1 // SPDX-License-Identifier: GPL-2.0
3 * Thunderbolt Cactus Ridge driver - bus logic (NHI independent)
5 * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
8 #include <linux/slab.h>
9 #include <linux/errno.h>
10 #include <linux/delay.h>
11 #include <linux/platform_data/x86/apple.h>
15 #include "tunnel_pci.h"
18 * struct tb_cm - Simple Thunderbolt connection manager
19 * @tunnel_list: List of active tunnels
20 * @hotplug_active: tb_handle_hotplug will stop progressing plug
21 * events and exit if this is not set (it needs to
22 * acquire the lock one more time). Used to drain wq
23 * after cfg has been paused.
26 struct list_head tunnel_list;
30 /* enumeration & hot plug handling */
33 static void tb_scan_port(struct tb_port *port);
36 * tb_scan_switch() - scan for and initialize downstream switches
38 static void tb_scan_switch(struct tb_switch *sw)
41 for (i = 1; i <= sw->config.max_port_number; i++)
42 tb_scan_port(&sw->ports[i]);
46 * tb_scan_port() - check for and initialize switches below port
48 static void tb_scan_port(struct tb_port *port)
51 if (tb_is_upstream_port(port))
53 if (port->config.type != TB_TYPE_PORT)
55 if (port->dual_link_port && port->link_nr)
57 * Downstream switch is reachable through two ports.
58 * Only scan on the primary port (link_nr == 0).
60 if (tb_wait_for_port(port, false) <= 0)
63 tb_port_WARN(port, "port already has a remote!\n");
66 sw = tb_switch_alloc(port->sw->tb, &port->sw->dev,
67 tb_downstream_route(port));
71 if (tb_switch_configure(sw)) {
76 sw->authorized = true;
78 if (tb_switch_add(sw)) {
83 port->remote = tb_upstream_port(sw);
84 tb_upstream_port(sw)->remote = port;
89 * tb_free_invalid_tunnels() - destroy tunnels of devices that have gone away
91 static void tb_free_invalid_tunnels(struct tb *tb)
93 struct tb_cm *tcm = tb_priv(tb);
94 struct tb_pci_tunnel *tunnel;
95 struct tb_pci_tunnel *n;
97 list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
98 if (tb_pci_is_invalid(tunnel)) {
99 tb_pci_deactivate(tunnel);
100 list_del(&tunnel->list);
107 * tb_free_unplugged_children() - traverse hierarchy and free unplugged switches
109 static void tb_free_unplugged_children(struct tb_switch *sw)
112 for (i = 1; i <= sw->config.max_port_number; i++) {
113 struct tb_port *port = &sw->ports[i];
114 if (tb_is_upstream_port(port))
118 if (port->remote->sw->is_unplugged) {
119 tb_switch_remove(port->remote->sw);
122 tb_free_unplugged_children(port->remote->sw);
129 * find_pci_up_port() - return the first PCIe up port on @sw or NULL
131 static struct tb_port *tb_find_pci_up_port(struct tb_switch *sw)
134 for (i = 1; i <= sw->config.max_port_number; i++)
135 if (sw->ports[i].config.type == TB_TYPE_PCIE_UP)
136 return &sw->ports[i];
141 * find_unused_down_port() - return the first inactive PCIe down port on @sw
143 static struct tb_port *tb_find_unused_down_port(struct tb_switch *sw)
149 for (i = 1; i <= sw->config.max_port_number; i++) {
150 if (tb_is_upstream_port(&sw->ports[i]))
152 if (sw->ports[i].config.type != TB_TYPE_PCIE_DOWN)
154 cap = tb_port_find_cap(&sw->ports[i], TB_PORT_CAP_ADAP);
157 res = tb_port_read(&sw->ports[i], &data, TB_CFG_PORT, cap, 1);
160 if (data & 0x80000000)
162 return &sw->ports[i];
168 * tb_activate_pcie_devices() - scan for and activate PCIe devices
170 * This method is somewhat ad hoc. For now it only supports one device
171 * per port and only devices at depth 1.
