Some external devices can support completing thunderbolt authentication
when they are unplugged. For this to work though, the link controller must
remain operational.
The only device known to support this right now is the Dell WD19TB, so add
a quirk for this.
Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
This allows userspace to have a shorter period of time that the device
is unusable and to call it at a more convenient time.
For example flushing the image may happen while the user is using the
machine and authenticating/rebooting may happen while logging out.
Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The 32 bit int value 512 is being left shifted and then used in a context
that expects the expression to be a larger unsigned long. There may be
a potential integer overflow, so make 512 a UL before shift to avoid
any such issues.
Addresses-Coverity: ("Uninintentional integer overflow")
Fixes: 3b1d8d577c ("thunderbolt: Implement USB3 bandwidth negotiation routines")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
USB4 spec specifies standard access to retimers (both on-board and
cable) through USB4 port sideband access. This makes it possible to
upgrade their firmware in the same way than we already do with the
routers.
This enumerates on-board retimers under each USB4 port when the link
comes up and adds them to the bus under the router the retimer belongs
to. Retimers are exposed in sysfs with name like <device>:<port>.<index>
where device is the router the retimer belongs to, port is the USB4 port
the retimer is connected to and index is the retimer index under that
port (starting from 1). This applies to the upstream USB4 port as well
so if there is on-board retimer between the port and the router it is
also added accordingly.
At this time we do not add cable retimers but there is no techincal
restriction to do so in the future if needed. It is not clear whether it
makes sense to upgrade their firmwares and at least Thunderbolt 3 cables
it has not been done outside of lab environments.
The sysfs interface is made to follow the router NVM upgrade to make it
easy to extend the existing userspace (fwupd) to handle these as well.
Signed-off-by: Kranthi Kuntala <kranthi.kuntala@intel.com>
Co-developed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
USB4 spec specifies standard set of sideband operations that are send
over the low speed link to access either retimers on the link or the
link parter (the other router). The USB4 retimer spec extends these and
adds operations for retimer NVM upgrade.
This implements the retimer access and NVM upgrade USB4 port sideband
operations which we need for retimer support in the patch that follows.
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>
Especially when accessing retimers over USB4 sideband operations the
possibility to get read errors seems to be higher so make the
usb4_do_read_data() retry a couple of times if it sees any other error
than -ENODEV (device is gone). We can only do this for read side because
it carries the offset as part of metadata (as opposed to writes).
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Currently these functions operate on struct tb_switch but we are going
to need the same functionality with retimers as well so make the two
functions work with an arbitrary object that gets passed as parameter to
the callbacks.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
We are going to reuse some of this functionality to implement retimer
NVM upgrade so move common NVM functionality into its own file. We also
rename the structure from tb_switch_nvm to tb_nvm to make it clear that
it is not just for switches.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
With USB4 Intel is also using its USB-IF ID (0x8087) with the new
devices. The NVM format is the same. Add this to the driver so NVM
upgrade is possible with these devices as well.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
We can test some parts of tunneling, like path allocation without access
to test hardware so add KUnit tests for PCIe, DP and USB3 tunneling.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
USB3 supports both isochronous and non-isochronous traffic. The former
requires guaranteed bandwidth and can take up to 90% of the total
bandwidth. With USB4 USB3 is tunneled over USB4 fabric which means that
we need to make sure there is enough bandwidth allocated for the USB3
tunnels in addition to DisplayPort tunnels.
Whereas DisplayPort bandwidth management is static and done before the
DP tunnel is established, the USB3 bandwidth management is dynamic and
allows increasing and decreasing the allocated bandwidth according to
what is currently consumed. This is done through host router USB3
downstream adapter registers.
This adds USB3 bandwidth management to the software connection manager
so that we always try to allocate maximum bandwidth for DP tunnels and
what is left is allocated for USB3.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
We need to call this from tb.c when we improve the bandwidth management
to take USB3 into account.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Each host router USB3 downstream adapter has a set of registers that are
used to negotiate bandwidth between the connection manager and the
internal xHCI controller. These registers allow dynamic bandwidth
management for USB3 isochronous traffic based on what is actually
consumed vs. allocated at any given time.
