diff options
Diffstat (limited to 'drivers/thunderbolt/tb.c')
| -rw-r--r-- | drivers/thunderbolt/tb.c | 1542 |
1 files changed, 1542 insertions, 0 deletions
diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c new file mode 100644 index 000000000..a56ea540a --- /dev/null +++ b/drivers/thunderbolt/tb.c @@ -0,0 +1,1542 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Thunderbolt driver - bus logic (NHI independent) + * + * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com> + * Copyright (C) 2019, Intel Corporation + */ + +#include <linux/slab.h> +#include <linux/errno.h> +#include <linux/delay.h> +#include <linux/pm_runtime.h> + +#include "tb.h" +#include "tb_regs.h" +#include "tunnel.h" + +/** + * struct tb_cm - Simple Thunderbolt connection manager + * @tunnel_list: List of active tunnels + * @dp_resources: List of available DP resources for DP tunneling + * @hotplug_active: tb_handle_hotplug will stop progressing plug + * events and exit if this is not set (it needs to + * acquire the lock one more time). Used to drain wq + * after cfg has been paused. + * @remove_work: Work used to remove any unplugged routers after + * runtime resume + */ +struct tb_cm { + struct list_head tunnel_list; + struct list_head dp_resources; + bool hotplug_active; + struct delayed_work remove_work; +}; + +static inline struct tb *tcm_to_tb(struct tb_cm *tcm) +{ + return ((void *)tcm - sizeof(struct tb)); +} + +struct tb_hotplug_event { + struct work_struct work; + struct tb *tb; + u64 route; + u8 port; + bool unplug; +}; + +static void tb_handle_hotplug(struct work_struct *work); + +static void tb_queue_hotplug(struct tb *tb, u64 route, u8 port, bool unplug) +{ + struct tb_hotplug_event *ev; + + ev = kmalloc(sizeof(*ev), GFP_KERNEL); + if (!ev) + return; + + ev->tb = tb; + ev->route = route; + ev->port = port; + ev->unplug = unplug; + INIT_WORK(&ev->work, tb_handle_hotplug); + queue_work(tb->wq, &ev->work); +} + +/* enumeration & hot plug handling */ + +static void tb_add_dp_resources(struct tb_switch *sw) +{ + struct tb_cm *tcm = tb_priv(sw->tb); + struct tb_port *port; + + tb_switch_for_each_port(sw, port) { + if (!tb_port_is_dpin(port)) + continue; + + if (!tb_switch_query_dp_resource(sw, port)) + continue; + + list_add_tail(&port->list, &tcm->dp_resources); + tb_port_dbg(port, "DP IN resource available\n"); + } +} + +static void tb_remove_dp_resources(struct tb_switch *sw) +{ + struct tb_cm *tcm = tb_priv(sw->tb); + struct tb_port *port, *tmp; + + /* Clear children resources first */ + tb_switch_for_each_port(sw, port) { + if (tb_port_has_remote(port)) + tb_remove_dp_resources(port->remote->sw); + } + + list_for_each_entry_safe(port, tmp, &tcm->dp_resources, list) { + if (port->sw == sw) { + tb_port_dbg(port, "DP OUT resource unavailable\n"); + list_del_init(&port->list); + } + } +} + +static void tb_discover_tunnels(struct tb_switch *sw) +{ + struct tb *tb = sw->tb; + struct tb_cm *tcm = tb_priv(tb); + struct tb_port *port; + + tb_switch_for_each_port(sw, port) { + struct tb_tunnel *tunnel = NULL; + + switch (port->config.type) { + case TB_TYPE_DP_HDMI_IN: + tunnel = tb_tunnel_discover_dp(tb, port); + break; + + case TB_TYPE_PCIE_DOWN: + tunnel = tb_tunnel_discover_pci(tb, port); + break; + + case TB_TYPE_USB3_DOWN: + tunnel = tb_tunnel_discover_usb3(tb, port); + break; + + default: + break; + } + + if (!tunnel) + continue; + + if (tb_tunnel_is_pci(tunnel)) { + struct tb_switch *parent = tunnel->dst_port->sw; + + while (parent != tunnel->src_port->sw) { + parent->boot = true; + parent = tb_switch_parent(parent); + } + } else if (tb_tunnel_is_dp(tunnel)) { + /* Keep the domain from powering down */ + pm_runtime_get_sync(&tunnel->src_port->sw->dev); + pm_runtime_get_sync(&tunnel->dst_port->sw->dev); + } + + list_add_tail(&tunnel->list, &tcm->tunnel_list); + } + + tb_switch_for_each_port(sw, port) { + if (tb_port_has_remote(port)) + tb_discover_tunnels(port->remote->sw); + } +} + +static int tb_port_configure_xdomain(struct tb_port *port) +{ + /* + * XDomain paths currently only support single lane so we must + * disable the other lane according to USB4 spec. + */ + tb_port_disable(port->dual_link_port); + + if (tb_switch_is_usb4(port->sw)) + return usb4_port_configure_xdomain(port); + return tb_lc_configure_xdomain(port); +} + +static void tb_port_unconfigure_xdomain(struct tb_port *port) +{ + if (tb_switch_is_usb4(port->sw)) + usb4_port_unconfigure_xdomain(port); + else + tb_lc_unconfigure_xdomain(port); + + tb_port_enable(port->dual_link_port); +} + +static void tb_scan_xdomain(struct tb_port *port) +{ + struct tb_switch *sw = port->sw; + struct tb *tb = sw->tb; + struct tb_xdomain *xd; + u64 route; + + route = tb_downstream_route(port); + xd = tb_xdomain_find_by_route(tb, route); + if (xd) { + tb_xdomain_put(xd); + return; + } + + xd = tb_xdomain_alloc(tb, &sw->dev, route, tb->root_switch->uuid, + NULL); + if (xd) { + tb_port_at(route, sw)->xdomain = xd; + tb_port_configure_xdomain(port); + tb_xdomain_add(xd); + } +} + +static int tb_enable_tmu(struct tb_switch *sw) +{ + int ret; + + /* If it is already enabled in correct mode, don't touch it */ + if (tb_switch_tmu_is_enabled(sw)) + return 0; + + ret = tb_switch_tmu_disable(sw); + if (ret) + return ret; + + ret = tb_switch_tmu_post_time(sw); + if (ret) + return ret; + + return tb_switch_tmu_enable(sw); +} + +/** + * tb_find_unused_port() - return the first inactive port on @sw + * @sw: Switch to find the port on + * @type: Port type to look for + */ +static struct tb_port *tb_find_unused_port(struct tb_switch *sw, + enum tb_port_type type) +{ + struct tb_port *port; + + tb_switch_for_each_port(sw, port) { + if (tb_is_upstream_port(port)) + continue; + if (port->config.type != type) + continue; + if (!port->cap_adap) + continue; + if (tb_port_is_enabled(port)) + continue; + return port; + } + return NULL; +} + +static struct tb_port *tb_find_usb3_down(struct tb_switch *sw, + const struct tb_port *port) +{ + struct tb_port *down; + + down = usb4_switch_map_usb3_down(sw, port); + if (down && !tb_usb3_port_is_enabled(down)) + return down; + return NULL; +} + +static struct tb_tunnel *tb_find_tunnel(struct tb *tb, enum tb_tunnel_type type, + struct tb_port *src_port, + struct tb_port *dst_port) +{ + struct tb_cm *tcm = tb_priv(tb); + struct tb_tunnel *tunnel; + + list_for_each_entry(tunnel, &tcm->tunnel_list, list) { + if (tunnel->type == type && + ((src_port && src_port == tunnel->src_port) || + (dst_port && dst_port == tunnel->dst_port))) { + return tunnel; + } + } + + return NULL; +} + +static struct tb_tunnel *tb_find_first_usb3_tunnel(struct tb *tb, + struct tb_port *src_port, + struct tb_port *dst_port) +{ + struct tb_port *port, *usb3_down; + struct tb_switch *sw; + + /* Pick the router that is deepest in the topology */ + if (dst_port->sw->config.depth > src_port->sw->config.depth) + sw = dst_port->sw; + else + sw = src_port->sw; + + /* Can't be the host router */ + if (sw == tb->root_switch) + return NULL; + + /* Find the downstream USB4 port that leads to this router */ + port = tb_port_at(tb_route(sw), tb->root_switch); + /* Find the corresponding host router USB3 downstream port */ + usb3_down = usb4_switch_map_usb3_down(tb->root_switch, port); + if (!usb3_down) + return NULL; + + return tb_find_tunnel(tb, TB_TUNNEL_USB3, usb3_down, NULL); +} + +static int tb_available_bandwidth(struct tb *tb, struct tb_port *src_port, + struct tb_port *dst_port, int *available_up, int *available_down) +{ + int usb3_consumed_up, usb3_consumed_down, ret; + struct tb_cm *tcm = tb_priv(tb); + struct tb_tunnel *tunnel; + struct tb_port *port; + + tb_port_dbg(dst_port, "calculating available bandwidth\n"); + + tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port); + if (tunnel) { + ret = tb_tunnel_consumed_bandwidth(tunnel, &usb3_consumed_up, + &usb3_consumed_down); + if (ret) + return ret; + } else { + usb3_consumed_up = 0; + usb3_consumed_down = 0; + } + + *available_up = *available_down = 40000; + + /* Find the minimum available bandwidth over all links */ + tb_for_each_port_on_path(src_port, dst_port, port) { + int link_speed, link_width, up_bw, down_bw; + + if (!tb_port_is_null(port)) + continue; + + if (tb_is_upstream_port(port)) { + link_speed = port->sw->link_speed; + } else { + link_speed = tb_port_get_link_speed(port); + if (link_speed < 0) + return link_speed; + } + + link_width = port->bonded ? 2 : 1; + + up_bw = link_speed * link_width * 1000; /* Mb/s */ + /* Leave 10% guard band */ + up_bw -= up_bw / 10; + down_bw = up_bw; + + tb_port_dbg(port, "link total bandwidth %d Mb/s\n", up_bw); + + /* + * Find all DP tunnels that cross the port and reduce + * their consumed bandwidth from the available. + */ + list_for_each_entry(tunnel, &tcm->tunnel_list, list) { + int dp_consumed_up, dp_consumed_down; + + if (!tb_tunnel_is_dp(tunnel)) + continue; + + if (!tb_tunnel_port_on_path(tunnel, port)) + continue; + + ret = tb_tunnel_consumed_bandwidth(tunnel, + &dp_consumed_up, + &dp_consumed_down); + if (ret) + return ret; + + up_bw -= dp_consumed_up; + down_bw -= dp_consumed_down; + } + + /* + * If USB3 is tunneled from the host router down to the + * branch leading to port we need to take USB3 consumed + * bandwidth into account regardless whether it actually + * crosses the port. + */ + up_bw -= usb3_consumed_up; + down_bw -= usb3_consumed_down; + + if (up_bw < *available_up) + *available_up = up_bw; + if (down_bw < *available_down) + *available_down = down_bw; + } + + if (*available_up < 0) + *available_up = 0; + if (*available_down < 0) + *available_down = 0; + + return 0; +} + +static