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linux-next/drivers/thunderbolt/switch.c
Mika Westerberg 72ee33907b thunderbolt: Read vendor and device name from DROM
The device DROM contains name of the vendor and device among other
things. Extract this information and expose it to the userspace via two
new attributes.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09 11:42:42 +02:00

697 lines
17 KiB
C

/*
* 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_port_find_cap(port, TB_PORT_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;
if (!sw->config.enabled)
return 0;
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 PCI_DEVICE_ID_INTEL_LIGHT_RIDGE:
case PCI_DEVICE_ID_INTEL_EAGLE_RIDGE:
case PCI_DEVICE_ID_INTEL_PORT_RIDGE:
break;
default:
data |= 4;
}
} else {
data = data | 0x7c;
}
return tb_sw_write(sw, &data, TB_CFG_SWITCH,
sw->cap_plug_events + 1, 1);
}
static ssize_t device_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct tb_switch *sw = tb_to_switch(dev);
return sprintf(buf, "%#x\n", sw->device);
}
static DEVICE_ATTR_RO(device);
static ssize_t
device_name_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct tb_switch *sw = tb_to_switch(dev);
return sprintf(buf, "%s\n", sw->device_name ? sw->device_name : "");
}
static DEVICE_ATTR_RO(device_name);
static ssize_t vendor_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct tb_switch *sw = tb_to_switch(dev);
return sprintf(buf, "%#x\n", sw->vendor);
}
static DEVICE_ATTR_RO(vendor);
static ssize_t
vendor_name_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct tb_switch *sw = tb_to_switch(dev);
return sprintf(buf, "%s\n", sw->vendor_name ? sw->vendor_name : "");
}
static DEVICE_ATTR_RO(vendor_name);
static ssize_t unique_id_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct tb_switch *sw = tb_to_switch(dev);
return sprintf(buf, "%pUb\n", sw->uuid);
}
static DEVICE_ATTR_RO(unique_id);
static struct attribute *switch_attrs[] = {
&dev_attr_device.attr,
&dev_attr_device_name.attr,
&dev_attr_vendor.attr,
&dev_attr_vendor_name.attr,
&dev_attr_unique_id.attr,
NULL,
};
static struct attribute_group switch_group = {
.attrs = switch_attrs,
};
static const struct attribute_group *switch_groups[] = {
&switch_group,
NULL,
};
static void tb_switch_release(struct device *dev)
{
struct tb_switch *sw = tb_to_switch(dev);
kfree(sw->uuid);
kfree(sw->device_name);
kfree(sw->vendor_name);
kfree(sw->ports);
kfree(sw->drom);
kfree(sw);
}
struct device_type tb_switch_type = {
.name = "thunderbolt_device",
.release = tb_switch_release,
};
/**
* tb_switch_alloc() - allocate a switch
* @tb: Pointer to the owning domain
* @parent: Parent device for this switch
* @route: Route string for this switch
*
* Allocates and initializes a switch. Will not upload configuration to
* the switch. For that you need to call tb_switch_configure()
* separately. The returned switch should be released by calling
* tb_switch_put().
*
* Return: Pointer to the allocated switch or %NULL in case of failure
*/
struct tb_switch *tb_switch_alloc(struct tb *tb, struct device *parent,
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, TB_CFG_SWITCH, 0, 5))
goto err_free_sw_ports;
tb_info(tb, "current 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 = 0;
/* initialize ports */
sw->ports = kcalloc(sw->config.max_port_number + 1, sizeof(*sw->ports),
GFP_KERNEL);
if (!sw->ports)
goto err_free_sw_ports;
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_switch_find_vse_cap(sw, TB_VSE_CAP_PLUG_EVENTS);
if (cap < 0) {
tb_sw_warn(sw, "cannot find TB_VSE_CAP_PLUG_EVENTS aborting\n");
goto err_free_sw_ports;
}
sw->cap_plug_events = cap;
device_initialize(&sw->dev);
sw->dev.parent = parent;
sw->dev.bus = &tb_bus_type;
sw->dev.type = &tb_switch_type;
sw->dev.groups = switch_groups;
dev_set_name(&sw->dev, "%u-%llx", tb->index, tb_route(sw));
return sw;
err_free_sw_ports:
kfree(sw->ports);
kfree(sw);
return NULL;
}
/**
* tb_switch_configure() - Uploads configuration to the switch
* @sw: Switch to configure
*
* Call this function before the switch is added to the system. It will
* upload configuration to the switch and makes it available for the
* connection manager to use.