Implement these USB3 bandwidth negotiation routines to allow the
software connection manager take advantage of these.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Sometimes it takes longer for DPRX to be set so increase the timeout to
cope with this.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Whereas DisplayPort bandwidth is consumed only in one direction (from DP
IN adapter to DP OUT adapter), USB3 adds separate bandwidth for both
upstream and downstream directions.
For this reason extend the tunnel consumed bandwidth routines to support
both directions and implement this for DP.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Just for symmetry with the usb4_switch_map_usb3_down() make this one
also return ports that are enabled.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
We need to call this on enabled ports in order to find the mapping from
host router USB4 port to a USB 3.x downstream adapter, so make the
function return enabled ports as well.
While there fix parameter alignment in tb_find_usb3_down().
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
USB3 tunneling is possible only over USB4 link so don't create USB3
tunnels if that's not the case.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
USB4 spec allows DP tunneling from any router that has DP IN adapter,
not just from host router. The driver currently only added the DP IN
resources for the host router because Thunderbolt 1, 2 and 3 devices do
not have DP IN adapters. However, USB4 allows device routers to have DP
IN adapter as well so update the driver to add DP IN resources for each
device that has one. One example would be an eGPU enclosure where the
eGPU output is forwarded to DP IN port and then tunneled over the USB4
fabric.
Only limitation we add now is that the DP IN and DP OUT that gets paired
for tunnel creation should both be under the same topology starting from
host router downstream port. In other words we do not create DP tunnels
across host router at this time even though that is possible as well but
it complicates the bandwidth management and there is no real use-case
for this anyway.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
This adds KUnit tests for path walking which is only dependent on
software structures, so no hardware is needed to run these.
We make these available only when both KUnit and the driver itself are
built into the kernel image. The reason for this is that KUnit adds its
own module_init() call in kunit_test_suite() which generates linker
error because the driver does the same in nhi.c. This should be fine for
now because these tests are only meant to run by developers anyway.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Currently we have only supported paths that follow daisy-chain topology
but USB4 also allows to build trees of devices. For this reason increase
maximum path length we use for discovery to be from the lowest level to
the host router and back to the same level.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
If the path is not complete when we do discovery the number of hops may
be less than with the full path. As an example when this can happen is
that user unloads the driver, disconnects the topology, and loads the
driver back. If there is PCIe or USB3 tunnel involved this may happen.
Take this into account in tb_pcie_init_path() and tb_usb3_init_path()
and prevent potential access over array limits.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Add sanity check that given src and dst ports are reachable through path
walk before allocating a path. If they are not then bail out early.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
With USB4, topologies are not limited to daisy-chains anymore so when
calculating how many hops are between two ports we need to walk the
whole path instead.
Add helper function tb_for_each_port_on_path() that can be used to walk
over each port on a path and make tb_path_alloc() to use it.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
USB4 makes it possible to have tree topology of devices connected in the
same way than USB3. This was actually possible in Thunderbolt 1, 2 and 3
as well but all the available devices only had two ports which allows
building only daisy-chains of devices.
With USB4 it is possible for example that there is DP IN adapter as part
of eGPU device router and that should be tunneled over the tree topology
to a DP OUT adapter. This updates the tb_next_port_on_path() to support
such topologies.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The USB3 discovery used wrong indices when tunnel is discovered. It
should use TB_USB3_PATH_DOWN for path that flows downstream and
TB_USB3_PATH_UP when it flows upstream. This should not affect the
functionality but better to fix it.
Fixes: e6f8185857 ("thunderbolt: Add support for USB 3.x tunnels")
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: stable@vger.kernel.org # v5.6+
The end-to-end (E2E) workaround is needed for Falcon Ridge (TBT 2)
controller when E2E is enabled for both ends of the host-to-host
connection. However, we never supported full E2E in the first place so
this code is not necessary at the moment. Further this allows us to use
all available rings for data except ring 0 which is reserved for the
control path.