int tb_release_unused_usb3_bandwidth(struct tb *tb, + struct tb_port *src_port, + struct tb_port *dst_port) +{ + struct tb_tunnel *tunnel; + + tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port); + return tunnel ? tb_tunnel_release_unused_bandwidth(tunnel) : 0; +} + +static void tb_reclaim_usb3_bandwidth(struct tb *tb, struct tb_port *src_port, + struct tb_port *dst_port) +{ + int ret, available_up, available_down; + struct tb_tunnel *tunnel; + + tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port); + if (!tunnel) + return; + + tb_dbg(tb, "reclaiming unused bandwidth for USB3\n"); + + /* + * Calculate available bandwidth for the first hop USB3 tunnel. + * That determines the whole USB3 bandwidth for this branch. + */ + ret = tb_available_bandwidth(tb, tunnel->src_port, tunnel->dst_port, + &available_up, &available_down); + if (ret) { + tb_warn(tb, "failed to calculate available bandwidth\n"); + return; + } + + tb_dbg(tb, "available bandwidth for USB3 %d/%d Mb/s\n", + available_up, available_down); + + tb_tunnel_reclaim_available_bandwidth(tunnel, &available_up, &available_down); +} + +static int tb_tunnel_usb3(struct tb *tb, struct tb_switch *sw) +{ + struct tb_switch *parent = tb_switch_parent(sw); + int ret, available_up, available_down; + struct tb_port *up, *down, *port; + struct tb_cm *tcm = tb_priv(tb); + struct tb_tunnel *tunnel; + + up = tb_switch_find_port(sw, TB_TYPE_USB3_UP); + if (!up) + return 0; + + if (!sw->link_usb4) + return 0; + + /* + * Look up available down port. Since we are chaining it should + * be found right above this switch. + */ + port = tb_port_at(tb_route(sw), parent); + down = tb_find_usb3_down(parent, port); + if (!down) + return 0; + + if (tb_route(parent)) { + struct tb_port *parent_up; + /* + * Check first that the parent switch has its upstream USB3 + * port enabled. Otherwise the chain is not complete and + * there is no point setting up a new tunnel. + */ + parent_up = tb_switch_find_port(parent, TB_TYPE_USB3_UP); + if (!parent_up || !tb_port_is_enabled(parent_up)) + return 0; + + /* Make all unused bandwidth available for the new tunnel */ + ret = tb_release_unused_usb3_bandwidth(tb, down, up); + if (ret) + return ret; + } + + ret = tb_available_bandwidth(tb, down, up, &available_up, + &available_down); + if (ret) + goto err_reclaim; + + tb_port_dbg(up, "available bandwidth for new USB3 tunnel %d/%d Mb/s\n", + available_up, available_down); + + tunnel = tb_tunnel_alloc_usb3(tb, up, down, available_up, + available_down); + if (!tunnel) { + ret = -ENOMEM; + goto err_reclaim; + } + + if (tb_tunnel_activate(tunnel)) { + tb_port_info(up, + "USB3 tunnel activation failed, aborting\n"); + ret = -EIO; + goto err_free; + } + + list_add_tail(&tunnel->list, &tcm->tunnel_list); + if (tb_route(parent)) + tb_reclaim_usb3_bandwidth(tb, down, up); + + return 0; + +err_free: + tb_tunnel_free(tunnel); +err_reclaim: + if (tb_route(parent)) + tb_reclaim_usb3_bandwidth(tb, down, up); + + return ret; +} + +static int tb_create_usb3_tunnels(struct tb_switch *sw) +{ + struct tb_port *port; + int ret; + + if (tb_route(sw)) { + ret = tb_tunnel_usb3(sw->tb, sw); + if (ret) + return ret; + } + + tb_switch_for_each_port(sw, port) { + if (!tb_port_has_remote(port)) + continue; + ret = tb_create_usb3_tunnels(port->remote->sw); + if (ret) + return ret; + } + + return 0; +} + +static void tb_scan_port(struct tb_port *port); + +/** + * tb_scan_switch() - scan for and initialize downstream switches + */ +static void tb_scan_switch(struct tb_switch *sw) +{ + struct tb_port *port; + + pm_runtime_get_sync(&sw->dev); + + tb_switch_for_each_port(sw, port) + tb_scan_port(port); + + pm_runtime_mark_last_busy(&sw->dev); + pm_runtime_put_autosuspend(&sw->dev); +} + +/** + * tb_scan_port() - check for and initialize switches below port + */ +static void tb_scan_port(struct tb_port *port) +{ + struct tb_cm *tcm = tb_priv(port->sw->tb); + struct tb_port *upstream_port; + struct tb_switch *sw; + + if (tb_is_upstream_port(port)) + return; + + if (tb_port_is_dpout(port) && tb_dp_port_hpd_is_active(port) == 1 && + !tb_dp_port_is_enabled(port)) { + tb_port_dbg(port, "DP adapter HPD set, queuing hotplug\n"); + tb_queue_hotplug(port->sw->tb, tb_route(port->sw), port->port, + false); + return; + } + + if (port->config.type != TB_TYPE_PORT) + return; + if (port->dual_link_port && port->link_nr) + return; /* + * Downstream switch is reachable through two ports. + * Only scan on the primary port (link_nr == 0). + */ + if (tb_wait_for_port(port, false) <= 0) + return; + if (port->remote) { + tb_port_dbg(port, "port already has a remote\n"); + return; + } + + tb_retimer_scan(port); + + sw = tb_switch_alloc(port->sw->tb, &port->sw->dev, + tb_downstream_route(port)); + if (IS_ERR(sw)) { + /* + * If there is an error