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#include <linux/slab.h>#include <linux/errno.h>#include <linux/delay.h>#include <linux/ktime.h>
#include "tb.h"
static void tb_dump_hop(const struct tb_path_hop *hop, const struct tb_regs_hop *regs){ const struct tb_port *port = hop->in_port;
tb_port_dbg(port, " In HopID: %d => Out port: %d Out HopID: %d\n", hop->in_hop_index, regs->out_port, regs->next_hop); tb_port_dbg(port, " Weight: %d Priority: %d Credits: %d Drop: %d PM: %d\n", regs->weight, regs->priority, regs->initial_credits, regs->drop_packages, regs->pmps); tb_port_dbg(port, " Counter enabled: %d Counter index: %d\n", regs->counter_enable, regs->counter); tb_port_dbg(port, " Flow Control (In/Eg): %d/%d Shared Buffer (In/Eg): %d/%d\n", regs->ingress_fc, regs->egress_fc, regs->ingress_shared_buffer, regs->egress_shared_buffer); tb_port_dbg(port, " Unknown1: %#x Unknown2: %#x Unknown3: %#x\n", regs->unknown1, regs->unknown2, regs->unknown3);}
static struct tb_port *tb_path_find_dst_port(struct tb_port *src, int src_hopid, int dst_hopid){ struct tb_port *port, *out_port = NULL; struct tb_regs_hop hop; struct tb_switch *sw; int i, ret, hopid;
hopid = src_hopid; port = src;
for (i = 0; port && i < TB_PATH_MAX_HOPS; i++) { sw = port->sw;
ret = tb_port_read(port, &hop, TB_CFG_HOPS, 2 * hopid, 2); if (ret) { tb_port_warn(port, "failed to read path at %d\n", hopid); return NULL; }
if (!hop.enable) return NULL;
out_port = &sw->ports[hop.out_port]; hopid = hop.next_hop; port = out_port->remote; }
return out_port && hopid == dst_hopid ? out_port : NULL;}
static int tb_path_find_src_hopid(struct tb_port *src, const struct tb_port *dst, int dst_hopid){ struct tb_port *out; int i;
for (i = TB_PATH_MIN_HOPID; i <= src->config.max_in_hop_id; i++) { out = tb_path_find_dst_port(src, i, dst_hopid); if (out == dst) return i; }
return 0;}
/** * tb_path_discover() - Discover a path * @src: First input port of a path * @src_hopid: Starting HopID of a path (%-1 if don't care) * @dst: Expected destination port of the path (%NULL if don't care) * @dst_hopid: HopID to the @dst (%-1 if don't care) * @last: Last port is filled here if not %NULL * @name: Name of the path * @alloc_hopid: Allocate HopIDs for the ports * * Follows a path starting from @src and @src_hopid to the last output * port of the path. Allocates HopIDs for the visited ports (if * @alloc_hopid is true). Call tb_path_free() to release the path and * allocated HopIDs when the path is not needed anymore. * * Note function discovers also incomplete paths so caller should check * that the @dst port is the expected one. If it is not, the path can be * cleaned up by calling tb_path_deactivate() before tb_path_free(). * * Return: Pointer to &struct tb_path, %NULL in case of failure. */struct tb_path *tb_path_discover(struct tb_port *src, int src_hopid, struct tb_port *dst, int dst_hopid, struct tb_port **last, const char *name, bool alloc_hopid){ struct tb_port *out_port; struct tb_regs_hop hop; struct tb_path *path; struct tb_switch *sw; struct tb_port *p; size_t num_hops; int ret, i, h;
if (src_hopid < 0 && dst) { /* * For incomplete paths the intermediate HopID can be * different from the one used by the protocol adapter * so in that case find a path that ends on @dst with * matching @dst_hopid. That should give us the correct * HopID for the @src. */ src_hopid = tb_path_find_src_hopid(src, dst, dst_hopid); if (!src_hopid) return NULL; }
p = src; h = src_hopid; num_hops = 0;
for (i = 0; p && i < TB_PATH_MAX_HOPS; i++) { sw = p->sw;
ret = tb_port_read(p, &hop, TB_CFG_HOPS, 2 * h, 2); if (ret) { tb_port_warn(p, "failed to read path at %d\n", h); return NULL; }
/* If the hop is not enabled we got an incomplete path */ if (!hop.enable) break;
out_port = &sw->ports[hop.out_port]; if (last) *last = out_port;
