ports[0].netdev)
249 		free_netdev(card->ports[0].netdev);
250 	if (card->ports[1].netdev)
251 		free_netdev(card->ports[1].netdev);
252 	kfree(card);
253 }
254 
255 static const struct net_device_ops pci200_ops = {
256 	.ndo_open       = pci200_open,
257 	.ndo_stop       = pci200_close,
258 	.ndo_start_xmit = hdlc_start_xmit,
259 	.ndo_siocwandev = pci200_ioctl,
260 	.ndo_siocdevprivate = pci200_siocdevprivate,
261 };
262 
263 static int pci200_pci_init_one(struct pci_dev *pdev,
264 			       const struct pci_device_id *ent)
265 {
266 	card_t *card;
267 	u32 __iomem *p;
268 	int i;
269 	u32 ramsize;
270 	u32 ramphys;		/* buffer memory base */
271 	u32 scaphys;		/* SCA memory base */
272 	u32 plxphys;		/* PLX registers memory base */
273 
274 	i = pci_enable_device(pdev);
275 	if (i)
276 		return i;
277 
278 	i = pci_request_regions(pdev, "PCI200SYN");
279 	if (i) {
280 		pci_disable_device(pdev);
281 		return i;
282 	}
283 
284 	card = kzalloc(sizeof(card_t), GFP_KERNEL);
285 	if (!card) {
286 		pci_release_regions(pdev);
287 		pci_disable_device(pdev);
288 		return -ENOBUFS;
289 	}
290 	pci_set_drvdata(pdev, card);
291 	card->ports[0].netdev = alloc_hdlcdev(&card->ports[0]);
292 	card->ports[1].netdev = alloc_hdlcdev(&card->ports[1]);
293 	if (!card->ports[0].netdev || !card->ports[1].netdev) {
294 		pr_err("unable to allocate memory\n");
295 		pci200_pci_remove_one(pdev);
296 		return -ENOMEM;
297 	}
298 
299 	if (pci_resource_len(pdev, 0) != PCI200SYN_PLX_SIZE ||
300 	    pci_resource_len(pdev, 2) != PCI200SYN_SCA_SIZE ||
301 	    pci_resource_len(pdev, 3) < 16384) {
302 		pr_err("invalid card EEPROM parameters\n");
303 		pci200_pci_remove_one(pdev);
304 		return -EFAULT;
305 	}
306 
307 	plxphys = pci_resource_start(pdev, 0) & PCI_BASE_ADDRESS_MEM_MASK;
308 	card->plxbase = ioremap(plxphys, PCI200SYN_PLX_SIZE);
309 
310 	scaphys = pci_resource_start(pdev, 2) & PCI_BASE_ADDRESS_MEM_MASK;
311 	card->scabase = ioremap(scaphys, PCI200SYN_SCA_SIZE);
312 
313 	ramphys = pci_resource_start(pdev, 3) & PCI_BASE_ADDRESS_MEM_MASK;
314 	card->rambase = pci_ioremap_bar(pdev, 3);
315 
316 	if (!card->plxbase || !card->scabase || !card->rambase) {
317 		pr_err("ioremap() failed\n");
318 		pci200_pci_remove_one(pdev);
319 		return -EFAULT;
320 	}
321 
322 	/* Reset PLX */
323 	p = &card->plxbase->init_ctrl;
324 	writel(readl(p) | 0x40000000, p);
325 	readl(p);		/* Flush the write - do not use sca_flush */
326 	udelay(1);
327 
328 	writel(readl(p) & ~0x40000000, p);
329 	readl(p);		/* Flush the write - do not use sca_flush */
330 	udelay(1);
331 
332 	ramsize = sca_detect_ram(card, card->rambase,
333 				 pci_resource_len(pdev, 3));
334 
335 	/* number of TX + RX buffers for one port - this is dual port card */
336 	i = ramsize / (2 * (sizeof(pkt_desc) + HDLC_MAX_MRU));
337 	card->tx_ring_buffers = min(i / 2, MAX_TX_BUFFERS);
338 	card->rx_ring_buffers = i - card->tx_ring_buffers;
