xref: /linux/drivers/rapidio/rio-scan.c (revision 14b42963f64b98ab61fa9723c03d71aa5ef4f862)
1 /*
2  * RapidIO enumeration and discovery support
3  *
4  * Copyright 2005 MontaVista Software, Inc.
5  * Matt Porter <mporter@kernel.crashing.org>
6  *
7  * This program is free software; you can redistribute  it and/or modify it
8  * under  the terms of  the GNU General  Public License as published by the
9  * Free Software Foundation;  either version 2 of the  License, or (at your
10  * option) any later version.
11  */
12 
13 #include <linux/types.h>
14 #include <linux/kernel.h>
15 
16 #include <linux/delay.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/init.h>
19 #include <linux/rio.h>
20 #include <linux/rio_drv.h>
21 #include <linux/rio_ids.h>
22 #include <linux/rio_regs.h>
23 #include <linux/module.h>
24 #include <linux/spinlock.h>
25 #include <linux/timer.h>
26 #include <linux/jiffies.h>
27 #include <linux/slab.h>
28 
29 #include "rio.h"
30 
31 LIST_HEAD(rio_devices);
32 static LIST_HEAD(rio_switches);
33 
34 #define RIO_ENUM_CMPL_MAGIC	0xdeadbeef
35 
36 static void rio_enum_timeout(unsigned long);
37 
38 DEFINE_SPINLOCK(rio_global_list_lock);
39 
40 static int next_destid = 0;
41 static int next_switchid = 0;
42 static int next_net = 0;
43 
44 static struct timer_list rio_enum_timer =
45 TIMER_INITIALIZER(rio_enum_timeout, 0, 0);
46 
47 static int rio_mport_phys_table[] = {
48 	RIO_EFB_PAR_EP_ID,
49 	RIO_EFB_PAR_EP_REC_ID,
50 	RIO_EFB_SER_EP_ID,
51 	RIO_EFB_SER_EP_REC_ID,
52 	-1,
53 };
54 
55 static int rio_sport_phys_table[] = {
56 	RIO_EFB_PAR_EP_FREE_ID,
57 	RIO_EFB_SER_EP_FREE_ID,
58 	-1,
59 };
60 
61 /**
62  * rio_get_device_id - Get the base/extended device id for a device
63  * @port: RIO master port
64  * @destid: Destination ID of device
65  * @hopcount: Hopcount to device
66  *
67  * Reads the base/extended device id from a device. Returns the
68  * 8/16-bit device ID.
69  */
70 static u16 rio_get_device_id(struct rio_mport *port, u16 destid, u8 hopcount)
71 {
72 	u32 result;
73 
74 	rio_mport_read_config_32(port, destid, hopcount, RIO_DID_CSR, &result);
75 
76 	return RIO_GET_DID(result);
77 }
78 
79 /**
80  * rio_set_device_id - Set the base/extended device id for a device
81  * @port: RIO master port
82  * @destid: Destination ID of device
83  * @hopcount: Hopcount to device
84  * @did: Device ID value to be written
85  *
86  * Writes the base/extended device id from a device.
87  */
88 static void rio_set_device_id(struct rio_mport *port, u16 destid, u8 hopcount, u16 did)
89 {
90 	rio_mport_write_config_32(port, destid, hopcount, RIO_DID_CSR,
91 				  RIO_SET_DID(did));
92 }
93 
94 /**
95  * rio_local_set_device_id - Set the base/extended device id for a port
96  * @port: RIO master port
97  * @did: Device ID value to be written
98  *
99  * Writes the base/extended device id from a device.
100  */
101 static void rio_local_set_device_id(struct rio_mport *port, u16 did)
102 {
103 	rio_local_write_config_32(port, RIO_DID_CSR, RIO_SET_DID(did));
104 }
105 
106 /**
107  * rio_clear_locks- Release all host locks and signal enumeration complete
108  * @port: Master port to issue transaction
109  *
110  * Marks the component tag CSR on each device with the enumeration
111  * complete flag. When complete, it then release the host locks on
112  * each device. Returns 0 on success or %-EINVAL on failure.
