diff options
Diffstat (limited to 'drivers/thunderbolt/tb.c')
| -rw-r--r-- | drivers/thunderbolt/tb.c | 2467 |
1 files changed, 2467 insertions, 0 deletions
diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c new file mode 100644 index 0000000000..27bd6ca6f9 --- /dev/null +++ b/drivers/thunderbolt/tb.c @@ -0,0 +1,2467 @@ +// 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 <linux/platform_data/x86/apple.h> + +#include "tb.h" +#include "tb_regs.h" +#include "tunnel.h" + +#define TB_TIMEOUT 100 /* ms */ +#define MAX_GROUPS 7 /* max Group_ID is 7 */ + +/** + * 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 + * @groups: Bandwidth groups used in this domain. + */ +struct tb_cm { + struct list_head tunnel_list; + struct list_head dp_resources; + bool hotplug_active; + struct delayed_work remove_work; + struct tb_bandwidth_group groups[MAX_GROUPS]; +}; + +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_init_bandwidth_groups(struct tb_cm *tcm) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(tcm->groups); i++) { + struct tb_bandwidth_group *group = &tcm->groups[i]; + + group->tb = tcm_to_tb(tcm); + group->index = i + 1; + INIT_LIST_HEAD(&group->ports); + } +} + +static void tb_bandwidth_group_attach_port(struct tb_bandwidth_group *group, + struct tb_port *in) +{ + if (!group || WARN_ON(in->group)) + return; + + in->group = group; + list_add_tail(&in->group_list, &group->ports); + + tb_port_dbg(in, "attached to bandwidth group %d\n", group->index); +} + +static struct tb_bandwidth_group *tb_find_free_bandwidth_group(struct tb_cm *tcm) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(tcm->groups); i++) { + struct tb_bandwidth_group *group = &tcm->groups[i]; + + if (list_empty(&group->ports)) + return group; + } + + return NULL; +} + +static struct tb_bandwidth_group * +tb_attach_bandwidth_group(struct tb_cm *tcm, struct tb_port *in, + struct tb_port *out) +{ + struct tb_bandwidth_group *group; + struct tb_tunnel *tunnel; + + /* + * Find all DP tunnels that go through all the same USB4 links + * as this one. Because we always setup tunnels the same way we + * can just check for the routers at both ends of the tunnels + * and if they are the same we have a match. + */ + list_for_each_entry(tunnel, &tcm->tunnel_list, list) { + if (!tb_tunnel_is_dp(tunnel)) + continue; + + if (tunnel->src_port->sw == in->sw && + tunnel->dst_port->sw == out->sw) { + group = tunnel->src_port->group; + if (group) { + tb_bandwidth_group_attach_port(group, in); + return group; + } + } + } + + /* Pick up next available group then */ + group = tb_find_free_bandwidth_group(tcm); + if (group) + tb_bandwidth_group_attach_port(group, in); + else + tb_port_warn(in, "no available bandwidth groups\n"); + + return group; +} + +static void tb_discover_bandwidth_group(struct tb_cm *tcm, struct tb_port *in, + struct tb_port *out) +{ + if (usb4_dp_port_bandwidth_mode_enabled(in)) { + int index, i; + + index = usb4_dp_port_group_id(in); + for (i = 0; i < ARRAY_SIZE(tcm->groups); i++) { + if (tcm->groups[i].index == index) { + tb_bandwidth_group_attach_port(&tcm->groups[i], in); + return; + } + } + } + + tb_attach_bandwidth_group(tcm, in, out); +} + +static void tb_detach_bandwidth_group(struct tb_port *in) +{ + struct tb_bandwidth_group *group = in->group; + + if (group) { + in->group = NULL; + list_del_init(&in->group_list); + + tb_port_dbg(in, "detached from bandwidth group %d\n", group->index); + } +} + +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_dp_resource(struct tb *tb, struct tb_port *port) +{ + struct tb_cm *tcm = tb_priv(tb); + struct tb_port *p; + + list_for_each_entry(p, &tcm->dp_resources, list) { + if (p == port) + return; + } + + tb_port_dbg(port, "DP %s resource available discovered\n", + tb_port_is_dpin(port) ? "IN" : "OUT"); + list_add_tail(&port->list, &tcm->dp_resources); +} + +static void tb_discover_dp_resources(struct tb *tb) +{ + struct tb_cm *tcm = tb_priv(tb); + struct tb_tunnel *tunnel; + + list_for_each_entry(tunnel, &tcm->tunnel_list, list) { + if (tb_tunnel_is_dp(tunnel)) + tb_discover_dp_resource(tb, tunnel->dst_port); + } +} + +/* Enables CL states up to host router */ +static int tb_enable_clx(struct tb_switch *sw) +{ + struct tb_cm *tcm = tb_priv(sw->tb); + unsigned int clx = TB_CL0S | TB_CL1; + const struct tb_tunnel *tunnel; + int ret; + + /* + * Currently only enable CLx for the first link. This is enough + * to allow the CPU to save energy at least on Intel hardware + * and makes it slightly simpler to implement. We may change + * this in the future to cover the whole topology if it turns + * out to be beneficial. + */ + while (sw && sw->config.depth > 1) + sw = tb_switch_parent(sw); + + if (!sw) + return 0; + + if (sw->config.depth != 1) + return 0; + + /* + * If we are re-enabling then check if there is an active DMA + * tunnel and in that case bail out. + */ + list_for_each_entry(tunnel, &tcm->tunnel_list, list) { + if (tb_tunnel_is_dma(tunnel)) { + if (tb_tunnel_port_on_path(tunnel, tb_upstream_port(sw))) + return 0; + } + } + + /* + * Initially try with CL2. If that's not supported by the + * topology try with CL0s and CL1 and then give up. + */ + ret = tb_switch_clx_enable(sw, clx | TB_CL2); + if (ret == -EOPNOTSUPP) + ret = tb_switch_clx_enable(sw, clx); + return ret == -EOPNOTSUPP ? 0 : ret; +} + +/* Disables CL states up to the host router */ +static void tb_disable_clx(struct tb_switch *sw) +{ + do { + if (tb_switch_clx_disable(sw) < 0) + tb_sw_warn(sw, "failed to disable CL states\n"); + sw = tb_switch_parent(sw); + } while (sw); +} + +static int tb_increase_switch_tmu_accuracy(struct device *dev, void *data) +{ + struct tb_switch *sw; + + sw = tb_to_switch(dev); + if (!sw) + return 0; + + if (tb_switch_tmu_is_configured(sw, TB_SWITCH_TMU_MODE_LOWRES)) { + enum tb_switch_tmu_mode mode; + int ret; + + if (tb_switch_clx_is_enabled(sw, TB_CL1)) + mode = TB_SWITCH_TMU_MODE_HIFI_UNI; + else + mode = TB_SWITCH_TMU_MODE_HIFI_BI; + + ret = tb_switch_tmu_configure(sw, mode); + if (ret) + return ret; + + return tb_switch_tmu_enable(sw); + } + + return 0; +} + +static void tb_increase_tmu_accuracy(struct tb_tunnel *tunnel) +{ + struct tb_switch *sw; + + if (!tunnel) + return; + + /* + * Once first DP tunnel is established we change the TMU + * accuracy of first depth child routers (and the host router) + * to the highest. This is needed for the DP tunneling to work + * but also allows CL0s. + * + * If both routers are v2 then we don't need to do anything as + * they are using enhanced TMU mode that allows all CLx. + */ + sw = tunnel->tb->root_switch; + device_for_each_child(&sw->dev, NULL, tb_increase_switch_tmu_accuracy); +} + +static int tb_enable_tmu(struct tb_switch *sw) +{ + int ret; + + /* + * If both routers at the end of the link are v2 we simply + * enable the enhanched uni-directional mode. That covers all + * the CL states. For v1 and before we need to use the normal + * rate to allow CL1 (when supported). Otherwise we keep the TMU + * running at the highest accuracy. + */ + ret = tb_switch_tmu_configure(sw, + TB_SWITCH_TMU_MODE_MEDRES_ENHANCED_UNI); + if (ret == -EOPNOTSUPP) { + if (tb_switch_clx_is_enabled(sw, TB_CL1)) + ret = tb_switch_tmu_configure(sw, + TB_SWITCH_TMU_MODE_LOWRES); + else + ret = tb_switch_tmu_configure(sw, + TB_SWITCH_TMU_MODE_HIFI_BI); + } + if (ret) + return 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); +} + +static void tb_switch_discover_tunnels(struct tb_switch *sw, + struct list_head *list, + bool alloc_hopids) +{ + struct tb *tb = sw->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, alloc_hopids); + tb_increase_tmu_accuracy(tunnel); + break; + + case TB_TYPE_PCIE_DOWN: + tunnel = tb_tunnel_discover_pci(tb, port, alloc_hopids); + break; + + case TB_TYPE_USB3_DOWN: + tunnel = tb_tunnel_discover_usb3(tb, port, alloc_hopids); + break; + + default: + break; + } + + if (tunnel) + list_add_tail(&tunnel->list, list); + } + + tb_switch_for_each_port(sw, port) { + if (tb_port_has_remote(port)) { + tb_switch_discover_tunnels(port->remote->sw, list, + alloc_hopids); + } + } +} + +static void tb_discover_tunnels(struct tb *tb) +{ + struct tb_cm *tcm = tb_priv(tb); + struct tb_tunnel *tunnel; + + tb_switch_discover_tunnels(tb->root_switch, &tcm->tunnel_list, true); + + list_for_each_entry(tunnel, &tcm->tunnel_list, list) { + 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)) { + struct tb_port *in = tunnel->src_port; + struct tb_port *out = tunnel->dst_port; + + /* Keep the domain from powering down */ + pm_runtime_get_sync(&in->sw->dev); + pm_runtime_get_sync(&out->sw->dev); + + tb_discover_bandwidth_group(tcm, in, out); + } + } +} + +static int tb_port_configure_xdomain(struct tb_port *port, struct tb_xdomain *xd) +{ + if (tb_switch_is_usb4(port->sw)) + return usb4_port_configure_xdomain(port, xd); + 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; + + if (!tb_is_xdomain_enabled()) + return; + + 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, xd); + tb_xdomain_add(xd); + } +} + +/** + * 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_dbg(tb, "calculating available bandwidth between %llx:%u <-> %llx:%u\n", + tb_route(src_port->sw), src_port->port, tb_route(dst_port->sw), + dst_port->port); + + tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port); + if (tunnel && tunnel->src_port != src_port && + tunnel->dst_port != dst_port) { + 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; + } + + /* Maximum possible bandwidth asymmetric Gen 4 link is 120 Gb/s */ + *available_up = *available_down = 120000; + + /* 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; + /* + * sw->link_width is from upstream perspective + * so we use the opposite for downstream of the + * host router. + */ + if (port->sw->link_width == TB_LINK_WIDTH_ASYM_TX) { + up_bw = link_speed * 3 * 1000; + down_bw = link_speed * 1 * 1000; + } else if (port->sw->link_width == TB_LINK_WIDTH_ASYM_RX) { + up_bw = link_speed * 1 * 1000; + down_bw = link_speed * 3 * 1000; + } else { + up_bw = link_speed * port->sw->link_width * 1000; + down_bw = up_bw; + } + } else { + link_speed = tb_port_get_link_speed(port); + if (link_speed < 0) + return link_speed; + + link_width = tb_port_get_link_width(port); + if (link_width < 0) + return link_width; + + if (link_width == TB_LINK_WIDTH_ASYM_TX) { + up_bw = link_speed * 1 * 1000; + down_bw = link_speed * 3 * 1000; + } else if (link_width == TB_LINK_WIDTH_ASYM_RX) { + up_bw = link_speed * 3 * 1000; + down_bw = link_speed * 1 * 1000; + } else { + up_bw = link_speed * link_width * 1000; + down_bw = up_bw; + } + } + + /* Leave 10% guard band */ + up_bw -= up_bw / 10; + down_bw -= down_bw / 10; + + tb_port_dbg(port, "link total bandwidth %d/%d Mb/s\n", up_bw, + down_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_invalid(tunnel)) + continue; + + if (!tb_tunnel_is_dp(tunnel)) + continue; + + if (!tb_tunnel_port_on_path(tunnel, port)) + continue; + + /* + * Ignore the DP tunnel between src_port and + * dst_port because it is the same tunnel and we + * may be re-calculating estimated bandwidth. + */ + if (tunnel->src_port == src_port && + tunnel->dst_port == dst_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; + + if (!tb_acpi_may_tunnel_usb3()) { + tb_dbg(tb, "USB3 tunneling disabled, not creating tunnel\n"); + return 0; + } + + 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_switch_downstream_port(sw); + 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_acpi_may_tunnel_usb3()) + return 0; + + 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; + bool discovery = false; + 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 (port->usb4) + pm_runtime_get_sync(&port->usb4->dev); + + if (tb_wait_for_port(port, false) <= 0) + goto out_rpm_put; + if (port->remote) { + tb_port_dbg(port, "port already has a remote\n"); + goto out_rpm_put; + } + + tb_retimer_scan(port, true); + + 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); + goto out_rpm_put; + } + + if (tb_switch_configure(sw)) { + tb_switch_put(sw); + goto out_rpm_put; + } + + /* + * 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); + discovery = 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); + goto out_rpm_put; + } + + /* 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); + /* + * CL0s and CL1 are enabled and supported together. + * Silently ignore CLx enabling in case CLx is not supported. + */ + if (discovery) + tb_sw_dbg(sw, "discovery, not touching CL states\n"); + else if (tb_enable_clx(sw)) + tb_sw_warn(sw, "failed to enable CL states\n"); + + if (tb_enable_tmu(sw)) + tb_sw_warn(sw, "failed to enable