1/*
2 * RapidIO enumeration and discovery support
3 *
4 * Copyright 2005 MontaVista Software, Inc.
5 * Matt Porter <mporter@kernel.crashing.org>
6 *
7 * Copyright 2009 Integrated Device Technology, Inc.
8 * Alex Bounine <alexandre.bounine@idt.com>
9 * - Added Port-Write/Error Management initialization and handling
10 *
11 * Copyright 2009 Sysgo AG
12 * Thomas Moll <thomas.moll@sysgo.com>
13 * - Added Input- Output- enable functionality, to allow full communication
14 *
15 * This program is free software; you can redistribute  it and/or modify it
16 * under  the terms of  the GNU General  Public License as published by the
17 * Free Software Foundation;  either version 2 of the  License, or (at your
18 * option) any later version.
19 */
20
21#include <linux/types.h>
22#include <linux/kernel.h>
23
24#include <linux/delay.h>
25#include <linux/dma-mapping.h>
26#include <linux/init.h>
27#include <linux/rio.h>
28#include <linux/rio_drv.h>
29#include <linux/rio_ids.h>
30#include <linux/rio_regs.h>
31#include <linux/module.h>
32#include <linux/spinlock.h>
33#include <linux/timer.h>
34#include <linux/sched.h>
35#include <linux/jiffies.h>
36#include <linux/slab.h>
37
38#include "rio.h"
39
40static void rio_init_em(struct rio_dev *rdev);
41
42static int next_destid = 0;
43static int next_comptag = 1;
44
45static int rio_mport_phys_table[] = {
46	RIO_EFB_PAR_EP_ID,
47	RIO_EFB_PAR_EP_REC_ID,
48	RIO_EFB_SER_EP_ID,
49	RIO_EFB_SER_EP_REC_ID,
50	-1,
51};
52
53
54/**
55 * rio_destid_alloc - Allocate next available destID for given network
56 * @net: RIO network
57 *
58 * Returns next available device destination ID for the specified RIO network.
59 * Marks allocated ID as one in use.
60 * Returns RIO_INVALID_DESTID if new destID is not available.
61 */
62static u16 rio_destid_alloc(struct rio_net *net)
63{
64	int destid;
65	struct rio_id_table *idtab = &net->destid_table;
66
67	spin_lock(&idtab->lock);
68	destid = find_first_zero_bit(idtab->table, idtab->max);
69
70	if (destid < idtab->max) {
71		set_bit(destid, idtab->table);
72		destid += idtab->start;
73	} else
74		destid = RIO_INVALID_DESTID;
75
76	spin_unlock(&idtab->lock);
77	return (u16)destid;
78}
79
80/**
81 * rio_destid_reserve - Reserve the specivied destID
82 * @net: RIO network
83 * @destid: destID to reserve
84 *
85 * Tries to reserve the specified destID.
86 * Returns 0 if successfull.
87 */
88static int rio_destid_reserve(struct rio_net *net, u16 destid)
89{
90	int oldbit;
91	struct rio_id_table *idtab = &net->destid_table;
92
93	destid -= idtab->start;
94	spin_lock(&idtab->lock);
95	oldbit = test_and_set_bit(destid, idtab->table);
96	spin_unlock(&idtab->lock);
97	return oldbit;
98}
99
100/**
101 * rio_destid_free - free a previously allocated destID
102 * @net: RIO network
103 * @destid: destID to free
104 *
105 * Makes the specified destID available for use.
106 */
107static void rio_destid_free(struct rio_net *net, u16 destid)
108{
109	struct rio_id_table *idtab = &net->destid_table;
110
111	destid -= idtab->start;
112	spin_lock(&idtab->lock);
113	clear_bit(destid, idtab->table);
114	spin_unlock(&idtab->lock);
115}
116
117/**
118 * rio_destid_first - return first destID in use
119 * @net: RIO network
120 */
121static u16 rio_destid_first(struct rio_net *net)
122{
123	int destid;
124	struct rio_id_table *idtab = &net->destid_table;
125
126	spin_lock(&idtab->lock);
127	destid = find_first_bit(idtab->table, idtab->max);
128	if (destid >= idtab->max)
129		destid = RIO_INVALID_DESTID;
130	else
131		destid += idtab->start;
132	spin_unlock(&idtab->lock);
133	return (u16)destid;
134}
135
136/**
137 * rio_destid_next - return next destID in use
138 * @net: RIO network
139 * @from: destination ID from which search shall continue
140 */
141static u16 rio_destid_next(struct rio_net *net, u16 from)
142{
143	int destid;
144	struct rio_id_table *idtab = &net->destid_table;
145
146	spin_lock(&idtab->lock);
147	destid = find_next_bit(idtab->table, idtab->max, from);
148	if (destid >= idtab->max)
149		destid = RIO_INVALID_DESTID;
150	else
151		destid += idtab->start;
152	spin_unlock(&idtab->lock);
153	return (u16)destid;
154}
155
156/**
157 * rio_get_device_id - Get the base/extended device id for a device
158 * @port: RIO master port
159 * @destid: Destination ID of device
160 * @hopcount: Hopcount to device
161 *
162 * Reads the base/extended device id from a device. Returns the
163 * 8/16-bit device ID.