173 static void tb_activate_pcie_devices(struct tb *tb)
178 struct tb_switch *sw;
179 struct tb_port *up_port;
180 struct tb_port *down_port;
181 struct tb_pci_tunnel *tunnel;
182 struct tb_cm *tcm = tb_priv(tb);
184 /* scan for pcie devices at depth 1*/
185 for (i = 1; i <= tb->root_switch->config.max_port_number; i++) {
186 if (tb_is_upstream_port(&tb->root_switch->ports[i]))
188 if (tb->root_switch->ports[i].config.type != TB_TYPE_PORT)
190 if (!tb->root_switch->ports[i].remote)
192 sw = tb->root_switch->ports[i].remote->sw;
193 up_port = tb_find_pci_up_port(sw);
195 tb_sw_info(sw, "no PCIe devices found, aborting\n");
199 /* check whether port is already activated */
200 cap = tb_port_find_cap(up_port, TB_PORT_CAP_ADAP);
203 if (tb_port_read(up_port, &data, TB_CFG_PORT, cap, 1))
205 if (data & 0x80000000) {
206 tb_port_info(up_port,
207 "PCIe port already activated, aborting\n");
211 down_port = tb_find_unused_down_port(tb->root_switch);
213 tb_port_info(up_port,
214 "All PCIe down ports are occupied, aborting\n");
217 tunnel = tb_pci_alloc(tb, up_port, down_port);
219 tb_port_info(up_port,
220 "PCIe tunnel allocation failed, aborting\n");
224 if (tb_pci_activate(tunnel)) {
225 tb_port_info(up_port,
226 "PCIe tunnel activation failed, aborting\n");
231 list_add(&tunnel->list, &tcm->tunnel_list);
235 /* hotplug handling */
237 struct tb_hotplug_event {
238 struct work_struct work;
246 * tb_handle_hotplug() - handle hotplug event
248 * Executes on tb->wq.
250 static void tb_handle_hotplug(struct work_struct *work)
252 struct tb_hotplug_event *ev = container_of(work, typeof(*ev), work);
253 struct tb *tb = ev->tb;
254 struct tb_cm *tcm = tb_priv(tb);
255 struct tb_switch *sw;
256 struct tb_port *port;
257 mutex_lock(&tb->lock);
258 if (!tcm->hotplug_active)
259 goto out; /* during init, suspend or shutdown */
261 sw = tb_switch_find_by_route(tb, ev->route);
264 "hotplug event from non existent switch %llx:%x (unplug: %d)\n",
265 ev->route, ev->port, ev->unplug);
268 if (ev->port > sw->config.max_port_number) {
270 "hotplug event from non existent port %llx:%x (unplug: %d)\n",
271 ev->route, ev->port, ev->unplug);
274 port = &sw->ports[ev->port];
275 if (tb_is_upstream_port(port)) {
277 "hotplug event for upstream port %llx:%x (unplug: %d)\n",
278 ev->route, ev->port, ev->unplug);
283 tb_port_info(port, "unplugged\n");
284 tb_sw_set_unplugged(port->remote->sw);
285 tb_free_invalid_tunnels(tb);
286 tb_switch_remove(port->remote->sw);
290 "got unplug event for disconnected port, ignoring\n");
292 } else if (port->remote) {
294 "got plug event for connected port, ignoring\n");
296 tb_port_info(port, "hotplug: scanning\n");
299 tb_port_info(port, "hotplug: no switch found\n");
300 } else if (port->remote->sw->config.depth > 1) {
301 tb_sw_warn(port->remote->sw,
302 "hotplug: chaining not supported\n");
304 tb_sw_info(port->remote->sw,
305 "hotplug: activating pcie devices\n");
306 tb_activate_pcie_devices(tb);
313 mutex_unlock(&tb->lock);
318 * tb_schedule_hotplug_handler() - callback function for the control channel
320 * Delegates to tb_handle_hotplug.