accessing the connected switch + * it may be connected to another domain. Also we allow + * the other domain to be connected to a max depth switch. + */ + if (PTR_ERR(sw) == -EIO || PTR_ERR(sw) == -EADDRNOTAVAIL) + tb_scan_xdomain(port); + return; + } + + if (tb_switch_configure(sw)) { + tb_switch_put(sw); + return; + } + + /* + * If there was previously another domain connected remove it + * first. + */ + if (port->xdomain) { + tb_xdomain_remove(port->xdomain); + tb_port_unconfigure_xdomain(port); + port->xdomain = NULL; + } + + /* + * Do not send uevents until we have discovered all existing + * tunnels and know which switches were authorized already by + * the boot firmware. + */ + if (!tcm->hotplug_active) + dev_set_uevent_suppress(&sw->dev, true); + + /* + * At the moment Thunderbolt 2 and beyond (devices with LC) we + * can support runtime PM. + */ + sw->rpm = sw->generation > 1; + + if (tb_switch_add(sw)) { + tb_switch_put(sw); + return; + } + + /* Link the switches using both links if available */ + upstream_port = tb_upstream_port(sw); + port->remote = upstream_port; + upstream_port->remote = port; + if (port->dual_link_port && upstream_port->dual_link_port) { + port->dual_link_port->remote = upstream_port->dual_link_port; + upstream_port->dual_link_port->remote = port->dual_link_port; + } + + /* Enable lane bonding if supported */ + tb_switch_lane_bonding_enable(sw); + /* Set the link configured */ + tb_switch_configure_link(sw); + + if (tb_enable_tmu(sw)) + tb_sw_warn(sw, "failed to enable TMU\n"); + + /* Scan upstream retimers */ + tb_retimer_scan(upstream_port); + + /* + * Create USB 3.x tunnels only when the switch is plugged to the + * domain. This is because we scan the domain also during discovery + * and want to discover existing USB 3.x tunnels before we create + * any new. + */ + if (tcm->hotplug_active && tb_tunnel_usb3(sw->tb, sw)) + tb_sw_warn(sw, "USB3 tunnel creation failed\n"); + + tb_add_dp_resources(sw); + tb_scan_switch(sw); +} + +static void tb_deactivate_and_free_tunnel(struct tb_tunnel *tunnel) +{ + struct tb_port *src_port, *dst_port; + struct tb *tb; + + if (!tunnel) + return; + + tb_tunnel_deactivate(tunnel); + list_del(&tunnel->list); + + tb = tunnel->tb; + src_port = tunnel->src_port; + dst_port = tunnel->dst_port; + + switch (tunnel->type) { + case TB_TUNNEL_DP: + /* + * In case of DP tunnel make sure the DP IN resource is + * deallocated properly. + */ + tb_switch_dealloc_dp_resource(src_port->sw, src_port); + /* Now we can allow the domain to runtime suspend again */ + pm_runtime_mark_last_busy(&dst_port->sw->dev); + pm_runtime_put_autosuspend(&dst_port->sw->dev); + pm_runtime_mark_last_busy(&src_port->sw->dev); + pm_runtime_put_autosuspend(&src_port->sw->dev); + fallthrough; + + case TB_TUNNEL_USB3: + tb_reclaim_usb3_bandwidth(tb, src_port, dst_port); + break; + + default: + /* + * PCIe and DMA tunnels do not consume guaranteed + * bandwidth. + */ + break; + } + + tb_tunnel_free(tunnel); +} + +/** + * tb_free_invalid_tunnels() - destroy tunnels of devices that have gone away + */ +static void tb_free_invalid_tunnels(struct tb *tb) +{ + struct tb_cm *tcm = tb_priv(tb); + struct tb_tunnel *tunnel; + struct tb_tunnel *n; + + list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) { + if (tb_tunnel_is_invalid(tunnel)) + tb_deactivate_and_free_tunnel(tunnel); + } +} + +/** + * tb_free_unplugged_children() - traverse hierarchy and free unplugged switches + */ +static void tb_free_unplugged_children(struct tb_switch *sw) +{ + struct tb_port *port; + + tb_switch_for_each_port(sw, port) { + if (!tb_port_has_remote(port)) + continue; + + if (port->remote->sw->is_unplugged) { + tb_retimer_remove_all(port); + tb_remove_dp_resources(port->remote->sw); + tb_switch_unconfigure_link(port->remote->sw); + tb_switch_lane_bonding_disable(port->remote->sw); + tb_switch_remove(port->remote->sw); + port->remote = NULL; + if (port->dual_link_port) + port->dual_link_port->remote = NULL; + } else { + tb_free_unplugged_children(port->remote->sw); + } + } +} + +static struct tb_port *tb_find_pcie_down(struct tb_switch *sw, + const struct tb_port *port) +{ + struct tb_port *down = NULL; + + /* + * To keep plugging devices consistently in the same PCIe + * hierarchy, do mapping here for switch downstream PCIe ports. + */ + if (tb_switch_is_usb4(sw)) { + down = usb4_switch_map_pcie_down(sw, port); + } else if (!tb_route(sw)) { + int phy_port = tb_phy_port_from_link(port->port); + int index; + + /* + * Hard-coded Thunderbolt port to PCIe down port mapping + * per controller. + */ + if (tb_switch_is_cactus_ridge(sw) || + tb_switch_is_alpine_ridge(sw)) + index = !phy_port ? 6 : 7; + else if (tb_switch_is_falcon_ridge(sw)) + index = !phy_port ? 6 : 8; + else if (tb_switch_is_titan_ridge(sw)) + index = !phy_port ? 