// SPDX-License-Identifier: GPL-2.0
/*
- * Thunderbolt Cactus Ridge driver - path/tunnel functionality
+ * Thunderbolt driver - path/tunnel functionality
*
* 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/ktime.h>
#include "tb.h"
-
-static void tb_dump_hop(struct tb_port *port, struct tb_regs_hop *hop)
+static void tb_dump_hop(const struct tb_path_hop *hop, const struct tb_regs_hop *regs)
{
- tb_port_dbg(port, " Hop through port %d to hop %d (%s)\n",
- hop->out_port, hop->next_hop,
- hop->enable ? "enabled" : "disabled");
+ 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\n",
- hop->weight, hop->priority,
- hop->initial_credits, hop->drop_packages);
+ regs->weight, regs->priority,
+ regs->initial_credits, regs->drop_packages);
tb_port_dbg(port, " Counter enabled: %d Counter index: %d\n",
- hop->counter_enable, hop->counter);
+ regs->counter_enable, regs->counter);
tb_port_dbg(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);
+ 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",
- hop->unknown1, hop->unknown2, hop->unknown3);
+ 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
+ *
+ * Follows a path starting from @src and @src_hopid to the last output
+ * port of the path. Allocates HopIDs for the visited ports. 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: Discovered path on success, %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)
+{
+ 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(sizeof(*path), GFP_KERNEL);
+ if (!path)
+ return NULL;
+
+ path->name = name;
+ path->tb = src->sw->tb;
+ path->path_length = num_hops;
+ path->activated = true;
+
+ path->hops = kcalloc(num_hops, sizeof(*path->hops), GFP_KERNEL);
+ if (!path->hops) {
+ kfree(path);
+ return NULL;
+ }
+
+ 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 (tb_port_alloc_in_hopid(p, h, h) < 0)
+ goto err;
+
+ out_port = &sw->ports[hop.out_port];
+ next_hop = hop.next_hop;
+
+ if (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;
+
+ h = next_hop;
+ p = out_port->remote;
+ }
+
+ 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
+ * 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.
*
* 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 *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_path *path = kzalloc(sizeof(*path), GFP_KERNEL);
+ struct tb_port *in_port, *out_port;
+ int in_hopid, out_hopid;
+ struct tb_path *path;
+ size_t num_hops;
+ int i, ret;
+
+ path = kzalloc(sizeof(*path), GFP_KERNEL);
if (!path)
return NULL;
+
+ /*
+ * Number of hops on a path is the distance between the two
+ * switches plus the source adapter port.
+ */
+ num_hops = abs(tb_route_length(tb_route(src->sw)) -
+ tb_route_length(tb_route(dst->sw))) + 1;
+
path->hops = kcalloc(num_hops, sizeof(*path->hops), GFP_KERNEL);
if (!path->hops) {
kfree(path);
return NULL;
}
+
+ 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;
+
+ if (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;
+
+ if (out_port->dual_link_port && out_port->link_nr != 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->path_length = num_hops;
+ path->name = name;
+
return path;
+
+err:
+ tb_path_free(path);
+ return NULL;
}
/**
- * tb_path_free() - free a deactivated path
+ * 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->activated) {
- tb_WARN(path->tb, "trying to free an activated path\n")
- return;
+ 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->hops);
kfree(path);
}
}
}
+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 */
+ hop.ingress_fc = 0;
+ hop.egress_fc = 0;
+ hop.ingress_shared_buffer = 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;
+}
+
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)
+ 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);
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_dbg(path->tb,
+ "deactivating %s path from %llx:%x to %llx:%x\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;
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);
+ tb_dbg(path->tb,
+ "activating %s path from %llx:%x to %llx:%x\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--) {
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;
- }
+ /* 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);
/* 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.initial_credits = path->hops[i].initial_credits;
hop.unknown1 = 0;
hop.enable = 1;
& 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);
+ 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) {
}
}
path->activated = true;
- tb_info(path->tb, "path activation complete\n");
+ tb_dbg(path->tb, "path activation complete\n");
return 0;
err:
tb_WARN(path->tb, "path activation failed\n");
git.samba.org / sfrench / cifs-2.6.git / blobdiff