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path: root/drivers/thunderbolt/switch.c
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-rw-r--r--drivers/thunderbolt/switch.c507
1 files changed, 507 insertions, 0 deletions
diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
new file mode 100644
index 000000000000..aeb982969629
--- /dev/null
+++ b/drivers/thunderbolt/switch.c
@@ -0,0 +1,507 @@
+/*
+ * Thunderbolt Cactus Ridge driver - switch/port utility functions
+ *
+ * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
+ */
+
+#include <linux/delay.h>
+#include <linux/slab.h>
+
+#include "tb.h"
+
+/* port utility functions */
+
+static const char *tb_port_type(struct tb_regs_port_header *port)
+{
+ switch (port->type >> 16) {
+ case 0:
+ switch ((u8) port->type) {
+ case 0:
+ return "Inactive";
+ case 1:
+ return "Port";
+ case 2:
+ return "NHI";
+ default:
+ return "unknown";
+ }
+ case 0x2:
+ return "Ethernet";
+ case 0x8:
+ return "SATA";
+ case 0xe:
+ return "DP/HDMI";
+ case 0x10:
+ return "PCIe";
+ case 0x20:
+ return "USB";
+ default:
+ return "unknown";
+ }
+}
+
+static void tb_dump_port(struct tb *tb, struct tb_regs_port_header *port)
+{
+ tb_info(tb,
+ " Port %d: %x:%x (Revision: %d, TB Version: %d, Type: %s (%#x))\n",
+ port->port_number, port->vendor_id, port->device_id,
+ port->revision, port->thunderbolt_version, tb_port_type(port),
+ port->type);
+ tb_info(tb, " Max hop id (in/out): %d/%d\n",
+ port->max_in_hop_id, port->max_out_hop_id);
+ tb_info(tb, " Max counters: %d\n", port->max_counters);
+ tb_info(tb, " NFC Credits: %#x\n", port->nfc_credits);
+}
+
+/**
+ * tb_port_state() - get connectedness state of a port
+ *
+ * The port must have a TB_CAP_PHY (i.e. it should be a real port).
+ *
+ * Return: Returns an enum tb_port_state on success or an error code on failure.
+ */
+static int tb_port_state(struct tb_port *port)
+{
+ struct tb_cap_phy phy;
+ int res;
+ if (port->cap_phy == 0) {
+ tb_port_WARN(port, "does not have a PHY\n");
+ return -EINVAL;
+ }
+ res = tb_port_read(port, &phy, TB_CFG_PORT, port->cap_phy, 2);
+ if (res)
+ return res;
+ return phy.state;
+}
+
+/**
+ * tb_wait_for_port() - wait for a port to become ready
+ *
+ * Wait up to 1 second for a port to reach state TB_PORT_UP. If
+ * wait_if_unplugged is set then we also wait if the port is in state
+ * TB_PORT_UNPLUGGED (it takes a while for the device to be registered after
+ * switch resume). Otherwise we only wait if a device is registered but the link
+ * has not yet been established.
+ *
+ * Return: Returns an error code on failure. Returns 0 if the port is not
+ * connected or failed to reach state TB_PORT_UP within one second. Returns 1
+ * if the port is connected and in state TB_PORT_UP.
+ */
+int tb_wait_for_port(struct tb_port *port, bool wait_if_unplugged)
+{
+ int retries = 10;
+ int state;
+ if (!port->cap_phy) {
+ tb_port_WARN(port, "does not have PHY\n");
+ return -EINVAL;
+ }
+ if (tb_is_upstream_port(port)) {
+ tb_port_WARN(port, "is the upstream port\n");
+ return -EINVAL;
+ }
+
+ while (retries--) {
+ state = tb_port_state(port);
+ if (state < 0)
+ return state;
+ if (state == TB_PORT_DISABLED) {
+ tb_port_info(port, "is disabled (state: 0)\n");
+ return 0;
+ }
+ if (state == TB_PORT_UNPLUGGED) {
+ if (wait_if_unplugged) {
+ /* used during resume */
+ tb_port_info(port,
+ "is unplugged (state: 7), retrying...\n");
+ msleep(100);
+ continue;
+ }
+ tb_port_info(port, "is unplugged (state: 7)\n");
+ return 0;
+ }
+ if (state == TB_PORT_UP) {
+ tb_port_info(port,
+ "is connected, link is up (state: 2)\n");
+ return 1;
+ }
+
+ /*
+ * After plug-in the state is TB_PORT_CONNECTING. Give it some
+ * time.