113  */
114 static int rio_clear_locks(struct rio_mport *port)
115 {
116 	struct rio_dev *rdev;
117 	u32 result;
118 	int ret = 0;
119 
120 	/* Write component tag CSR magic complete value */
121 	rio_local_write_config_32(port, RIO_COMPONENT_TAG_CSR,
122 				  RIO_ENUM_CMPL_MAGIC);
123 	list_for_each_entry(rdev, &rio_devices, global_list)
124 	    rio_write_config_32(rdev, RIO_COMPONENT_TAG_CSR,
125 				RIO_ENUM_CMPL_MAGIC);
126 
127 	/* Release host device id locks */
128 	rio_local_write_config_32(port, RIO_HOST_DID_LOCK_CSR,
129 				  port->host_deviceid);
130 	rio_local_read_config_32(port, RIO_HOST_DID_LOCK_CSR, &result);
131 	if ((result & 0xffff) != 0xffff) {
132 		printk(KERN_INFO
133 		       "RIO: badness when releasing host lock on master port, result %8.8x\n",
134 		       result);
135 		ret = -EINVAL;
136 	}
137 	list_for_each_entry(rdev, &rio_devices, global_list) {
138 		rio_write_config_32(rdev, RIO_HOST_DID_LOCK_CSR,
139 				    port->host_deviceid);
140 		rio_read_config_32(rdev, RIO_HOST_DID_LOCK_CSR, &result);
141 		if ((result & 0xffff) != 0xffff) {
142 			printk(KERN_INFO
143 			       "RIO: badness when releasing host lock on vid %4.4x did %4.4x\n",
144 			       rdev->vid, rdev->did);
145 			ret = -EINVAL;
146 		}
147 	}
148 
149 	return ret;
150 }
151 
152 /**
153  * rio_enum_host- Set host lock and initialize host destination ID
154  * @port: Master port to issue transaction
155  *
156  * Sets the local host master port lock and destination ID register
157  * with the host device ID value. The host device ID value is provided
158  * by the platform. Returns %0 on success or %-1 on failure.
159  */
160 static int rio_enum_host(struct rio_mport *port)
161 {
162 	u32 result;
163 
164 	/* Set master port host device id lock */
165 	rio_local_write_config_32(port, RIO_HOST_DID_LOCK_CSR,
166 				  port->host_deviceid);
167 
168 	rio_local_read_config_32(port, RIO_HOST_DID_LOCK_CSR, &result);
169 	if ((result & 0xffff) != port->host_deviceid)
170 		return -1;
171 
172 	/* Set master port destid and init destid ctr */
173 	rio_local_set_device_id(port, port->host_deviceid);
174 
175 	if (next_destid == port->host_deviceid)
176 		next_destid++;
177 
178 	return 0;
179 }
180 
181 /**
182  * rio_device_has_destid- Test if a device contains a destination ID register
183  * @port: Master port to issue transaction
184  * @src_ops: RIO device source operations
185  * @dst_ops: RIO device destination operations
186  *
187  * Checks the provided @src_ops and @dst_ops for the necessary transaction
188  * capabilities that indicate whether or not a device will implement a
189  * destination ID register. Returns 1 if true or 0 if false.
190  */
191 static int rio_device_has_destid(struct rio_mport *port, int src_ops,
192 				 int dst_ops)
193 {
194 	u32 mask = RIO_OPS_READ | RIO_OPS_WRITE | RIO_OPS_ATOMIC_TST_SWP | RIO_OPS_ATOMIC_INC | RIO_OPS_ATOMIC_DEC | RIO_OPS_ATOMIC_SET | RIO_OPS_ATOMIC_CLR;
195 
196 	return !!((src_ops | dst_ops) & mask);
197 }
198 
199 /**
200  * rio_release_dev- Frees a RIO device struct
201  * @dev: LDM device associated with a RIO device struct
202  *
203  * Gets the RIO device struct associated a RIO device struct.
204  * The RIO device struct is freed.
205  */
206 static void rio_release_dev(struct device *dev)
207 {
208 	struct rio_dev *rdev;
209 
210 	rdev = to_rio_dev(dev);
211 	kfree(rdev);
212 }
213 
214 /**
215  * rio_is_switch- Tests if a RIO device has switch capabilities
216  * @rdev: RIO device
217  *
218  * Gets the RIO device Processing Element Features register
219  * contents and tests for switch capabilities. Returns 1 if
220  * the device is a switch or 0 if it is not a switch.
221  * The RIO device struct is freed.
222  */
223 static int rio_is_switch(struct rio_dev *rdev)
224 {
225 	if (rdev->pef & RIO_PEF_SWITCH)
226 		return 1;
227 	return 0;
228 }
229 
230 /**
231  * rio_route_set_ops- Sets routing operations for a particular vendor switch
232  * @rdev: RIO device
233  *
234  * Searches the RIO route ops table for known switch types. If the vid
235  * and did match a switch table entry, then set the add_entry() and
236  * get_entry() ops to the table entry values.
