linux/drivers/thunderbolt/switch.c
Bernat, Yehezkel e545f0d8a5 thunderbolt: Allow clearing the key
If secure authentication of a devices fails, either because the device
already has another key uploaded, or there is some other error sending
challenge to the device, and the user only wants to approve the device
just once (without a new key being uploaded to the device) the current
implementation does not allow this because the key cannot be cleared
once set even if we allow it to be changed.

Make this scenario possible and allow clearing the key by writing
empty string to the key sysfs file.

Signed-off-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28 16:21:32 +02:00

1545 lines
35 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/idr.h>
#include <linux/nvmem-provider.h>
#include <linux/sizes.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include "tb.h"
/* Switch authorization from userspace is serialized by this lock */
static DEFINE_MUTEX(switch_lock);
/* Switch NVM support */
#define NVM_DEVID 0x05
#define NVM_VERSION 0x08
#define NVM_CSS 0x10
#define NVM_FLASH_SIZE 0x45
#define NVM_MIN_SIZE SZ_32K
#define NVM_MAX_SIZE SZ_512K
static DEFINE_IDA(nvm_ida);
struct nvm_auth_status {
struct list_head list;
uuid_t uuid;
u32 status;
};
/*
* Hold NVM authentication failure status per switch This information
* needs to stay around even when the switch gets power cycled so we
* keep it separately.
*/
static LIST_HEAD(nvm_auth_status_cache);
static DEFINE_MUTEX(nvm_auth_status_lock);
static struct nvm_auth_status *__nvm_get_auth_status(const struct tb_switch *sw)
{
struct nvm_auth_status *st;
list_for_each_entry(st, &nvm_auth_status_cache, list) {
if (uuid_equal(&st->uuid, sw->uuid))
return st;
}
return NULL;
}
static void nvm_get_auth_status(const struct tb_switch *sw, u32 *status)
{
struct nvm_auth_status *st;
mutex_lock(&nvm_auth_status_lock);
st = __nvm_get_auth_status(sw);
mutex_unlock(&nvm_auth_status_lock);
*status = st ? st->status : 0;
}
static void nvm_set_auth_status(const struct tb_switch *sw, u32 status)
{
struct nvm_auth_status *st;
if (WARN_ON(!sw->uuid))
return;
mutex_lock(&nvm_auth_status_lock);
st = __nvm_get_auth_status(sw);
if (!st) {
st = kzalloc(sizeof(*st), GFP_KERNEL);
if (!st)
goto unlock;
memcpy(&st->uuid, sw->uuid, sizeof(st->uuid));
INIT_LIST_HEAD(&st->list);
list_add_tail(&st->list, &nvm_auth_status_cache);
}
st->status = status;
unlock:
mutex_unlock(&nvm_auth_status_lock);
}
static void nvm_clear_auth_status(const struct tb_switch *sw)
{
struct nvm_auth_status *st;
mutex_lock(&nvm_auth_status_lock);
st = __nvm_get_auth_status(sw);
if (st) {
list_del(&st->list);
kfree(st);
}
mutex_unlock(&nvm_auth_status_lock);
}
static int nvm_validate_and_write(struct tb_switch *sw)
{
unsigned int image_size, hdr_size;
const u8 *buf = sw->nvm->buf;
u16 ds_size;
int ret;
if (!buf)
return -EINVAL;
image_size = sw->nvm->buf_data_size;
if (image_size < NVM_MIN_SIZE || image_size > NVM_MAX_SIZE)
return -EINVAL;
/*
* FARB pointer must point inside the image and must at least
* contain parts of the digital section we will be reading here.
*/
hdr_size = (*(u32 *)buf) & 0xffffff;
if (hdr_size + NVM_DEVID + 2 >= image_size)
return -EINVAL;
/* Digital section start should be aligned to 4k page */
if (!IS_ALIGNED(hdr_size, SZ_4K))
return -EINVAL;
/*
* Read digital section size and check that it also fits inside
* the image.
*/
ds_size = *(u16 *)(buf + hdr_size);
if (ds_size >= image_size)
return -EINVAL;
if (!sw->safe_mode) {
u16 device_id;
/*
* Make sure the device ID in the image matches the one
* we read from the switch config space.