164 */
165static u16 rio_get_device_id(struct rio_mport *port, u16 destid, u8 hopcount)
166{
167	u32 result;
168
169	rio_mport_read_config_32(port, destid, hopcount, RIO_DID_CSR, &result);
170
171	return RIO_GET_DID(port->sys_size, result);
172}
173
174/**
175 * rio_set_device_id - Set the base/extended device id for a device
176 * @port: RIO master port
177 * @destid: Destination ID of device
178 * @hopcount: Hopcount to device
179 * @did: Device ID value to be written
180 *
181 * Writes the base/extended device id from a device.
182 */
183static void rio_set_device_id(struct rio_mport *port, u16 destid, u8 hopcount, u16 did)
184{
185	rio_mport_write_config_32(port, destid, hopcount, RIO_DID_CSR,
186				  RIO_SET_DID(port->sys_size, did));
187}
188
189/**
190 * rio_local_set_device_id - Set the base/extended device id for a port
191 * @port: RIO master port
192 * @did: Device ID value to be written
193 *
194 * Writes the base/extended device id from a device.
195 */
196static void rio_local_set_device_id(struct rio_mport *port, u16 did)
197{
198	rio_local_write_config_32(port, RIO_DID_CSR, RIO_SET_DID(port->sys_size,
199				did));
200}
201
202/**
203 * rio_clear_locks- Release all host locks and signal enumeration complete
204 * @net: RIO network to run on
205 *
206 * Marks the component tag CSR on each device with the enumeration
207 * complete flag. When complete, it then release the host locks on
208 * each device. Returns 0 on success or %-EINVAL on failure.
209 */
210static int rio_clear_locks(struct rio_net *net)
211{
212	struct rio_mport *port = net->hport;
213	struct rio_dev *rdev;
214	u32 result;
215	int ret = 0;
216
217	/* Release host device id locks */
218	rio_local_write_config_32(port, RIO_HOST_DID_LOCK_CSR,
219				  port->host_deviceid);
220	rio_local_read_config_32(port, RIO_HOST_DID_LOCK_CSR, &result);
221	if ((result & 0xffff) != 0xffff) {
222		printk(KERN_INFO
223		       "RIO: badness when releasing host lock on master port, result %8.8x\n",
224		       result);
225		ret = -EINVAL;
226	}
227	list_for_each_entry(rdev, &net->devices, net_list) {
228		rio_write_config_32(rdev, RIO_HOST_DID_LOCK_CSR,
229				    port->host_deviceid);
230		rio_read_config_32(rdev, RIO_HOST_DID_LOCK_CSR, &result);
231		if ((result & 0xffff) != 0xffff) {
232			printk(KERN_INFO
233			       "RIO: badness when releasing host lock on vid %4.4x did %4.4x\n",
234			       rdev->vid, rdev->did);
235			ret = -EINVAL;
236		}
237
238		/* Mark device as discovered and enable master */
239		rio_read_config_32(rdev,
240				   rdev->phys_efptr + RIO_PORT_GEN_CTL_CSR,
241				   &result);
242		result |= RIO_PORT_GEN_DISCOVERED | RIO_PORT_GEN_MASTER;
243		rio_write_config_32(rdev,
244				    rdev->phys_efptr + RIO_PORT_GEN_CTL_CSR,
245				    result);
246	}
247
248	return ret;
249}
250
251/**
252 * rio_enum_host- Set host lock and initialize host destination ID
253 * @port: Master port to issue transaction
254 *
255 * Sets the local host master port lock and destination ID register
256 * with the host device ID value. The host device ID value is provided
257 * by the platform. Returns %0 on success or %-1 on failure.
258 */
259static int rio_enum_host(struct rio_mport *port)
260{
261	u32 result;
262
263	/* Set master port host device id lock */
264	rio_local_write_config_32(port, RIO_HOST_DID_LOCK_CSR,
265				  port->host_deviceid);
266
267	rio_local_read_config_32(port, RIO_HOST_DID_LOCK_CSR, &result);
268	if ((result & 0xffff) != port->host_deviceid)
269		return -1;
270
271	/* Set master port destid and init destid ctr */
272	rio_local_set_device_id(port, port->host_deviceid);
273	return 0;
274}
275
276/**
277 * rio_device_has_destid- Test if a device contains a destination ID register
278 * @port: Master port to issue transaction
279 * @src_ops: RIO device source operations
280 * @dst_ops: RIO device destination operations
281 *
282 * Checks the provided @src_ops and @dst_ops for the necessary transaction
283 * capabilities that indicate whether or not a device will implement a
284 * destination ID register. Returns 1 if true or 0 if false.
285 */
286static int rio_device_has_destid(struct rio_mport *port, int src_ops,
287				 int dst_ops)
288{
289	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;
290
291	return !!((src_ops | dst_ops) & mask);
292}
293
294/**
295 * rio_release_dev- Frees a RIO device struct
296 * @dev: LDM device associated with a RIO device struct
297 *
298 * Gets the RIO device struct associated a RIO device struct.
299 * The RIO device struct is freed.
300 */
301static void rio_release_dev(struct device *dev)
302{
303	struct rio_dev *rdev;
304
305	rdev = to_rio_dev(dev);
306	kfree(rdev);
307}
308
309/**
310 * rio_is_switch- Tests if a RIO device has switch capabilities
311 * @rdev: RIO device
312 *
313 * Gets the RIO device Processing Element Features register
314 * contents and tests for switch capabilities. Returns 1 if
315 * the device is a switch or 0 if it is not a switch.
316 * The RIO device struct is freed.