237  */
238 static void rio_route_set_ops(struct rio_dev *rdev)
239 {
240 	struct rio_route_ops *cur = __start_rio_route_ops;
241 	struct rio_route_ops *end = __end_rio_route_ops;
242 
243 	while (cur < end) {
244 		if ((cur->vid == rdev->vid) && (cur->did == rdev->did)) {
245 			pr_debug("RIO: adding routing ops for %s\n", rio_name(rdev));
246 			rdev->rswitch->add_entry = cur->add_hook;
247 			rdev->rswitch->get_entry = cur->get_hook;
248 		}
249 		cur++;
250 	}
251 
252 	if (!rdev->rswitch->add_entry || !rdev->rswitch->get_entry)
253 		printk(KERN_ERR "RIO: missing routing ops for %s\n",
254 		       rio_name(rdev));
255 }
256 
257 /**
258  * rio_add_device- Adds a RIO device to the device model
259  * @rdev: RIO device
260  *
261  * Adds the RIO device to the global device list and adds the RIO
262  * device to the RIO device list.  Creates the generic sysfs nodes
263  * for an RIO device.
264  */
265 static void __devinit rio_add_device(struct rio_dev *rdev)
266 {
267 	device_add(&rdev->dev);
268 
269 	spin_lock(&rio_global_list_lock);
270 	list_add_tail(&rdev->global_list, &rio_devices);
271 	spin_unlock(&rio_global_list_lock);
272 
273 	rio_create_sysfs_dev_files(rdev);
274 }
275 
276 /**
277  * rio_setup_device- Allocates and sets up a RIO device
278  * @net: RIO network
279  * @port: Master port to send transactions
280  * @destid: Current destination ID
281  * @hopcount: Current hopcount
282  * @do_enum: Enumeration/Discovery mode flag
283  *
284  * Allocates a RIO device and configures fields based on configuration
285  * space contents. If device has a destination ID register, a destination
286  * ID is either assigned in enumeration mode or read from configuration
287  * space in discovery mode.  If the device has switch capabilities, then
288  * a switch is allocated and configured appropriately. Returns a pointer
289  * to a RIO device on success or NULL on failure.
290  *
291  */
292 static struct rio_dev *rio_setup_device(struct rio_net *net,
293 					struct rio_mport *port, u16 destid,
294 					u8 hopcount, int do_enum)
295 {
296 	struct rio_dev *rdev;
297 	struct rio_switch *rswitch;
298 	int result, rdid;
299 
300 	rdev = kmalloc(sizeof(struct rio_dev), GFP_KERNEL);
301 	if (!rdev)
302 		goto out;
303 
304 	memset(rdev, 0, sizeof(struct rio_dev));
305 	rdev->net = net;
306 	rio_mport_read_config_32(port, destid, hopcount, RIO_DEV_ID_CAR,
307 				 &result);
308 	rdev->did = result >> 16;
309 	rdev->vid = result & 0xffff;
310 	rio_mport_read_config_32(port, destid, hopcount, RIO_DEV_INFO_CAR,
311 				 &rdev->device_rev);
312 	rio_mport_read_config_32(port, destid, hopcount, RIO_ASM_ID_CAR,
313 				 &result);
314 	rdev->asm_did = result >> 16;
315 	rdev->asm_vid = result & 0xffff;
316 	rio_mport_read_config_32(port, destid, hopcount, RIO_ASM_INFO_CAR,
317 				 &result);
318 	rdev->asm_rev = result >> 16;
319 	rio_mport_read_config_32(port, destid, hopcount, RIO_PEF_CAR,
320 				 &rdev->pef);
321 	if (rdev->pef & RIO_PEF_EXT_FEATURES)
322 		rdev->efptr = result & 0xffff;
323 
324 	rio_mport_read_config_32(port, destid, hopcount, RIO_SRC_OPS_CAR,
325 				 &rdev->src_ops);
326 	rio_mport_read_config_32(port, destid, hopcount, RIO_DST_OPS_CAR,
327 				 &rdev->dst_ops);
328 
329 	if (rio_device_has_destid(port, rdev->src_ops, rdev->dst_ops)
330 	    && do_enum) {
331 		rio_set_device_id(port, destid, hopcount, next_destid);
332 		rdev->destid = next_destid++;
333 		if (next_destid == port->host_deviceid)
334 			next_destid++;
335 	} else
336 		rdev->destid = rio_get_device_id(port, destid, hopcount);
337 
338 	/* If a PE has both switch and other functions, show it as a switch */
339 	if (rio_is_switch(rdev)) {
340 		rio_mport_read_config_32(port, destid, hopcount,
341 					 RIO_SWP_INFO_CAR, &rdev->swpinfo);
342 		rswitch = kmalloc(sizeof(struct rio_switch), GFP_KERNEL);
343 		if (!rswitch) {
344 			kfree(rdev);