8 : 9; + else + goto out; + + /* Validate the hard-coding */ + if (WARN_ON(index > sw->config.max_port_number)) + goto out; + + down = &sw->ports[index]; + } + + if (down) { + if (WARN_ON(!tb_port_is_pcie_down(down))) + goto out; + if (tb_pci_port_is_enabled(down)) + goto out; + + return down; + } + +out: + return tb_find_unused_port(sw, TB_TYPE_PCIE_DOWN); +} + +static struct tb_port *tb_find_dp_out(struct tb *tb, struct tb_port *in) +{ + struct tb_port *host_port, *port; + struct tb_cm *tcm = tb_priv(tb); + + host_port = tb_route(in->sw) ? + tb_port_at(tb_route(in->sw), tb->root_switch) : NULL; + + list_for_each_entry(port, &tcm->dp_resources, list) { + if (!tb_port_is_dpout(port)) + continue; + + if (tb_port_is_enabled(port)) { + tb_port_dbg(port, "in use\n"); + continue; + } + + tb_port_dbg(port, "DP OUT available\n"); + + /* + * Keep the DP tunnel under the topology starting from + * the same host router downstream port. + */ + if (host_port && tb_route(port->sw)) { + struct tb_port *p; + + p = tb_port_at(tb_route(port->sw), tb->root_switch); + if (p != host_port) + continue; + } + + return port; + } + + return NULL; +} + +static void tb_tunnel_dp(struct tb *tb) +{ + int available_up, available_down, ret; + struct tb_cm *tcm = tb_priv(tb); + struct tb_port *port, *in, *out; + struct tb_tunnel *tunnel; + + /* + * Find pair of inactive DP IN and DP OUT adapters and then + * establish a DP tunnel between them. + */ + tb_dbg(tb, "looking for DP IN <-> DP OUT pairs:\n"); + + in = NULL; + out = NULL; + list_for_each_entry(port, &tcm->dp_resources, list) { + if (!tb_port_is_dpin(port)) + continue; + + if (tb_port_is_enabled(port)) { + tb_port_dbg(port, "in use\n"); + continue; + } + + tb_port_dbg(port, "DP IN available\n"); + + out = tb_find_dp_out(tb, port); + if (out) { + in = port; + break; + } + } + + if (!in) { + tb_dbg(tb, "no suitable DP IN adapter available, not tunneling\n"); + return; + } + if (!out) { + tb_dbg(tb, "no suitable DP OUT adapter available, not tunneling\n"); + return; + } + + /* + * DP stream needs the domain to be active so runtime resume + * both ends of the tunnel. + * + * This should bring the routers in the middle active as well + * and keeps the domain from runtime suspending while the DP + * tunnel is active. + */ + pm_runtime_get_sync(&in->sw->dev); + pm_runtime_get_sync(&out->sw->dev); + + if (tb_switch_alloc_dp_resource(in->sw, in)) { + tb_port_dbg(in, "no resource available for DP IN, not tunneling\n"); + goto err_rpm_put; + } + + /* Make all unused USB3 bandwidth available for the new DP tunnel */ + ret = tb_release_unused_usb3_bandwidth(tb, in, out); + if (ret) { + tb_warn(tb, "failed to release unused bandwidth\n"); + goto err_dealloc_dp; + } + + ret = tb_available_bandwidth(tb, in, out, &available_up, + &available_down); + if (ret) + goto err_reclaim; + + tb_dbg(tb, "available bandwidth for new DP tunnel %u/%u Mb/s\n", + available_up, available_down); + + tunnel = tb_tunnel_alloc_dp(tb, in, out, available_up, available_down); + if (!tunnel) { + tb_port_dbg(out, "could not allocate DP tunnel\n"); + goto err_reclaim; + } + + if (tb_tunnel_activate(tunnel)) { + tb_port_info(out, "DP tunnel activation failed, aborting\n"); + goto err_free; + } + + list_add_tail(&tunnel->list, &tcm->tunnel_list); + tb_reclaim_usb3_bandwidth(tb, in, out); + return; + +err_free: + tb_tunnel_free(tunnel); +err_reclaim: + tb_reclaim_usb3_bandwidth(tb, in, out); +err_dealloc_dp: + tb_switch_dealloc_dp_resource(in->sw, in); +err_rpm_put: + pm_runtime_mark_last_busy(&out->sw->dev); + pm_runtime_put_autosuspend(&out->sw->dev); + pm_runtime_mark_last_busy(&in->sw->dev); + pm_runtime_put_autosuspend(&in->sw->dev); +} + +static void tb_dp_resource_unavailable(struct tb *tb, struct tb_port *port) +{ + struct tb_port *in, *out; + struct tb_tunnel *tunnel; + + if (tb_port_is_dpin(port)) { + tb_port_dbg(port, "DP IN resource unavailable\n"); + in = port; + out = NULL; + } else { + tb_port_dbg(port, "DP OUT resource unavailable\n"); + in = NULL; + out = port; + } + + tunnel = tb_find_tunnel(tb, TB_TUNNEL_DP, in, out); + tb_deactivate_and_free_tunnel(tunnel); + list_del_init(&port->list); + + /* + * See if there is another DP OUT port that can be used for + * to create another tunnel. + */ + tb_tunnel_dp(tb); +} + +static void tb_dp_resource_available(struct tb *tb, struct tb_port *port) +{ + struct tb_cm *tcm = tb_priv(tb); + struct tb_port *p; + + if (tb_port_is_enabled(port)) + return; + + list_for_each_entry(p, &tcm->dp_resources, list) { + if (p == port) + return; + } + + tb_port_dbg(port, "DP %s resource available\n", + tb_port_is_dpin(port) ? "IN" : "OUT"); + list_add_tail(&port->list, &tcm->dp_resources); + + /* Look for suitable DP IN <-> DP OUT pairs now */ + tb_tunnel_dp(tb); +} + +static void