TMU\n"); + + /* + * Configuration valid needs to be set after the TMU has been + * enabled for the upstream port of the router so we do it here. + */ + tb_switch_configuration_valid(sw); + + /* Scan upstream retimers */ + tb_retimer_scan(upstream_port, true); + + /* + * 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); + +out_rpm_put: + if (port->usb4) { + pm_runtime_mark_last_busy(&port->usb4->dev); + pm_runtime_put_autosuspend(&port->usb4->dev); + } +} + +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: + tb_detach_bandwidth_group(src_port); + /* + * 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 void +tb_recalc_estimated_bandwidth_for_group(struct tb_bandwidth_group *group) +{ + struct tb_tunnel *first_tunnel; + struct tb *tb = group->tb; + struct tb_port *in; + int ret; + + tb_dbg(tb, "re-calculating bandwidth estimation for group %u\n", + group->index); + + first_tunnel = NULL; + list_for_each_entry(in, &group->ports, group_list) { + int estimated_bw, estimated_up, estimated_down; + struct tb_tunnel *tunnel; + struct tb_port *out; + + if (!usb4_dp_port_bandwidth_mode_enabled(in)) + continue; + + tunnel = tb_find_tunnel(tb, TB_TUNNEL_DP, in, NULL); + if (WARN_ON(!tunnel)) + break; + + if (!first_tunnel) { + /* + * Since USB3 bandwidth is shared by all DP + * tunnels under the host router USB4 port, even + * if they do not begin from the host router, we + * can release USB3 bandwidth just once and not + * for each tunnel separately. + */ + first_tunnel = tunnel; + ret = tb_release_unused_usb3_bandwidth(tb, + first_tunnel->src_port, first_tunnel->dst_port); + if (ret) { + tb_port_warn(in, + "failed to release unused bandwidth\n"); + break; + } + } + + out = tunnel->dst_port; + ret = tb_available_bandwidth(tb, in, out, &estimated_up, + &estimated_down); + if (ret) { + tb_port_warn(in, + "failed to re-calculate estimated bandwidth\n"); + break; + } + + /* + * Estimated bandwidth includes: + * - already allocated bandwidth for the DP tunnel + * - available bandwidth along the path + * - bandwidth allocated for USB 3.x but not used. + */ + tb_port_dbg(in, "re-calculated estimated bandwidth %u/%u Mb/s\n", + estimated_up, estimated_down); + + if (in->sw->config.depth < out->sw->config.depth) + estimated_bw = estimated_down; + else + estimated_bw = estimated_up; + + if (usb4_dp_port_set_estimated_bandwidth(in, estimated_bw)) + tb_port_warn(in, "failed to update estimated bandwidth\n"); + } + + if (first_tunnel) + tb_reclaim_usb3_bandwidth(tb, first_tunnel->src_port, + first_tunnel->dst_port); + + tb_dbg(tb, "bandwidth estimation for group %u done\n", group->index); +} + +static void tb_recalc_estimated_bandwidth(struct tb *tb) +{ + struct tb_cm *tcm = tb_priv(tb); + int i; + + tb_dbg(tb, "bandwidth consumption changed, re-calculating estimated bandwidth\n"); + + for (i = 0; i < ARRAY_SIZE(tcm->groups); i++) { + struct tb_bandwidth_group *group = &tcm->groups[i]; + + if (!list_empty(&group->ports)) + tb_recalc_estimated_bandwidth_for_group(group); + } + + tb_dbg(tb, "bandwidth re-calculation done\n"); +} + +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, "DP OUT 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, link_nr; + struct tb_cm *tcm = tb_priv(tb); + struct tb_port *port, *in, *out; + struct tb_tunnel *tunnel; + + if (!tb_acpi_may_tunnel_dp()) { + tb_dbg(tb, "DP tunneling disabled, not creating tunnel\n"); + return; + } + + /* + * 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, "DP IN 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; + } + + /* + * This is only applicable to links that are not bonded (so + * when Thunderbolt 1 hardware is involved somewhere in the + * topology). For these try to share the DP bandwidth between + * the two lanes. + */ + link_nr = 1; + list_for_each_entry(tunnel, &tcm->tunnel_list, list) { + if (tb_tunnel_is_dp(tunnel)) { + link_nr = 0; + break; + } + } + + /* + * 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; + } + + if (!tb_attach_bandwidth_group(tcm, in, out)) + goto err_dealloc_dp; + + /* 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_detach_group; + } + + ret = tb_available_bandwidth(tb, in, out, &available_up, &available_down); + if (ret) + goto