*
* Return: %0 in case of success and negative errno in case of failure
*/
int tb_switch_configure(struct tb_switch *sw)
{
struct tb *tb = sw->tb;
u64 route;
int ret;
route = tb_route(sw);
tb_info(tb,
"initializing Switch at %#llx (depth: %d, up port: %d)\n",
route, tb_route_length(route), sw->config.upstream_port_number);
if (sw->config.vendor_id != PCI_VENDOR_ID_INTEL)
tb_sw_warn(sw, "unknown switch vendor id %#x\n",
sw->config.vendor_id);
if (sw->config.device_id != PCI_DEVICE_ID_INTEL_LIGHT_RIDGE &&
sw->config.device_id != PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C &&
sw->config.device_id != PCI_DEVICE_ID_INTEL_PORT_RIDGE &&
sw->config.device_id != PCI_DEVICE_ID_INTEL_FALCON_RIDGE_2C_BRIDGE &&
sw->config.device_id != PCI_DEVICE_ID_INTEL_FALCON_RIDGE_4C_BRIDGE)
tb_sw_warn(sw, "unsupported switch device id %#x\n",
sw->config.device_id);
sw->config.enabled = 1;
/* upload configuration */
ret = tb_sw_write(sw, 1 + (u32 *)&sw->config, TB_CFG_SWITCH, 1, 3);
if (ret)
return ret;
return tb_plug_events_active(sw, true);
}
static void tb_switch_set_uuid(struct tb_switch *sw)
{
u32 uuid[4];
int cap;
if (sw->uuid)
return;
/*
* The newer controllers include fused UUID as part of link
* controller specific registers
*/
cap = tb_switch_find_vse_cap(sw, TB_VSE_CAP_LINK_CONTROLLER);
if (cap > 0) {
tb_sw_read(sw, uuid, TB_CFG_SWITCH, cap + 3, 4);
} else {
/*
* ICM generates UUID based on UID and fills the upper
* two words with ones. This is not strictly following
* UUID format but we want to be compatible with it so
* we do the same here.
*/
uuid[0] = sw->uid & 0xffffffff;
uuid[1] = (sw->uid >> 32) & 0xffffffff;
uuid[2] = 0xffffffff;
uuid[3] = 0xffffffff;
}
sw->uuid = kmemdup(uuid, sizeof(uuid), GFP_KERNEL);
}
/**
* tb_switch_add() - Add a switch to the domain
* @sw: Switch to add
*
* This is the last step in adding switch to the domain. It will read
* identification information from DROM and initializes ports so that
* they can be used to connect other switches. The switch will be
* exposed to the userspace when this function successfully returns. To
* remove and release the switch, call tb_switch_remove().
*
* Return: %0 in case of success and negative errno in case of failure
*/
int tb_switch_add(struct tb_switch *sw)
{
int i, ret;
/* read drom */
ret = tb_drom_read(sw);
if (ret) {
tb_sw_warn(sw, "tb_eeprom_read_rom failed\n");
return ret;
}
tb_sw_info(sw, "uid: %#llx\n", sw->uid);
tb_switch_set_uuid(sw);
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;
}
ret = tb_init_port(&sw->ports[i]);
if (ret)
return ret;
}
return device_add(&sw->dev);
}
/**
* tb_switch_remove() - Remove and release a switch
* @sw: Switch to remove
*
* This will remove the switch from the domain and release it after last
* reference count drops to zero. If there are switches connected below
* this switch, they will be removed as well.
*/
void tb_switch_remove(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_remove(sw->ports[i].remote->sw);
sw->ports[i].remote = NULL;
}
if (!sw->is_unplugged)
tb_plug_events_active(sw, false);
device_unregister(&sw->dev);
}
/**
* tb_sw_set_unplugged() - set is_unplugged on switch and downstream switches
*/
void tb_sw_set_unplugged(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_unplugged(sw->ports[i].remote->sw);
}
}
int tb_switch_resume(struct tb_switch *sw)
{
int i, err;
tb_sw_info(sw, "resuming switch\n");
/*
* Check for UID of the connected switches except for root
* switch which we assume cannot be removed.
*/
if (tb_route(sw)) {
u64 uid;
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_unplugged(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?
*/
}