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thunderbolt: Add support for retimer NVM upgrade when there is no link

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With help from platform firmware (ACPI) it is possible to power on
retimers even when there is no USB4 link (e.g nothing is connected to
the USB4 ports). This allows us to bring the USB4 sideband up so that we
can access retimers and upgrade their NVM firmware.

If the platform has support for this, we expose two additional
attributes under USB4 ports: offline and rescan. These can be used to
bring the port offline, rescan for the retimers and put the port online
again. The retimer NVM upgrade itself works the same way than with cable
connected.

Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com>
Co-developed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Rajmohan Mani
2021-04-01 18:42:38 +03:00
committed by Mika Westerberg
parent 3406de7cc2
commit 3fb10ea4ce
7 changed files with 277 additions and 28 deletions
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48
drivers/thunderbolt/switch.c
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@@ -1153,6 +1153,33 @@ static int tb_port_start_lane_initialization(struct tb_port *port)
return ret == -EINVAL ? 0 : ret;
}
/*
* Returns true if the port had something (router, XDomain) connected
* before suspend.
*/
static bool tb_port_resume(struct tb_port *port)
{
bool has_remote = tb_port_has_remote(port);
if (port->usb4) {
usb4_port_device_resume(port->usb4);
} else if (!has_remote) {
/*
* For disconnected downstream lane adapters start lane
* initialization now so we detect future connects.
*
* For XDomain start the lane initialzation now so the
* link gets re-established.
*
* This is only needed for non-USB4 ports.
*/
if (!tb_is_upstream_port(port) || port->xdomain)
tb_port_start_lane_initialization(port);
}
return has_remote || port->xdomain;
}
/**
* tb_port_is_enabled() - Is the adapter port enabled
* @port: Port to check
@@ -2915,22 +2942,11 @@ int tb_switch_resume(struct tb_switch *sw)
/* check for surviving downstream switches */
tb_switch_for_each_port(sw, port) {
if (!tb_port_has_remote(port) && !port->xdomain) {
/*
* For disconnected downstream lane adapters
* start lane initialization now so we detect
* future connects.
*/
if (!tb_is_upstream_port(port) && tb_port_is_null(port))
tb_port_start_lane_initialization(port);
if (!tb_port_is_null(port))
continue;
if (!tb_port_resume(port))
continue;
} else if (port->xdomain) {
/*
* Start lane initialization for XDomain so the
* link gets re-established.
*/
tb_port_start_lane_initialization(port);
}
if (tb_wait_for_port(port, true) <= 0) {
tb_port_warn(port,
@@ -2939,7 +2955,7 @@ int tb_switch_resume(struct tb_switch *sw)
tb_sw_set_unplugged(port->remote->sw);
else if (port->xdomain)
port->xdomain->is_unplugged = true;
} else if (tb_port_has_remote(port) || port->xdomain) {
} else {
/*
* Always unlock the port so the downstream
* switch/domain is accessible.