// SPDX-License-Identifier: GPL-2.0 /* * Thunderbolt driver - Tunneling support * * Copyright (c) 2014 Andreas Noever * Copyright (C) 2019, Intel Corporation */ #include #include #include #include #include #include "tunnel.h" #include "tb.h" /* PCIe adapters use always HopID of 8 for both directions */ #define TB_PCI_HOPID 8 #define TB_PCI_PATH_DOWN 0 #define TB_PCI_PATH_UP 1 #define TB_PCI_PRIORITY 3 #define TB_PCI_WEIGHT 1 /* USB3 adapters use always HopID of 8 for both directions */ #define TB_USB3_HOPID 8 #define TB_USB3_PATH_DOWN 0 #define TB_USB3_PATH_UP 1 #define TB_USB3_PRIORITY 3 #define TB_USB3_WEIGHT 2 /* DP adapters use HopID 8 for AUX and 9 for Video */ #define TB_DP_AUX_TX_HOPID 8 #define TB_DP_AUX_RX_HOPID 8 #define TB_DP_VIDEO_HOPID 9 #define TB_DP_VIDEO_PATH_OUT 0 #define TB_DP_AUX_PATH_OUT 1 #define TB_DP_AUX_PATH_IN 2 #define TB_DP_VIDEO_PRIORITY 1 #define TB_DP_VIDEO_WEIGHT 1 #define TB_DP_AUX_PRIORITY 2 #define TB_DP_AUX_WEIGHT 1 /* Minimum number of credits needed for PCIe path */ #define TB_MIN_PCIE_CREDITS 6U /* * Number of credits we try to allocate for each DMA path if not limited * by the host router baMaxHI. */ #define TB_DMA_CREDITS 14 /* Minimum number of credits for DMA path */ #define TB_MIN_DMA_CREDITS 1 #define TB_DMA_PRIORITY 5 #define TB_DMA_WEIGHT 1 /* * Reserve additional bandwidth for USB 3.x and PCIe bulk traffic * according to USB4 v2 Connection Manager guide. This ends up reserving * 1500 Mb/s for PCIe and 3000 Mb/s for USB 3.x taking weights into * account. */ #define USB4_V2_PCI_MIN_BANDWIDTH (1500 * TB_PCI_WEIGHT) #define USB4_V2_USB3_MIN_BANDWIDTH (1500 * TB_USB3_WEIGHT) static unsigned int dma_credits = TB_DMA_CREDITS; module_param(dma_credits, uint, 0444); MODULE_PARM_DESC(dma_credits, "specify custom credits for DMA tunnels (default: " __MODULE_STRING(TB_DMA_CREDITS) ")"); static bool bw_alloc_mode = true; module_param(bw_alloc_mode, bool, 0444); MODULE_PARM_DESC(bw_alloc_mode, "enable bandwidth allocation mode if supported (default: true)"); static const char * const tb_tunnel_names[] = { "PCI", "DP", "DMA", "USB3" }; static inline unsigned int tb_usable_credits(const struct tb_port *port) { return port->total_credits - port->ctl_credits; } /** * tb_available_credits() - Available credits for PCIe and DMA * @port: Lane adapter to check * @max_dp_streams: If non-%NULL stores maximum number of simultaneous DP * streams possible through this lane adapter */ static unsigned int tb_available_credits(const struct tb_port *port, size_t *max_dp_streams) { const struct tb_switch *sw = port->sw; int credits, usb3, pcie, spare; size_t ndp; usb3 = tb_acpi_may_tunnel_usb3() ? sw->max_usb3_credits : 0; pcie = tb_acpi_may_tunnel_pcie() ? sw->max_pcie_credits : 0; if (tb_acpi_is_xdomain_allowed()) { spare = min_not_zero(sw->max_dma_credits, dma_credits); /* Add some credits for potential second DMA tunnel */ spare += TB_MIN_DMA_CREDITS; } else { spare = 0; } credits = tb_usable_credits(port); if (tb_acpi_may_tunnel_dp()) { /* * Maximum number of DP streams possible through the * lane adapter. */ if (sw->min_dp_aux_credits + sw->min_dp_main_credits) ndp = (credits - (usb3 + pcie + spare)) / (sw->min_dp_aux_credits + sw->min_dp_main_credits); else ndp = 0; } else { ndp = 0; } credits -= ndp * (sw->min_dp_aux_credits + sw->min_dp_main_credits); credits -= usb3; if (max_dp_streams) *max_dp_streams = ndp; return credits > 0 ? credits : 0; } static void tb_init_pm_support(struct tb_path_hop *hop) { struct tb_port *out_port = hop->out_port; struct tb_port *in_port = hop->in_port; if (tb_port_is_null(in_port) && tb_port_is_null(out_port) && usb4_switch_version(in_port->sw) >= 2) hop->pm_support = true; } static struct tb_tunnel *tb_tunnel_alloc(struct tb *tb, size_t npaths, enum tb_tunnel_type type) { struct tb_tunnel *tunnel; tunnel = kzalloc(sizeof(*tunnel), GFP_KERNEL); if (!tunnel) return NULL; tunnel->paths = kcalloc(npaths, sizeof(tunnel->paths[0]), GFP_KERNEL); if (!tunnel->paths) { tb_tunnel_free(tunnel); return NULL; } INIT_LIST_HEAD(&tunnel->list); tunnel->tb = tb; tunnel->npaths = npaths; tunnel->type = type; return tunnel; } static int tb_pci_set_ext_encapsulation(struct tb_tunnel *tunnel, bool enable) { struct tb_port *port = tb_upstream_port(tunnel->dst_port->sw); int ret; /* Only supported of both routers are at least USB4 v2 */ if ((usb4_switch_version(tunnel->src_port->sw) < 2) || (usb4_switch_version(tunnel->dst_port->sw) < 2)) return 0; if (enable && tb_port_get_link_generation(port) < 4) return 0; ret = usb4_pci_port_set_ext_encapsulation(tunnel->src_port, enable); if (ret) return ret; /* * Downstream router could be unplugged so disable of encapsulation * in upstream router is still possible. */ ret = usb4_pci_port_set_ext_encapsulation(tunnel->dst_port, enable); if (ret) { if (enable) return ret; if (ret != -ENODEV) return ret; } tb_tunnel_dbg(tunnel, "extended encapsulation %s\n", str_enabled_disabled(enable)); return 0; } static int tb_pci_activate(struct tb_tunnel *tunnel, bool activate) { int res; if (activate) { res = tb_pci_set_ext_encapsulation(tunnel, activate); if (res) return res; } if (activate) res = tb_pci_port_enable(tunnel->dst_port, activate); else res = tb_pci_port_enable(tunnel->src_port, activate); if (res) return res; if (activate) { res = tb_pci_port_enable(tunnel->src_port, activate); if (res) return res; } else { /* Downstream router could be unplugged */ tb_pci_port_enable(tunnel->dst_port, activate); } return activate ? 0 : tb_pci_set_ext_encapsulation(tunnel, activate); } static int tb_pci_init_credits(struct tb_path_hop *hop) { struct tb_port *port = hop->in_port; struct tb_switch *sw = port->sw; unsigned int credits; if (tb_port_use_credit_allocation(port)) { unsigned int available; available = tb_available_credits(port, NULL); credits = min(sw->max_pcie_credits, available); if (credits < TB_MIN_PCIE_CREDITS) return -ENOSPC; credits = max(TB_MIN_PCIE_CREDITS, credits); } else { if (tb_port_is_null(port)) credits = port->bonded ? 32 : 16; else credits = 7; } hop->initial_credits = credits; return 0; } static int tb_pci_init_path(struct tb_path *path) { struct tb_path_hop *hop; path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL; path->egress_shared_buffer = TB_PATH_NONE; path->ingress_fc_enable = TB_PATH_ALL; path->ingress_shared_buffer = TB_PATH_NONE; path->priority = TB_PCI_PRIORITY; path->weight = TB_PCI_WEIGHT; path->drop_packages = 0; tb_path_for_each_hop(path, hop) { int ret; ret = tb_pci_init_credits(hop); if (ret) return ret; } return 0; } /** * tb_tunnel_discover_pci() - Discover existing PCIe tunnels * @tb: Pointer to the domain structure * @down: PCIe downstream adapter * @alloc_hopid: Allocate HopIDs from visited ports * * If @down adapter is active, follows the tunnel to the PCIe upstream * adapter and back. Returns the discovered tunnel or %NULL if there was * no tunnel. */ struct tb_tunnel *tb_tunnel_discover_pci(struct tb *tb, struct tb_port *down, bool alloc_hopid) { struct tb_tunnel *tunnel; struct tb_path *path; if (!tb_pci_port_is_enabled(down)) return NULL; tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI); if (!tunnel) return NULL; tunnel->activate = tb_pci_activate; tunnel->src_port = down; /* * Discover both paths even if they are not complete. We will * clean them up by calling tb_tunnel_deactivate() below