345 			rdev = NULL;
346 			goto out;
347 		}
348 		rswitch->switchid = next_switchid;
349 		rswitch->hopcount = hopcount;
350 		rswitch->destid = 0xffff;
351 		/* Initialize switch route table */
352 		for (rdid = 0; rdid < RIO_MAX_ROUTE_ENTRIES; rdid++)
353 			rswitch->route_table[rdid] = RIO_INVALID_ROUTE;
354 		rdev->rswitch = rswitch;
355 		sprintf(rio_name(rdev), "%02x:s:%04x", rdev->net->id,
356 			rdev->rswitch->switchid);
357 		rio_route_set_ops(rdev);
358 
359 		list_add_tail(&rswitch->node, &rio_switches);
360 
361 	} else
362 		sprintf(rio_name(rdev), "%02x:e:%04x", rdev->net->id,
363 			rdev->destid);
364 
365 	rdev->dev.bus = &rio_bus_type;
366 
367 	device_initialize(&rdev->dev);
368 	rdev->dev.release = rio_release_dev;
369 	rio_dev_get(rdev);
370 
371 	rdev->dma_mask = DMA_32BIT_MASK;
372 	rdev->dev.dma_mask = &rdev->dma_mask;
373 	rdev->dev.coherent_dma_mask = DMA_32BIT_MASK;
374 
375 	if ((rdev->pef & RIO_PEF_INB_DOORBELL) &&
376 	    (rdev->dst_ops & RIO_DST_OPS_DOORBELL))
377 		rio_init_dbell_res(&rdev->riores[RIO_DOORBELL_RESOURCE],
378 				   0, 0xffff);
379 
380 	rio_add_device(rdev);
381 
382       out:
383 	return rdev;
384 }
385 
386 /**
387  * rio_sport_is_active- Tests if a switch port has an active connection.
388  * @port: Master port to send transaction
389  * @destid: Associated destination ID for switch
390  * @hopcount: Hopcount to reach switch
391  * @sport: Switch port number
392  *
393  * Reads the port error status CSR for a particular switch port to
394  * determine if the port has an active link.  Returns
395  * %PORT_N_ERR_STS_PORT_OK if the port is active or %0 if it is
396  * inactive.
397  */
398 static int
399 rio_sport_is_active(struct rio_mport *port, u16 destid, u8 hopcount, int sport)
400 {
401 	u32 result;
402 	u32 ext_ftr_ptr;
403 
404 	int *entry = rio_sport_phys_table;
405 
406 	do {
407 		if ((ext_ftr_ptr =
408 		     rio_mport_get_feature(port, 0, destid, hopcount, *entry)))
409 
410 			break;
411 	} while (*++entry >= 0);
412 
413 	if (ext_ftr_ptr)
414 		rio_mport_read_config_32(port, destid, hopcount,
415 					 ext_ftr_ptr +
416 					 RIO_PORT_N_ERR_STS_CSR(sport),
417 					 &result);
418 
419 	return (result & PORT_N_ERR_STS_PORT_OK);
420 }
421 
422 /**
423  * rio_route_add_entry- Add a route entry to a switch routing table
424  * @mport: Master port to send transaction
425  * @rdev: Switch device
426  * @table: Routing table ID
427  * @route_destid: Destination ID to be routed
428  * @route_port: Port number to be routed
429  *
430  * Calls the switch specific add_entry() method to add a route entry
431  * on a switch. The route table can be specified using the @table
432  * argument if a switch has per port routing tables or the normal
433  * use is to specific all tables (or the global table) by passing
434  * %RIO_GLOBAL_TABLE in @table. Returns %0 on success or %-EINVAL
435  * on failure.
436  */
437 static int rio_route_add_entry(struct rio_mport *mport, struct rio_dev *rdev,
438 			       u16 table, u16 route_destid, u8 route_port)
439 {
440 	return rdev->rswitch->add_entry(mport, rdev->rswitch->destid,
441 					rdev->rswitch->hopcount, table,
442 					route_destid, route_port);
443 }
444 
445 /**
446  * rio_route_get_entry- Read a route entry in a switch routing table
447  * @mport: Master port to send transaction
448  * @rdev: Switch device
449  * @table: Routing table ID
450  * @route_destid: Destination ID to be routed
451  * @route_port: Pointer to read port number into
452  *
453  * Calls the switch specific get_entry() method to read a route entry
454  * in a switch. The route table can be specified using the @table
455  * argument if a switch has per port routing tables or the normal
456  * use is to specific all tables (or the global table) by passing
457  * %RIO_GLOBAL_TABLE in @table. Returns %0 on success or %-EINVAL
458  * on failure.