The complete E2E flow control is explained in the USB4 spec so we may
add it back later if needed but at least the networking driver seems to
work fine without, and the higher level stack, like TCP will retransmit
lost packets anyway.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
NHI (The host interface adapter) is allowed to use HopIDs 1-7 as well so
relax the restriction in tb_port_alloc_hopid() to support this.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
While Intel hardware typically has hop_count (Total Paths in the spec)
12 the USB4 spec allows this to be anything between 1 and 21 so no need
to warn about this. Simply log number of paths at debug level.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
On a systems where the Thunderbolt controller is present all the time
the kernel nodename may not yet set by the userspace when the driver is
loaded. This means when another host is connected it may see the default
"(none)" hostname instead of the system real hostname.
For this reason build the initial XDomain property block only upon first
connect. This should make sure the userspace has had chance to set it up.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Fix the spelling of "specification", and add a missing "the" article.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Here are the large set of USB and PHY driver updates for 5.8-rc1.
Nothing huge, just lots of little things:
- USB gadget fixes and additions all over the place
- new PHY drivers
- PHY driver fixes and updates
- XHCI driver updates
- musb driver updates
- more USB-serial driver ids added
- various USB quirks added
- thunderbolt minor updates and fixes
- typec updates and additions
Full details are in the shortlog.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB/PHY driver updates from Greg KH:
"Here are the large set of USB and PHY driver updates for 5.8-rc1.
Nothing huge, just lots of little things:
- USB gadget fixes and additions all over the place
- new PHY drivers
- PHY driver fixes and updates
- XHCI driver updates
- musb driver updates
- more USB-serial driver ids added
- various USB quirks added
- thunderbolt minor updates and fixes
- typec updates and additions
All of these have been in linux-next for a while with no reported
issues"
* tag 'usb-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (245 commits)
usb: dwc3: meson-g12a: fix USB2 PHY initialization on G12A and A1 SoCs
usb: dwc3: meson-g12a: fix error path when fetching the reset line fails
Revert "dt-bindings: usb: qcom,dwc3: Convert USB DWC3 bindings"
Revert "dt-bindings: usb: qcom,dwc3: Add compatible for SC7180"
Revert "dt-bindings: usb: qcom,dwc3: Introduce interconnect properties for Qualcomm DWC3 driver"
USB: serial: ch341: fix lockup of devices with limited prescaler
USB: serial: ch341: add basis for quirk detection
CDC-ACM: heed quirk also in error handling
USB: serial: option: add Telit LE910C1-EUX compositions
usb: musb: Fix runtime PM imbalance on error
usb: musb: jz4740: Prevent lockup when CONFIG_SMP is set
usb: musb: mediatek: add reset FADDR to zero in reset interrupt handle
usb: musb: use true for 'use_dma'
usb: musb: start session in resume for host port
usb: musb: return -ESHUTDOWN in urb when three-strikes error happened
USB: serial: qcserial: add DW5816e QDL support
thunderbolt: Add trivial .shutdown
usb: dwc3: keystone: Turn on USB3 PHY before controller
dt-bindings: usb: ti,keystone-dwc3.yaml: Add USB3.0 PHY property
dt-bindings: usb: convert keystone-usb.txt to YAML
...
This adds support for Intel Tiger Lake Thunderbolt controller using
firmware based connection manager. In addition the driver can now be
built on non-x86 architectures as well. Then there are a couple of
commits that make the driver work across kexec, replace a zero length
array with flexible one, and revert one change that is not needed
anymore because of NVMem subsystem improvements.
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Merge tag 'thunderbolt-for-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/westeri/thunderbolt into usb-next
Mika writes:
thunderbolt: Changes for v5.8 merge window
This adds support for Intel Tiger Lake Thunderbolt controller using
firmware based connection manager. In addition the driver can now be
built on non-x86 architectures as well. Then there are a couple of
commits that make the driver work across kexec, replace a zero length
array with flexible one, and revert one change that is not needed
anymore because of NVMem subsystem improvements.