h = hop.next_hop; p = out_port->remote; num_hops++; }
path = kzalloc_flex(*path, hops, num_hops); if (!path) return NULL;
path->path_length = num_hops;
path->name = name; path->tb = src->sw->tb; path->activated = true; path->alloc_hopid = alloc_hopid;
tb_dbg(path->tb, "discovering %s path starting from %llx:%u\n", path->name, tb_route(src->sw), src->port);
p = src; h = src_hopid;
for (i = 0; i < num_hops; i++) { int next_hop;
sw = p->sw;
ret = tb_port_read(p, &hop, TB_CFG_HOPS, 2 * h, 2); if (ret) { tb_port_warn(p, "failed to read path at %d\n", h); goto err; }
if (alloc_hopid && tb_port_alloc_in_hopid(p, h, h) < 0) goto err;
out_port = &sw->ports[hop.out_port]; next_hop = hop.next_hop;
if (alloc_hopid && tb_port_alloc_out_hopid(out_port, next_hop, next_hop) < 0) { tb_port_release_in_hopid(p, h); goto err; }
path->hops[i].in_port = p; path->hops[i].in_hop_index = h; path->hops[i].in_counter_index = -1; path->hops[i].out_port = out_port; path->hops[i].next_hop_index = next_hop;
tb_dump_hop(&path->hops[i], &hop);
h = next_hop; p = out_port->remote; }
tb_dbg(path->tb, "path discovery complete\n"); return path;
err: tb_port_warn(src, "failed to discover path starting at HopID %d\n", src_hopid); tb_path_free(path); return NULL;}
/** * tb_path_alloc() - allocate a thunderbolt path between two ports * @tb: Domain pointer * @src: Source port of the path * @src_hopid: HopID used for the first ingress port in the path * @dst: Destination port of the path * @dst_hopid: HopID used for the last egress port in the path * @link_nr: Preferred link if there are dual links on the path * @name: Name of the path * * Creates path between two ports starting with given @src_hopid. Reserves * HopIDs for each port (they can be different from @src_hopid depending on * how many HopIDs each port already have reserved). If there are dual * links on the path, prioritizes using @link_nr but takes into account * that the lanes may be bonded. * * Return: Pointer to &struct tb_path, %NULL in case of failure. */struct tb_path *tb_path_alloc(struct tb *tb, struct tb_port *src, int src_hopid, struct tb_port *dst, int dst_hopid, int link_nr, const char *name){ struct tb_port *in_port, *out_port, *first_port, *last_port; int in_hopid, out_hopid; struct tb_path *path; size_t num_hops; int i, ret;
first_port = last_port = NULL; i = 0; tb_for_each_port_on_path(src, dst, in_port) { if (!first_port) first_port = in_port; last_port = in_port; i++; }
/* Check that src and dst are reachable */ if (first_port != src || last_port != dst) return NULL;
/* Each hop takes two ports */ num_hops = i / 2;
path = kzalloc_flex(*path, hops, num_hops); if (!path) return NULL;
path->path_length = num_hops; path->alloc_hopid = true;
in_hopid = src_hopid; out_port = NULL;
for (i = 0; i < num_hops; i++) { in_port = tb_next_port_on_path(src, dst, out_port); if (!in_port) goto err;
/* When lanes are bonded primary link must be used */ if (!in_port->bonded && in_port->dual_link_port && in_port->link_nr != link_nr) in_port = in_port->dual_link_port;
ret = tb_port_alloc_in_hopid(in_port, in_hopid, in_hopid); if (ret < 0) goto err; in_hopid = ret;
out_port = tb_next_port_on_path(src, dst, in_port); if (!out_port) goto err;
/* * Pick up right port when going from non-bonded to * bonded or from bonded to non-bonded. */ if (out_port->dual_link_port) { if (!in_port->bonded && out_port->bonded && out_port->link_nr) { /* * Use primary link when going from * non-bonded to bonded. */ out_port = out_port->dual_link_port; } else if (!out_port->bonded && out_port->link_nr != link_nr) { /* * If out port is not bonded follow * link_nr. */ out_port = out_port->dual_link_port; } }
if (i == num_hops - 1) ret = tb_port_alloc_out_hopid(out_port, dst_hopid, dst_hopid); else ret = tb_port_alloc_out_hopid(out_port, -1, -1);