459  */
460 static int
461 rio_route_get_entry(struct rio_mport *mport, struct rio_dev *rdev, u16 table,
462 		    u16 route_destid, u8 * route_port)
463 {
464 	return rdev->rswitch->get_entry(mport, rdev->rswitch->destid,
465 					rdev->rswitch->hopcount, table,
466 					route_destid, route_port);
467 }
468 
469 /**
470  * rio_get_host_deviceid_lock- Reads the Host Device ID Lock CSR on a device
471  * @port: Master port to send transaction
472  * @hopcount: Number of hops to the device
473  *
474  * Used during enumeration to read the Host Device ID Lock CSR on a
475  * RIO device. Returns the value of the lock register.
476  */
477 static u16 rio_get_host_deviceid_lock(struct rio_mport *port, u8 hopcount)
478 {
479 	u32 result;
480 
481 	rio_mport_read_config_32(port, RIO_ANY_DESTID, hopcount,
482 				 RIO_HOST_DID_LOCK_CSR, &result);
483 
484 	return (u16) (result & 0xffff);
485 }
486 
487 /**
488  * rio_get_swpinfo_inport- Gets the ingress port number
489  * @mport: Master port to send transaction
490  * @destid: Destination ID associated with the switch
491  * @hopcount: Number of hops to the device
492  *
493  * Returns port number being used to access the switch device.
494  */
495 static u8
496 rio_get_swpinfo_inport(struct rio_mport *mport, u16 destid, u8 hopcount)
497 {
498 	u32 result;
499 
500 	rio_mport_read_config_32(mport, destid, hopcount, RIO_SWP_INFO_CAR,
501 				 &result);
502 
503 	return (u8) (result & 0xff);
504 }
505 
506 /**
507  * rio_get_swpinfo_tports- Gets total number of ports on the switch
508  * @mport: Master port to send transaction
509  * @destid: Destination ID associated with the switch
510  * @hopcount: Number of hops to the device
511  *
512  * Returns total numbers of ports implemented by the switch device.
513  */
514 static u8 rio_get_swpinfo_tports(struct rio_mport *mport, u16 destid,
515 				 u8 hopcount)
516 {
517 	u32 result;
518 
519 	rio_mport_read_config_32(mport, destid, hopcount, RIO_SWP_INFO_CAR,
520 				 &result);
521 
522 	return RIO_GET_TOTAL_PORTS(result);
523 }
524 
525 /**
526  * rio_net_add_mport- Add a master port to a RIO network
527  * @net: RIO network
528  * @port: Master port to add
529  *
530  * Adds a master port to the network list of associated master
531  * ports..
532  */
533 static void rio_net_add_mport(struct rio_net *net, struct rio_mport *port)
534 {
535 	spin_lock(&rio_global_list_lock);
536 	list_add_tail(&port->nnode, &net->mports);
537 	spin_unlock(&rio_global_list_lock);
538 }
539 
540 /**
541  * rio_enum_peer- Recursively enumerate a RIO network through a master port
542  * @net: RIO network being enumerated
543  * @port: Master port to send transactions
544  * @hopcount: Number of hops into the network
545  *
546  * Recursively enumerates a RIO network.  Transactions are sent via the
547  * master port passed in @port.
548  */
549 static int rio_enum_peer(struct rio_net *net, struct rio_mport *port,
550 			 u8 hopcount)
551 {
552 	int port_num;
553 	int num_ports;
554 	int cur_destid;
555 	struct rio_dev *rdev;
556 	u16 destid;
557 	int tmp;
558 
559 	if (rio_get_host_deviceid_lock(port, hopcount) == port->host_deviceid) {
560 		pr_debug("RIO: PE already discovered by this host\n");
561 		/*
562 		 * Already discovered by this host. Add it as another
563 		 * master port for the current network.