317 */
318static int rio_is_switch(struct rio_dev *rdev)
319{
320	if (rdev->pef & RIO_PEF_SWITCH)
321		return 1;
322	return 0;
323}
324
325/**
326 * rio_setup_device- Allocates and sets up a RIO device
327 * @net: RIO network
328 * @port: Master port to send transactions
329 * @destid: Current destination ID
330 * @hopcount: Current hopcount
331 * @do_enum: Enumeration/Discovery mode flag
332 *
333 * Allocates a RIO device and configures fields based on configuration
334 * space contents. If device has a destination ID register, a destination
335 * ID is either assigned in enumeration mode or read from configuration
336 * space in discovery mode.  If the device has switch capabilities, then
337 * a switch is allocated and configured appropriately. Returns a pointer
338 * to a RIO device on success or NULL on failure.
339 *
340 */
341static struct rio_dev *rio_setup_device(struct rio_net *net,
342					struct rio_mport *port, u16 destid,
343					u8 hopcount, int do_enum)
344{
345	int ret = 0;
346	struct rio_dev *rdev;
347	struct rio_switch *rswitch = NULL;
348	int result, rdid;
349	size_t size;
350	u32 swpinfo = 0;
351
352	size = sizeof(struct rio_dev);
353	if (rio_mport_read_config_32(port, destid, hopcount,
354				     RIO_PEF_CAR, &result))
355		return NULL;
356
357	if (result & (RIO_PEF_SWITCH | RIO_PEF_MULTIPORT)) {
358		rio_mport_read_config_32(port, destid, hopcount,
359					 RIO_SWP_INFO_CAR, &swpinfo);
360		if (result & RIO_PEF_SWITCH) {
361			size += (RIO_GET_TOTAL_PORTS(swpinfo) *
362				sizeof(rswitch->nextdev[0])) + sizeof(*rswitch);
363		}
364	}
365
366	rdev = kzalloc(size, GFP_KERNEL);
367	if (!rdev)
368		return NULL;
369
370	rdev->net = net;
371	rdev->pef = result;
372	rdev->swpinfo = swpinfo;
373	rio_mport_read_config_32(port, destid, hopcount, RIO_DEV_ID_CAR,
374				 &result);
375	rdev->did = result >> 16;
376	rdev->vid = result & 0xffff;
377	rio_mport_read_config_32(port, destid, hopcount, RIO_DEV_INFO_CAR,
378				 &rdev->device_rev);
379	rio_mport_read_config_32(port, destid, hopcount, RIO_ASM_ID_CAR,
380				 &result);
381	rdev->asm_did = result >> 16;
382	rdev->asm_vid = result & 0xffff;
383	rio_mport_read_config_32(port, destid, hopcount, RIO_ASM_INFO_CAR,
384				 &result);
385	rdev->asm_rev = result >> 16;
386	if (rdev->pef & RIO_PEF_EXT_FEATURES) {
387		rdev->efptr = result & 0xffff;
388		rdev->phys_efptr = rio_mport_get_physefb(port, 0, destid,
389							 hopcount);
390
391		rdev->em_efptr = rio_mport_get_feature(port, 0, destid,
392						hopcount, RIO_EFB_ERR_MGMNT);
393	}
394
395	rio_mport_read_config_32(port, destid, hopcount, RIO_SRC_OPS_CAR,
396				 &rdev->src_ops);
397	rio_mport_read_config_32(port, destid, hopcount, RIO_DST_OPS_CAR,
398				 &rdev->dst_ops);
399
400	if (do_enum) {
401		/* Assign component tag to device */
402		if (next_comptag >= 0x10000) {
403			pr_err("RIO: Component Tag Counter Overflow\n");
404			goto cleanup;
405		}
406		rio_mport_write_config_32(port, destid, hopcount,
407					  RIO_COMPONENT_TAG_CSR, next_comptag);
408		rdev->comp_tag = next_comptag++;
409		rdev->do_enum = true;
410	}  else {
411		rio_mport_read_config_32(port, destid, hopcount,
412					 RIO_COMPONENT_TAG_CSR,
413					 &rdev->comp_tag);
414	}
415
416	if (rio_device_has_destid(port, rdev->src_ops, rdev->dst_ops)) {
417		if (do_enum) {
418			rio_set_device_id(port, destid, hopcount, next_destid);
419			rdev->destid = next_destid;
420			next_destid = rio_destid_alloc(net);
421		} else
422			rdev->destid = rio_get_device_id(port, destid, hopcount);
423
424		rdev->hopcount = 0xff;
425	} else {
426		/* Switch device has an associated destID which
427		 * will be adjusted later
428		 */
429		rdev->destid = destid;
430		rdev->hopcount = hopcount;
431	}
432
433	/* If a PE has both switch and other functions, show it as a switch */
434	if (rio_is_switch(rdev)) {
435		rswitch = rdev->rswitch;
436		rswitch->port_ok = 0;
437		spin_lock_init(&rswitch->lock);
438		rswitch->route_table = kzalloc(sizeof(u8)*
439					RIO_MAX_ROUTE_ENTRIES(port->sys_size),
440					GFP_KERNEL);
441		if (!rswitch->route_table)
442			goto cleanup;
443		/* Initialize switch route table */
444		for (rdid = 0; rdid < RIO_MAX_ROUTE_ENTRIES(port->sys_size);
445				rdid++)
446			rswitch->route_table[rdid] = RIO_INVALID_ROUTE;
447		dev_set_name(&rdev->dev, "%02x:s:%04x", rdev->net->id,
448			     rdev->comp_tag & RIO_CTAG_UDEVID);
449
450		if (do_enum)
451			rio_route_clr_table(rdev, RIO_GLOBAL_TABLE, 0);
452
453		list_add_tail(&rswitch->node, &net->switches);
454
455	} else {
456		if (do_enum)
457			/*Enable Input Output Port (transmitter reviever)*/
458			rio_enable_rx_tx_port(port, 0, destid, hopcount, 0);
459
460		dev_set_name(&rdev->dev, "%02x:e:%04x", rdev->net->id,
461			     rdev->comp_tag & RIO_CTAG_UDEVID);
462	}
463
464	rdev->dev.parent = &port->dev;
465	rio_attach_device(rdev);
466
467	device_initialize(&rdev->dev);
468	rdev->dev.release = rio_release_dev;
469	rio_dev_get(rdev);
470
471	rdev->dma_mask = DMA_BIT_MASK(32);
472	rdev->dev.dma_mask = &rdev->dma_mask;
473	rdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
474
475	if (rdev->dst_ops & RIO_DST_OPS_DOORBELL)
476		rio_init_dbell_res(&rdev->riores[RIO_DOORBELL_RESOURCE],
477				   0, 0xffff);
478
479	ret = rio_add_device(rdev);
480	if (ret)
481		goto cleanup;
482
483	return rdev;
484
485cleanup:
486	if (rswitch)
487		kfree(rswitch->route_table);
488
489	kfree(rdev);
490	return NULL;
491}
492
493/**
494 * rio_sport_is_active- Tests if a switch port has an active connection.
