1/*
2 * IEEE 1394 for Linux
3 *
4 * Low level (host adapter) management.
5 *
6 * Copyright (C) 1999 Andreas E. Bombe
7 * Copyright (C) 1999 Emanuel Pirker
8 *
9 * This code is licensed under the GPL.  See the file COPYING in the root
10 * directory of the kernel sources for details.
11 */
12
13#include <linux/module.h>
14#include <linux/types.h>
15#include <linux/list.h>
16#include <linux/init.h>
17#include <linux/slab.h>
18#include <linux/timer.h>
19#include <linux/jiffies.h>
20#include <linux/mutex.h>
21
22#include "csr1212.h"
23#include "ieee1394.h"
24#include "ieee1394_types.h"
25#include "hosts.h"
26#include "ieee1394_core.h"
27#include "highlevel.h"
28#include "nodemgr.h"
29#include "csr.h"
30#include "config_roms.h"
31
32
33static void delayed_reset_bus(struct work_struct *work)
34{
35	struct hpsb_host *host =
36		container_of(work, struct hpsb_host, delayed_reset.work);
37	int generation = host->csr.generation + 1;
38
39	/* The generation field rolls over to 2 rather than 0 per IEEE
40	 * 1394a-2000. */
41	if (generation > 0xf || generation < 2)
42		generation = 2;
43
44	CSR_SET_BUS_INFO_GENERATION(host->csr.rom, generation);
45	if (csr1212_generate_csr_image(host->csr.rom) != CSR1212_SUCCESS) {
46		/* CSR image creation failed.
47		 * Reset generation field and do not issue a bus reset. */
48		CSR_SET_BUS_INFO_GENERATION(host->csr.rom,
49					    host->csr.generation);
50		return;
51	}
52
53	host->csr.generation = generation;
54
55	host->update_config_rom = 0;
56	if (host->driver->set_hw_config_rom)
57		host->driver->set_hw_config_rom(host,
58						host->csr.rom->bus_info_data);
59
60	host->csr.gen_timestamp[host->csr.generation] = jiffies;
61	hpsb_reset_bus(host, SHORT_RESET);
62}
63
64static int dummy_transmit_packet(struct hpsb_host *h, struct hpsb_packet *p)
65{
66	return 0;
67}
68
69static int dummy_devctl(struct hpsb_host *h, enum devctl_cmd c, int arg)
70{
71	return -1;
72}
73
74static int dummy_isoctl(struct hpsb_iso *iso, enum isoctl_cmd command,
75			unsigned long arg)
76{
77	return -1;
78}
79
80static struct hpsb_host_driver dummy_driver = {
81	.transmit_packet = dummy_transmit_packet,
82	.devctl =	   dummy_devctl,
83	.isoctl =	   dummy_isoctl
84};
85
86static int alloc_hostnum_cb(struct hpsb_host *host, void *__data)
87{
88	int *hostnum = __data;
89
90	if (host->id == *hostnum)
91		return 1;
92
93	return 0;
94}
95
96static DEFINE_MUTEX(host_num_alloc);
97
98/**
99 * hpsb_alloc_host - allocate a new host controller.
100 * @drv: the driver that will manage the host controller
101 * @extra: number of extra bytes to allocate for the driver
102 *
103 * Allocate a &hpsb_host and initialize the general subsystem specific
104 * fields.  If the driver needs to store per host data, as drivers
105 * usually do, the amount of memory required can be specified by the
106 * @extra parameter.  Once allocated, the driver should initialize the
107 * driver specific parts, enable the controller and make it available
108 * to the general subsystem using hpsb_add_host().
109 *
110 * Return Value: a pointer to the &hpsb_host if successful, %NULL if
111 * no memory was available.