if (ret < 0) goto err; out_hopid = ret;
path->hops[i].in_hop_index = in_hopid; path->hops[i].in_port = in_port; path->hops[i].in_counter_index = -1; path->hops[i].out_port = out_port; path->hops[i].next_hop_index = out_hopid;
in_hopid = out_hopid; }
path->tb = tb; path->name = name;
return path;
err: tb_path_free(path); return NULL;}
/** * tb_path_free() - free a path * @path: Path to free * * Frees a path. The path does not need to be deactivated. */void tb_path_free(struct tb_path *path){ if (path->alloc_hopid) { int i;
for (i = 0; i < path->path_length; i++) { const struct tb_path_hop *hop = &path->hops[i];
if (hop->in_port) tb_port_release_in_hopid(hop->in_port, hop->in_hop_index); if (hop->out_port) tb_port_release_out_hopid(hop->out_port, hop->next_hop_index); } }
kfree(path);}
static void __tb_path_deallocate_nfc(struct tb_path *path, int first_hop){ int i, res; for (i = first_hop; i < path->path_length; i++) { res = tb_port_add_nfc_credits(path->hops[i].in_port, -path->hops[i].nfc_credits); if (res) tb_port_warn(path->hops[i].in_port, "nfc credits deallocation failed for hop %d\n", i); }}
static int __tb_path_deactivate_hop(struct tb_port *port, int hop_index, bool clear_fc){ struct tb_regs_hop hop; ktime_t timeout; int ret;
/* Disable the path */ ret = tb_port_read(port, &hop, TB_CFG_HOPS, 2 * hop_index, 2); if (ret) return ret;
/* Already disabled */ if (!hop.enable) return 0;
hop.enable = 0;
ret = tb_port_write(port, &hop, TB_CFG_HOPS, 2 * hop_index, 2); if (ret) return ret;
/* Wait until it is drained */ timeout = ktime_add_ms(ktime_get(), 500); do { ret = tb_port_read(port, &hop, TB_CFG_HOPS, 2 * hop_index, 2); if (ret) return ret;
if (!hop.pending) { if (clear_fc) { /* * Clear flow control. Protocol adapters * IFC and ISE bits are vendor defined * in the USB4 spec so we clear them * only for pre-USB4 adapters. */ if (tb_port_is_null(port) || !tb_switch_is_usb4(port->sw)) { hop.ingress_fc = 0; hop.ingress_shared_buffer = 0; } hop.egress_fc = 0; hop.egress_shared_buffer = 0;
return tb_port_write(port, &hop, TB_CFG_HOPS, 2 * hop_index, 2); }
return 0; }
usleep_range(10, 20); } while (ktime_before(ktime_get(), timeout));
return -ETIMEDOUT;}
/** * tb_path_deactivate_hop() - Deactivate one path in path config space * @port: Lane or protocol adapter * @hop_index: HopID of the path to be cleared * * This deactivates or clears a single path config space entry at * @hop_index. * * Return: %0 on success, negative errno otherwise. */int tb_path_deactivate_hop(struct tb_port *port, int hop_index){ return __tb_path_deactivate_hop(port, hop_index, true);}
static void __tb_path_deactivate_hops(struct tb_path *path, int first_hop){ int i, res;
for (i = first_hop; i < path->path_length; i++) { res = __tb_path_deactivate_hop(path->hops[i].in_port, path->hops[i].in_hop_index, path->clear_fc); if (res && res != -ENODEV) tb_port_warn(path->hops[i].in_port, "hop deactivation failed for hop %d, index %d\n", i, path->hops[i].in_hop_index); }}
void tb_path_deactivate(struct tb_path *path){ if (!path->activated) { tb_WARN(path->tb, "trying to deactivate an inactive path\n"); return; } tb_dbg(path->tb, "deactivating %s path from %llx:%u to %llx:%u\n", path->name, tb_route(path->hops[0].in_port->sw), path->hops[0].in_port->port, tb_route(path->hops[path->path_length - 1].out_port->sw), path->hops[path->path_length - 1].out_port->port); __tb_path_deactivate_hops(path, 0); __tb_path_deallocate_nfc(path, 0); path->activated = false;}
/** * tb_path_activate() - activate a path * @path: Path to activate * * Activate a path starting with the first hop and ending on the last hop. The * caller must fill path->hops before calling tb_path_activate(). * * Return: %0 on success, negative errno otherwise. */int tb_path_activate(struct tb_path *path){ int i, res; enum tb_path_port out_mask, in_mask; if (path->activated) { tb_WARN(path->tb, "trying to activate already activated path\n"); return -EINVAL; }