495 * @port: Master port to send transaction
496 * @destid: Associated destination ID for switch
497 * @hopcount: Hopcount to reach switch
498 * @sport: Switch port number
499 *
500 * Reads the port error status CSR for a particular switch port to
501 * determine if the port has an active link.  Returns
502 * %RIO_PORT_N_ERR_STS_PORT_OK if the port is active or %0 if it is
503 * inactive.
504 */
505static int
506rio_sport_is_active(struct rio_mport *port, u16 destid, u8 hopcount, int sport)
507{
508	u32 result = 0;
509	u32 ext_ftr_ptr;
510
511	ext_ftr_ptr = rio_mport_get_efb(port, 0, destid, hopcount, 0);
512
513	while (ext_ftr_ptr) {
514		rio_mport_read_config_32(port, destid, hopcount,
515					 ext_ftr_ptr, &result);
516		result = RIO_GET_BLOCK_ID(result);
517		if ((result == RIO_EFB_SER_EP_FREE_ID) ||
518		    (result == RIO_EFB_SER_EP_FREE_ID_V13P) ||
519		    (result == RIO_EFB_SER_EP_FREC_ID))
520			break;
521
522		ext_ftr_ptr = rio_mport_get_efb(port, 0, destid, hopcount,
523						ext_ftr_ptr);
524	}
525
526	if (ext_ftr_ptr)
527		rio_mport_read_config_32(port, destid, hopcount,
528					 ext_ftr_ptr +
529					 RIO_PORT_N_ERR_STS_CSR(sport),
530					 &result);
531
532	return result & RIO_PORT_N_ERR_STS_PORT_OK;
533}
534
535/**
536 * rio_get_host_deviceid_lock- Reads the Host Device ID Lock CSR on a device
537 * @port: Master port to send transaction
538 * @hopcount: Number of hops to the device
539 *
540 * Used during enumeration to read the Host Device ID Lock CSR on a
541 * RIO device. Returns the value of the lock register.
542 */
543static u16 rio_get_host_deviceid_lock(struct rio_mport *port, u8 hopcount)
544{
545	u32 result;
546
547	rio_mport_read_config_32(port, RIO_ANY_DESTID(port->sys_size), hopcount,
548				 RIO_HOST_DID_LOCK_CSR, &result);
549
550	return (u16) (result & 0xffff);
551}
552
553/**
554 * rio_enum_peer- Recursively enumerate a RIO network through a master port
555 * @net: RIO network being enumerated
556 * @port: Master port to send transactions
557 * @hopcount: Number of hops into the network
558 * @prev: Previous RIO device connected to the enumerated one
559 * @prev_port: Port on previous RIO device
560 *
561 * Recursively enumerates a RIO network.  Transactions are sent via the
562 * master port passed in @port.
563 */
564static int rio_enum_peer(struct rio_net *net, struct rio_mport *port,
565			 u8 hopcount, struct rio_dev *prev, int prev_port)
566{
567	struct rio_dev *rdev;
568	u32 regval;
569	int tmp;
570
571	if (rio_mport_chk_dev_access(port,
572			RIO_ANY_DESTID(port->sys_size), hopcount)) {
573		pr_debug("RIO: device access check failed\n");
574		return -1;
575	}
576
577	if (rio_get_host_deviceid_lock(port, hopcount) == port->host_deviceid) {
578		pr_debug("RIO: PE already discovered by this host\n");
579		/*
580		 * Already discovered by this host. Add it as another
581		 * link to the existing device.