564 		 */
565 		rio_net_add_mport(net, port);
566 		return 0;
567 	}
568 
569 	/* Attempt to acquire device lock */
570 	rio_mport_write_config_32(port, RIO_ANY_DESTID, hopcount,
571 				  RIO_HOST_DID_LOCK_CSR, port->host_deviceid);
572 	while ((tmp = rio_get_host_deviceid_lock(port, hopcount))
573 	       < port->host_deviceid) {
574 		/* Delay a bit */
575 		mdelay(1);
576 		/* Attempt to acquire device lock again */
577 		rio_mport_write_config_32(port, RIO_ANY_DESTID, hopcount,
578 					  RIO_HOST_DID_LOCK_CSR,
579 					  port->host_deviceid);
580 	}
581 
582 	if (rio_get_host_deviceid_lock(port, hopcount) > port->host_deviceid) {
583 		pr_debug(
584 		    "RIO: PE locked by a higher priority host...retreating\n");
585 		return -1;
586 	}
587 
588 	/* Setup new RIO device */
589 	if ((rdev = rio_setup_device(net, port, RIO_ANY_DESTID, hopcount, 1))) {
590 		/* Add device to the global and bus/net specific list. */
591 		list_add_tail(&rdev->net_list, &net->devices);
592 	} else
593 		return -1;
594 
595 	if (rio_is_switch(rdev)) {
596 		next_switchid++;
597 
598 		for (destid = 0; destid < next_destid; destid++) {
599 			rio_route_add_entry(port, rdev, RIO_GLOBAL_TABLE,
600 					    destid, rio_get_swpinfo_inport(port,
601 									   RIO_ANY_DESTID,
602 									   hopcount));
603 			rdev->rswitch->route_table[destid] =
604 			    rio_get_swpinfo_inport(port, RIO_ANY_DESTID,
605 						   hopcount);
606 		}
607 
608 		num_ports =
609 		    rio_get_swpinfo_tports(port, RIO_ANY_DESTID, hopcount);
610 		pr_debug(
611 		    "RIO: found %s (vid %4.4x did %4.4x) with %d ports\n",
612 		    rio_name(rdev), rdev->vid, rdev->did, num_ports);
613 		for (port_num = 0; port_num < num_ports; port_num++) {
614 			if (rio_get_swpinfo_inport
615 			    (port, RIO_ANY_DESTID, hopcount) == port_num)
616 				continue;
617 
618 			cur_destid = next_destid;
619 
620 			if (rio_sport_is_active
621 			    (port, RIO_ANY_DESTID, hopcount, port_num)) {
622 				pr_debug(
623 				    "RIO: scanning device on port %d\n",
624 				    port_num);
625 				rio_route_add_entry(port, rdev,
626 						    RIO_GLOBAL_TABLE,
627 						    RIO_ANY_DESTID, port_num);
628 
629 				if (rio_enum_peer(net, port, hopcount + 1) < 0)
630 					return -1;
631 
632 				/* Update routing tables */
633 				if (next_destid > cur_destid) {
634 					for (destid = cur_destid;
635 					     destid < next_destid; destid++) {
636 						rio_route_add_entry(port, rdev,
637 								    RIO_GLOBAL_TABLE,
638 								    destid,
639 								    port_num);
640 						rdev->rswitch->
641 						    route_table[destid] =
642 						    port_num;
643 					}
644 					rdev->rswitch->destid = cur_destid;
645 				}
646 			}
647 		}
648 	} else
649 		pr_debug("RIO: found %s (vid %4.4x did %4.4x)\n",
650 		    rio_name(rdev), rdev->vid, rdev->did);
651 
652 	return 0;
653 }
654 
655 /**
656  * rio_enum_complete- Tests if enumeration of a network is complete
657  * @port: Master port to send transaction
658  *
659  * Tests the Component Tag CSR for presence of the magic enumeration
660  * complete flag. Return %1 if enumeration is complete or %0 if
661  * enumeration is incomplete.
662  */
663 static int rio_enum_complete(struct rio_mport *port)
664 {
665 	u32 tag_csr;
666 	int ret = 0;
667 
668 	rio_local_read_config_32(port, RIO_COMPONENT_TAG_CSR, &tag_csr);
669 
670 	if (tag_csr == RIO_ENUM_CMPL_MAGIC)
671 		ret = 1;
672 
673 	return ret;
674 }
675 
676 /**
677  * rio_disc_peer- Recursively discovers a RIO network through a master port
678  * @net: RIO network being discovered
679  * @port: Master port to send transactions
680  * @destid: Current destination ID in network
681  * @hopcount: Number of hops into the network
682  *
683  * Recursively discovers a RIO network.  Transactions are sent via the
684  * master port passed in @port.
