- 根目录:
- drivers
- thunderbolt
- switch.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_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?
*/
}