err_reclaim_usb; + + 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, link_nr, available_up, + available_down); + if (!tunnel) { + tb_port_dbg(out, "could not allocate DP tunnel\n"); + goto err_reclaim_usb; + } + + 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); + + /* Update the domain with the new bandwidth estimation */ + tb_recalc_estimated_bandwidth(tb); + + /* + * In case of DP tunnel exists, change host router's 1st children + * TMU mode to HiFi for CL0s to work. + */ + tb_increase_tmu_accuracy(tunnel); + return; + +err_free: + tb_tunnel_free(tunnel); +err_reclaim_usb: + tb_reclaim_usb3_bandwidth(tb, in, out); +err_detach_group: + tb_detach_bandwidth_group(in); +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_recalc_estimated_bandwidth(tb); + 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_disconnect_pci(struct tb *tb, struct tb_switch *sw) +{ + struct tb_tunnel *tunnel; + struct tb_port *up; + + up = tb_switch_find_port(sw, TB_TYPE_PCIE_UP); + if (WARN_ON(!up)) + return -ENODEV; + + tunnel = tb_find_tunnel(tb, TB_TUNNEL_PCI, NULL, up); + if (WARN_ON(!tunnel)) + return -ENODEV; + + tb_switch_xhci_disconnect(sw); + + tb_tunnel_deactivate(tunnel); + list_del(&tunnel->list); + tb_tunnel_free(tunnel); + return 0; +} + +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_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. + */ + port = tb_switch_downstream_port(sw); + down = tb_find_pcie_down(tb_switch_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; + } + + /* + * PCIe L1 is needed to enable CL0s for Titan Ridge so enable it + * here. + */ + if (tb_switch_pcie_l1_enable(sw)) + tb_sw_warn(sw, "failed to enable PCIe L1 for Titan Ridge\n"); + + if (tb_switch_xhci_connect(sw)) + tb_sw_warn(sw, "failed to connect xHCI\n"); + + list_add_tail(&tunnel->list, &tcm->tunnel_list); + return 0; +} + +static int tb_approve_xdomain_paths(struct tb *tb, struct tb_xdomain *xd, + int transmit_path, int transmit_ring, + int receive_path, int receive_ring) +{ + struct tb_cm *tcm = tb_priv(tb); + struct tb_port *nhi_port, *dst_port; + struct tb_tunnel *tunnel; + struct tb_switch *sw; + int ret; + + 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); + + /* + * When tunneling DMA paths the link should not enter CL states + * so disable them now. + */ + tb_disable_clx(sw); + + tunnel = tb_tunnel_alloc_dma(tb, nhi_port, dst_port, transmit_path, + transmit_ring, receive_path, receive_ring); + if (!tunnel) { + ret = -ENOMEM; + goto err_clx; + } + + if (tb_tunnel_activate(tunnel)) { + tb_port_info(nhi_port, + "DMA tunnel activation failed, aborting\n"); + ret = -EIO; + goto err_free; + } + + list_add_tail(&tunnel->list, &tcm->tunnel_list); + mutex_unlock(&tb->lock); + return 0; + +err_free: + tb_tunnel_free(tunnel); +err_clx: + tb_enable_clx(sw); + mutex_unlock(&tb->lock); + + return ret; +} + +static void __tb_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd, + int transmit_path, int transmit_ring, + int receive_path, int receive_ring) +{ + struct tb_cm *tcm = tb_priv(tb); + struct tb_port *nhi_port, *dst_port; + struct tb_tunnel *tunnel, *n; + 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); + + list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) { + if (!tb_tunnel_is_dma(tunnel)) + continue; + if (tunnel->src_port != nhi_port || tunnel->dst_port != dst_port) + continue; + + if (tb_tunnel_match_dma(tunnel, transmit_path, transmit_ring, + receive_path, receive_ring)) + tb_deactivate_and_free_tunnel(tunnel); + } + + /* + * Try to re-enable CL states now, it is OK if this fails + * because we may still have another DMA tunnel active through + * the same host router USB4 downstream port. + */ + tb_enable_clx(sw); +} + +static int tb_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd, + int transmit_path, int transmit_ring, + int receive_path, int receive_ring) +{ + if (!xd->is_unplugged) { + mutex_lock(&tb->lock); + __tb_disconnect_xdomain_paths(tb, xd, transmit_path, + transmit_ring, receive_path, + receive_ring); + 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_recalc_estimated_bandwidth(tb); + 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 + * all the tunnels below. + */ + xd->is_unplugged = true; + tb_xdomain_remove(xd); + port->xdomain = NULL; + __tb_disconnect_xdomain_paths(tb, xd, -1, -1, -1, -1); + 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 if (!port->port) { + tb_sw_dbg(sw, "xHCI disconnect request\n"); + tb_switch_xhci_disconnect(sw); + } 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 (!port->port && sw->authorized) { + tb_sw_dbg(sw, "xHCI connect request\n"); + tb_switch_xhci_connect(sw); + } 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); +} + +static int tb_alloc_dp_bandwidth(struct tb_tunnel *tunnel, int *requested_up, + int *requested_down) +{ + int allocated_up, allocated_down, available_up, available_down, ret; + int requested_up_corrected, requested_down_corrected, granularity; + int max_up, max_down, max_up_rounded, max_down_rounded; + struct tb *tb = tunnel->tb; + struct tb_port *in, *out; + + ret = tb_tunnel_allocated_bandwidth(tunnel, &allocated_up, &allocated_down); + if (ret) + return ret; + + in = tunnel->src_port; + out = tunnel->dst_port; + + tb_port_dbg(in, "bandwidth allocated currently %d/%d Mb/s\n", + allocated_up, allocated_down); + + /* + * If we get rounded up request from graphics side, say HBR2 x 4 + * that is 17500 instead of 17280 (this is because of the + * granularity), we allow it too. Here the graphics has already + * negotiated with the DPRX the maximum possible rates (which is + * 17280 in this case). + * + * Since the link cannot go higher than 17280 we use that in our + * calculations but the DP IN adapter Allocated BW write must be + * the same value (17500) otherwise the adapter will mark it as + * failed for graphics. + */ + ret = tb_tunnel_maximum_bandwidth(tunnel, &max_up, &max_down); + if (ret) + return ret; + + ret = usb4_dp_port_granularity(in); + if (ret < 0) + return ret; + granularity = ret; + + max_up_rounded = roundup(max_up, granularity); + max_down_rounded = roundup(max_down, granularity); + + /* + * This will "fix" the request down to the maximum supported + * rate * lanes if it is at the maximum rounded up level. + */ + requested_up_corrected = *requested_up; + if (requested_up_corrected == max_up_rounded) + requested_up_corrected = max_up; + else if (requested_up_corrected < 0) + requested_up_corrected = 0; + requested_down_corrected = *requested_down; + if (requested_down_corrected == max_down_rounded) + requested_down_corrected = max_down; + else if (requested_down_corrected < 0) + requested_down_corrected = 0; + + tb_port_dbg(in, "corrected bandwidth request %d/%d Mb/s\n", + requested_up_corrected, requested_down_corrected); + + if ((*requested_up >= 0 && requested_up_corrected > max_up_rounded) || + (*requested_down >= 0 && requested_down_corrected > max_down_rounded)) { + tb_port_dbg(in, "bandwidth request too high (%d/%d Mb/s > %d/%d Mb/s)\n", + requested_up_corrected, requested_down_corrected, + max_up_rounded, max_down_rounded); + return -ENOBUFS; + } + + if ((*requested_up >= 0 && requested_up_corrected <= allocated_up) || + (*requested_down >= 0 && requested_down_corrected <= allocated_down)) { + /* + * If requested bandwidth is less or equal than what is + * currently allocated to that tunnel we simply change + * the reservation of the tunnel. Since all the tunnels + * going out from the same USB4 port are in the same + * group the released bandwidth will be taken into + * account for the other tunnels automatically below. + */ + return tb_tunnel_alloc_bandwidth(tunnel, requested_up, + requested_down); + } + + /* + * More bandwidth is requested. Release all the potential + * bandwidth from USB3 first. + */ + ret = tb_release_unused_usb3_bandwidth(tb, in, out); + if (ret) + return ret; + + /* + * Then go over all tunnels that cross the same USB4 ports (they + * are also in the same group but we use the same function here + * that we use with the normal bandwidth allocation). + */ + ret = tb_available_bandwidth(tb, in, out, &available_up, &available_down); + if (ret) + goto reclaim; + + tb_port_dbg(in, "bandwidth available for allocation %d/%d Mb/s\n", + available_up, available_down); + + if ((*requested_up >= 0 && available_up >= requested_up_corrected) || + (*requested_down >= 0 && available_down >= requested_down_corrected)) { + ret = tb_tunnel_alloc_bandwidth(tunnel, requested_up, + requested_down); + } else { + ret = -ENOBUFS; + } + +reclaim: + tb_reclaim_usb3_bandwidth(tb, in, out); + return ret; +} + +static void tb_handle_dp_bandwidth_request(struct work_struct *work) +{ + struct tb_hotplug_event *ev = container_of(work, typeof(*ev), work); + int requested_bw, requested_up, requested_down, ret; + struct tb_port *in, *out; + struct tb_tunnel *tunnel; + struct tb *tb = ev->tb; + struct tb_cm *tcm = tb_priv(tb); + struct tb_switch *sw; + + pm_runtime_get_sync(&tb->dev); + + mutex_lock(&tb->lock); + if (!tcm->hotplug_active) + goto unlock; + + sw = tb_switch_find_by_route(tb, ev->route); + if (!sw) { + tb_warn(tb, "bandwidth request from non-existent router %llx\n", + ev->route); + goto unlock; + } + + in = &sw->ports[ev->port]; + if (!tb_port_is_dpin(in)) { + tb_port_warn(in, "bandwidth request to non-DP IN adapter\n"); + goto put_sw; + } + + tb_port_dbg(in, "handling bandwidth allocation request\n"); + + if (!usb4_dp_port_bandwidth_mode_enabled(in)) { + tb_port_warn(in, "bandwidth allocation mode not enabled\n"); + goto put_sw; + } + + ret = usb4_dp_port_requested_bandwidth(in); + if (ret < 0) { + if (ret == -ENODATA) + tb_port_dbg(in, "no bandwidth request active\n"); + else + tb_port_warn(in, "failed to read requested bandwidth\n"); + goto put_sw; + } + requested_bw = ret; + + tb_port_dbg(in, "requested bandwidth %d Mb/s\n", requested_bw); + + tunnel = tb_find_tunnel(tb, TB_TUNNEL_DP, in, NULL); + if (!tunnel) { + tb_port_warn(in, "failed to find tunnel\n"); + goto put_sw; + } + + out = tunnel->dst_port; + + if (in->sw->config.depth < out->sw->config.depth) { + requested_up = -1; + requested_down = requested_bw; + } else { + requested_up = requested_bw; + requested_down = -1; + } + + ret = tb_alloc_dp_bandwidth(tunnel, &requested_up, &requested_down); + if (ret) { + if (ret == -ENOBUFS) + tb_port_warn(in, "not enough bandwidth available\n"); + else + tb_port_warn(in, "failed to change bandwidth allocation\n"); + } else { + tb_port_dbg(in, "bandwidth allocation changed to %d/%d Mb/s\n", + requested_up, requested_down); + + /* Update other clients about the allocation change */ + tb_recalc_estimated_bandwidth(tb); + } + +put_sw: + tb_switch_put(sw); +unlock: + mutex_unlock(&tb->lock); + + pm_runtime_mark_last_busy(&tb->dev); + pm_runtime_put_autosuspend(&tb->dev); + + kfree(ev); +} + +static void tb_queue_dp_bandwidth_request(struct tb *tb, u64 route, u8 port) +{ + struct tb_hotplug_event *ev; + + ev = kmalloc(sizeof(*ev), GFP_KERNEL); + if (!ev) + return; + + ev->tb = tb; + ev->route = route; + ev->port = port; + INIT_WORK(&ev->work, tb_handle_dp_bandwidth_request); + queue_work(tb->wq, &ev->work); +} + +static void tb_handle_notification(struct tb *tb, u64 route, + const struct cfg_error_pkg *error) +{ + + switch (error->error) { + case TB_CFG_ERROR_PCIE_WAKE: + case TB_CFG_ERROR_DP_CON_CHANGE: + case TB_CFG_ERROR_DPTX_DISCOVERY: + if (tb_cfg_ack_notification(tb->ctl, route, error)) + tb_warn(tb, "could not ack notification on %llx\n", + route); + break; + + case TB_CFG_ERROR_DP_BW: + if (tb_cfg_ack_notification(tb->ctl, route, error)) + tb_warn(tb, "could not ack notification on %llx\n", + route); + tb_queue_dp_bandwidth_request(tb, route, error->port); + break; + + default: + /* Ignore for now */ + break; + } +} + +/* + * 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 = tb_cfg_get_route(&pkg->header); + + switch (type) { + case TB_CFG_PKG_ERROR: + tb_handle_notification(tb, route, (const struct cfg_error_pkg *)buf); + return; + case TB_CFG_PKG_EVENT: + break; + default: + tb_warn(tb, "unexpected event %#x, ignoring\n", type); + return; + } + + 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. + * + * However, USB4 routers support NVM firmware upgrade if they + * implement the necessary router operations. + */ + tb->root_switch->no_nvm_upgrade = !tb_switch_is_usb4(tb->root_switch); + /* 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; + } + + /* + * To support highest CLx state, we set host router's TMU to + * Normal mode. + */ + tb_switch_tmu_configure(tb->root_switch, TB_SWITCH_TMU_MODE_LOWRES); + /* 