112 */
113struct hpsb_host *hpsb_alloc_host(struct hpsb_host_driver *drv, size_t extra,
114				  struct device *dev)
115{
116	struct hpsb_host *h;
117	int i;
118	int hostnum = 0;
119
120	h = kzalloc(sizeof(*h) + extra, GFP_KERNEL);
121	if (!h)
122		return NULL;
123
124	h->csr.rom = csr1212_create_csr(&csr_bus_ops, CSR_BUS_INFO_SIZE, h);
125	if (!h->csr.rom)
126		goto fail;
127
128	h->hostdata = h + 1;
129	h->driver = drv;
130
131	INIT_LIST_HEAD(&h->pending_packets);
132	INIT_LIST_HEAD(&h->addr_space);
133
134	for (i = 2; i < 16; i++)
135		h->csr.gen_timestamp[i] = jiffies - 60 * HZ;
136
137	atomic_set(&h->generation, 0);
138
139	INIT_DELAYED_WORK(&h->delayed_reset, delayed_reset_bus);
140
141	init_timer(&h->timeout);
142	h->timeout.data = (unsigned long) h;
143	h->timeout.function = abort_timedouts;
144	h->timeout_interval = HZ / 20; /* 50ms, half of minimum SPLIT_TIMEOUT */
145
146	h->topology_map = h->csr.topology_map + 3;
147	h->speed_map = (u8 *)(h->csr.speed_map + 2);
148
149	mutex_lock(&host_num_alloc);
150	while (nodemgr_for_each_host(&hostnum, alloc_hostnum_cb))
151		hostnum++;
152	mutex_unlock(&host_num_alloc);
153	h->id = hostnum;
154
155	memcpy(&h->device, &nodemgr_dev_template_host, sizeof(h->device));
156	h->device.parent = dev;
157	snprintf(h->device.bus_id, BUS_ID_SIZE, "fw-host%d", h->id);
158
159	h->class_dev.dev = &h->device;
160	h->class_dev.class = &hpsb_host_class;
161	snprintf(h->class_dev.class_id, BUS_ID_SIZE, "fw-host%d", h->id);
162
163	if (device_register(&h->device))
164		goto fail;
165	if (class_device_register(&h->class_dev)) {
166		device_unregister(&h->device);
167		goto fail;
168	}
169	get_device(&h->device);
170
171	return h;
172
173fail:
174	kfree(h);
175	return NULL;
176}
177
178int hpsb_add_host(struct hpsb_host *host)
179{
180	if (hpsb_default_host_entry(host))
181		return -ENOMEM;
182
183	highlevel_add_host(host);
184	return 0;
185}
186
187void hpsb_resume_host(struct hpsb_host *host)
188{
189	if (host->driver->set_hw_config_rom)
190		host->driver->set_hw_config_rom(host,
191						host->csr.rom->bus_info_data);
192	host->driver->devctl(host, RESET_BUS, SHORT_RESET);
193}
194
195void hpsb_remove_host(struct hpsb_host *host)
196{
197	host->is_shutdown = 1;
198
199	cancel_delayed_work(&host->delayed_reset);
200	flush_scheduled_work();
201
202	host->driver = &dummy_driver;
203	highlevel_remove_host(host);
204
205	class_device_unregister(&host->class_dev);
206	device_unregister(&host->device);
207}
208
209/**
210 * hpsb_update_config_rom_image - updates configuration ROM image of a host
211 *
212 * Updates the configuration ROM image of a host.  rom_version must be the
213 * current version, otherwise it will fail with return value -1. If this
214 * host does not support config-rom-update, it will return -%EINVAL.
215 * Return value 0 indicates success.
216 */
217int hpsb_update_config_rom_image(struct hpsb_host *host)
218{
219	unsigned long reset_delay;
220	int next_gen = host->csr.generation + 1;
221
222	if (!host->update_config_rom)
223		return -EINVAL;
224
225	if (next_gen > 0xf)
226		next_gen = 2;
227
228	/* Stop the delayed interrupt, we're about to change the config rom and
229	 * it would be a waste to do a bus reset twice. */
230	cancel_delayed_work(&host->delayed_reset);
231
232	/* IEEE 1394a-2000 prohibits using the same generation number
233	 * twice in a 60 second period. */
234	if (time_before(jiffies, host->csr.gen_timestamp[next_gen] + 60 * HZ))
235		/* Wait 60 seconds from the last time this generation number was
236		 * used. */
237		reset_delay =
238			(60 * HZ) + host->csr.gen_timestamp[next_gen] - jiffies;
239	else
240		/* Wait 1 second in case some other code wants to change the
241		 * Config ROM in the near future. */
242		reset_delay = HZ;
243
244	PREPARE_DELAYED_WORK(&host->delayed_reset, delayed_reset_bus);
245	schedule_delayed_work(&host->delayed_reset, reset_delay);
246
247	return 0;
248}
249