+ */
+ tb_port_info(port,
+ "is connected, link is not up (state: %d), retrying...\n",
+ state);
+ msleep(100);
+ }
+ tb_port_warn(port,
+ "failed to reach state TB_PORT_UP. Ignoring port...\n");
+ return 0;
+}
+
+/**
+ * tb_port_add_nfc_credits() - add/remove non flow controlled credits to port
+ *
+ * Change the number of NFC credits allocated to @port by @credits. To remove
+ * NFC credits pass a negative amount of credits.
+ *
+ * Return: Returns 0 on success or an error code on failure.
+ */
+int tb_port_add_nfc_credits(struct tb_port *port, int credits)
+{
+ if (credits == 0)
+ return 0;
+ tb_port_info(port,
+ "adding %#x NFC credits (%#x -> %#x)",
+ credits,
+ port->config.nfc_credits,
+ port->config.nfc_credits + credits);
+ port->config.nfc_credits += credits;
+ return tb_port_write(port, &port->config.nfc_credits,
+ TB_CFG_PORT, 4, 1);
+}
+
+/**
+ * tb_port_clear_counter() - clear a counter in TB_CFG_COUNTER
+ *
+ * Return: Returns 0 on success or an error code on failure.
+ */
+int tb_port_clear_counter(struct tb_port *port, int counter)
+{
+ u32 zero[3] = { 0, 0, 0 };
+ tb_port_info(port, "clearing counter %d\n", counter);
+ return tb_port_write(port, zero, TB_CFG_COUNTERS, 3 * counter, 3);
+}
+
+/**
+ * tb_init_port() - initialize a port
+ *
+ * This is a helper method for tb_switch_alloc. Does not check or initialize
+ * any downstream switches.
+ *
+ * Return: Returns 0 on success or an error code on failure.
+ */
+static int tb_init_port(struct tb_port *port)
+{
+ int res;
+ int cap;
+
+ res = tb_port_read(port, &port->config, TB_CFG_PORT, 0, 8);
+ if (res)
+ return res;
+
+ /* Port 0 is the switch itself and has no PHY. */
+ if (port->config.type == TB_TYPE_PORT && port->port != 0) {
+ cap = tb_find_cap(port, TB_CFG_PORT, TB_CAP_PHY);
+
+ if (cap > 0)
+ port->cap_phy = cap;
+ else
+ tb_port_WARN(port, "non switch port without a PHY\n");
+ }
+
+ tb_dump_port(port->sw->tb, &port->config);
+
+ /* TODO: Read dual link port, DP port and more from EEPROM. */
+ return 0;
+
+}
+
+/* switch utility functions */
+
+static void tb_dump_switch(struct tb *tb, struct tb_regs_switch_header *sw)
+{
+ tb_info(tb,
+ " Switch: %x:%x (Revision: %d, TB Version: %d)\n",
+ sw->vendor_id, sw->device_id, sw->revision,
+ sw->thunderbolt_version);
+ tb_info(tb, " Max Port Number: %d\n", sw->max_port_number);
+ tb_info(tb, " Config:\n");
+ tb_info(tb,
+ " Upstream Port Number: %d Depth: %d Route String: %#llx Enabled: %d, PlugEventsDelay: %dms\n",
+ sw->upstream_port_number, sw->depth,
+ (((u64) sw->route_hi) << 32) | sw->route_lo,
+ sw->enabled, sw->plug_events_delay);
+ tb_info(tb,
+ " unknown1: %#x unknown4: %#x\n",
+ sw->__unknown1, sw->__unknown4);
+}
+
+/**
+ * reset_switch() - reconfigure route, enable and send TB_CFG_PKG_RESET
+ *
+ * Return: Returns 0 on success or an error code on failure.
+ */
+int tb_switch_reset(struct tb *tb, u64 route)
+{
+ struct tb_cfg_result res;
+ struct tb_regs_switch_header header = {
+ header.route_hi = route >> 32,
+ header.route_lo = route,
+ header.enabled = true,
+ };
+ tb_info(tb, "resetting switch at %llx\n", route);
+ res.err = tb_cfg_write(tb->ctl, ((u32 *) &header) + 2, route,
+ 0, 2, 2, 2);
+ if (res.err)
+ return res.err;
+ res = tb_cfg_reset(tb->ctl, route, TB_CFG_DEFAULT_TIMEOUT);
+ if (res.err > 0)
+ return -EIO;
+ return res.err;
+}
+
+struct tb_switch *get_switch_at_route(struct tb_switch *sw, u64 route)
+{
+ u8 next_port = route; /*
+ * Routes use a stride of 8 bits,
+ * eventhough a port index has 6 bits at most.