*/
device_id = *(u16 *)(buf + hdr_size + NVM_DEVID);
if (device_id != sw->config.device_id)
return -EINVAL;
if (sw->generation < 3) {
/* Write CSS headers first */
ret = dma_port_flash_write(sw->dma_port,
DMA_PORT_CSS_ADDRESS, buf + NVM_CSS,
DMA_PORT_CSS_MAX_SIZE);
if (ret)
return ret;
}
/* Skip headers in the image */
buf += hdr_size;
image_size -= hdr_size;
}
return dma_port_flash_write(sw->dma_port, 0, buf, image_size);
}
static int nvm_authenticate_host(struct tb_switch *sw)
{
int ret;
/*
* Root switch NVM upgrade requires that we disconnect the
* existing PCIe paths first (in case it is not in safe mode
* already).
*/
if (!sw->safe_mode) {
ret = tb_domain_disconnect_pcie_paths(sw->tb);
if (ret)
return ret;
/*
* The host controller goes away pretty soon after this if
* everything goes well so getting timeout is expected.
*/
ret = dma_port_flash_update_auth(sw->dma_port);
return ret == -ETIMEDOUT ? 0 : ret;
}
/*
* From safe mode we can get out by just power cycling the
* switch.
*/
dma_port_power_cycle(sw->dma_port);
return 0;
}
static int nvm_authenticate_device(struct tb_switch *sw)
{
int ret, retries = 10;
ret = dma_port_flash_update_auth(sw->dma_port);
if (ret && ret != -ETIMEDOUT)
return ret;
/*
* Poll here for the authentication status. It takes some time
* for the device to respond (we get timeout for a while). Once
* we get response the device needs to be power cycled in order
* to the new NVM to be taken into use.
*/
do {
u32 status;
ret = dma_port_flash_update_auth_status(sw->dma_port, &status);
if (ret < 0 && ret != -ETIMEDOUT)
return ret;
if (ret > 0) {
if (status) {
tb_sw_warn(sw, "failed to authenticate NVM\n");
nvm_set_auth_status(sw, status);
}
tb_sw_info(sw, "power cycling the switch now\n");
dma_port_power_cycle(sw->dma_port);
return 0;
}
msleep(500);
} while (--retries);
return -ETIMEDOUT;
}
static int tb_switch_nvm_read(void *priv, unsigned int offset, void *val,
size_t bytes)
{
struct tb_switch *sw = priv;
return dma_port_flash_read(sw->dma_port, offset, val, bytes);
}
static int tb_switch_nvm_write(void *priv, unsigned int offset, void *val,
size_t bytes)
{
struct tb_switch *sw = priv;
int ret = 0;
if (mutex_lock_interruptible(&switch_lock))
return -ERESTARTSYS;
/*
* Since writing the NVM image might require some special steps,
* for example when CSS headers are written, we cache the image
* locally here and handle the special cases when the user asks
* us to authenticate the image.
*/
if (!sw->nvm->buf) {
sw->nvm->buf = vmalloc(NVM_MAX_SIZE);
if (!sw->nvm->buf) {
ret = -ENOMEM;
goto unlock;
}
}
sw->nvm->buf_data_size = offset + bytes;
memcpy(sw->nvm->buf + offset, val, bytes);
unlock:
mutex_unlock(&switch_lock);
return ret;
}
static struct nvmem_device *register_nvmem(struct tb_switch *sw, int id,
size_t size, bool active)
{
struct nvmem_config config;
memset(&config, 0, sizeof(config));
if (active) {
config.name = "nvm_active";
config.reg_read = tb_switch_nvm_read;
config.read_only = true;
} else {
config.name = "nvm_non_active";
config.reg_write = tb_switch_nvm_write;
config.root_only = true;
}
config.id = id;
config.stride = 4;
config.word_size = 4;
config.size = size;
config.dev = &sw->dev;
config.owner = THIS_MODULE;
config.priv = sw;
return nvmem_register(&config);
}
static int tb_switch_nvm_add(struct tb_switch *sw)
{
struct nvmem_device *nvm_dev;
struct tb_switch_nvm *nvm;
u32 val;
int ret;
if (!sw->dma_port)
return 0;
nvm = kzalloc(sizeof(*nvm), GFP_KERNEL);
if (!nvm)
return -ENOMEM;
nvm->id = ida_simple_get(&nvm_ida, 0, 0, GFP_KERNEL);
/*
* If the switch is in safe-mode the only accessible portion of
* the NVM is the non-active one where userspace is expected to
* write new functional NVM.