in that * case. */ path = tb_path_discover(down, TB_PCI_HOPID, NULL, -1, &tunnel->dst_port, "PCIe Up", alloc_hopid); if (!path) { /* Just disable the downstream port */ tb_pci_port_enable(down, false); goto err_free; } tunnel->paths[TB_PCI_PATH_UP] = path; if (tb_pci_init_path(tunnel->paths[TB_PCI_PATH_UP])) goto err_free; path = tb_path_discover(tunnel->dst_port, -1, down, TB_PCI_HOPID, NULL, "PCIe Down", alloc_hopid); if (!path) goto err_deactivate; tunnel->paths[TB_PCI_PATH_DOWN] = path; if (tb_pci_init_path(tunnel->paths[TB_PCI_PATH_DOWN])) goto err_deactivate; /* Validate that the tunnel is complete */ if (!tb_port_is_pcie_up(tunnel->dst_port)) { tb_port_warn(tunnel->dst_port, "path does not end on a PCIe adapter, cleaning up\n"); goto err_deactivate; } if (down != tunnel->src_port) { tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n"); goto err_deactivate; } if (!tb_pci_port_is_enabled(tunnel->dst_port)) { tb_tunnel_warn(tunnel, "tunnel is not fully activated, cleaning up\n"); goto err_deactivate; } tb_tunnel_dbg(tunnel, "discovered\n"); return tunnel; err_deactivate: tb_tunnel_deactivate(tunnel); err_free: tb_tunnel_free(tunnel); return NULL; } /** * tb_tunnel_alloc_pci() - allocate a pci tunnel * @tb: Pointer to the domain structure * @up: PCIe upstream adapter port * @down: PCIe downstream adapter port * * Allocate a PCI tunnel. The ports must be of type TB_TYPE_PCIE_UP and * TB_TYPE_PCIE_DOWN. * * Return: Returns a tb_tunnel on success or NULL on failure. */ struct tb_tunnel *tb_tunnel_alloc_pci(struct tb *tb, struct tb_port *up, struct tb_port *down) { struct tb_tunnel *tunnel; struct tb_path *path; tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI); if (!tunnel) return NULL; tunnel->activate = tb_pci_activate; tunnel->src_port = down; tunnel->dst_port = up; path = tb_path_alloc(tb, down, TB_PCI_HOPID, up, TB_PCI_HOPID, 0, "PCIe Down"); if (!path) goto err_free; tunnel->paths[TB_PCI_PATH_DOWN] = path; if (tb_pci_init_path(path)) goto err_free; path = tb_path_alloc(tb, up, TB_PCI_HOPID, down, TB_PCI_HOPID, 0, "PCIe Up"); if (!path) goto err_free; tunnel->paths[TB_PCI_PATH_UP] = path; if (tb_pci_init_path(path)) goto err_free; return tunnel; err_free: tb_tunnel_free(tunnel); return NULL; } /** * tb_tunnel_reserved_pci() - Amount of bandwidth to reserve for PCIe * @port: Lane 0 adapter * @reserved_up: Upstream bandwidth in Mb/s to reserve * @reserved_down: Downstream bandwidth in Mb/s to reserve * * Can be called to any connected lane 0 adapter to find out how much * bandwidth needs to be left in reserve for possible PCIe bulk traffic. * Returns true if there is something to be reserved and writes the * amount to @reserved_down/@reserved_up. Otherwise returns false and * does not touch the parameters. */ bool tb_tunnel_reserved_pci(struct tb_port *port, int *reserved_up, int *reserved_down) { if (WARN_ON_ONCE(!port->remote)) return false; if (!tb_acpi_may_tunnel_pcie()) return false; if (tb_port_get_link_generation(port) < 4) return false; /* Must have PCIe adapters */ if (tb_is_upstream_port(port)) { if (!tb_switch_find_port(port->sw, TB_TYPE_PCIE_UP)) return false; if (!tb_switch_find_port(port->remote->sw, TB_TYPE_PCIE_DOWN)) return false; } else { if (!tb_switch_find_port(port->sw, TB_TYPE_PCIE_DOWN)) return false; if (!tb_switch_find_port(port->remote->sw, TB_TYPE_PCIE_UP)) return false; } *reserved_up = USB4_V2_PCI_MIN_BANDWIDTH; *reserved_down = USB4_V2_PCI_MIN_BANDWIDTH; tb_port_dbg(port, "reserving %u/%u Mb/s for PCIe\n", *reserved_up, *reserved_down); return true; } static bool tb_dp_is_usb4(const struct tb_switch *sw) { /* Titan Ridge DP adapters need the same treatment as USB4 */ return tb_switch_is_usb4(sw) || tb_switch_is_titan_ridge(sw); } static int tb_dp_cm_handshake(struct tb_port *in, struct tb_port *out, int timeout_msec) { ktime_t timeout = ktime_add_ms(ktime_get(), timeout_msec); u32 val; int ret; /* Both ends need to support this */ if (!tb_dp_is_usb4(in->sw) || !tb_dp_is_usb4(out->sw)) return 0; ret = tb_port_read(out, &val, TB_CFG_PORT, out->cap_adap + DP_STATUS_CTRL, 1); if (ret) return ret; val |= DP_STATUS_CTRL_UF | DP_STATUS_CTRL_CMHS; ret = tb_port_write(out, &val, TB_CFG_PORT, out->cap_adap + DP_STATUS_CTRL, 1); if (ret) return ret; do { ret = tb_port_read(out, &val, TB_CFG_PORT, out->cap_adap + DP_STATUS_CTRL, 1); if (ret) return ret; if (!(val & DP_STATUS_CTRL_CMHS)) return 0; usleep_range(100, 150); } while (ktime_before(ktime_get(), timeout)); return -ETIMEDOUT; } /* * Returns maximum possible rate from capability supporting only DP 2.0 * and below. Used when DP BW allocation mode is not enabled. */ static inline u32 tb_dp_cap_get_rate(u32 val) { u32 rate = (val & DP_COMMON_CAP_RATE_MASK) >> DP_COMMON_CAP_RATE_SHIFT; switch (rate) { case DP_COMMON_CAP_RATE_RBR: return 1620; case DP_COMMON_CAP_RATE_HBR: return 2700; case DP_COMMON_CAP_RATE_HBR2: return 5400; case DP_COMMON_CAP_RATE_HBR3: return 8100; default: return 0; } } /* * Returns maximum possible rate from capability supporting DP 2.1 * UHBR20, 13.5 and 10 rates as well. Use only when DP BW allocation * mode is enabled. */ static inline u32 tb_dp_cap_get_rate_ext(u32 val) { if (val & DP_COMMON_CAP_UHBR20) return 20000; else if (val & DP_COMMON_CAP_UHBR13_5) return 13500; else if (val & DP_COMMON_CAP_UHBR10) return 10000; return tb_dp_cap_get_rate(val); } static inline bool tb_dp_is_uhbr_rate(unsigned int rate) { return rate >= 10000; } static inline u32 tb_dp_cap_set_rate(u32 val, u32 rate) { val &= ~DP_COMMON_CAP_RATE_MASK; switch (rate) { default: WARN(1, "invalid rate %u passed, defaulting to 1620 MB/s\n", rate); fallthrough; case 1620: val |= DP_COMMON_CAP_RATE_RBR << DP_COMMON_CAP_RATE_SHIFT; break; case 2700: val |= DP_COMMON_CAP_RATE_HBR << DP_COMMON_CAP_RATE_SHIFT; break; case 5400: val |= DP_COMMON_CAP_RATE_HBR2 << DP_COMMON_CAP_RATE_SHIFT; break; case 8100: val |= DP_COMMON_CAP_RATE_HBR3 << DP_COMMON_CAP_RATE_SHIFT; break; } return val; } static inline u32 tb_dp_cap_get_lanes(u32 val) { u32 lanes = (val & DP_COMMON_CAP_LANES_MASK) >> DP_COMMON_CAP_LANES_SHIFT; switch (lanes) { case DP_COMMON_CAP_1_LANE: return 1; case DP_COMMON_CAP_2_LANES: return 2; case DP_COMMON_CAP_4_LANES: return 4; default: return 0; } } static inline u32 tb_dp_cap_set_lanes(u32 val, u32 lanes) { val &= ~DP_COMMON_CAP_LANES_MASK; switch (lanes) { default: WARN(1, "invalid number of lanes %u passed, defaulting to 1\n", lanes); fallthrough; case 1: val |= DP_COMMON_CAP_1_LANE << DP_COMMON_CAP_LANES_SHIFT; break; case 2: val |= DP_COMMON_CAP_2_LANES << DP_COMMON_CAP_LANES_SHIFT; break; case 4: val |= DP_COMMON_CAP_4_LANES << DP_COMMON_CAP_LANES_SHIFT; break; } return val; } static unsigned int tb_dp_bandwidth(unsigned int rate, unsigned int lanes) { /* Tunneling removes the DP 8b/10b 128/132b encoding */ if (tb_dp_is_uhbr_rate(rate)) return rate * lanes * 128 / 132; return rate * lanes * 8 / 10; } static int tb_dp_reduce_bandwidth(int max_bw, u32 in_rate, u32 in_lanes, u32 out_rate, u32 out_lanes, u32 *new_rate, u32 *new_lanes) { static const u32 dp_bw[][2] = { /* Mb/s, lanes */ { 8100, 4 }, /* 25920 Mb/s */ { 5400, 4 }, /* 17280 Mb/s */ { 8100, 2 }, /* 12960 Mb/s */ { 2700, 4 }, /* 8640 Mb/s */ { 5400, 2 }, /* 8640 Mb/s */ { 8100, 1 }, /* 6480 Mb/s */ { 1620, 4 }, /* 5184 Mb/s */ { 5400, 1 }, /* 4320 Mb/s */ { 2700, 2 }, /* 4320 Mb/s */ { 1620, 2 }, /* 2592 Mb/s */ { 2700, 1 }, /* 2160 Mb/s */ { 1620, 1 }, /* 1296 Mb/s */ }; unsigned int i; /* * Find a combination that can fit into max_bw and does not * exceed the maximum rate and lanes supported by the DP OUT and * DP IN adapters. */ for (i = 0; i < ARRAY_SIZE(dp_bw); i++) { if (dp_bw[i][0] > out_rate || dp_bw[i][1] > out_lanes) continue; if (dp_bw[i][0] > in_rate || dp_bw[i][1] > in_lanes) continue; if (tb_dp_bandwidth(dp_bw[i][0], dp_bw[i][1]) <= max_bw) { *new_rate = dp_bw[i][0]; *new_lanes = dp_bw[i][1]; return 0; } } return -ENOSR; } static int tb_dp_xchg_caps(struct tb_tunnel *tunnel) { u32 out_dp_cap, out_rate, out_lanes, in_dp_cap, in_rate, in_lanes, bw; struct tb_port *out = tunnel->dst_port; struct tb_port *in = tunnel->src_port; int ret, max_bw; /* * Copy DP_LOCAL_CAP register to DP_REMOTE_CAP register for * newer generation hardware. */ if (in->sw->generation < 2 || out->sw->generation < 2) return 0; /* * Perform connection manager handshake between IN and OUT ports * before capabilities exchange can take place. */ ret = tb_dp_cm_handshake(in, out, 3000); if (ret) return ret; /* Read both DP_LOCAL_CAP registers */ ret = tb_port_read(in, &in_dp_cap, TB_CFG_PORT, in->cap_adap + DP_LOCAL_CAP, 1); if (ret) return ret; ret = tb_port_read(out, &out_dp_cap, TB_CFG_PORT, out->cap_adap + DP_LOCAL_CAP, 1); if (ret) return ret; /* Write IN local caps to OUT remote caps */ ret = tb_port_write(out, &in_dp_cap, TB_CFG_PORT, out->cap_adap + DP_REMOTE_CAP, 1); if (ret) return ret; in_rate = tb_dp_cap_get_rate(in_dp_cap); in_lanes = tb_dp_cap_get_lanes(in_dp_cap); tb_tunnel_dbg(tunnel, "DP IN maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n", in_rate, in_lanes, tb_dp_bandwidth(in_rate, in_lanes)); /* * If the tunnel bandwidth is limited (max_bw is set) then see * if we need to reduce bandwidth to fit there. */ out_rate = tb_dp_cap_get_rate(out_dp_cap); out_lanes = tb_dp_cap_get_lanes(out_dp_cap); bw = tb_dp_bandwidth(out_rate, out_lanes); tb_tunnel_dbg(tunnel, "DP OUT maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n", out_rate, out_lanes, bw); if (tb_port_path_direction_downstream(in, out)) max_bw = tunnel->max_down; else max_bw = tunnel->max_up; if (max_bw && bw > max_bw) { u32 new_rate, new_lanes, new_bw; ret = tb_dp_reduce_bandwidth(max_bw, in_rate, in_lanes, out_rate, out_lanes, &new_rate, &new_lanes); if (ret) { tb_tunnel_info(tunnel, "not enough bandwidth\n"); return ret; } new_bw = tb_dp_bandwidth(new_rate, new_lanes); tb_tunnel_dbg(tunnel, "bandwidth reduced to %u Mb/s x%u = %u Mb/s\n", new_rate, new_lanes, new_bw); /* * Set new rate and number of lanes before writing it to * the IN port remote caps. */ out_dp_cap = tb_dp_cap_set_rate(out_dp_cap, new_rate); out_dp_cap = tb_dp_cap_set_lanes(out_dp_cap, new_lanes); } /* * Titan Ridge does not disable AUX timers when it gets * SET_CONFIG with SET_LTTPR_MODE set. This causes problems with * DP tunneling. */ if (tb_route(out->sw) && tb_switch_is_titan_ridge(out->sw)) { out_dp_cap |= DP_COMMON_CAP_LTTPR_NS; tb_tunnel_dbg(tunnel, "disabling LTTPR\n"); } return tb_port_write(in, &out_dp_cap, TB_CFG_PORT, in->cap_adap + DP_REMOTE_CAP, 1); } static int tb_dp_bandwidth_alloc_mode_enable(struct tb_tunnel *tunnel) { int ret, estimated_bw, granularity, tmp; struct tb_port *out = tunnel->dst_port; struct tb_port *in = tunnel->src_port; u32 out_dp_cap, out_rate, out_lanes; u32 in_dp_cap, in_rate, in_lanes; u32 rate, lanes; if (!bw_alloc_mode) return 0; ret = usb4_dp_port_set_cm_bandwidth_mode_supported(in, true); if (ret) return ret; ret = usb4_dp_port_set_group_id(in, in->group->index); if (ret) return ret; /* * Get the non-reduced rate and lanes based on the lowest * capability of both adapters. */ ret = tb_port_read(in, &in_dp_cap, TB_CFG_PORT, in->cap_adap + DP_LOCAL_CAP, 1); if (ret) return ret; ret = tb_port_read(out, &out_dp_cap, TB_CFG_PORT, out->cap_adap + DP_LOCAL_CAP, 1); if (ret) return ret; in_rate = tb_dp_cap_get_rate(in_dp_cap); in_lanes = tb_dp_cap_get_lanes(in_dp_cap); out_rate = tb_dp_cap_get_rate(out_dp_cap); out_lanes = tb_dp_cap_get_lanes(out_dp_cap); rate = min(in_rate, out_rate); lanes = min(in_lanes, out_lanes); tmp = tb_dp_bandwidth(rate, lanes); tb_tunnel_dbg(tunnel, "non-reduced bandwidth %u Mb/s x%u = %u Mb/s\n", rate, lanes, tmp); ret = usb4_dp_port_set_nrd(in, rate, lanes); if (ret) return ret; /* * Pick up granularity that supports maximum possible bandwidth. * For that we use the UHBR rates too. */ in_rate = tb_dp_cap_get_rate_ext(in_dp_cap); out_rate = tb_dp_cap_get_rate_ext(out_dp_cap); rate = min(in_rate, out_rate); tmp = tb_dp_bandwidth(rate, lanes); tb_tunnel_dbg(tunnel, "maximum bandwidth through allocation mode %u Mb/s x%u = %u Mb/s\n", rate, lanes, tmp); for (granularity = 250; tmp / granularity > 255 && granularity <= 1000; granularity *= 2) ; tb_tunnel_dbg(tunnel, "granularity %d Mb/s\n", granularity); /* * Returns -EINVAL if granularity above is outside of the * accepted ranges. */ ret = usb4_dp_port_set_granularity(in, granularity); if (ret) return ret; /* * Bandwidth estimation is pretty much what we have in * max_up/down fields. For discovery we just read what the * estimation was set to. */ if (tb_port_path_direction_downstream(in, out)) estimated_bw = tunnel->max_down; else estimated_bw = tunnel->max_up; tb_tunnel_dbg(tunnel, "estimated bandwidth %d Mb/s\n", estimated_bw); ret = usb4_dp_port_set_estimated_bandwidth(in, estimated_bw); if (ret) return ret; /* Initial allocation should be 0 according the spec */ ret = usb4_dp_port_allocate_bandwidth(in, 0); if (ret) return ret; tb_tunnel_dbg(tunnel, "bandwidth allocation mode enabled\n"); return 0; } static int tb_dp_init(struct tb_tunnel *tunnel) { struct tb_port *in = tunnel->src_port; struct tb_switch *sw = in->sw; struct tb *tb = in->sw->tb; int ret; ret = tb_dp_xchg_caps(tunnel); if (ret) return ret; if (!tb_switch_is_usb4(sw)) return 0; if (!usb4_dp_port_bandwidth_mode_supported(in)) return 0; tb_tunnel_dbg(tunnel, "bandwidth allocation mode supported\n"); ret = usb4_dp_port_set_cm_id(in, tb->index); if (ret) return ret; return tb_dp_bandwidth_alloc_mode_enable(tunnel); } static void tb_dp_deinit(struct tb_tunnel *tunnel) { struct tb_port *in = tunnel->src_port; if (!usb4_dp_port_bandwidth_mode_supported(in)) return; if (usb4_dp_port_bandwidth_mode_enabled(in)) { usb4_dp_port_set_cm_bandwidth_mode_supported(in, false); tb_tunnel_dbg(tunnel, "bandwidth allocation mode disabled\n"); } } static int tb_dp_activate(struct tb_tunnel *tunnel, bool active) { int ret; if (active) { struct tb_path **paths; int last; paths = tunnel->paths; last = paths[TB_DP_VIDEO_PATH_OUT]->path_length - 1; tb_dp_port_set_hops(tunnel->src_port, paths[TB_DP_VIDEO_PATH_OUT]->hops[0].in_hop_index, paths[TB_DP_AUX_PATH_OUT]->hops[0].in_hop_index, paths[TB_DP_AUX_PATH_IN]->hops[last].next_hop_index); tb_dp_port_set_hops(tunnel->dst_port, paths[TB_DP_VIDEO_PATH_OUT]->hops[last].next_hop_index, paths[TB_DP_AUX_PATH_IN]->hops[0].in_hop_index, paths[TB_DP_AUX_PATH_OUT]->hops[last].next_hop_index); } else { tb_dp_port_hpd_clear(tunnel->src_port); tb_dp_port_set_hops(tunnel->src_port, 0, 0, 0); if (tb_port_is_dpout(tunnel->dst_port)) tb_dp_port_set_hops(tunnel->dst_port, 0, 0, 0); } ret = tb_dp_port_enable(tunnel->src_port, active); if (ret) return