582		 */
583		rio_mport_read_config_32(port, RIO_ANY_DESTID(port->sys_size),
584				hopcount, RIO_COMPONENT_TAG_CSR, &regval);
585
586		if (regval) {
587			rdev = rio_get_comptag((regval & 0xffff), NULL);
588
589			if (rdev && prev && rio_is_switch(prev)) {
590				pr_debug("RIO: redundant path to %s\n",
591					 rio_name(rdev));
592				prev->rswitch->nextdev[prev_port] = rdev;
593			}
594		}
595
596		return 0;
597	}
598
599	/* Attempt to acquire device lock */
600	rio_mport_write_config_32(port, RIO_ANY_DESTID(port->sys_size),
601				  hopcount,
602				  RIO_HOST_DID_LOCK_CSR, port->host_deviceid);
603	while ((tmp = rio_get_host_deviceid_lock(port, hopcount))
604	       < port->host_deviceid) {
605		/* Delay a bit */
606		mdelay(1);
607		/* Attempt to acquire device lock again */
608		rio_mport_write_config_32(port, RIO_ANY_DESTID(port->sys_size),
609					  hopcount,
610					  RIO_HOST_DID_LOCK_CSR,
611					  port->host_deviceid);
612	}
613
614	if (rio_get_host_deviceid_lock(port, hopcount) > port->host_deviceid) {
615		pr_debug(
616		    "RIO: PE locked by a higher priority host...retreating\n");
617		return -1;
618	}
619
620	/* Setup new RIO device */
621	rdev = rio_setup_device(net, port, RIO_ANY_DESTID(port->sys_size),
622					hopcount, 1);
623	if (rdev) {
624		/* Add device to the global and bus/net specific list. */
625		list_add_tail(&rdev->net_list, &net->devices);
626		rdev->prev = prev;
627		if (prev && rio_is_switch(prev))
628			prev->rswitch->nextdev[prev_port] = rdev;
629	} else
630		return -1;
631
632	if (rio_is_switch(rdev)) {
633		int sw_destid;
634		int cur_destid;
635		int sw_inport;
636		u16 destid;
637		int port_num;
638
639		sw_inport = RIO_GET_PORT_NUM(rdev->swpinfo);
640		rio_route_add_entry(rdev, RIO_GLOBAL_TABLE,
641				    port->host_deviceid, sw_inport, 0);
642		rdev->rswitch->route_table[port->host_deviceid] = sw_inport;
643
644		destid = rio_destid_first(net);
645		while (destid != RIO_INVALID_DESTID && destid < next_destid) {
646			if (destid != port->host_deviceid) {
647				rio_route_add_entry(rdev, RIO_GLOBAL_TABLE,
648						    destid, sw_inport, 0);
649				rdev->rswitch->route_table[destid] = sw_inport;
650			}
651			destid = rio_destid_next(net, destid + 1);
652		}
653		pr_debug(
654		    "RIO: found %s (vid %4.4x did %4.4x) with %d ports\n",
655		    rio_name(rdev), rdev->vid, rdev->did,
656		    RIO_GET_TOTAL_PORTS(rdev->swpinfo));
657		sw_destid = next_destid;
658		for (port_num = 0;
659		     port_num < RIO_GET_TOTAL_PORTS(rdev->swpinfo);
660		     port_num++) {
661			if (sw_inport == port_num) {
662				rio_enable_rx_tx_port(port, 0,
663					      RIO_ANY_DESTID(port->sys_size),
664					      hopcount, port_num);
665				rdev->rswitch->port_ok |= (1 << port_num);
666				continue;
667			}
668
669			cur_destid = next_destid;
670
671			if (rio_sport_is_active
672			    (port, RIO_ANY_DESTID(port->sys_size), hopcount,
673			     port_num)) {
674				pr_debug(
675				    "RIO: scanning device on port %d\n",
676				    port_num);
677				rio_enable_rx_tx_port(port, 0,
678					      RIO_ANY_DESTID(port->sys_size),
679					      hopcount, port_num);
680				rdev->rswitch->port_ok |= (1 << port_num);
681				rio_route_add_entry(rdev, RIO_GLOBAL_TABLE,
682						RIO_ANY_DESTID(port->sys_size),
683						port_num, 0);
684
685				if (rio_enum_peer(net, port, hopcount + 1,
686						  rdev, port_num) < 0)
687					return -1;
688
689				/* Update routing tables */
690				destid = rio_destid_next(net, cur_destid + 1);
691				if (destid != RIO_INVALID_DESTID) {
692					for (destid = cur_destid;
693					     destid < next_destid;) {
694						if (destid != port->host_deviceid) {
695							rio_route_add_entry(rdev,
696								    RIO_GLOBAL_TABLE,
697								    destid,
698								    port_num,
699								    0);
700							rdev->rswitch->
701								route_table[destid] =
702								port_num;
703						}
704						destid = rio_destid_next(net,
705								destid + 1);
706					}
707				}
708			} else {
709				/* If switch supports Error Management,
710				 * set PORT_LOCKOUT bit for unused port
711				 */
712				if (rdev->em_efptr)
713					rio_set_port_lockout(rdev, port_num, 1);
714
715				rdev->rswitch->port_ok &= ~(1 << port_num);
716			}
717		}
718
719		/* Direct Port-write messages to the enumeratiing host */
720		if ((rdev->src_ops & RIO_SRC_OPS_PORT_WRITE) &&
721		    (rdev->em_efptr)) {
722			rio_write_config_32(rdev,
723					rdev->em_efptr + RIO_EM_PW_TGT_DEVID,
724					(port->host_deviceid << 16) |
725					(port->sys_size << 15));
726		}
727
728		rio_init_em(rdev);
729
730		/* Check for empty switch */
731		if (next_destid == sw_destid)
732			next_destid = rio_destid_alloc(net);
733
734		rdev->destid = sw_destid;
735	} else
736		pr_debug("RIO: found %s (vid %4.4x did %4.4x)\n",
737		    rio_name(rdev), rdev->vid, rdev->did);
738
739	return 0;
740}
741
742/**
743 * rio_enum_complete- Tests if enumeration of a network is complete
744 * @port: Master port to send transaction
745 *
746 * Tests the PGCCSR discovered bit for non-zero value (enumeration
747 * complete flag). Return %1 if enumeration is complete or %0 if
748 * enumeration is incomplete.