*/
if (!sw->safe_mode) {
u32 nvm_size, hdr_size;
ret = dma_port_flash_read(sw->dma_port, NVM_FLASH_SIZE, &val,
sizeof(val));
if (ret)
goto err_ida;
hdr_size = sw->generation < 3 ? SZ_8K : SZ_16K;
nvm_size = (SZ_1M << (val & 7)) / 8;
nvm_size = (nvm_size - hdr_size) / 2;
ret = dma_port_flash_read(sw->dma_port, NVM_VERSION, &val,
sizeof(val));
if (ret)
goto err_ida;
nvm->major = val >> 16;
nvm->minor = val >> 8;
nvm_dev = register_nvmem(sw, nvm->id, nvm_size, true);
if (IS_ERR(nvm_dev)) {
ret = PTR_ERR(nvm_dev);
goto err_ida;
}
nvm->active = nvm_dev;
}
nvm_dev = register_nvmem(sw, nvm->id, NVM_MAX_SIZE, false);
if (IS_ERR(nvm_dev)) {
ret = PTR_ERR(nvm_dev);
goto err_nvm_active;
}
nvm->non_active = nvm_dev;
mutex_lock(&switch_lock);
sw->nvm = nvm;
mutex_unlock(&switch_lock);
return 0;
err_nvm_active:
if (nvm->active)
nvmem_unregister(nvm->active);
err_ida:
ida_simple_remove(&nvm_ida, nvm->id);
kfree(nvm);
return ret;
}
static void tb_switch_nvm_remove(struct tb_switch *sw)
{
struct tb_switch_nvm *nvm;
mutex_lock(&switch_lock);
nvm = sw->nvm;
sw->nvm = NULL;
mutex_unlock(&switch_lock);
if (!nvm)
return;
/* Remove authentication status in case the switch is unplugged */
if (!nvm->authenticating)
nvm_clear_auth_status(sw);
nvmem_unregister(nvm->non_active);
if (nvm->active)
nvmem_unregister(nvm->active);
ida_simple_remove(&nvm_ida, nvm->id);
vfree(nvm->buf);
kfree(nvm);
}
/* 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 authorized_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct tb_switch *sw = tb_to_switch(dev);
return sprintf(buf, "%u\n", sw->authorized);
}
static int tb_switch_set_authorized(struct tb_switch *sw, unsigned int val)
{
int ret = -EINVAL;
if (mutex_lock_interruptible(&switch_lock))
return -ERESTARTSYS;
if (sw->authorized)
goto unlock;
switch (val) {
/* Approve switch */
case 1:
if (sw->key)
ret = tb_domain_approve_switch_key(sw->tb, sw);
else
ret = tb_domain_approve_switch(sw->tb, sw);
break;
/* Challenge switch */
case 2:
if (sw->key)
ret = tb_domain_challenge_switch_key(sw->tb, sw);
break;
default:
break;
}
if (!ret) {
sw->authorized = val;
/* Notify status change to the userspace */
kobject_uevent(&sw->dev.kobj, KOBJ_CHANGE);
}
unlock:
mutex_unlock(&switch_lock);
return ret;
}
static ssize_t authorized_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct tb_switch *sw = tb_to_switch(dev);
unsigned int val;
ssize_t ret;
ret = kstrtouint(buf, 0, &val);
if (ret)
return ret;
if (val > 2)
return -EINVAL;
ret = tb_switch_set_authorized(sw, val);
return ret ? ret : count;
}
static DEVICE_ATTR_RW(authorized);
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 key_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct tb_switch *sw = tb_to_switch(dev);
ssize_t ret;
if (mutex_lock_interruptible(&switch_lock))
return -ERESTARTSYS;
if (sw->key)
ret = sprintf(buf, "%*phN\n", TB_SWITCH_KEY_SIZE, sw->key);
else
ret = sprintf(buf, "\n");
mutex_unlock(&switch_lock);
return ret;
}
static ssize_t key_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct tb_switch *sw = tb_to_switch(dev);
u8 key[TB_SWITCH_KEY_SIZE];
ssize_t ret = count;
bool clear = false;
if (!strcmp(buf, "\n"))
clear = true;
else if (hex2bin(key, buf, sizeof(key)))
return -EINVAL;
if (mutex_lock_interruptible(&switch_lock))
return -ERESTARTSYS;
if (sw->authorized) {
ret = -EBUSY;
} else {
kfree(sw->key);
if (clear) {
sw->key = NULL;
} else {
sw->key = kmemdup(key, sizeof(key), GFP_KERNEL);
if (!sw->key)
ret = -ENOMEM;
}
}
mutex_unlock(&switch_lock);
return ret;
}
static DEVICE_ATTR(key, 0600, key_show, key_store);
static ssize_t nvm_authenticate_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct tb_switch *sw = tb_to_switch(dev);
u32 status;
nvm_get_auth_status(sw, &status);
return sprintf(buf, "%#x\n", status);
}
static ssize_t nvm_authenticate_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct tb_switch *sw = tb_to_switch(dev);
bool val;
int ret;
if (mutex_lock_interruptible(&switch_lock))
return -ERESTARTSYS;
/* If NVMem devices are not yet added */