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); + /* Add DP resources from the DP tunnels created by the boot firmware */ + tb_discover_dp_resources(tb); + /* + * 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_clx(sw)) + tb_sw_warn(sw, "failed to re-enable CL states\n"); + + if (tb_enable_tmu(sw)) + tb_sw_warn(sw, "failed to restore TMU configuration\n"); + + tb_switch_configuration_valid(sw); + + 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, port->xdomain); + } + } +} + +static int tb_resume_noirq(struct tb *tb) +{ + struct tb_cm *tcm = tb_priv(tb); + struct tb_tunnel *tunnel, *n; + unsigned int usb3_delay = 0; + LIST_HEAD(tunnels); + + 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); + + /* + * If we get here from suspend to disk the boot firmware or the + * restore kernel might have created tunnels of its own. Since + * we cannot be sure they are usable for us we find and tear + * them down. + */ + tb_switch_discover_tunnels(tb->root_switch, &tunnels, false); + list_for_each_entry_safe_reverse(tunnel, n, &tunnels, list) { + if (tb_tunnel_is_usb3(tunnel)) + usb3_delay = 500; + tb_tunnel_deactivate(tunnel); + tb_tunnel_free(tunnel); + } + + /* Re-create our tunnels now */ + list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) { + /* USB3 requires delay before it can be re-activated */ + if (tb_tunnel_is_usb3(tunnel)) { + msleep(usb3_delay); + /* Only need to do it once */ + usb3_delay = 0; + } + 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, + .disapprove_switch = tb_disconnect_pci, + .approve_switch = tb_tunnel_pci, + .approve_xdomain_paths = tb_approve_xdomain_paths, + .disconnect_xdomain_paths = tb_disconnect_xdomain_paths, +}; + +/* + * During suspend the Thunderbolt controller is reset and all PCIe + * tunnels are lost. The NHI driver will try to reestablish all tunnels + * during resume. This adds device links between the tunneled PCIe + * downstream ports and the NHI so that the device core will make sure + * NHI is resumed first before the rest. + */ +static bool tb_apple_add_links(struct tb_nhi *nhi) +{ + struct pci_dev *upstream, *pdev; + bool ret; + + if (!x86_apple_machine) + return false; + + switch (nhi->pdev->device) { + case PCI_DEVICE_ID_INTEL_LIGHT_RIDGE: + case PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C: + case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_2C_NHI: + case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_4C_NHI: + break; + default: + return false; + } + + upstream = pci_upstream_bridge(nhi->pdev); + while (upstream) { + if (!pci_is_pcie(upstream)) + return false; + if (pci_pcie_type(upstream) == PCI_EXP_TYPE_UPSTREAM) + break; + upstream = pci_upstream_bridge(upstream); + } + + if (!upstream) + return false; + + /* + * For each hotplug downstream port, create add device link + * back to NHI so that PCIe tunnels can be re-established after + * sleep. + */ + ret = false; + for_each_pci_bridge(pdev, upstream->subordinate) { + const struct device_link *link; + + if (!pci_is_pcie(pdev)) + continue; + if (pci_pcie_type(pdev) != PCI_EXP_TYPE_DOWNSTREAM || + !pdev->is_hotplug_bridge) + continue; + + link = device_link_add(&pdev->dev, &nhi->pdev->dev, + DL_FLAG_AUTOREMOVE_SUPPLIER | + DL_FLAG_PM_RUNTIME); + if (link) { + dev_dbg(&nhi->pdev->dev, "created link from %s\n", + dev_name(&pdev->dev)); + ret = true; + } else { + dev_warn(&nhi->pdev->dev, "device link creation from %s failed\n", + dev_name(&pdev->dev)); + } + } + + return ret; +} + +struct tb *tb_probe(struct tb_nhi *nhi) +{ + struct tb_cm *tcm; + struct tb *tb; + + tb = tb_domain_alloc(nhi, TB_TIMEOUT, sizeof(*tcm)); + if (!tb) + return NULL; + + if (tb_acpi_may_tunnel_pcie()) + tb->security_level = TB_SECURITY_USER; + else + tb->security_level = TB_SECURITY_NOPCIE; + + 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); + tb_init_bandwidth_groups(tcm); + + tb_dbg(tb, "using software connection manager\n"); + + /* + * Device links are needed to make sure we establish tunnels + * before the PCIe/USB stack is resumed so complain here if we + * found them missing. + */ + if (!tb_apple_add_links(nhi) && !tb_acpi_add_links(nhi)) + tb_warn(tb, "device links to tunneled native ports are missing!\n"); + + return tb; +} |