749 */
750static int rio_enum_complete(struct rio_mport *port)
751{
752	u32 regval;
753
754	rio_local_read_config_32(port, port->phys_efptr + RIO_PORT_GEN_CTL_CSR,
755				 &regval);
756	return (regval & RIO_PORT_GEN_DISCOVERED) ? 1 : 0;
757}
758
759/**
760 * rio_disc_peer- Recursively discovers a RIO network through a master port
761 * @net: RIO network being discovered
762 * @port: Master port to send transactions
763 * @destid: Current destination ID in network
764 * @hopcount: Number of hops into the network
765 * @prev: previous rio_dev
766 * @prev_port: previous port number
767 *
768 * Recursively discovers a RIO network.  Transactions are sent via the
769 * master port passed in @port.
770 */
771static int
772rio_disc_peer(struct rio_net *net, struct rio_mport *port, u16 destid,
773	      u8 hopcount, struct rio_dev *prev, int prev_port)
774{
775	u8 port_num, route_port;
776	struct rio_dev *rdev;
777	u16 ndestid;
778
779	/* Setup new RIO device */
780	if ((rdev = rio_setup_device(net, port, destid, hopcount, 0))) {
781		/* Add device to the global and bus/net specific list. */
782		list_add_tail(&rdev->net_list, &net->devices);
783		rdev->prev = prev;
784		if (prev && rio_is_switch(prev))
785			prev->rswitch->nextdev[prev_port] = rdev;
786	} else
787		return -1;
788
789	if (rio_is_switch(rdev)) {
790		/* Associated destid is how we accessed this switch */
791		rdev->destid = destid;
792
793		pr_debug(
794		    "RIO: found %s (vid %4.4x did %4.4x) with %d ports\n",
795		    rio_name(rdev), rdev->vid, rdev->did,
796		    RIO_GET_TOTAL_PORTS(rdev->swpinfo));
797		for (port_num = 0;
798		     port_num < RIO_GET_TOTAL_PORTS(rdev->swpinfo);
799		     port_num++) {
800			if (RIO_GET_PORT_NUM(rdev->swpinfo) == port_num)
801				continue;
802
803			if (rio_sport_is_active
804			    (port, destid, hopcount, port_num)) {
805				pr_debug(
806				    "RIO: scanning device on port %d\n",
807				    port_num);
808
809				rio_lock_device(port, destid, hopcount, 1000);
810
811				for (ndestid = 0;
812				     ndestid < RIO_ANY_DESTID(port->sys_size);
813				     ndestid++) {
814					rio_route_get_entry(rdev,
815							    RIO_GLOBAL_TABLE,
816							    ndestid,
817							    &route_port, 0);
818					if (route_port == port_num)
819						break;
820				}
821
822				if (ndestid == RIO_ANY_DESTID(port->sys_size))
823					continue;
824				rio_unlock_device(port, destid, hopcount);
825				if (rio_disc_peer(net, port, ndestid,
826					hopcount + 1, rdev, port_num) < 0)
827					return -1;
828			}
829		}
830	} else
831		pr_debug("RIO: found %s (vid %4.4x did %4.4x)\n",
832		    rio_name(rdev), rdev->vid, rdev->did);
833
834	return 0;
835}
836
837/**
838 * rio_mport_is_active- Tests if master port link is active
839 * @port: Master port to test
840 *
841 * Reads the port error status CSR for the master port to
842 * determine if the port has an active link.  Returns
843 * %RIO_PORT_N_ERR_STS_PORT_OK if the  master port is active
844 * or %0 if it is inactive.
845 */
846static int rio_mport_is_active(struct rio_mport *port)
847{
848	u32 result = 0;
849	u32 ext_ftr_ptr;
850	int *entry = rio_mport_phys_table;
851
852	do {
853		if ((ext_ftr_ptr =
854		     rio_mport_get_feature(port, 1, 0, 0, *entry)))
855			break;
856	} while (*++entry >= 0);
857
858	if (ext_ftr_ptr)
859		rio_local_read_config_32(port,
860					 ext_ftr_ptr +
861					 RIO_PORT_N_ERR_STS_CSR(port->index),
862					 &result);
863
864	return result & RIO_PORT_N_ERR_STS_PORT_OK;
865}
866
867/**
868 * rio_alloc_net- Allocate and configure a new RIO network
869 * @port: Master port associated with the RIO network
870 * @do_enum: Enumeration/Discovery mode flag
871 * @start: logical minimal start id for new net
872 *
873 * Allocates a RIO network structure, initializes per-network
874 * list heads, and adds the associated master port to the
875 * network list of associated master ports. Returns a
876 * RIO network pointer on success or %NULL on failure.