ret; if (tb_port_is_dpout(tunnel->dst_port)) return tb_dp_port_enable(tunnel->dst_port, active); return 0; } /* max_bw is rounded up to next granularity */ static int tb_dp_bandwidth_mode_maximum_bandwidth(struct tb_tunnel *tunnel, int *max_bw) { struct tb_port *in = tunnel->src_port; int ret, rate, lanes, nrd_bw; u32 cap; /* * DP IN adapter DP_LOCAL_CAP gets updated to the lowest AUX * read parameter values so this so we can use this to determine * the maximum possible bandwidth over this link. * * See USB4 v2 spec 1.0 10.4.4.5. */ ret = tb_port_read(in, &cap, TB_CFG_PORT, in->cap_adap + DP_LOCAL_CAP, 1); if (ret) return ret; rate = tb_dp_cap_get_rate_ext(cap); if (tb_dp_is_uhbr_rate(rate)) { /* * When UHBR is used there is no reduction in lanes so * we can use this directly. */ lanes = tb_dp_cap_get_lanes(cap); } else { /* * If there is no UHBR supported then check the * non-reduced rate and lanes. */ ret = usb4_dp_port_nrd(in, &rate, &lanes); if (ret) return ret; } nrd_bw = tb_dp_bandwidth(rate, lanes); if (max_bw) { ret = usb4_dp_port_granularity(in); if (ret < 0) return ret; *max_bw = roundup(nrd_bw, ret); } return nrd_bw; } static int tb_dp_bandwidth_mode_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up, int *consumed_down) { struct tb_port *out = tunnel->dst_port; struct tb_port *in = tunnel->src_port; int ret, allocated_bw, max_bw; if (!usb4_dp_port_bandwidth_mode_enabled(in)) return -EOPNOTSUPP; if (!tunnel->bw_mode) return -EOPNOTSUPP; /* Read what was allocated previously if any */ ret = usb4_dp_port_allocated_bandwidth(in); if (ret < 0) return ret; allocated_bw = ret; ret = tb_dp_bandwidth_mode_maximum_bandwidth(tunnel, &max_bw); if (ret < 0) return ret; if (allocated_bw == max_bw) allocated_bw = ret; if (tb_port_path_direction_downstream(in, out)) { *consumed_up = 0; *consumed_down = allocated_bw; } else { *consumed_up = allocated_bw; *consumed_down = 0; } return 0; } static int tb_dp_allocated_bandwidth(struct tb_tunnel *tunnel, int *allocated_up, int *allocated_down) { struct tb_port *out = tunnel->dst_port; struct tb_port *in = tunnel->src_port; /* * If we have already set the allocated bandwidth then use that. * Otherwise we read it from the DPRX. */ if (usb4_dp_port_bandwidth_mode_enabled(in) && tunnel->bw_mode) { int ret, allocated_bw, max_bw; ret = usb4_dp_port_allocated_bandwidth(in); if (ret < 0) return ret; allocated_bw = ret; ret = tb_dp_bandwidth_mode_maximum_bandwidth(tunnel, &max_bw); if (ret < 0) return ret; if (allocated_bw == max_bw) allocated_bw = ret; if (tb_port_path_direction_downstream(in, out)) { *allocated_up = 0; *allocated_down = allocated_bw; } else { *allocated_up = allocated_bw; *allocated_down = 0; } return 0; } return tunnel->consumed_bandwidth(tunnel, allocated_up, allocated_down); } static int tb_dp_alloc_bandwidth(struct tb_tunnel *tunnel, int *alloc_up, int *alloc_down) { struct tb_port *out = tunnel->dst_port; struct tb_port *in = tunnel->src_port; int max_bw, ret, tmp; if (!usb4_dp_port_bandwidth_mode_enabled(in)) return -EOPNOTSUPP; ret = tb_dp_bandwidth_mode_maximum_bandwidth(tunnel, &max_bw); if (ret < 0) return ret; if (tb_port_path_direction_downstream(in, out)) { tmp = min(*alloc_down, max_bw); ret = usb4_dp_port_allocate_bandwidth(in, tmp); if (ret) return ret; *alloc_down = tmp; *alloc_up = 0; } else { tmp = min(*alloc_up, max_bw); ret = usb4_dp_port_allocate_bandwidth(in, tmp); if (ret) return ret; *alloc_down = 0; *alloc_up = tmp; } /* Now we can use BW mode registers to figure out the bandwidth */ /* TODO: need to handle discovery too */ tunnel->bw_mode = true; return 0; } static int tb_dp_wait_dprx(struct tb_tunnel *tunnel, int timeout_msec) { ktime_t timeout = ktime_add_ms(ktime_get(), timeout_msec); struct tb_port *in = tunnel->src_port; /* * Wait for DPRX done. Normally it should be already set for * active tunnel. */ do { u32 val; int ret; ret = tb_port_read(in, &val, TB_CFG_PORT, in->cap_adap + DP_COMMON_CAP, 1); if (ret) return ret; if (val & DP_COMMON_CAP_DPRX_DONE) { tb_tunnel_dbg(tunnel, "DPRX read done\n"); return 0; } usleep_range(100, 150); } while (ktime_before(ktime_get(), timeout)); tb_tunnel_dbg(tunnel, "DPRX read timeout\n"); return -ETIMEDOUT; } /* Read cap from tunnel DP IN */ static int tb_dp_read_cap(struct tb_tunnel *tunnel, unsigned int cap, u32 *rate, u32 *lanes) { struct tb_port *in = tunnel->src_port; u32 val; int ret; switch (cap) { case DP_LOCAL_CAP: case DP_REMOTE_CAP: case DP_COMMON_CAP: break; default: tb_tunnel_WARN(tunnel, "invalid capability index %#x\n", cap); return -EINVAL; } /* * Read from the copied remote cap so that we take into account * if capabilities were reduced during exchange. */ ret = tb_port_read(in, &val, TB_CFG_PORT, in->cap_adap + cap, 1); if (ret) return ret; *rate = tb_dp_cap_get_rate(val); *lanes = tb_dp_cap_get_lanes(val); return 0; } static int tb_dp_maximum_bandwidth(struct tb_tunnel *tunnel, int *max_up, int *max_down) { struct tb_port *in = tunnel->src_port; int ret; if (!usb4_dp_port_bandwidth_mode_enabled(in)) return -EOPNOTSUPP; ret = tb_dp_bandwidth_mode_maximum_bandwidth(tunnel, NULL); if (ret < 0) return ret; if (tb_port_path_direction_downstream(in, tunnel->dst_port)) { *max_up = 0; *max_down = ret; } else { *max_up = ret; *max_down = 0; } return 0; } static int tb_dp_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up, int *consumed_down) { struct tb_port *in = tunnel->src_port; const struct tb_switch *sw = in->sw; u32 rate = 0, lanes = 0; int ret; if (tb_dp_is_usb4(sw)) { /* * On USB4 routers check if the bandwidth allocation * mode is enabled first and then read the bandwidth * through those registers. */ ret = tb_dp_bandwidth_mode_consumed_bandwidth(tunnel, consumed_up, consumed_down); if (ret < 0) { if (ret != -EOPNOTSUPP) return ret; } else if (!ret) { return 0; } /* * Then see if the DPRX negotiation is ready and if yes * return that bandwidth (it may be smaller than the * reduced one). According to VESA spec, the DPRX * negotiation shall compete in 5 seconds after tunnel * established. We give it 100ms extra just in case. */ ret = tb_dp_wait_dprx(tunnel, 5100); if (ret) return ret; ret = tb_dp_read_cap(tunnel, DP_COMMON_CAP, &rate, &lanes); if (ret) return ret; } else if (sw->generation >= 2) { ret = tb_dp_read_cap(tunnel, DP_REMOTE_CAP, &rate, &lanes); if (ret) return ret; } else { /* No bandwidth management for legacy devices */ *consumed_up = 0; *consumed_down = 0; return 0; } if (tb_port_path_direction_downstream(in, tunnel->dst_port)) { *consumed_up = 0; *consumed_down = tb_dp_bandwidth(rate, lanes); } else { *consumed_up = tb_dp_bandwidth(rate, lanes); *consumed_down = 0; } return 0; } static void tb_dp_init_aux_credits(struct tb_path_hop *hop) { struct tb_port *port = hop->in_port; struct tb_switch *sw = port->sw; if (tb_port_use_credit_allocation(port)) hop->initial_credits = sw->min_dp_aux_credits; else hop->initial_credits = 1; } static void tb_dp_init_aux_path(struct tb_path *path, bool pm_support) { struct tb_path_hop *hop; path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL; path->egress_shared_buffer = TB_PATH_NONE; path->ingress_fc_enable = TB_PATH_ALL; path->ingress_shared_buffer = TB_PATH_NONE; path->priority = TB_DP_AUX_PRIORITY; path->weight = TB_DP_AUX_WEIGHT; tb_path_for_each_hop(path, hop) { tb_dp_init_aux_credits(hop); if (pm_support) tb_init_pm_support(hop); } } static int tb_dp_init_video_credits(struct tb_path_hop *hop) { struct tb_port *port = hop->in_port; struct tb_switch *sw = port->sw; if (tb_port_use_credit_allocation(port)) { unsigned int nfc_credits; size_t max_dp_streams; tb_available_credits(port, &max_dp_streams); /* * Read the number of currently allocated NFC credits * from the lane adapter. Since we only use them for DP * tunneling we can use that to figure out how many DP * tunnels already go through the lane adapter. */ nfc_credits = port->config.nfc_credits & ADP_CS_4_NFC_BUFFERS_MASK; if (nfc_credits / sw->min_dp_main_credits > max_dp_streams) return -ENOSPC; hop->nfc_credits = sw->min_dp_main_credits; } else { hop->nfc_credits = min(port->total_credits - 2, 12U); } return 0; } static int tb_dp_init_video_path(struct tb_path *path, bool pm_support) { struct tb_path_hop *hop; path->egress_fc_enable = TB_PATH_NONE; path->egress_shared_buffer = TB_PATH_NONE; path->ingress_fc_enable = TB_PATH_NONE; path->ingress_shared_buffer = TB_PATH_NONE; path->priority = TB_DP_VIDEO_PRIORITY; path->weight = TB_DP_VIDEO_WEIGHT; tb_path_for_each_hop(path, hop) { int ret; ret = tb_dp_init_video_credits(hop); if (ret) return ret; if (pm_support) tb_init_pm_support(hop); } return 0; } static void tb_dp_dump(struct tb_tunnel *tunnel) { struct tb_port *in, *out; u32 dp_cap, rate, lanes; in = tunnel->src_port; out = tunnel->dst_port; if (tb_port_read(in, &dp_cap, TB_CFG_PORT, in->cap_adap + DP_LOCAL_CAP, 1)) return; rate = tb_dp_cap_get_rate(dp_cap); lanes = tb_dp_cap_get_lanes(dp_cap); tb_tunnel_dbg(tunnel, "DP IN maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n", rate, lanes, tb_dp_bandwidth(rate, lanes)); if (tb_port_read(out, &dp_cap, TB_CFG_PORT, out->cap_adap + DP_LOCAL_CAP, 1)) return; rate = tb_dp_cap_get_rate(dp_cap); lanes = tb_dp_cap_get_lanes(dp_cap); tb_tunnel_dbg(tunnel, "DP OUT maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n", rate, lanes, tb_dp_bandwidth(rate, lanes)); if (tb_port_read(in, &dp_cap, TB_CFG_PORT, in->cap_adap + DP_REMOTE_CAP, 1)) return; rate = tb_dp_cap_get_rate(dp_cap); lanes = tb_dp_cap_get_lanes(dp_cap); tb_tunnel_dbg(tunnel, "reduced bandwidth %u Mb/s x%u = %u Mb/s\n", rate, lanes, tb_dp_bandwidth(rate, lanes)); } /** * tb_tunnel_discover_dp() - Discover existing Display Port tunnels * @tb: Pointer to the domain structure * @in: DP in adapter * @alloc_hopid: Allocate HopIDs from visited ports * * If @in adapter is active, follows the tunnel to the DP out adapter * and back. Returns the discovered tunnel or %NULL if there was no * tunnel. * * Return: DP tunnel or %NULL if no tunnel found. */ struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in, bool alloc_hopid) { struct tb_tunnel *tunnel; struct tb_port *port; struct tb_path *path; if (!tb_dp_port_is_enabled(in)) return NULL; tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP); if (!tunnel) return NULL; tunnel->init = tb_dp_init; tunnel->deinit = tb_dp_deinit; tunnel->activate = tb_dp_activate; tunnel->maximum_bandwidth = tb_dp_maximum_bandwidth; tunnel->allocated_bandwidth = tb_dp_allocated_bandwidth; tunnel->alloc_bandwidth = tb_dp_alloc_bandwidth; tunnel->consumed_bandwidth = tb_dp_consumed_bandwidth; tunnel->src_port = in; path = tb_path_discover(in, TB_DP_VIDEO_HOPID, NULL, -1, &tunnel->dst_port, "Video", alloc_hopid); if (!path) { /* Just disable the DP IN port */ tb_dp_port_enable(in, false); goto err_free; } tunnel->paths[TB_DP_VIDEO_PATH_OUT] = path; if (tb_dp_init_video_path(tunnel->paths[TB_DP_VIDEO_PATH_OUT], false)) goto err_free; path = tb_path_discover(in, TB_DP_AUX_TX_HOPID, NULL, -1, NULL, "AUX TX", alloc_hopid); if (!path) goto err_deactivate; tunnel->paths[TB_DP_AUX_PATH_OUT] = path; tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_OUT], false); path = tb_path_discover(tunnel->dst_port, -1, in, TB_DP_AUX_RX_HOPID, &port, "AUX RX", alloc_hopid); if (!path) goto err_deactivate; tunnel->paths[TB_DP_AUX_PATH_IN] = path; tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_IN], false); /* Validate that the tunnel is complete */ if (!tb_port_is_dpout(tunnel->dst_port)) { tb_port_warn(in, "path does not end on a DP adapter, cleaning up\n"); goto err_deactivate; } if (!tb_dp_port_is_enabled(tunnel->dst_port)) goto err_deactivate; if (!tb_dp_port_hpd_is_active(tunnel->dst_port)) goto err_deactivate; if (port != tunnel->src_port) { tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n"); goto err_deactivate; } tb_dp_dump(tunnel); tb_tunnel_dbg(tunnel, "discovered\n"); return tunnel; err_deactivate: tb_tunnel_deactivate(tunnel); err_free: tb_tunnel_free(tunnel); return NULL; } /** * tb_tunnel_alloc_dp() - allocate a Display Port tunnel * @tb: Pointer to the domain structure * @in: DP in adapter port * @out: DP out adapter port * @link_nr: Preferred lane adapter when the link is not bonded * @max_up: Maximum available upstream bandwidth for the DP tunnel (%0 * if not limited) * @max_down: Maximum available downstream bandwidth for the DP tunnel * (%0 if not limited) * * Allocates a tunnel between @in and @out that is capable of tunneling * Display Port traffic. * * Return: Returns a tb_tunnel on success or NULL on failure. */ struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in, struct tb_port *out, int link_nr, int max_up, int max_down) { struct tb_tunnel *tunnel; struct tb_path **paths; struct tb_path *path; bool pm_support; if (WARN_ON(!in->cap_adap || !out->cap_adap)) return NULL; tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP); if (!tunnel) return NULL; tunnel->init = tb_dp_init; tunnel->deinit = tb_dp_deinit; tunnel->activate = tb_dp_activate; tunnel->maximum_bandwidth = tb_dp_maximum_bandwidth; tunnel->allocated_bandwidth = tb_dp_allocated_bandwidth; tunnel->alloc_bandwidth = tb_dp_alloc_bandwidth; tunnel->consumed_bandwidth = tb_dp_consumed_bandwidth; tunnel->src_port = in; tunnel->dst_port = out; tunnel->max_up = max_up; tunnel->max_down = max_down; paths = tunnel->paths; pm_support = usb4_switch_version(in->sw) >= 2; path = tb_path_alloc(tb, in, TB_DP_VIDEO_HOPID, out, TB_DP_VIDEO_HOPID, link_nr, "Video"); if (!path) goto err_free; tb_dp_init_video_path(path, pm_support); paths[TB_DP_VIDEO_PATH_OUT] = path; path = tb_path_alloc(tb, in, TB_DP_AUX_TX_HOPID, out, TB_DP_AUX_TX_HOPID, link_nr, "AUX TX"); if (!path) goto err_free; tb_dp_init_aux_path(path, pm_support); paths[TB_DP_AUX_PATH_OUT] = path; path = tb_path_alloc(tb, out, TB_DP_AUX_RX_HOPID, in, TB_DP_AUX_RX_HOPID, link_nr, "AUX RX"); if (!path) goto err_free; tb_dp_init_aux_path(path, pm_support); paths[TB_DP_AUX_PATH_IN] = path; return tunnel; err_free: tb_tunnel_free(tunnel); return NULL; } static unsigned int tb_dma_available_credits(const struct tb_port *port) { const struct tb_switch *sw = port->sw; int credits; credits = tb_available_credits(port, NULL); if (tb_acpi_may_tunnel_pcie()) credits -= sw->max_pcie_credits; credits -= port->dma_credits; return credits > 0 ? credits : 0; } static int tb_dma_reserve_credits(struct tb_path_hop *hop, unsigned int credits) { struct tb_port *port = hop->in_port; if (tb_port_use_credit_allocation(port)) { unsigned int available = tb_dma_available_credits(port); /* * Need to have at least TB_MIN_DMA_CREDITS, otherwise * DMA path cannot be established. */ if (available < TB_MIN_DMA_CREDITS) return -ENOSPC; while (credits > available) credits--; tb_port_dbg(port, "reserving %u credits for DMA path\n", credits); port->dma_credits += credits; } else { if (tb_port_is_null(port)) credits = port->bonded ? 