if (!sw->nvm) {
ret = -EAGAIN;
goto exit_unlock;
}
ret = kstrtobool(buf, &val);
if (ret)
goto exit_unlock;
/* Always clear the authentication status */
nvm_clear_auth_status(sw);
if (val) {
ret = nvm_validate_and_write(sw);
if (ret)
goto exit_unlock;
sw->nvm->authenticating = true;
if (!tb_route(sw))
ret = nvm_authenticate_host(sw);
else
ret = nvm_authenticate_device(sw);
}
exit_unlock:
mutex_unlock(&switch_lock);
if (ret)
return ret;
return count;
}
static DEVICE_ATTR_RW(nvm_authenticate);
static ssize_t nvm_version_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct tb_switch *sw = tb_to_switch(dev);
int ret;
if (mutex_lock_interruptible(&switch_lock))
return -ERESTARTSYS;
if (sw->safe_mode)
ret = -ENODATA;
else if (!sw->nvm)
ret = -EAGAIN;
else
ret = sprintf(buf, "%x.%x\n", sw->nvm->major, sw->nvm->minor);
mutex_unlock(&switch_lock);
return ret;
}
static DEVICE_ATTR_RO(nvm_version);
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_authorized.attr,
&dev_attr_device.attr,
&dev_attr_device_name.attr,
&dev_attr_key.attr,
&dev_attr_nvm_authenticate.attr,
&dev_attr_nvm_version.attr,
&dev_attr_vendor.attr,
&dev_attr_vendor_name.attr,
&dev_attr_unique_id.attr,
NULL,
};
static umode_t switch_attr_is_visible(struct kobject *kobj,
struct attribute *attr, int n)
{
struct device *dev = container_of(kobj, struct device, kobj);
struct tb_switch *sw = tb_to_switch(dev);
if (attr == &dev_attr_key.attr) {
if (tb_route(sw) &&
sw->tb->security_level == TB_SECURITY_SECURE &&
sw->security_level == TB_SECURITY_SECURE)
return attr->mode;
return 0;
} else if (attr == &dev_attr_nvm_authenticate.attr ||
attr == &dev_attr_nvm_version.attr) {
if (sw->dma_port)
return attr->mode;
return 0;
}
return sw->safe_mode ? 0 : attr->mode;
}
static struct attribute_group switch_group = {
.is_visible = switch_attr_is_visible,
.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);
dma_port_free(sw->dma_port);
kfree(sw->uuid);
kfree(sw->device_name);
kfree(sw->vendor_name);
kfree(sw->ports);
kfree(sw->drom);
kfree(sw->key);
kfree(sw);
}
struct device_type tb_switch_type = {
.name = "thunderbolt_device",
.release = tb_switch_release,
};
static int tb_switch_get_generation(struct tb_switch *sw)
{
switch (sw->config.device_id) {
case PCI_DEVICE_ID_INTEL_LIGHT_RIDGE:
case PCI_DEVICE_ID_INTEL_EAGLE_RIDGE:
case PCI_DEVICE_ID_INTEL_LIGHT_PEAK:
case PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_2C:
case PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C:
case PCI_DEVICE_ID_INTEL_PORT_RIDGE:
case PCI_DEVICE_ID_INTEL_REDWOOD_RIDGE_2C_BRIDGE:
case PCI_DEVICE_ID_INTEL_REDWOOD_RIDGE_4C_BRIDGE:
return 1;
case PCI_DEVICE_ID_INTEL_WIN_RIDGE_2C_BRIDGE:
case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_2C_BRIDGE:
case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_4C_BRIDGE:
return 2;
case PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_LP_BRIDGE:
case PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_2C_BRIDGE:
case PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_4C_BRIDGE:
case PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_2C_BRIDGE:
case PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_4C_BRIDGE:
return 3;
default:
/*
* For unknown switches assume generation to be 1 to be
* on the safe side.
*/
tb_sw_warn(sw, "unsupported switch device id %#x\n",
sw->config.device_id);
return 1;
}
}
/**
* 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;
}
sw->generation = tb_switch_get_generation(sw);
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;
/* Root switch is always authorized */
if (!route)
sw->authorized = true;
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_alloc_safe_mode() - allocate a switch that is in safe mode
* @tb: Pointer to the owning domain
* @parent: Parent device for this switch
* @route: Route string for this switch
*
* This creates a switch in safe mode. This means the switch pretty much
* lacks all capabilities except DMA configuration port before it is
* flashed with a valid NVM firmware.
