Commit Graph

6 Commits

Author SHA1 Message Date
Mika Westerberg
2d8ff0b586 thunderbolt: Add support for runtime PM
When Thunderbolt host controller is set to RTD3 mode (Runtime D3) it is
present all the time. Because of this it is important to runtime suspend
the controller whenever possible. In case of ICM we have following rules
which all needs to be true before the host controller can be put to D3:

  - The controller firmware reports to support RTD3
  - All the connected devices announce support for RTD3
  - There is no active XDomain connection

Implement this using standard Linux runtime PM APIs so that when all the
children devices are runtime suspended, the Thunderbolt host controller
PCI device is runtime suspended as well. The ICM firmware then starts
powering down power domains towards RTD3 but it can prevent this if it
detects that there is an active Display Port stream (this is not visible
to the software, though).

The Thunderbolt host controller will be runtime resumed either when
there is a remote wake event (device is connected or disconnected), or
when there is access from userspace that requires hardware access.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-25 10:55:29 +02:00
Radion Mirchevsky
484cb153fe thunderbolt: Add tb_xdomain_find_by_route()
This is needed by the new ICM interface to find xdomains by route string
instead of link and depth.

While there update existing tb_xdomain_find_* functions to use
tb_xdomain_get() instead of open-coding the same.

Signed-off-by: Radion Mirchevsky <radion.mirchevsky@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
2018-03-09 12:54:10 +03:00
Mika Westerberg
a78ec0d4f0 thunderbolt: Drop sequence number check from tb_xdomain_match()
Commit 9a03c3d398 ("thunderbolt: Fix a couple right shifting to zero
bugs") revealed an issue that was previously hidden because we never
actually compared received XDomain message sequence numbers properly.
The idea with these sequence numbers is that the responding host uses
the same sequence number that was in the request packet which we can
then check at the requesting host.

However, testing against macOS it looks like it does not follow this but
instead uses some other logic. Windows driver on the other hand handles
it the same way than Linux.

In order to be able to talk to macOS again, fix this so that we drop the
whole sequence number check. This effectively works exactly the same
than it worked before the aforementioned commit. This also follows the
logic the original P2P networking code used.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-27 12:00:00 +09:00
Dan Carpenter
9a03c3d398 thunderbolt: Fix a couple right shifting to zero bugs
The problematic code looks like this:

	res_seq = res_hdr->xd_hdr.length_sn & TB_XDOMAIN_SN_MASK;
	res_seq >>= TB_XDOMAIN_SN_SHIFT;

TB_XDOMAIN_SN_SHIFT is 27, and right shifting a u8 27 bits is always
going to result in zero.  The fix is to declare these variables as u32.

Fixes: d1ff70241a ("thunderbolt: Add support for XDomain discovery protocol")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-19 13:04:32 +01:00
Mika Westerberg
acb40d8412 thunderbolt: Initialize Thunderbolt bus earlier
The 0day kbuild robot reports following crash:

  BUG: unable to handle kernel NULL pointer dereference at 00000004
  IP: tb_property_find+0xe/0x41
  *pde = 00000000
  Oops: 0000 [#1]
  CPU: 0 PID: 1 Comm: swapper Not tainted 4.14.0-rc1-00741-ge69b6c0 #412
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
  task: 89c80000 task.stack: 89c7c000
  EIP: tb_property_find+0xe/0x41
  EFLAGS: 00210246 CPU: 0
  EAX: 00000000 EBX: 7a368f47 ECX: 00000044 EDX: 7a368f47
  ESI: 8851d340 EDI: 7a368f47 EBP: 89c7df0c ESP: 89c7defc
   DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068
  CR0: 80050033 CR2: 00000004 CR3: 027a2000 CR4: 00000690
  Call Trace:
   tb_register_property_dir+0x49/0xb9
   ? cdc_mbim_driver_init+0x1b/0x1b
   tbnet_init+0x77/0x9f
   ? cdc_mbim_driver_init+0x1b/0x1b
   do_one_initcall+0x7e/0x145
   ? parse_args+0x10c/0x1b3
   ? kernel_init_freeable+0xbe/0x159
   kernel_init_freeable+0xd1/0x159
   ? rest_init+0x110/0x110
   kernel_init+0xd/0xd0
   ret_from_fork+0x19/0x30

The reason is that both Thunderbolt bus and thunderbolt-net are build
into the kernel image, and the latter is linked first because
drivers/net comes before drivers/thunderbolt. Since both use
module_init() thunderbolt-net ends up calling Thunderbolt bus functions
too early triggering the above crash.

Fix this by moving Thunderbolt bus initialization to happen earlier to
make sure all the data structures are ready when Thunderbolt service
drivers are initialized. To be on the safe side also add a check for
properly initialized xdomain_property_dir to tb_register_property_dir().

Reported-by: kernel test robot <fengguang.wu@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-09 10:30:41 -07:00
Mika Westerberg
d1ff70241a thunderbolt: Add support for XDomain discovery protocol
When two hosts are connected over a Thunderbolt cable, there is a
protocol they can use to communicate capabilities supported by the host.
The discovery protocol uses automatically configured control channel
(ring 0) and is build on top of request/response transactions using
special XDomain primitives provided by the Thunderbolt base protocol.

The capabilities consists of a root directory block of basic properties
used for identification of the host, and then there can be zero or more
directories each describing a Thunderbolt service and its capabilities.

Once both sides have discovered what is supported the two hosts can
setup high-speed DMA paths and transfer data to the other side using
whatever protocol was agreed based on the properties. The software
protocol used to communicate which DMA paths to enable is service
specific.

This patch adds support for the XDomain discovery protocol to the
Thunderbolt bus. We model each remote host connection as a Linux XDomain
device. For each Thunderbolt service found supported on the XDomain
device, we create Linux Thunderbolt service device which Thunderbolt
service drivers can then bind to based on the protocol identification
information retrieved from the property directory describing the
service.

This code is based on the work done by Amir Levy and Michael Jamet.

Signed-off-by: Michael Jamet <michael.jamet@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-02 11:24:41 -07:00