14 : 6; else credits = min(port->total_credits, credits); } hop->initial_credits = credits; return 0; } /* Path from lane adapter to NHI */ static int tb_dma_init_rx_path(struct tb_path *path, unsigned int credits) { struct tb_path_hop *hop; unsigned int i, tmp; path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL; path->ingress_fc_enable = TB_PATH_ALL; path->egress_shared_buffer = TB_PATH_NONE; path->ingress_shared_buffer = TB_PATH_NONE; path->priority = TB_DMA_PRIORITY; path->weight = TB_DMA_WEIGHT; path->clear_fc = true; /* * First lane adapter is the one connected to the remote host. * We don't tunnel other traffic over this link so can use all * the credits (except the ones reserved for control traffic). */ hop = &path->hops[0]; tmp = min(tb_usable_credits(hop->in_port), credits); hop->initial_credits = tmp; hop->in_port->dma_credits += tmp; for (i = 1; i < path->path_length; i++) { int ret; ret = tb_dma_reserve_credits(&path->hops[i], credits); if (ret) return ret; } return 0; } /* Path from NHI to lane adapter */ static int tb_dma_init_tx_path(struct tb_path *path, unsigned int credits) { struct tb_path_hop *hop; path->egress_fc_enable = TB_PATH_ALL; path->ingress_fc_enable = TB_PATH_ALL; path->egress_shared_buffer = TB_PATH_NONE; path->ingress_shared_buffer = TB_PATH_NONE; path->priority = TB_DMA_PRIORITY; path->weight = TB_DMA_WEIGHT; path->clear_fc = true; tb_path_for_each_hop(path, hop) { int ret; ret = tb_dma_reserve_credits(hop, credits); if (ret) return ret; } return 0; } static void tb_dma_release_credits(struct tb_path_hop *hop) { struct tb_port *port = hop->in_port; if (tb_port_use_credit_allocation(port)) { port->dma_credits -= hop->initial_credits; tb_port_dbg(port, "released %u DMA path credits\n", hop->initial_credits); } } static void tb_dma_deinit_path(struct tb_path *path) { struct tb_path_hop *hop; tb_path_for_each_hop(path, hop) tb_dma_release_credits(hop); } static void tb_dma_deinit(struct tb_tunnel *tunnel) { int i; for (i = 0; i < tunnel->npaths; i++) { if (!tunnel->paths[i]) continue; tb_dma_deinit_path(tunnel->paths[i]); } } /** * tb_tunnel_alloc_dma() - allocate a DMA tunnel * @tb: Pointer to the domain structure * @nhi: Host controller port * @dst: Destination null port which the other domain is connected to * @transmit_path: HopID used for transmitting packets * @transmit_ring: NHI ring number used to send packets towards the * other domain. Set to %-1 if TX path is not needed. * @receive_path: HopID used for receiving packets * @receive_ring: NHI ring number used to receive packets from the * other domain. Set to %-1 if RX path is not needed. * * Return: Returns a tb_tunnel on success or NULL on failure. */ struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi, struct tb_port *dst, int transmit_path, int transmit_ring, int receive_path, int receive_ring) { struct tb_tunnel *tunnel; size_t npaths = 0, i = 0; struct tb_path *path; int credits; /* Ring 0 is reserved for control channel */ if (WARN_ON(!receive_ring || !transmit_ring)) return NULL; if (receive_ring > 0) npaths++; if (transmit_ring > 0) npaths++; if (WARN_ON(!npaths)) return NULL; tunnel = tb_tunnel_alloc(tb, npaths, TB_TUNNEL_DMA); if (!tunnel) return NULL; tunnel->src_port = nhi; tunnel->dst_port = dst; tunnel->deinit = tb_dma_deinit; credits = min_not_zero(dma_credits, nhi->sw->max_dma_credits); if (receive_ring > 0) { path = tb_path_alloc(tb, dst, receive_path, nhi, receive_ring, 0, "DMA RX"); if (!path) goto err_free; tunnel->paths[i++] = path; if (tb_dma_init_rx_path(path, credits)) { tb_tunnel_dbg(tunnel, "not enough buffers for RX path\n"); goto err_free; } } if (transmit_ring > 0) { path = tb_path_alloc(tb, nhi, transmit_ring, dst, transmit_path, 0, "DMA TX"); if (!path) goto err_free; tunnel->paths[i++] = path; if (tb_dma_init_tx_path(path, credits)) { tb_tunnel_dbg(tunnel, "not enough buffers for TX path\n"); goto err_free; } } return tunnel; err_free: tb_tunnel_free(tunnel); return NULL; } /** * tb_tunnel_match_dma() - Match DMA tunnel * @tunnel: Tunnel to match * @transmit_path: HopID used for transmitting packets. Pass %-1 to ignore. * @transmit_ring: NHI ring number used to send packets towards the * other domain. Pass %-1 to ignore. * @receive_path: HopID used for receiving packets. Pass %-1 to ignore. * @receive_ring: NHI ring number used to receive packets from the * other domain. Pass %-1 to ignore. * * This function can be used to match specific DMA tunnel, if there are * multiple DMA tunnels going through the same XDomain connection. * Returns true if there is match and false otherwise. */ bool tb_tunnel_match_dma(const struct tb_tunnel *tunnel, int transmit_path, int transmit_ring, int receive_path, int receive_ring) { const struct tb_path *tx_path = NULL, *rx_path = NULL; int i; if (!receive_ring || !transmit_ring) return false; for (i = 0; i < tunnel->npaths; i++) { const struct tb_path *path = tunnel->paths[i]; if (!path) continue; if (tb_port_is_nhi(path->hops[0].in_port)) tx_path = path; else if (tb_port_is_nhi(path->hops[path->path_length - 1].out_port)) rx_path = path; } if (transmit_ring > 0 || transmit_path > 0) { if (!tx_path) return false; if (transmit_ring > 0 && (tx_path->hops[0].in_hop_index != transmit_ring)) return false; if (transmit_path > 0 && (tx_path->hops[tx_path->path_length - 1].next_hop_index != transmit_path)) return false; } if (receive_ring > 0 || receive_path > 0) { if (!rx_path) return false; if (receive_path > 0 && (rx_path->hops[0].in_hop_index != receive_path)) return false; if (receive_ring > 0 && (rx_path->hops[rx_path->path_length - 1].next_hop_index != receive_ring)) return false; } return true; } static int tb_usb3_max_link_rate(struct tb_port *up, struct tb_port *down) { int ret, up_max_rate, down_max_rate; ret = usb4_usb3_port_max_link_rate(up); if (ret < 0) return ret; up_max_rate = ret; ret = usb4_usb3_port_max_link_rate(down); if (ret < 0) return ret; down_max_rate = ret; return min(up_max_rate, down_max_rate); } static int tb_usb3_init(struct tb_tunnel *tunnel) { tb_tunnel_dbg(tunnel, "allocating initial bandwidth %d/%d Mb/s\n", tunnel->allocated_up, tunnel->allocated_down); return usb4_usb3_port_allocate_bandwidth(tunnel->src_port, &tunnel->allocated_up, &tunnel->allocated_down); } static int tb_usb3_activate(struct tb_tunnel *tunnel, bool activate) { int res; res = tb_usb3_port_enable(tunnel->src_port, activate); if (res) return res; if (tb_port_is_usb3_up(tunnel->dst_port)) return tb_usb3_port_enable(tunnel->dst_port, activate); return 0; } static int tb_usb3_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up, int *consumed_down) { struct tb_port *port = tb_upstream_port(tunnel->dst_port->sw); int pcie_weight = tb_acpi_may_tunnel_pcie() ? TB_PCI_WEIGHT : 0; /* * PCIe tunneling, if enabled, affects the USB3 bandwidth so * take that it into account here. */ *consumed_up = tunnel->allocated_up * (TB_USB3_WEIGHT + pcie_weight) / TB_USB3_WEIGHT; *consumed_down = tunnel->allocated_down * (TB_USB3_WEIGHT + pcie_weight) / TB_USB3_WEIGHT; if (tb_port_get_link_generation(port) >= 4) { *consumed_up = max(*consumed_up, USB4_V2_USB3_MIN_BANDWIDTH); *consumed_down = max(*consumed_down, USB4_V2_USB3_MIN_BANDWIDTH); } return 0; } static int tb_usb3_release_unused_bandwidth(struct tb_tunnel *tunnel) { int ret; ret = usb4_usb3_port_release_bandwidth(tunnel->src_port, &tunnel->allocated_up, &tunnel->allocated_down); if (ret) return ret; tb_tunnel_dbg(tunnel, "decreased bandwidth allocation to %d/%d Mb/s\n", tunnel->allocated_up, tunnel->allocated_down); return 0; } static void tb_usb3_reclaim_available_bandwidth(struct tb_tunnel *tunnel, int *available_up, int *available_down) { int ret, max_rate, allocate_up, allocate_down; ret = tb_usb3_max_link_rate(tunnel->dst_port, tunnel->src_port); if (ret < 0) { tb_tunnel_warn(tunnel, "failed to read maximum link rate\n"); return; } /* * 90% of the max rate can be allocated for isochronous * transfers. */ max_rate = ret * 90 / 100; /* No need to reclaim if already at maximum */ if (tunnel->allocated_up >= max_rate && tunnel->allocated_down >= max_rate) return; /* Don't go lower than what is already allocated */ allocate_up = min(max_rate, *available_up); if (allocate_up < tunnel->allocated_up) allocate_up = tunnel->allocated_up; allocate_down = min(max_rate, *available_down); if (allocate_down < tunnel->allocated_down) allocate_down = tunnel->allocated_down; /* If no changes no need to do more */ if (allocate_up == tunnel->allocated_up && allocate_down == tunnel->allocated_down) return; ret = usb4_usb3_port_allocate_bandwidth(tunnel->src_port, &allocate_up, &allocate_down); if (ret) { tb_tunnel_info(tunnel, "failed to allocate bandwidth\n"); return; } tunnel->allocated_up = allocate_up; *available_up -= tunnel->allocated_up; tunnel->allocated_down = allocate_down; *available_down -= tunnel->allocated_down; tb_tunnel_dbg(tunnel, "increased bandwidth allocation to %d/%d Mb/s\n", tunnel->allocated_up, tunnel->allocated_down); } static void tb_usb3_init_credits(struct tb_path_hop *hop) { struct tb_port *port = hop->in_port; struct tb_switch *sw = port->sw; unsigned int credits; if (tb_port_use_credit_allocation(port)) { credits = sw->max_usb3_credits; } else { if (tb_port_is_null(port)) credits = port->bonded ? 32 : 16; else credits = 7; } hop->initial_credits = credits; } static void tb_usb3_init_path(struct tb_path *path) { struct tb_path_hop *hop; path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL; path->egress_shared_buffer = TB_PATH_NONE; path->ingress_fc_enable = TB_PATH_ALL; path->ingress_shared_buffer = TB_PATH_NONE; path->priority = TB_USB3_PRIORITY; path->weight = TB_USB3_WEIGHT; path->drop_packages = 0; tb_path_for_each_hop(path, hop) tb_usb3_init_credits(hop); } /** * tb_tunnel_discover_usb3() - Discover existing USB3 tunnels * @tb: Pointer to the domain structure * @down: USB3 downstream adapter * @alloc_hopid: Allocate HopIDs from visited ports * * If @down adapter is active, follows the tunnel to the USB3 upstream * adapter and back. Returns the discovered tunnel or %NULL if there was * no tunnel. */ struct tb_tunnel *tb_tunnel_discover_usb3(struct tb *tb, struct tb_port *down, bool alloc_hopid) { struct tb_tunnel *tunnel; struct tb_path *path; if (!tb_usb3_port_is_enabled(down)) return NULL; tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_USB3); if (!tunnel) return NULL; tunnel->activate = tb_usb3_activate; tunnel->src_port = down; /* * Discover both paths even if they are not complete. We will * clean them up by calling tb_tunnel_deactivate() below in that * case. */ path = tb_path_discover(down, TB_USB3_HOPID, NULL, -1, &tunnel->dst_port, "USB3 Down", alloc_hopid); if (!path) { /* Just disable the downstream port */ tb_usb3_port_enable(down, false); goto err_free; } tunnel->paths[TB_USB3_PATH_DOWN] = path; tb_usb3_init_path(tunnel->paths[TB_USB3_PATH_DOWN]); path = tb_path_discover(tunnel->dst_port, -1, down, TB_USB3_HOPID, NULL, "USB3 Up", alloc_hopid); if (!path) goto err_deactivate; tunnel->paths[TB_USB3_PATH_UP] = path; tb_usb3_init_path(tunnel->paths[TB_USB3_PATH_UP]); /* Validate that the tunnel is complete */ if (!tb_port_is_usb3_up(tunnel->dst_port)) { tb_port_warn(tunnel->dst_port, "path does not end on an USB3 adapter, cleaning up\n"); goto err_deactivate; } if (down != tunnel->src_port) { tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n"); goto err_deactivate; } if (!tb_usb3_port_is_enabled(tunnel->dst_port)) { tb_tunnel_warn(tunnel, "tunnel is not fully activated, cleaning up\n"); goto err_deactivate; } if (!tb_route(down->sw)) { int ret; /* * Read the initial bandwidth allocation for the first * hop tunnel. */ ret = usb4_usb3_port_allocated_bandwidth(down, &tunnel->allocated_up, &tunnel->allocated_down); if (ret) goto err_deactivate; tb_tunnel_dbg(tunnel, "currently allocated bandwidth %d/%d Mb/s\n", tunnel->allocated_up, tunnel->allocated_down); tunnel->init = tb_usb3_init; tunnel->consumed_bandwidth = tb_usb3_consumed_bandwidth; tunnel->release_unused_bandwidth = tb_usb3_release_unused_bandwidth; tunnel->reclaim_available_bandwidth = tb_usb3_reclaim_available_bandwidth; } tb_tunnel_dbg(tunnel, "discovered\n"); return tunnel; err_deactivate: tb_tunnel_deactivate(tunnel); err_free: tb_tunnel_free(tunnel); return NULL; } /** * tb_tunnel_alloc_usb3() - allocate a USB3 tunnel * @tb: Pointer to the domain structure * @up: USB3 upstream adapter port * @down: USB3 downstream adapter port * @max_up: Maximum available upstream bandwidth for the USB3 tunnel (%0 * if not limited). * @max_down: Maximum available downstream bandwidth for the USB3 tunnel * (%0 if not limited). * * Allocate an USB3 tunnel. The ports must be of type @TB_TYPE_USB3_UP and * @TB_TYPE_USB3_DOWN. * * Return: Returns a tb_tunnel on success or %NULL on failure. */ struct tb_tunnel *tb_tunnel_alloc_usb3(struct tb *tb, struct tb_port *up, struct tb_port *down, int max_up, int max_down) { struct tb_tunnel *tunnel; struct tb_path *path; int max_rate = 0; /* * Check that we have enough bandwidth available for the new * USB3 tunnel. */ if (max_up > 0 || max_down > 0) { max_rate = tb_usb3_max_link_rate(down, up); if (max_rate < 0) return NULL; /* Only 90% can be allocated for USB3 isochronous transfers */ max_rate = max_rate * 90 / 100; tb_port_dbg(up, "required bandwidth for USB3 tunnel %d Mb/s\n", max_rate); if (max_rate > max_up || max_rate > max_down) { tb_port_warn(up, "not enough bandwidth for USB3 tunnel\n"); return NULL; } } tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_USB3); if (!tunnel) return NULL; tunnel->activate = tb_usb3_activate; tunnel->src_port = down; tunnel->dst_port = up; tunnel->max_up = max_up; tunnel->max_down = max_down; path = tb_path_alloc(tb, down, TB_USB3_HOPID, up, TB_USB3_HOPID, 0, "USB3 Down"); if (!path) { tb_tunnel_free(tunnel); return NULL; } tb_usb3_init_path(path); tunnel->paths[TB_USB3_PATH_DOWN] = path; path = tb_path_alloc(tb, up, TB_USB3_HOPID, down, TB_USB3_HOPID, 0, "USB3 Up"); if (!path) { tb_tunnel_free(tunnel); return NULL; } tb_usb3_init_path(path); tunnel->paths[TB_USB3_PATH_UP] = path; if (!tb_route(down->sw)) { tunnel->allocated_up = max_rate; tunnel->allocated_down = max_rate; tunnel->init = tb_usb3_init; tunnel->consumed_bandwidth = tb_usb3_consumed_bandwidth; tunnel->release_unused_bandwidth = tb_usb3_release_unused_bandwidth; tunnel->reclaim_available_bandwidth = tb_usb3_reclaim_available_bandwidth; } return