+ * */
+ if (route == 0)
+ return sw;
+ if (next_port > sw->config.max_port_number)
+ return NULL;
+ if (tb_is_upstream_port(&sw->ports[next_port]))
+ return NULL;
+ if (!sw->ports[next_port].remote)
+ return NULL;
+ return get_switch_at_route(sw->ports[next_port].remote->sw,
+ route >> TB_ROUTE_SHIFT);
+}
+
+/**
+ * tb_plug_events_active() - enable/disable plug events on a switch
+ *
+ * Also configures a sane plug_events_delay of 255ms.
+ *
+ * Return: Returns 0 on success or an error code on failure.
+ */
+static int tb_plug_events_active(struct tb_switch *sw, bool active)
+{
+ u32 data;
+ int res;
+
+ sw->config.plug_events_delay = 0xff;
+ res = tb_sw_write(sw, ((u32 *) &sw->config) + 4, TB_CFG_SWITCH, 4, 1);
+ if (res)
+ return res;
+
+ res = tb_sw_read(sw, &data, TB_CFG_SWITCH, sw->cap_plug_events + 1, 1);
+ if (res)
+ return res;
+
+ if (active) {
+ data = data & 0xFFFFFF83;
+ switch (sw->config.device_id) {
+ case 0x1513:
+ case 0x151a:
+ case 0x1549:
+ break;
+ default:
+ data |= 4;
+ }
+ } else {
+ data = data | 0x7c;
+ }
+ return tb_sw_write(sw, &data, TB_CFG_SWITCH,
+ sw->cap_plug_events + 1, 1);
+}
+
+
+/**
+ * tb_switch_free() - free a tb_switch and all downstream switches
+ */
+void tb_switch_free(struct tb_switch *sw)
+{
+ int i;
+ /* port 0 is the switch itself and never has a remote */
+ for (i = 1; i <= sw->config.max_port_number; i++) {
+ if (tb_is_upstream_port(&sw->ports[i]))
+ continue;
+ if (sw->ports[i].remote)
+ tb_switch_free(sw->ports[i].remote->sw);
+ sw->ports[i].remote = NULL;
+ }
+
+ if (!sw->is_unplugged)
+ tb_plug_events_active(sw, false);
+
+ kfree(sw->ports);
+ kfree(sw->drom);
+ kfree(sw);
+}
+
+/**
+ * tb_switch_alloc() - allocate and initialize a switch
+ *
+ * Return: Returns a NULL on failure.
+ */
+struct tb_switch *tb_switch_alloc(struct tb *tb, u64 route)
+{
+ int i;
+ int cap;
+ struct tb_switch *sw;
+ int upstream_port = tb_cfg_get_upstream_port(tb->ctl, route);
+ if (upstream_port < 0)
+ return NULL;
+
+ sw = kzalloc(sizeof(*sw), GFP_KERNEL);
+ if (!sw)
+ return NULL;
+
+ sw->tb = tb;
+ if (tb_cfg_read(tb->ctl, &sw->config, route, 0, 2, 0, 5))
+ goto err;
+ tb_info(tb,
+ "initializing Switch at %#llx (depth: %d, up port: %d)\n",
+ route, tb_route_length(route), upstream_port);
+ tb_info(tb, "old switch config:\n");
+ tb_dump_switch(tb, &sw->config);
+
+ /* configure switch */
+ sw->config.upstream_port_number = upstream_port;
+ sw->config.depth = tb_route_length(route);
+ sw->config.route_lo = route;
+ sw->config.route_hi = route >> 32;
+ sw->config.enabled = 1;
+ /* from here on we may use the tb_sw_* functions & macros */
+
+ if (sw->config.vendor_id != 0x8086)
+ tb_sw_warn(sw, "unknown switch vendor id %#x\n",
+ sw->config.vendor_id);
+
+ if (sw->config.device_id != 0x1547 && sw->config.device_id != 0x1549)
+ tb_sw_warn(sw, "unsupported switch device id %#x\n",
+ sw->config.device_id);
+
+ /* upload configuration */
+ if (tb_sw_write(sw, 1 + (u32 *) &sw->config, TB_CFG_SWITCH, 1, 3))