685  */
686 static int
687 rio_disc_peer(struct rio_net *net, struct rio_mport *port, u16 destid,
688 	      u8 hopcount)
689 {
690 	u8 port_num, route_port;
691 	int num_ports;
692 	struct rio_dev *rdev;
693 	u16 ndestid;
694 
695 	/* Setup new RIO device */
696 	if ((rdev = rio_setup_device(net, port, destid, hopcount, 0))) {
697 		/* Add device to the global and bus/net specific list. */
698 		list_add_tail(&rdev->net_list, &net->devices);
699 	} else
700 		return -1;
701 
702 	if (rio_is_switch(rdev)) {
703 		next_switchid++;
704 
705 		/* Associated destid is how we accessed this switch */
706 		rdev->rswitch->destid = destid;
707 
708 		num_ports = rio_get_swpinfo_tports(port, destid, hopcount);
709 		pr_debug(
710 		    "RIO: found %s (vid %4.4x did %4.4x) with %d ports\n",
711 		    rio_name(rdev), rdev->vid, rdev->did, num_ports);
712 		for (port_num = 0; port_num < num_ports; port_num++) {
713 			if (rio_get_swpinfo_inport(port, destid, hopcount) ==
714 			    port_num)
715 				continue;
716 
717 			if (rio_sport_is_active
718 			    (port, destid, hopcount, port_num)) {
719 				pr_debug(
720 				    "RIO: scanning device on port %d\n",
721 				    port_num);
722 				for (ndestid = 0; ndestid < RIO_ANY_DESTID;
723 				     ndestid++) {
724 					rio_route_get_entry(port, rdev,
725 							    RIO_GLOBAL_TABLE,
726 							    ndestid,
727 							    &route_port);
728 					if (route_port == port_num)
729 						break;
730 				}
731 
732 				if (rio_disc_peer
733 				    (net, port, ndestid, hopcount + 1) < 0)
734 					return -1;
735 			}
736 		}
737 	} else
738 		pr_debug("RIO: found %s (vid %4.4x did %4.4x)\n",
739 		    rio_name(rdev), rdev->vid, rdev->did);
740 
741 	return 0;
742 }
743 
744 /**
745  * rio_mport_is_active- Tests if master port link is active
746  * @port: Master port to test
747  *
748  * Reads the port error status CSR for the master port to
749  * determine if the port has an active link.  Returns
750  * %PORT_N_ERR_STS_PORT_OK if the  master port is active
751  * or %0 if it is inactive.
752  */
753 static int rio_mport_is_active(struct rio_mport *port)
754 {
755 	u32 result = 0;
756 	u32 ext_ftr_ptr;
757 	int *entry = rio_mport_phys_table;
758 
759 	do {
760 		if ((ext_ftr_ptr =
761 		     rio_mport_get_feature(port, 1, 0, 0, *entry)))
762 			break;
763 	} while (*++entry >= 0);
764 
765 	if (ext_ftr_ptr)
766 		rio_local_read_config_32(port,
767 					 ext_ftr_ptr +
768 					 RIO_PORT_N_ERR_STS_CSR(port->index),
769 					 &result);
770 
771 	return (result & PORT_N_ERR_STS_PORT_OK);
772 }
773 
774 /**
775  * rio_alloc_net- Allocate and configure a new RIO network
776  * @port: Master port associated with the RIO network
777  *
778  * Allocates a RIO network structure, initializes per-network
779  * list heads, and adds the associated master port to the
780  * network list of associated master ports. Returns a
781  * RIO network pointer on success or %NULL on failure.
782  */
783 static struct rio_net __devinit *rio_alloc_net(struct rio_mport *port)
784 {
785 	struct rio_net *net;
786 
787 	net = kmalloc(sizeof(struct rio_net), GFP_KERNEL);
788 	if (net) {
789 		memset(net, 0, sizeof(struct rio_net));
790 		INIT_LIST_HEAD(&net->node);
791 		INIT_LIST_HEAD(&net->devices);
792 		INIT_LIST_HEAD(&net->mports);
793 		list_add_tail(&port->nnode, &net->mports);
794 		net->hport = port;
795 		net->id = next_net++;
796 	}
797 	return net;
798 }
799 
800 /**
801  * rio_enum_mport- Start enumeration through a master port
802  * @mport: Master port to send transactions
803  *
804  * Starts the enumeration process. If somebody has enumerated our
805  * master port device, then give up. If not and we have an active
806  * link, then start recursive peer enumeration. Returns %0 if
807  * enumeration succeeds or %-EBUSY if enumeration fails.