tunnel; } /** * tb_tunnel_free() - free a tunnel * @tunnel: Tunnel to be freed * * Frees a tunnel. The tunnel does not need to be deactivated. */ void tb_tunnel_free(struct tb_tunnel *tunnel) { int i; if (!tunnel) return; if (tunnel->deinit) tunnel->deinit(tunnel); for (i = 0; i < tunnel->npaths; i++) { if (tunnel->paths[i]) tb_path_free(tunnel->paths[i]); } kfree(tunnel->paths); kfree(tunnel); } /** * tb_tunnel_is_invalid - check whether an activated path is still valid * @tunnel: Tunnel to check */ bool tb_tunnel_is_invalid(struct tb_tunnel *tunnel) { int i; for (i = 0; i < tunnel->npaths; i++) { WARN_ON(!tunnel->paths[i]->activated); if (tb_path_is_invalid(tunnel->paths[i])) return true; } return false; } /** * tb_tunnel_restart() - activate a tunnel after a hardware reset * @tunnel: Tunnel to restart * * Return: 0 on success and negative errno in case if failure */ int tb_tunnel_restart(struct tb_tunnel *tunnel) { int res, i; tb_tunnel_dbg(tunnel, "activating\n"); /* * Make sure all paths are properly disabled before enabling * them again. */ for (i = 0; i < tunnel->npaths; i++) { if (tunnel->paths[i]->activated) { tb_path_deactivate(tunnel->paths[i]); tunnel->paths[i]->activated = false; } } if (tunnel->init) { res = tunnel->init(tunnel); if (res) return res; } for (i = 0; i < tunnel->npaths; i++) { res = tb_path_activate(tunnel->paths[i]); if (res) goto err; } if (tunnel->activate) { res = tunnel->activate(tunnel, true); if (res) goto err; } return 0; err: tb_tunnel_warn(tunnel, "activation failed\n"); tb_tunnel_deactivate(tunnel); return res; } /** * tb_tunnel_activate() - activate a tunnel * @tunnel: Tunnel to activate * * Return: Returns 0 on success or an error code on failure. */ int tb_tunnel_activate(struct tb_tunnel *tunnel) { int i; for (i = 0; i < tunnel->npaths; i++) { if (tunnel->paths[i]->activated) { tb_tunnel_WARN(tunnel, "trying to activate an already activated tunnel\n"); return -EINVAL; } } return tb_tunnel_restart(tunnel); } /** * tb_tunnel_deactivate() - deactivate a tunnel * @tunnel: Tunnel to deactivate */ void tb_tunnel_deactivate(struct tb_tunnel *tunnel) { int i; tb_tunnel_dbg(tunnel, "deactivating\n"); if (tunnel->activate) tunnel->activate(tunnel, false); for (i = 0; i < tunnel->npaths; i++) { if (tunnel->paths[i] && tunnel->paths[i]->activated) tb_path_deactivate(tunnel->paths[i]); } } /** * tb_tunnel_port_on_path() - Does the tunnel go through port * @tunnel: Tunnel to check * @port: Port to check * * Returns true if @tunnel goes through @port (direction does not matter), * false otherwise. */ bool tb_tunnel_port_on_path(const struct tb_tunnel *tunnel, const struct tb_port *port) { int i; for (i = 0; i < tunnel->npaths; i++) { if (!tunnel->paths[i]) continue; if (tb_path_port_on_path(tunnel->paths[i], port)) return true; } return false; } static bool tb_tunnel_is_active(const struct tb_tunnel *tunnel) { int i; for (i = 0; i < tunnel->npaths; i++) { if (!tunnel->paths[i]) return false; if (!tunnel->paths[i]->activated) return false; } return true; } /** * tb_tunnel_maximum_bandwidth() - Return maximum possible bandwidth * @tunnel: Tunnel to check * @max_up: Maximum upstream bandwidth in Mb/s * @max_down: Maximum downstream bandwidth in Mb/s * * Returns maximum possible bandwidth this tunnel can go if not limited * by other bandwidth clients. If the tunnel does not support this * returns %-EOPNOTSUPP. */ int tb_tunnel_maximum_bandwidth(struct tb_tunnel *tunnel, int *max_up, int *max_down) { if (!tb_tunnel_is_active(tunnel)) return -EINVAL; if (tunnel->maximum_bandwidth) return tunnel->maximum_bandwidth(tunnel, max_up, max_down); return -EOPNOTSUPP; } /** * tb_tunnel_allocated_bandwidth() - Return bandwidth allocated for the tunnel * @tunnel: Tunnel to check * @allocated_up: Currently allocated upstream bandwidth in Mb/s is stored here * @allocated_down: Currently allocated downstream bandwidth in Mb/s is * stored here * * Returns the bandwidth allocated for the tunnel. This may be higher * than what the tunnel actually consumes. */ int tb_tunnel_allocated_bandwidth(struct tb_tunnel *tunnel, int *allocated_up, int *allocated_down) { if (!tb_tunnel_is_active(tunnel)) return -EINVAL; if (tunnel->allocated_bandwidth) return tunnel->allocated_bandwidth(tunnel, allocated_up, allocated_down); return -EOPNOTSUPP; } /** * tb_tunnel_alloc_bandwidth() - Change tunnel bandwidth allocation * @tunnel: Tunnel whose bandwidth allocation to change * @alloc_up: New upstream bandwidth in Mb/s * @alloc_down: New downstream bandwidth in Mb/s * * Tries to change tunnel bandwidth allocation. If succeeds returns %0 * and updates @alloc_up and @alloc_down to that was actually allocated * (it may not be the same as passed originally). Returns negative errno * in case of failure. */ int tb_tunnel_alloc_bandwidth(struct tb_tunnel *tunnel, int *alloc_up, int *alloc_down) { if (!tb_tunnel_is_active(tunnel)) return -EINVAL; if (tunnel->alloc_bandwidth) return tunnel->alloc_bandwidth(tunnel, alloc_up, alloc_down); return -EOPNOTSUPP; } /** * tb_tunnel_consumed_bandwidth() - Return bandwidth consumed by the tunnel * @tunnel: Tunnel to check * @consumed_up: Consumed bandwidth in Mb/s from @dst_port to @src_port. * Can be %NULL. * @consumed_down: Consumed bandwidth in Mb/s from @src_port to @dst_port. * Can be %NULL. * * Stores the amount of isochronous bandwidth @tunnel consumes in * @consumed_up and @consumed_down. In case of success returns %0, * negative errno otherwise. */ int tb_tunnel_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up, int *consumed_down) { int up_bw = 0, down_bw = 0; if (!tb_tunnel_is_active(tunnel)) goto out; if (tunnel->consumed_bandwidth) { int ret; ret = tunnel->consumed_bandwidth(tunnel, &up_bw, &down_bw); if (ret) return ret; tb_tunnel_dbg(tunnel, "consumed bandwidth %d/%d Mb/s\n", up_bw, down_bw); } out: if (consumed_up) *consumed_up = up_bw; if (consumed_down) *consumed_down = down_bw; return 0; } /** * tb_tunnel_release_unused_bandwidth() - Release unused bandwidth * @tunnel: Tunnel whose unused bandwidth to release * * If tunnel supports dynamic bandwidth management (USB3 tunnels at the * moment) this function makes it to release all the unused bandwidth. * * Returns %0 in case of success and negative errno otherwise. */ int tb_tunnel_release_unused_bandwidth(struct tb_tunnel *tunnel) { if (!tb_tunnel_is_active(tunnel)) return 0; if (tunnel->release_unused_bandwidth) { int ret; ret = tunnel->release_unused_bandwidth(tunnel); if (ret) return ret; } return 0; } /** * tb_tunnel_reclaim_available_bandwidth() - Reclaim available bandwidth * @tunnel: Tunnel reclaiming available bandwidth * @available_up: Available upstream bandwidth (in Mb/s) * @available_down: Available downstream bandwidth (in Mb/s) * * Reclaims bandwidth from @available_up and @available_down and updates * the variables accordingly (e.g decreases both according to what was * reclaimed by the tunnel). If nothing was reclaimed the values are * kept as is. */ void tb_tunnel_reclaim_available_bandwidth(struct tb_tunnel *tunnel, int *available_up, int *available_down) { if (!tb_tunnel_is_active(tunnel)) return; if (tunnel->reclaim_available_bandwidth) tunnel->reclaim_available_bandwidth(tunnel, available_up, available_down); } const char *tb_tunnel_type_name(const struct tb_tunnel *tunnel) { return tb_tunnel_names[tunnel->type]; }