*
* The returned switch must 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_safe_mode(struct tb *tb, struct device *parent, u64 route)
{
struct tb_switch *sw;
sw = kzalloc(sizeof(*sw), GFP_KERNEL);
if (!sw)
return NULL;
sw->tb = tb;
sw->config.depth = tb_route_length(route);
sw->config.route_hi = upper_32_bits(route);
sw->config.route_lo = lower_32_bits(route);
sw->safe_mode = true;
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;
}
/**
* 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);
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);
}
static int tb_switch_add_dma_port(struct tb_switch *sw)
{
u32 status;
int ret;
switch (sw->generation) {
case 3:
break;
case 2:
/* Only root switch can be upgraded */
if (tb_route(sw))
return 0;
break;
default:
/*
* DMA port is the only thing available when the switch
* is in safe mode.
*/
if (!sw->safe_mode)
return 0;
break;
}
if (sw->no_nvm_upgrade)
return 0;
sw->dma_port = dma_port_alloc(sw);
if (!sw->dma_port)
return 0;
/*
* Check status of the previous flash authentication. If there
* is one we need to power cycle the switch in any case to make
* it functional again.
*/
ret = dma_port_flash_update_auth_status(sw->dma_port, &status);
if (ret <= 0)
return ret;
if (status) {
tb_sw_info(sw, "switch flash authentication failed\n");
tb_switch_set_uuid(sw);
nvm_set_auth_status(sw, status);
}
tb_sw_info(sw, "power cycling the switch now\n");
dma_port_power_cycle(sw->dma_port);
/*
* We return error here which causes the switch adding failure.
* It should appear back after power cycle is complete.
*/
return -ESHUTDOWN;
}
/**
* 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;
/*
* Initialize DMA control port now before we read DROM. Recent
* host controllers have more complete DROM on NVM that includes
* vendor and model identification strings which we then expose
* to the userspace. NVM can be accessed through DMA
* configuration based mailbox.
*/
ret = tb_switch_add_dma_port(sw);
if (ret)
return ret;
if (!sw->safe_mode) {
/* 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;
}
}
ret = device_add(&sw->dev);
if (ret)
return ret;
ret = tb_switch_nvm_add(sw);
if (ret)
device_del(&sw->dev);
return ret;
}
/**
* 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);
tb_switch_nvm_remove(sw);
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?
*/
}
struct tb_sw_lookup {
struct tb *tb;
u8 link;
u8 depth;
const uuid_t *uuid;
};
static int tb_switch_match(struct device *dev, void *data)
{
struct tb_switch *sw = tb_to_switch(dev);
struct tb_sw_lookup *lookup = data;
if (!sw)
return 0;
if (sw->tb != lookup->tb)
return 0;
if (lookup->uuid)
return !memcmp(sw->uuid, lookup->uuid, sizeof(*lookup->uuid));
/* Root switch is matched only by depth */
if (!lookup->depth)
return !sw->depth;
return sw->link == lookup->link && sw->depth == lookup->depth;
}
/**
* tb_switch_find_by_link_depth() - Find switch by link and depth
* @tb: Domain the switch belongs
* @link: Link number the switch is connected
* @depth: Depth of the switch in link
*
* Returned switch has reference count increased so the caller needs to
* call tb_switch_put() when done with the switch.
*/
struct tb_switch *tb_switch_find_by_link_depth(struct tb *tb, u8 link, u8 depth)
{
struct tb_sw_lookup lookup;
struct device *dev;
memset(&lookup, 0, sizeof(lookup));
lookup.tb = tb;
lookup.link = link;
lookup.depth = depth;
dev = bus_find_device(&tb_bus_type, NULL, &lookup, tb_switch_match);
if (dev)
return tb_to_switch(dev);
return NULL;
}
/**
* tb_switch_find_by_link_depth() - Find switch by UUID
* @tb: Domain the switch belongs
* @uuid: UUID to look for
*
* Returned switch has reference count increased so the caller needs to
* call tb_switch_put() when done with the switch.
*/
struct tb_switch *tb_switch_find_by_uuid(struct tb *tb, const uuid_t *uuid)
{
struct tb_sw_lookup lookup;
struct device *dev;
memset(&lookup, 0, sizeof(lookup));
lookup.tb = tb;
lookup.uuid = uuid;
dev = bus_find_device(&tb_bus_type, NULL, &lookup, tb_switch_match);
if (dev)
return tb_to_switch(dev);
return NULL;
}
void tb_switch_exit(void)
{
ida_destroy(&nvm_ida);
}