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Release 4.14 drivers/thunderbolt/path.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Thunderbolt Cactus Ridge driver - path/tunnel functionality
 *
 * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
 */

#include <linux/slab.h>
#include <linux/errno.h>

#include "tb.h"



static void tb_dump_hop(struct tb_port *port, struct tb_regs_hop *hop) { tb_port_info(port, " Hop through port %d to hop %d (%s)\n", hop->out_port, hop->next_hop, hop->enable ? "enabled" : "disabled"); tb_port_info(port, " Weight: %d Priority: %d Credits: %d Drop: %d\n", hop->weight, hop->priority, hop->initial_credits, hop->drop_packages); tb_port_info(port, " Counter enabled: %d Counter index: %d\n", hop->counter_enable, hop->counter); tb_port_info(port, " Flow Control (In/Eg): %d/%d Shared Buffer (In/Eg): %d/%d\n", hop->ingress_fc, hop->egress_fc, hop->ingress_shared_buffer, hop->egress_shared_buffer); tb_port_info(port, " Unknown1: %#x Unknown2: %#x Unknown3: %#x\n", hop->unknown1, hop->unknown2, hop->unknown3); }

Contributors

PersonTokensPropCommitsCommitProp
Andreas Noever119100.00%1100.00%
Total119100.00%1100.00%

/** * tb_path_alloc() - allocate a thunderbolt path * * Return: Returns a tb_path on success or NULL on failure. */
struct tb_path *tb_path_alloc(struct tb *tb, int num_hops) { struct tb_path *path = kzalloc(sizeof(*path), GFP_KERNEL); if (!path) return NULL; path->hops = kcalloc(num_hops, sizeof(*path->hops), GFP_KERNEL); if (!path->hops) { kfree(path); return NULL; } path->tb = tb; path->path_length = num_hops; return path; }

Contributors

PersonTokensPropCommitsCommitProp
Andreas Noever90100.00%1100.00%
Total90100.00%1100.00%

/** * tb_path_free() - free a deactivated path */
void tb_path_free(struct tb_path *path) { if (path->activated) { tb_WARN(path->tb, "trying to free an activated path\n") return; } kfree(path->hops); kfree(path); }

Contributors

PersonTokensPropCommitsCommitProp
Andreas Noever37100.00%1100.00%
Total37100.00%1100.00%


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->nfc_credits); if (res) tb_port_warn(path->hops[i].in_port, "nfc credits deallocation failed for hop %d\n", i); } }

Contributors

PersonTokensPropCommitsCommitProp
Andreas Noever75100.00%1100.00%
Total75100.00%1100.00%


static void __tb_path_deactivate_hops(struct tb_path *path, int first_hop) { int i, res; struct tb_regs_hop hop = { }; for (i = first_hop; i < path->path_length; i++) { res = tb_port_write(path->hops[i].in_port, &hop, TB_CFG_HOPS, 2 * path->hops[i].in_hop_index, 2); if (res) tb_port_warn(path->hops[i].in_port, "hop deactivation failed for hop %d, index %d\n", i, path->hops[i].in_hop_index); } }

Contributors

PersonTokensPropCommitsCommitProp
Andreas Noever103100.00%1100.00%
Total103100.00%1100.00%


void tb_path_deactivate(struct tb_path *path) { if (!path->activated) { tb_WARN(path->tb, "trying to deactivate an inactive path\n"); return; } tb_info(path->tb, "deactivating path from %llx:%x to %llx:%x\n", 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; }

Contributors

PersonTokensPropCommitsCommitProp
Andreas Noever116100.00%1100.00%
Total116100.00%1100.00%

/** * tb_path_activate() - activate a path * * Activate a path starting with the last hop and iterating backwards. The * caller must fill path->hops before calling tb_path_activate(). * * Return: Returns 0 on success or an error code on failure. */
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_info(path->tb, "activating path from %llx:%x to %llx:%x\n", 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->nfc_credits); if (res) { __tb_path_deallocate_nfc(path, i); goto err; } } /* Activate hops. */ for (i = path->path_length - 1; i >= 0; i--) { struct tb_regs_hop hop = { 0 }; /* * We do (currently) not tear down paths setup by the firmeware. * If a firmware device is unplugged and plugged in again then * it can happen that we reuse some of the hops from the (now * defunct) firmeware path. This causes the hotplug operation to * fail (the pci device does not show up). Clearing the hop * before overwriting it fixes the problem. * * Should be removed once we discover and tear down firmeware * paths. */ 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, i); __tb_path_deallocate_nfc(path, 0); goto err; } /* dword 0 */ hop.next_hop = path->hops[i].next_hop_index; hop.out_port = path->hops[i].out_port->port; /* TODO: figure out why these are good values */ hop.initial_credits = (i == path->path_length - 1) ? 16 : 7; hop.unknown1 = 0; hop.enable = 1; /* dword 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.ingress_fc = path->ingress_fc_enable & in_mask; hop.egress_fc = path->egress_fc_enable & out_mask; hop.ingress_shared_buffer = path->ingress_shared_buffer & in_mask; hop.egress_shared_buffer = path->egress_shared_buffer & out_mask; hop.unknown3 = 0; tb_port_info(path->hops[i].in_port, "Writing hop %d, index %d", i, path->hops[i].in_hop_index); tb_dump_hop(path->hops[i].in_port, &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, i); __tb_path_deallocate_nfc(path, 0); goto err; } } path->activated = true; tb_info(path->tb, "path activation complete\n"); return 0; err: tb_WARN(path->tb, "path activation failed\n"); return res; }

Contributors

PersonTokensPropCommitsCommitProp
Andreas Noever633100.00%2100.00%
Total633100.00%2100.00%

/** * tb_path_is_invalid() - check whether any ports on the path are invalid * * Return: Returns 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; }

Contributors

PersonTokensPropCommitsCommitProp
Andreas Noever71100.00%1100.00%
Total71100.00%1100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Andreas Noever125899.92%266.67%
Greg Kroah-Hartman10.08%133.33%
Total1259100.00%3100.00%
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