877 */
878static struct rio_net *rio_alloc_net(struct rio_mport *port,
879					       int do_enum, u16 start)
880{
881	struct rio_net *net;
882
883	net = kzalloc(sizeof(struct rio_net), GFP_KERNEL);
884	if (net && do_enum) {
885		net->destid_table.table = kcalloc(
886			BITS_TO_LONGS(RIO_MAX_ROUTE_ENTRIES(port->sys_size)),
887			sizeof(long),
888			GFP_KERNEL);
889
890		if (net->destid_table.table == NULL) {
891			pr_err("RIO: failed to allocate destID table\n");
892			kfree(net);
893			net = NULL;
894		} else {
895			net->destid_table.start = start;
896			net->destid_table.max =
897					RIO_MAX_ROUTE_ENTRIES(port->sys_size);
898			spin_lock_init(&net->destid_table.lock);
899		}
900	}
901
902	if (net) {
903		INIT_LIST_HEAD(&net->node);
904		INIT_LIST_HEAD(&net->devices);
905		INIT_LIST_HEAD(&net->switches);
906		INIT_LIST_HEAD(&net->mports);
907		list_add_tail(&port->nnode, &net->mports);
908		net->hport = port;
909		net->id = port->id;
910	}
911	return net;
912}
913
914/**
915 * rio_update_route_tables- Updates route tables in switches
916 * @net: RIO network to run update on
917 *
918 * For each enumerated device, ensure that each switch in a system
919 * has correct routing entries. Add routes for devices that where
920 * unknown dirung the first enumeration pass through the switch.
921 */
922static void rio_update_route_tables(struct rio_net *net)
923{
924	struct rio_dev *rdev, *swrdev;
925	struct rio_switch *rswitch;
926	u8 sport;
927	u16 destid;
928
929	list_for_each_entry(rdev, &net->devices, net_list) {
930
931		destid = rdev->destid;
932
933		list_for_each_entry(rswitch, &net->switches, node) {
934
935			if (rio_is_switch(rdev)	&& (rdev->rswitch == rswitch))
936				continue;
937
938			if (RIO_INVALID_ROUTE == rswitch->route_table[destid]) {
939				swrdev = sw_to_rio_dev(rswitch);
940
941				/* Skip if destid ends in empty switch*/
942				if (swrdev->destid == destid)
943					continue;
944
945				sport = RIO_GET_PORT_NUM(swrdev->swpinfo);
946
947				rio_route_add_entry(swrdev, RIO_GLOBAL_TABLE,
948						    destid, sport, 0);
949				rswitch->route_table[destid] = sport;
950			}
951		}
952	}
953}
954
955/**
956 * rio_init_em - Initializes RIO Error Management (for switches)
957 * @rdev: RIO device
958 *
959 * For each enumerated switch, call device-specific error management
960 * initialization routine (if supplied by the switch driver).
961 */
962static void rio_init_em(struct rio_dev *rdev)
963{
964	if (rio_is_switch(rdev) && (rdev->em_efptr) &&
965	    rdev->rswitch->ops && rdev->rswitch->ops->em_init) {
966		rdev->rswitch->ops->em_init(rdev);
967	}
968}
969
970/**
971 * rio_pw_enable - Enables/disables port-write handling by a master port
972 * @port: Master port associated with port-write handling
973 * @enable:  1=enable,  0=disable
974 */
975static void rio_pw_enable(struct rio_mport *port, int enable)
976{
977	if (port->ops->pwenable)
978		port->ops->pwenable(port, enable);
979}
980
981/**
982 * rio_enum_mport- Start enumeration through a master port
983 * @mport: Master port to send transactions
984 * @flags: Enumeration control flags
985 *
986 * Starts the enumeration process. If somebody has enumerated our
987 * master port device, then give up. If not and we have an active
988 * link, then start recursive peer enumeration. Returns %0 if
989 * enumeration succeeds or %-EBUSY if enumeration fails.
990 */
991static int rio_enum_mport(struct rio_mport *mport, u32 flags)
992{
993	struct rio_net *net = NULL;
994	int rc = 0;
995
996	printk(KERN_INFO "RIO: enumerate master port %d, %s\n", mport->id,
997	       mport->name);
998
999	/*
1000	 * To avoid multiple start requests (repeat enumeration is not supported
1001	 * by this method) check if enumeration/discovery was performed for this
1002	 * mport: if mport was added into the list of mports for a net exit
1003	 * with error.
1004	 */
1005	if (mport->nnode.next || mport->nnode.prev)
1006		return -EBUSY;
1007
1008	/* If somebody else enumerated our master port device, bail. */
1009	if (rio_enum_host(mport) < 0) {
1010		printk(KERN_INFO
1011		       "RIO: master port %d device has been enumerated by a remote host\n",
1012		       mport->id);
1013		rc = -EBUSY;
1014		goto out;
1015	}
1016
1017	/* If master port has an active link, allocate net and enum peers */
1018	if (rio_mport_is_active(mport)) {
1019		net = rio_alloc_net(mport, 1, 0);
1020		if (!net) {
1021			printk(KERN_ERR "RIO: failed to allocate new net\n");
1022			rc = -ENOMEM;
1023			goto out;
1024		}
1025
1026		/* reserve mport destID in new net */
1027		rio_destid_reserve(net, mport->host_deviceid);
1028
1029		/* Enable Input Output Port (transmitter reviever) */
1030		rio_enable_rx_tx_port(mport, 1, 0, 0, 0);
1031
1032		/* Set component tag for host */
1033		rio_local_write_config_32(mport, RIO_COMPONENT_TAG_CSR,
1034					  next_comptag++);
1035
1036		next_destid = rio_destid_alloc(net);
1037
1038		if (rio_enum_peer(net, mport, 0, NULL, 0) < 0) {
1039			/* A higher priority host won enumeration, bail. */
1040			printk(KERN_INFO
1041			       "RIO: master port %d device has lost enumeration to a remote host\n",
1042			       mport->id);
1043			rio_clear_locks(net);
1044			rc = -EBUSY;
1045			goto out;
1046		}
1047		/* free the last allocated destID (unused) */
1048		rio_destid_free(net, next_destid);
1049		rio_update_route_tables(net);
1050		rio_clear_locks(net);
1051		rio_pw_enable(mport, 1);
1052	} else {
1053		printk(KERN_INFO "RIO: master port %d link inactive\n",
1054		       mport->id);
1055		rc = -EINVAL;
1056	}
1057
1058      out:
1059	return rc;
1060}
1061
1062/**
1063 * rio_build_route_tables- Generate route tables from switch route entries
1064 * @net: RIO network to run route tables scan on
1065 *
1066 * For each switch device, generate a route table by copying existing
1067 * route entries from the switch.