tb_disconnect_and_release_dp(struct tb *tb) +{ + struct tb_cm *tcm = tb_priv(tb); + struct tb_tunnel *tunnel, *n; + + /* + * Tear down all DP tunnels and release their resources. They + * will be re-established after resume based on plug events. + */ + list_for_each_entry_safe_reverse(tunnel, n, &tcm->tunnel_list, list) { + if (tb_tunnel_is_dp(tunnel)) + tb_deactivate_and_free_tunnel(tunnel); + } + + while (!list_empty(&tcm->dp_resources)) { + struct tb_port *port; + + port = list_first_entry(&tcm->dp_resources, + struct tb_port, list); + list_del_init(&port->list); + } +} + +static int tb_tunnel_pci(struct tb *tb, struct tb_switch *sw) +{ + struct tb_port *up, *down, *port; + struct tb_cm *tcm = tb_priv(tb); + struct tb_switch *parent_sw; + struct tb_tunnel *tunnel; + + up = tb_switch_find_port(sw, TB_TYPE_PCIE_UP); + if (!up) + return 0; + + /* + * Look up available down port. Since we are chaining it should + * be found right above this switch. + */ + parent_sw = tb_to_switch(sw->dev.parent); + port = tb_port_at(tb_route(sw), parent_sw); + down = tb_find_pcie_down(parent_sw, port); + if (!down) + return 0; + + tunnel = tb_tunnel_alloc_pci(tb, up, down); + if (!tunnel) + return -ENOMEM; + + if (tb_tunnel_activate(tunnel)) { + tb_port_info(up, + "PCIe tunnel activation failed, aborting\n"); + tb_tunnel_free(tunnel); + return -EIO; + } + + list_add_tail(&tunnel->list, &tcm->tunnel_list); + return 0; +} + +static int tb_approve_xdomain_paths(struct tb *tb, struct tb_xdomain *xd) +{ + struct tb_cm *tcm = tb_priv(tb); + struct tb_port *nhi_port, *dst_port; + struct tb_tunnel *tunnel; + struct tb_switch *sw; + + sw = tb_to_switch(xd->dev.parent); + dst_port = tb_port_at(xd->route, sw); + nhi_port = tb_switch_find_port(tb->root_switch, TB_TYPE_NHI); + + mutex_lock(&tb->lock); + tunnel = tb_tunnel_alloc_dma(tb, nhi_port, dst_port, xd->transmit_ring, + xd->transmit_path, xd->receive_ring, + xd->receive_path); + if (!tunnel) { + mutex_unlock(&tb->lock); + return -ENOMEM; + } + + if (tb_tunnel_activate(tunnel)) { + tb_port_info(nhi_port, + "DMA tunnel activation failed, aborting\n"); + tb_tunnel_free(tunnel); + mutex_unlock(&tb->lock); + return -EIO; + } + + list_add_tail(&tunnel->list, &tcm->tunnel_list); + mutex_unlock(&tb->lock); + return 0; +} + +static void __tb_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd) +{ + struct tb_port *dst_port; + struct tb_tunnel *tunnel; + struct tb_switch *sw; + + sw = tb_to_switch(xd->dev.parent); + dst_port = tb_port_at(xd->route, sw); + + /* + * It is possible that the tunnel was already teared down (in + * case of cable disconnect) so it is fine if we cannot find it + * here anymore. + */ + tunnel = tb_find_tunnel(tb, TB_TUNNEL_DMA, NULL, dst_port); + tb_deactivate_and_free_tunnel(tunnel); +} + +static int tb_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd) +{ + if (!xd->is_unplugged) { + mutex_lock(&tb->lock); + __tb_disconnect_xdomain_paths(tb, xd); + mutex_unlock(&tb->lock); + } + return 0; +} + +/* hotplug handling */ + +/** + * tb_handle_hotplug() - handle hotplug event + * + * Executes on tb->wq. + */ +static void tb_handle_hotplug(struct work_struct *work) +{ + struct tb_hotplug_event *ev = container_of(work, typeof(*ev), work); + struct tb *tb = ev->tb; + struct tb_cm *tcm = tb_priv(tb); + struct tb_switch *sw; + struct tb_port *port; + + /* Bring the domain back from sleep if it was suspended */ + pm_runtime_get_sync(&tb->dev); + + mutex_lock(&tb->lock); + if (!tcm->hotplug_active) + goto out; /* during init, suspend or shutdown */ + + sw = tb_switch_find_by_route(tb, ev->route); + if (!sw) { + tb_warn(tb, + "hotplug event from non existent switch %llx:%x (unplug: %d)\n", + ev->route, ev->port, ev->unplug); + goto out; + } + if (ev->port > sw->config.max_port_number) { + tb_warn(tb, + "hotplug event from non existent port %llx:%x (unplug: %d)\n", + ev->route, ev->port, ev->unplug); + goto put_sw; + } + port = &sw->ports[ev->port]; + if (tb_is_upstream_port(port)) { + tb_dbg(tb, "hotplug event for upstream port %llx:%x (unplug: %d)\n", + ev->route, ev->port, ev->unplug); + goto put_sw; + } + + pm_runtime_get_sync(&sw->dev); + + if (ev->unplug) { + tb_retimer_remove_all(port); + + if (tb_port_has_remote(port)) { + tb_port_dbg(port, "switch unplugged\n"); + tb_sw_set_unplugged(port->remote->sw); + tb_free_invalid_tunnels(tb); + tb_remove_dp_resources(port->remote->sw); + tb_switch_tmu_disable(port->remote->sw); + tb_switch_unconfigure_link(port->remote->sw); + tb_switch_lane_bonding_disable(port->remote->sw); + tb_switch_remove(port->remote->sw); + port->remote = NULL; + if (port->dual_link_port) + port->dual_link_port->remote = NULL; + /* Maybe we can create another DP tunnel */ + tb_tunnel_dp(tb); + } else if (port->xdomain) { + struct tb_xdomain *xd = tb_xdomain_get(port->xdomain); + + tb_port_dbg(port, "xdomain unplugged\n"); + /* + * Service drivers are unbound during + * tb_xdomain_remove() so setting XDomain as + * unplugged here prevents deadlock if they call + * tb_xdomain_disable_paths(). We will tear down + * the path below. + */ + xd->is_unplugged = true; + tb_xdomain_remove(xd); + port->xdomain = NULL; + __tb_disconnect_xdomain_paths(tb, xd); + tb_xdomain_put(xd); + tb_port_unconfigure_xdomain(port); + } else if (tb_port_is_dpout(port) || tb_port_is_dpin(port)) { + tb_dp_resource_unavailable(tb, port); + } else { + tb_port_dbg(port, + "got unplug event for disconnected port, ignoring\n"); + } + } else if (port->remote) { + tb_port_dbg(port, "got plug event for connected port, ignoring\n"); + } else { + if (tb_port_is_null(port)) { + tb_port_dbg(port, "hotplug: scanning\n"); + tb_scan_port(port); + if (!port->remote) + tb_port_dbg(port, "hotplug: no switch found\n"); + } else if (tb_port_is_dpout(port) || tb_port_is_dpin(port)) { + tb_dp_resource_available(tb, port); + } + } + + pm_runtime_mark_last_busy(&sw->dev); + pm_runtime_put_autosuspend(&sw->dev); + +put_sw: + tb_switch_put(sw); +out: + mutex_unlock(&tb->lock); + + pm_runtime_mark_last_busy(&tb->dev); + pm_runtime_put_autosuspend(&tb->dev); + + kfree(ev); +} + +/** + * tb_schedule_hotplug_handler() - callback function for the control channel + * + * Delegates to tb_handle_hotplug. + */ +static void tb_handle_event(struct tb *tb, enum tb_cfg_pkg_type type, + const void *buf, size_t size) +{ + const struct cfg_event_pkg *pkg = buf; + u64 route; + + if (type != TB_CFG_PKG_EVENT) { + tb_warn(tb, "unexpected event %#x, ignoring\n", type); + return; + } + + route = tb_cfg_get_route(&pkg->header); + + if (tb_cfg_ack_plug(tb->ctl, route, pkg->port, pkg->unplug)) { + tb_warn(tb, "could not ack plug event on %llx:%x\n", route, + pkg->port); + } + + tb_queue_hotplug(tb, route, pkg->port, pkg->unplug); +} + +static void tb_stop(struct tb *tb) +{ + struct tb_cm *tcm = tb_priv(tb); + struct tb_tunnel *tunnel; + struct tb_tunnel *n; + + cancel_delayed_work(&tcm->remove_work); + /* tunnels are only present after everything has been initialized */ + list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) { + /* + * DMA tunnels require the driver to be functional so we + * tear them down. Other protocol tunnels can be left + * intact. + */ + if (tb_tunnel_is_dma(tunnel)) + tb_tunnel_deactivate(tunnel); + tb_tunnel_free(tunnel); + } + tb_switch_remove(tb->root_switch); + tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */ +} + +static int tb_scan_finalize_switch(struct device *dev, void *data) +{ + if (tb_is_switch(dev)) { + struct tb_switch *sw = tb_to_switch(dev); + + /* + * If we found that the switch was already setup by the + * boot firmware, mark it as authorized now before we + * send uevent to userspace. + */ + if (sw->boot) + sw->authorized = 1; + + dev_set_uevent_suppress(dev, false); + kobject_uevent(&dev->kobj, KOBJ_ADD); + device_for_each_child(dev, NULL, tb_scan_finalize_switch); + } + + return 0; +} + +static int tb_start(struct tb *tb) +{ + struct tb_cm *tcm = tb_priv(tb); + int ret; + + tb->root_switch = tb_switch_alloc(tb, &tb->dev, 0); + if (IS_ERR(tb->root_switch)) + return PTR_ERR(tb->root_switch); + + /* + * ICM firmware upgrade needs running firmware and in native + * mode that is not available so disable firmware upgrade of the + * root switch. + */ + tb->root_switch->no_nvm_upgrade = true; + /* All USB4 routers support runtime PM */ + tb->root_switch->rpm = tb_switch_is_usb4(tb->root_switch); + + ret = tb_switch_configure(tb->root_switch); + if (ret) { + tb_switch_put(tb->root_switch); + return ret; + } + + /* Announce the switch to the world */ + ret = tb_switch_add(tb->root_switch); + if (ret) { + tb_switch_put(tb->root_switch); + return ret; + } + + /* Enable TMU if it is off */ + tb_switch_tmu_enable(tb->root_switch); + /* Full scan to discover devices added before the driver was loaded. */ + tb_scan_switch(tb->root_switch); + /* Find out tunnels created by the boot firmware */ + tb_discover_tunnels(tb->root_switch); + /* + * If the boot firmware did not create USB 3.x tunnels create them + * now for the whole topology. + */ + tb_create_usb3_tunnels(tb->root_switch); + /* Add DP IN resources for the root switch */ + tb_add_dp_resources(tb->root_switch); + /* Make the discovered switches available to the userspace */ + device_for_each_child(&tb->root_switch->dev, NULL, + tb_scan_finalize_switch); + + /* Allow tb_handle_hotplug to progress events */ + tcm->hotplug_active = true; + return 0; +} + +static int tb_suspend_noirq(struct tb *tb) +{ + struct tb_cm *tcm = tb_priv(tb); + + tb_dbg(tb, "suspending...