808  */
809 int rio_enum_mport(struct rio_mport *mport)
810 {
811 	struct rio_net *net = NULL;
812 	int rc = 0;
813 
814 	printk(KERN_INFO "RIO: enumerate master port %d, %s\n", mport->id,
815 	       mport->name);
816 	/* If somebody else enumerated our master port device, bail. */
817 	if (rio_enum_host(mport) < 0) {
818 		printk(KERN_INFO
819 		       "RIO: master port %d device has been enumerated by a remote host\n",
820 		       mport->id);
821 		rc = -EBUSY;
822 		goto out;
823 	}
824 
825 	/* If master port has an active link, allocate net and enum peers */
826 	if (rio_mport_is_active(mport)) {
827 		if (!(net = rio_alloc_net(mport))) {
828 			printk(KERN_ERR "RIO: failed to allocate new net\n");
829 			rc = -ENOMEM;
830 			goto out;
831 		}
832 		if (rio_enum_peer(net, mport, 0) < 0) {
833 			/* A higher priority host won enumeration, bail. */
834 			printk(KERN_INFO
835 			       "RIO: master port %d device has lost enumeration to a remote host\n",
836 			       mport->id);
837 			rio_clear_locks(mport);
838 			rc = -EBUSY;
839 			goto out;
840 		}
841 		rio_clear_locks(mport);
842 	} else {
843 		printk(KERN_INFO "RIO: master port %d link inactive\n",
844 		       mport->id);
845 		rc = -EINVAL;
846 	}
847 
848       out:
849 	return rc;
850 }
851 
852 /**
853  * rio_build_route_tables- Generate route tables from switch route entries
854  *
855  * For each switch device, generate a route table by copying existing
856  * route entries from the switch.
857  */
858 static void rio_build_route_tables(void)
859 {
860 	struct rio_dev *rdev;
861 	int i;
862 	u8 sport;
863 
864 	list_for_each_entry(rdev, &rio_devices, global_list)
865 	    if (rio_is_switch(rdev))
866 		for (i = 0; i < RIO_MAX_ROUTE_ENTRIES; i++) {
867 			if (rio_route_get_entry
868 			    (rdev->net->hport, rdev, RIO_GLOBAL_TABLE, i,
869 			     &sport) < 0)
870 				continue;
871 			rdev->rswitch->route_table[i] = sport;
872 		}
873 }
874 
875 /**
876  * rio_enum_timeout- Signal that enumeration timed out
877  * @data: Address of timeout flag.
878  *
879  * When the enumeration complete timer expires, set a flag that
880  * signals to the discovery process that enumeration did not
881  * complete in a sane amount of time.
882  */
883 static void rio_enum_timeout(unsigned long data)
884 {
885 	/* Enumeration timed out, set flag */
886 	*(int *)data = 1;
887 }
888 
889 /**
890  * rio_disc_mport- Start discovery through a master port
891  * @mport: Master port to send transactions
892  *
893  * Starts the discovery process. If we have an active link,
894  * then wait for the signal that enumeration is complete.
895  * When enumeration completion is signaled, start recursive
896  * peer discovery. Returns %0 if discovery succeeds or %-EBUSY
897  * on failure.
898  */
899 int rio_disc_mport(struct rio_mport *mport)
900 {
901 	struct rio_net *net = NULL;
902 	int enum_timeout_flag = 0;
903 
904 	printk(KERN_INFO "RIO: discover master port %d, %s\n", mport->id,
905 	       mport->name);
906 
907 	/* If master port has an active link, allocate net and discover peers */
908 	if (rio_mport_is_active(mport)) {
909 		if (!(net = rio_alloc_net(mport))) {
910 			printk(KERN_ERR "RIO: Failed to allocate new net\n");
911 			goto bail;
912 		}
913 
914 		pr_debug("RIO: wait for enumeration complete...");
915 
916 		rio_enum_timer.expires =
917 		    jiffies + CONFIG_RAPIDIO_DISC_TIMEOUT * HZ;
918 		rio_enum_timer.data = (unsigned long)&enum_timeout_flag;
919 		add_timer(&rio_enum_timer);
920 		while (!rio_enum_complete(mport)) {
921 			mdelay(1);
922 			if (enum_timeout_flag) {
923 				del_timer_sync(&rio_enum_timer);
924 				goto timeout;
925 			}
926 		}
927 		del_timer_sync(&rio_enum_timer);
928 
929 		pr_debug("done\n");
930 		if (rio_disc_peer(net, mport, RIO_ANY_DESTID, 0) < 0) {
931 			printk(KERN_INFO
932 			       "RIO: master port %d device has failed discovery\n",
933 			       mport->id);
934 			goto bail;
935 		}
936 
937 		rio_build_route_tables();
938 	}
939 
940 	return 0;
941 
942       timeout:
943 	pr_debug("timeout\n");
944       bail:
945 	return -EBUSY;
946 }
947