339 
340 	card->buff_offset = 2 * sizeof(pkt_desc) * (card->tx_ring_buffers +
341 						    card->rx_ring_buffers);
342 
343 	pr_info("%u KB RAM at 0x%x, IRQ%u, using %u TX + %u RX packets rings\n",
344 		ramsize / 1024, ramphys,
345 		pdev->irq, card->tx_ring_buffers, card->rx_ring_buffers);
346 
347 	if (card->tx_ring_buffers < 1) {
348 		pr_err("RAM test failed\n");
349 		pci200_pci_remove_one(pdev);
350 		return -EFAULT;
351 	}
352 
353 	/* Enable interrupts on the PCI bridge */
354 	p = &card->plxbase->intr_ctrl_stat;
355 	writew(readw(p) | 0x0040, p);
356 
357 	/* Allocate IRQ */
358 	if (request_irq(pdev->irq, sca_intr, IRQF_SHARED, "pci200syn", card)) {
359 		pr_warn("could not allocate IRQ%d\n", pdev->irq);
360 		pci200_pci_remove_one(pdev);
361 		return -EBUSY;
362 	}
363 	card->irq = pdev->irq;
364 
365 	sca_init(card, 0);
366 
367 	for (i = 0; i < 2; i++) {
368 		port_t *port = &card->ports[i];
369 		struct net_device *dev = port->netdev;
370 		hdlc_device *hdlc = dev_to_hdlc(dev);
371 
372 		port->chan = i;
373 
374 		spin_lock_init(&port->lock);
375 		dev->irq = card->irq;
376 		dev->mem_start = ramphys;
377 		dev->mem_end = ramphys + ramsize - 1;
378 		dev->tx_queue_len = 50;
379 		dev->netdev_ops = &pci200_ops;
380 		hdlc->attach = sca_attach;
381 		hdlc->xmit = sca_xmit;
382 		port->settings.clock_type = CLOCK_EXT;
383 		port->card = card;
384 		sca_init_port(port);
385 		if (register_hdlc_device(dev)) {
386 			pr_err("unable to register hdlc device\n");
387 			port->card = NULL;
388 			pci200_pci_remove_one(pdev);
389 			return -ENOBUFS;
390 		}
391 
392 		netdev_info(dev, "PCI200SYN channel %d\n", port->chan);
393 	}
394 
395 	sca_flush(card);
396 	return 0;
397 }
398 
399 static const struct pci_device_id pci200_pci_tbl[] = {
400 	{ PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9050, PCI_VENDOR_ID_PLX,
401 	  PCI_DEVICE_ID_PLX_PCI200SYN, 0, 0, 0 },
402 	{ 0, }
403 };
404 
405 static struct pci_driver pci200_pci_driver = {
406 	.name		= "PCI200SYN",
407 	.id_table	= pci200_pci_tbl,
408 	.probe		= pci200_pci_init_one,
409 	.remove		= pci200_pci_remove_one,
410 };
411 
412 static int __init pci200_init_module(void)
413 {
414 	if (pci_clock_freq < 1000000 || pci_clock_freq > 80000000) {
415 		pr_err("Invalid PCI clock frequency\n");
416 		return -EINVAL;
417 	}
418 	return pci_register_driver(&pci200_pci_driver);
419 }
420 
421 static void __exit pci200_cleanup_module(void)
422 {
423 	pci_unregister_driver(&pci200_pci_driver);
424 }
425 
426 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
427 MODULE_DESCRIPTION("Goramo PCI200SYN serial port driver");
428 MODULE_LICENSE("GPL v2");
429 MODULE_DEVICE_TABLE(pci, pci200_pci_tbl);
430 module_param(pci_clock_freq, int, 0444);
431 MODULE_PARM_DESC(pci_clock_freq, "System PCI clock frequency in Hz");
432 module_init(pci200_init_module);
433 module_exit(pci200_cleanup_module);
434