\n"); + tb_disconnect_and_release_dp(tb); + tb_switch_suspend(tb->root_switch, false); + tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */ + tb_dbg(tb, "suspend finished\n"); + + return 0; +} + +static void tb_restore_children(struct tb_switch *sw) +{ + struct tb_port *port; + + /* No need to restore if the router is already unplugged */ + if (sw->is_unplugged) + return; + + if (tb_enable_tmu(sw)) + tb_sw_warn(sw, "failed to restore TMU configuration\n"); + + tb_switch_for_each_port(sw, port) { + if (!tb_port_has_remote(port) && !port->xdomain) + continue; + + if (port->remote) { + tb_switch_lane_bonding_enable(port->remote->sw); + tb_switch_configure_link(port->remote->sw); + + tb_restore_children(port->remote->sw); + } else if (port->xdomain) { + tb_port_configure_xdomain(port); + } + } +} + +static int tb_resume_noirq(struct tb *tb) +{ + struct tb_cm *tcm = tb_priv(tb); + struct tb_tunnel *tunnel, *n; + + tb_dbg(tb, "resuming...\n"); + + /* remove any pci devices the firmware might have setup */ + tb_switch_reset(tb->root_switch); + + tb_switch_resume(tb->root_switch); + tb_free_invalid_tunnels(tb); + tb_free_unplugged_children(tb->root_switch); + tb_restore_children(tb->root_switch); + list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) + tb_tunnel_restart(tunnel); + if (!list_empty(&tcm->tunnel_list)) { + /* + * the pcie links need some time to get going. + * 100ms works for me... + */ + tb_dbg(tb, "tunnels restarted, sleeping for 100ms\n"); + msleep(100); + } + /* Allow tb_handle_hotplug to progress events */ + tcm->hotplug_active = true; + tb_dbg(tb, "resume finished\n"); + + return 0; +} + +static int tb_free_unplugged_xdomains(struct tb_switch *sw) +{ + struct tb_port *port; + int ret = 0; + + tb_switch_for_each_port(sw, port) { + if (tb_is_upstream_port(port)) + continue; + if (port->xdomain && port->xdomain->is_unplugged) { + tb_retimer_remove_all(port); + tb_xdomain_remove(port->xdomain); + tb_port_unconfigure_xdomain(port); + port->xdomain = NULL; + ret++; + } else if (port->remote) { + ret += tb_free_unplugged_xdomains(port->remote->sw); + } + } + + return ret; +} + +static int tb_freeze_noirq(struct tb *tb) +{ + struct tb_cm *tcm = tb_priv(tb); + + tcm->hotplug_active = false; + return 0; +} + +static int tb_thaw_noirq(struct tb *tb) +{ + struct tb_cm *tcm = tb_priv(tb); + + tcm->hotplug_active = true; + return 0; +} + +static void tb_complete(struct tb *tb) +{ + /* + * Release any unplugged XDomains and if there is a case where + * another domain is swapped in place of unplugged XDomain we + * need to run another rescan. + */ + mutex_lock(&tb->lock); + if (tb_free_unplugged_xdomains(tb->root_switch)) + tb_scan_switch(tb->root_switch); + mutex_unlock(&tb->lock); +} + +static int tb_runtime_suspend(struct tb *tb) +{ + struct tb_cm *tcm = tb_priv(tb); + + mutex_lock(&tb->lock); + tb_switch_suspend(tb->root_switch, true); + tcm->hotplug_active = false; + mutex_unlock(&tb->lock); + + return 0; +} + +static void tb_remove_work(struct work_struct *work) +{ + struct tb_cm *tcm = container_of(work, struct tb_cm, remove_work.work); + struct tb *tb = tcm_to_tb(tcm); + + mutex_lock(&tb->lock); + if (tb->root_switch) { + tb_free_unplugged_children(tb->root_switch); + tb_free_unplugged_xdomains(tb->root_switch); + } + mutex_unlock(&tb->lock); +} + +static int tb_runtime_resume(struct tb *tb) +{ + struct tb_cm *tcm = tb_priv(tb); + struct tb_tunnel *tunnel, *n; + + mutex_lock(&tb->lock); + tb_switch_resume(tb->root_switch); + tb_free_invalid_tunnels(tb); + tb_restore_children(tb->root_switch); + list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) + tb_tunnel_restart(tunnel); + tcm->hotplug_active = true; + mutex_unlock(&tb->lock); + + /* + * Schedule cleanup of any unplugged devices. Run this in a + * separate thread to avoid possible deadlock if the device + * removal runtime resumes the unplugged device. + */ + queue_delayed_work(tb->wq, &tcm->remove_work, msecs_to_jiffies(50)); + return 0; +} + +static const struct tb_cm_ops tb_cm_ops = { + .start = tb_start, + .stop = tb_stop, + .suspend_noirq = tb_suspend_noirq, + .resume_noirq = tb_resume_noirq, + .freeze_noirq = tb_freeze_noirq, + .thaw_noirq = tb_thaw_noirq, + .complete = tb_complete, + .runtime_suspend = tb_runtime_suspend, + .runtime_resume = tb_runtime_resume, + .handle_event = tb_handle_event, + .approve_switch = tb_tunnel_pci, + .approve_xdomain_paths = tb_approve_xdomain_paths, + .disconnect_xdomain_paths = tb_disconnect_xdomain_paths, +}; + +struct tb *tb_probe(struct tb_nhi *nhi) +{ + struct tb_cm *tcm; + struct tb *tb; + + tb = tb_domain_alloc(nhi, sizeof(*tcm)); + if (!tb) + return NULL; + + tb->security_level = TB_SECURITY_USER; + tb->cm_ops = &tb_cm_ops; + + tcm = tb_priv(tb); + INIT_LIST_HEAD(&tcm->tunnel_list); + INIT_LIST_HEAD(&tcm->dp_resources); + INIT_DELAYED_WORK(&tcm->remove_work, tb_remove_work); + + return tb; +} |