* tag 'thunderbolt-for-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/westeri/thunderbolt:
thunderbolt: Add trivial .shutdown
thunderbolt: Update Kconfig to allow building on other architectures.
thunderbolt: Replace zero-length array with flexible-array
thunderbolt: Add support for Intel Tiger Lake
Revert "thunderbolt: Prevent crash if non-active NVMem file is read"
On my machine, a kexec with this driver loaded in the old kernel causes
a very long delay on boot in the kexec'ed kernel, most likely due to
unclean shutdown prior to that.
Unloading thunderbolt driver prior to kexec allows kexec to work as fast
as regular kernel boot, as well as adding this .shutdown pointer.
Shutting a device prior to the shutdown completely is always a good idea
IMHO to help with kexec, and this one-liner patch implements it.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Previously we used pcie_find_root_port() to find a Root Port from a PCIe
device and pci_find_pcie_root_port() to find a Root Port from a
Conventional PCI device.
Unify the two functions and use pcie_find_root_port() to find a Root Port
from either a Conventional PCI device or a PCIe device. Then there is no
need to distinguish the type of the device.
Link: https://lore.kernel.org/r/1589019568-5216-1-git-send-email-yangyicong@hisilicon.com
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> # thunderbolt
Thunderbolt 3 and USB4 shouldn't be x86 only.
Tested on a SolidRun HoneyComb (ARM Cortex-A72) with a
Gigabyte Titan Ridge Thunderbolt 3 PCIe card (JHL7540).
Signed-off-by: David Manouchehri <david.manouchehri@riseup.net>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The function misses checking return value of tb_sw_read() before it
accesses the value that was read. Fix this by checking the return value
first.
Fixes: b04079837b ("thunderbolt: Add initial support for USB4")
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkelshb@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tiger Lake integrated Thunderbolt/USB4 controller is quite close to
Intel Ice Lake. By default it is still using firmware based connection
manager so we can use most of the Ice Lake flows in Tiger Lake as well.
We check if the firmware connection manager is running and in that case
use it, otherwise use the software based connection manager.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Yehezkel Bernat <yehezkelshb@gmail.com>
This reverts commit 03cd45d2e2.
Commit 664f054938 ("nvmem: core: use is_bin_visible for permissions")
incidentally adds support for write-only nvmem. Hence, this workaround
is no longer required, so drop it.
Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
- A couple of commits that make the driver to use flexible-array member
instead of zero-length array extension. This allows compiler to issue a
warning if the flexible array is not the last member of a structure.
- Use scnprintf() instead of snprintf() to avoid potential buffer
overflow.
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Merge tag 'thunderbolt-for-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/westeri/thunderbolt into usb-next
Mika writes:
thunderbolt: Changes for v5.7 merge window
- A couple of commits that make the driver to use flexible-array member
instead of zero-length array extension. This allows compiler to issue a
warning if the flexible array is not the last member of a structure.
- Use scnprintf() instead of snprintf() to avoid potential buffer
overflow.
* tag 'thunderbolt-for-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/westeri/thunderbolt:
thunderbolt: Use scnprintf() for avoiding potential buffer overflow
thunderbolt: icm: Replace zero-length array with flexible-array member
thunderbolt: eeprom: Replace zero-length array with flexible-array member
Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit. Fix it by replacing with scnprintf().
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
This function is type bool, and it's supposed to return true on success.
Unfortunately, this path takes negative error codes and casts them to
bool (true) so it's treated as success instead of failure.
Fixes: 91c0c12080 ("thunderbolt: Add support for lane bonding")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertenly introduced[3] to the codebase from now on.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertenly introduced[3] to the codebase from now on.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Stephen Rothwell
Wei Yongjun
Mario Limonciello
Colin Ian King
Kranthi Kuntala
Rajmohan Mani
Mika Westerberg
Geert Uytterhoeven
Linus Torvalds
Greg Kroah-Hartman
Maxim Levitsky
Yicong Yang
David Manouchehri
Nicholas Johnson
Takashi Iwai
Dan Carpenter
Gustavo A. R. Silva