tb_dbg(path->tb, "activating %s path from %llx:%u to %llx:%u\n", path->name, tb_route(path->hops[0].in_port->sw), path->hops[0].in_port->port, tb_route(path->hops[path->path_length - 1].out_port->sw), path->hops[path->path_length - 1].out_port->port);
/* Clear counters. */ for (i = path->path_length - 1; i >= 0; i--) { if (path->hops[i].in_counter_index == -1) continue; res = tb_port_clear_counter(path->hops[i].in_port, path->hops[i].in_counter_index); if (res) goto err; }
/* Add non flow controlled credits. */ for (i = path->path_length - 1; i >= 0; i--) { res = tb_port_add_nfc_credits(path->hops[i].in_port, path->hops[i].nfc_credits); if (res) { __tb_path_deallocate_nfc(path, i); goto err; } }
/* Activate hops. */ for (i = 0; i < path->path_length; i++) { struct tb_regs_hop hop = { 0 };
/* If it is left active deactivate it first */ __tb_path_deactivate_hop(path->hops[i].in_port, path->hops[i].in_hop_index, path->clear_fc);
/* Needed for USB4 routers, read path config space before write */ res = tb_port_read(path->hops[i].in_port, &hop, TB_CFG_HOPS, 2 * path->hops[i].in_hop_index, 2); if (res) goto err;
hop.next_hop = path->hops[i].next_hop_index; hop.out_port = path->hops[i].out_port->port; hop.pmps = path->hops[i].pm_support; hop.unknown1 = 0; hop.enable = 1;
out_mask = (i == path->path_length - 1) ? TB_PATH_DESTINATION : TB_PATH_INTERNAL; in_mask = (i == 0) ? TB_PATH_SOURCE : TB_PATH_INTERNAL; hop.weight = path->weight; hop.unknown2 = 0; hop.priority = path->priority; hop.drop_packages = path->drop_packages; hop.counter = path->hops[i].in_counter_index; hop.counter_enable = path->hops[i].in_counter_index != -1; hop.egress_fc = path->egress_fc_enable & out_mask; hop.egress_shared_buffer = path->egress_shared_buffer & out_mask; /* * Protocol adapters IFC and ISE bits, and Path Credits * Allocated are vendor defined in the USB4 spec so we * program them only for pre-USB4 and lane adapters. */ if (tb_port_is_null(path->hops[i].in_port) || !tb_switch_is_usb4(path->hops[i].in_port->sw)) { hop.initial_credits = path->hops[i].initial_credits; hop.ingress_fc = path->ingress_fc_enable & in_mask; hop.ingress_shared_buffer = path->ingress_shared_buffer & in_mask; }
hop.unknown3 = 0;
tb_port_dbg(path->hops[i].in_port, "Writing hop %d\n", i); tb_dump_hop(&path->hops[i], &hop); res = tb_port_write(path->hops[i].in_port, &hop, TB_CFG_HOPS, 2 * path->hops[i].in_hop_index, 2); if (res) { __tb_path_deactivate_hops(path, 0); __tb_path_deallocate_nfc(path, 0); goto err; } } path->activated = true; tb_dbg(path->tb, "%s path activation complete\n", path->name); return 0;err: tb_warn(path->tb, "%s path activation failed: %d\n", path->name, res); return res;}
/** * tb_path_is_invalid() - check whether any ports on the path are invalid * @path: Path to check * * Return: %true if the path is invalid, %false otherwise. */bool tb_path_is_invalid(struct tb_path *path){ int i = 0; for (i = 0; i < path->path_length; i++) { if (path->hops[i].in_port->sw->is_unplugged) return true; if (path->hops[i].out_port->sw->is_unplugged) return true; } return false;}
/** * tb_path_port_on_path() - Does the path go through certain port * @path: Path to check * @port: Switch to check * * Goes over all hops on path and checks if @port is any of them. * Direction does not matter. * * Return: %true if port is on the path, %false otherwise. */bool tb_path_port_on_path(const struct tb_path *path, const struct tb_port *port){ int i;
for (i = 0; i < path->path_length; i++) { if (path->hops[i].in_port == port || path->hops[i].out_port == port) return true; }
return false;}