322 static void tb_handle_event(struct tb *tb, enum tb_cfg_pkg_type type,
323 const void *buf, size_t size)
325 const struct cfg_event_pkg *pkg = buf;
326 struct tb_hotplug_event *ev;
329 if (type != TB_CFG_PKG_EVENT) {
330 tb_warn(tb, "unexpected event %#x, ignoring\n", type);
334 route = tb_cfg_get_route(&pkg->header);
336 if (tb_cfg_error(tb->ctl, route, pkg->port,
337 TB_CFG_ERROR_ACK_PLUG_EVENT)) {
338 tb_warn(tb, "could not ack plug event on %llx:%x\n", route,
342 ev = kmalloc(sizeof(*ev), GFP_KERNEL);
345 INIT_WORK(&ev->work, tb_handle_hotplug);
348 ev->port = pkg->port;
349 ev->unplug = pkg->unplug;
350 queue_work(tb->wq, &ev->work);
353 static void tb_stop(struct tb *tb)
355 struct tb_cm *tcm = tb_priv(tb);
356 struct tb_pci_tunnel *tunnel;
357 struct tb_pci_tunnel *n;
359 /* tunnels are only present after everything has been initialized */
360 list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
361 tb_pci_deactivate(tunnel);
364 tb_switch_remove(tb->root_switch);
365 tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */
368 static int tb_start(struct tb *tb)
370 struct tb_cm *tcm = tb_priv(tb);
373 tb->root_switch = tb_switch_alloc(tb, &tb->dev, 0);
374 if (!tb->root_switch)
378 * ICM firmware upgrade needs running firmware and in native
379 * mode that is not available so disable firmware upgrade of the
382 tb->root_switch->no_nvm_upgrade = true;
384 ret = tb_switch_configure(tb->root_switch);
386 tb_switch_put(tb->root_switch);
390 /* Announce the switch to the world */
391 ret = tb_switch_add(tb->root_switch);
393 tb_switch_put(tb->root_switch);
397 /* Full scan to discover devices added before the driver was loaded. */
398 tb_scan_switch(tb->root_switch);
399 tb_activate_pcie_devices(tb);
401 /* Allow tb_handle_hotplug to progress events */
402 tcm->hotplug_active = true;
406 static int tb_suspend_noirq(struct tb *tb)
408 struct tb_cm *tcm = tb_priv(tb);
410 tb_info(tb, "suspending...\n");
411 tb_switch_suspend(tb->root_switch);
412 tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */
413 tb_info(tb, "suspend finished\n");
418 static int tb_resume_noirq(struct tb *tb)
420 struct tb_cm *tcm = tb_priv(tb);
421 struct tb_pci_tunnel *tunnel, *n;
423 tb_info(tb, "resuming...\n");
425 /* remove any pci devices the firmware might have setup */
426 tb_switch_reset(tb, 0);
428 tb_switch_resume(tb->root_switch);
429 tb_free_invalid_tunnels(tb);
430 tb_free_unplugged_children(tb->root_switch);
431 list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list)
432 tb_pci_restart(tunnel);
433 if (!list_empty(&tcm->tunnel_list)) {
435 * the pcie links need some time to get going.
436 * 100ms works for me...
438 tb_info(tb, "tunnels restarted, sleeping for 100ms\n");
441 /* Allow tb_handle_hotplug to progress events */
442 tcm->hotplug_active = true;
443 tb_info(tb, "resume finished\n");
448 static const struct tb_cm_ops tb_cm_ops = {
451 .suspend_noirq = tb_suspend_noirq,
452 .resume_noirq = tb_resume_noirq,
453 .handle_event = tb_handle_event,
456 struct tb *tb_probe(struct tb_nhi *nhi)
461 if (!x86_apple_machine)
464 tb = tb_domain_alloc(nhi, sizeof(*tcm));
468 tb->security_level = TB_SECURITY_NONE;
469 tb->cm_ops = &tb_cm_ops;
472 INIT_LIST_HEAD(&tcm->tunnel_list);