1068 */
1069static void rio_build_route_tables(struct rio_net *net)
1070{
1071	struct rio_switch *rswitch;
1072	struct rio_dev *rdev;
1073	int i;
1074	u8 sport;
1075
1076	list_for_each_entry(rswitch, &net->switches, node) {
1077		rdev = sw_to_rio_dev(rswitch);
1078
1079		rio_lock_device(net->hport, rdev->destid,
1080				rdev->hopcount, 1000);
1081		for (i = 0;
1082		     i < RIO_MAX_ROUTE_ENTRIES(net->hport->sys_size);
1083		     i++) {
1084			if (rio_route_get_entry(rdev, RIO_GLOBAL_TABLE,
1085						i, &sport, 0) < 0)
1086				continue;
1087			rswitch->route_table[i] = sport;
1088		}
1089
1090		rio_unlock_device(net->hport, rdev->destid, rdev->hopcount);
1091	}
1092}
1093
1094/**
1095 * rio_disc_mport- Start discovery through a master port
1096 * @mport: Master port to send transactions
1097 * @flags: discovery control flags
1098 *
1099 * Starts the discovery process. If we have an active link,
1100 * then wait for the signal that enumeration is complete (if wait
1101 * is allowed).
1102 * When enumeration completion is signaled, start recursive
1103 * peer discovery. Returns %0 if discovery succeeds or %-EBUSY
1104 * on failure.
1105 */
1106static int rio_disc_mport(struct rio_mport *mport, u32 flags)
1107{
1108	struct rio_net *net = NULL;
1109	unsigned long to_end;
1110
1111	printk(KERN_INFO "RIO: discover master port %d, %s\n", mport->id,
1112	       mport->name);
1113
1114	/* If master port has an active link, allocate net and discover peers */
1115	if (rio_mport_is_active(mport)) {
1116		if (rio_enum_complete(mport))
1117			goto enum_done;
1118		else if (flags & RIO_SCAN_ENUM_NO_WAIT)
1119			return -EAGAIN;
1120
1121		pr_debug("RIO: wait for enumeration to complete...\n");
1122
1123		to_end = jiffies + CONFIG_RAPIDIO_DISC_TIMEOUT * HZ;
1124		while (time_before(jiffies, to_end)) {
1125			if (rio_enum_complete(mport))
1126				goto enum_done;
1127			msleep(10);
1128		}
1129
1130		pr_debug("RIO: discovery timeout on mport %d %s\n",
1131			 mport->id, mport->name);
1132		goto bail;
1133enum_done:
1134		pr_debug("RIO: ... enumeration done\n");
1135
1136		net = rio_alloc_net(mport, 0, 0);
1137		if (!net) {
1138			printk(KERN_ERR "RIO: Failed to allocate new net\n");
1139			goto bail;
1140		}
1141
1142		/* Read DestID assigned by enumerator */
1143		rio_local_read_config_32(mport, RIO_DID_CSR,
1144					 &mport->host_deviceid);
1145		mport->host_deviceid = RIO_GET_DID(mport->sys_size,
1146						   mport->host_deviceid);
1147
1148		if (rio_disc_peer(net, mport, RIO_ANY_DESTID(mport->sys_size),
1149					0, NULL, 0) < 0) {
1150			printk(KERN_INFO
1151			       "RIO: master port %d device has failed discovery\n",
1152			       mport->id);
1153			goto bail;
1154		}
1155
1156		rio_build_route_tables(net);
1157	}
1158
1159	return 0;
1160bail:
1161	return -EBUSY;
1162}
1163
1164static struct rio_scan rio_scan_ops = {
1165	.owner = THIS_MODULE,
1166	.enumerate = rio_enum_mport,
1167	.discover = rio_disc_mport,
1168};
1169
1170static bool scan;
1171module_param(scan, bool, 0);
1172MODULE_PARM_DESC(scan, "Start RapidIO network enumeration/discovery "
1173			"(default = 0)");
1174
1175/**
1176 * rio_basic_attach:
1177 *
1178 * When this enumeration/discovery method is loaded as a module this function
1179 * registers its specific enumeration and discover routines for all available
1180 * RapidIO mport devices. The "scan" command line parameter controls ability of
1181 * the module to start RapidIO enumeration/discovery automatically.
1182 *
1183 * Returns 0 for success or -EIO if unable to register itself.
1184 *
1185 * This enumeration/discovery method cannot be unloaded and therefore does not
1186 * provide a matching cleanup_module routine.
1187 */
1188
1189static int __init rio_basic_attach(void)
1190{
1191	if (rio_register_scan(RIO_MPORT_ANY, &rio_scan_ops))
1192		return -EIO;
1193	if (scan)
1194		rio_init_mports();
1195	return 0;
1196}
1197
1198late_initcall(rio_basic_attach);
1199
1200MODULE_DESCRIPTION("Basic RapidIO enumeration/discovery");
1201MODULE_LICENSE("GPL");
1202