+ goto err;
+
+ /* initialize ports */
+ sw->ports = kcalloc(sw->config.max_port_number + 1, sizeof(*sw->ports),
+ GFP_KERNEL);
+ if (!sw->ports)
+ goto err;
+
+ for (i = 0; i <= sw->config.max_port_number; i++) {
+ /* minimum setup for tb_find_cap and tb_drom_read to work */
+ sw->ports[i].sw = sw;
+ sw->ports[i].port = i;
+ }
+
+ cap = tb_find_cap(&sw->ports[0], TB_CFG_SWITCH, TB_CAP_PLUG_EVENTS);
+ if (cap < 0) {
+ tb_sw_warn(sw, "cannot find TB_CAP_PLUG_EVENTS aborting\n");
+ goto err;
+ }
+ sw->cap_plug_events = cap;
+
+ /* read drom */
+ if (tb_drom_read(sw))
+ tb_sw_warn(sw, "tb_eeprom_read_rom failed, continuing\n");
+ tb_sw_info(sw, "uid: %#llx\n", sw->uid);
+
+ for (i = 0; i <= sw->config.max_port_number; i++) {
+ if (sw->ports[i].disabled) {
+ tb_port_info(&sw->ports[i], "disabled by eeprom\n");
+ continue;
+ }
+ if (tb_init_port(&sw->ports[i]))
+ goto err;
+ }
+
+ /* TODO: I2C, IECS, link controller */
+
+ if (tb_plug_events_active(sw, true))
+ goto err;
+
+ return sw;
+err:
+ kfree(sw->ports);
+ kfree(sw->drom);
+ kfree(sw);
+ return NULL;
+}
+
+/**
+ * tb_sw_set_unpplugged() - set is_unplugged on switch and downstream switches
+ */
+void tb_sw_set_unpplugged(struct tb_switch *sw)
+{
+ int i;
+ if (sw == sw->tb->root_switch) {
+ tb_sw_WARN(sw, "cannot unplug root switch\n");
+ return;
+ }
+ if (sw->is_unplugged) {
+ tb_sw_WARN(sw, "is_unplugged already set\n");
+ return;
+ }
+ sw->is_unplugged = true;
+ for (i = 0; i <= sw->config.max_port_number; i++) {
+ if (!tb_is_upstream_port(&sw->ports[i]) && sw->ports[i].remote)
+ tb_sw_set_unpplugged(sw->ports[i].remote->sw);
+ }
+}
+
+int tb_switch_resume(struct tb_switch *sw)
+{
+ int i, err;
+ u64 uid;
+ tb_sw_info(sw, "resuming switch\n");
+
+ err = tb_drom_read_uid_only(sw, &uid);
+ if (err) {
+ tb_sw_warn(sw, "uid read failed\n");
+ return err;
+ }
+ if (sw->uid != uid) {
+ tb_sw_info(sw,
+ "changed while suspended (uid %#llx -> %#llx)\n",
+ sw->uid, uid);
+ return -ENODEV;
+ }
+
+ /* upload configuration */
+ err = tb_sw_write(sw, 1 + (u32 *) &sw->config, TB_CFG_SWITCH, 1, 3);
+ if (err)
+ return err;
+
+ err = tb_plug_events_active(sw, true);
+ if (err)
+ return err;
+
+ /* check for surviving downstream switches */
+ for (i = 1; i <= sw->config.max_port_number; i++) {
+ struct tb_port *port = &sw->ports[i];
+ if (tb_is_upstream_port(port))
+ continue;
+ if (!port->remote)
+ continue;
+ if (tb_wait_for_port(port, true) <= 0
+ || tb_switch_resume(port->remote->sw)) {
+ tb_port_warn(port,
+ "lost during suspend, disconnecting\n");
+ tb_sw_set_unpplugged(port->remote->sw);
+ }
+ }
+ return 0;
+}
+
+void tb_switch_suspend(struct tb_switch *sw)
+{
+ int i, err;
+ err = tb_plug_events_active(sw, false);
+ if (err)
+ return;
+
+ for (i = 1; i <= sw->config.max_port_number; i++) {
+ if (!tb_is_upstream_port(&sw->ports[i]) && sw->ports[i].remote)
+ tb_switch_suspend(sw->ports[i].remote->sw);
+ }
+ /*
+ * TODO: invoke tb_cfg_prepare_to_sleep here? does not seem to have any
+ * effect?
+ */
+}