--- /dev/null
+/*
+ * 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);
+}
+
+/**
+ * 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;
+}
+
+/**
+ * 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);
+}
+
+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);
+ }
+}
+
+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);
+ }
+}
+
+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;
+}
+
+/**
+ * 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;
+}
+
+/**
+ * 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;
+}
Code Review / kvmfornfv.git / blobdiff