linux-toradex.git/drivers/base/core.c, branch v5.11-rc3 Linux kernel for Apalis and Colibri modules device property: add description of fwnode cases 2021-01-07T16:55:55+00:00 Bard Liao yung-chuan.liao@linux.intel.com 2021-01-05T09:11:46+00:00 3f7bddaf5d5a83aa2eb1e6d72db221d3ec43c813 There are only four valid fwnode cases which are - primary --> secondary --> -ENODEV - primary --> NULL - secondary --> -ENODEV - NULL dev->fwnode should be converted between the 4 cases above no matter how/when set_primary_fwnode() and set_secondary_fwnode() are called. Describe it in the code so people will keep it in mind. Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> [ rjw: Comment edit ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
There are only four valid fwnode cases which are
- primary --> secondary --> -ENODEV
- primary --> NULL
- secondary --> -ENODEV
- NULL

dev->fwnode should be converted between the 4 cases above no matter
how/when set_primary_fwnode() and set_secondary_fwnode() are called.
Describe it in the code so people will keep it in mind.

Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
[ rjw: Comment edit ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Revert "device property: Keep secondary firmware node secondary by type" 2021-01-07T16:55:55+00:00 Bard Liao yung-chuan.liao@linux.intel.com 2021-01-05T09:11:45+00:00 47f4469970d8861bc06d2d4d45ac8200ff07c693 While commit d5dcce0c414f ("device property: Keep secondary firmware node secondary by type") describes everything correct in its commit message, the change it made does the opposite and original commit c15e1bdda436 ("device property: Fix the secondary firmware node handling in set_primary_fwnode()") was fully correct. Revert the former one here and improve documentation in the next patch. Fixes: d5dcce0c414f ("device property: Keep secondary firmware node secondary by type") Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Cc: 5.10+ <stable@vger.kernel.org> # 5.10+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
While commit d5dcce0c414f ("device property: Keep secondary firmware
node secondary by type") describes everything correct in its commit
message, the change it made does the opposite and original commit
c15e1bdda436 ("device property: Fix the secondary firmware node handling
in set_primary_fwnode()") was fully correct.

Revert the former one here and improve documentation in the next patch.

Fixes: d5dcce0c414f ("device property: Keep secondary firmware node secondary by type")
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: 5.10+ <stable@vger.kernel.org> # 5.10+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
driver core: Fix a couple of typos 2020-12-09T18:29:47+00:00 Thierry Reding treding@nvidia.com 2020-11-27T10:46:30+00:00 d475f8ea98a039e51d27f5557dc17333cf8a52f6 These were just some minor typos that have crept in recently and are easily fixed. Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Thierry Reding <treding@nvidia.com> Link: https://lore.kernel.org/r/20201127104630.1839171-1-thierry.reding@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
These were just some minor typos that have crept in recently and are
easily fixed.

Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20201127104630.1839171-1-thierry.reding@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
driver core: Delete pointless parameter in fwnode_operations.add_links 2020-12-09T18:14:48+00:00 Saravana Kannan saravanak@google.com 2020-11-21T02:02:32+00:00 2d09e6eb4a6f20273959f4905ccf009da8c64c7a The struct device input to add_links() is not used for anything. So delete it. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-18-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
The struct device input to add_links() is not used for anything. So
delete it.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20201121020232.908850-18-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
driver core: Refactor fw_devlink feature 2020-12-09T18:14:48+00:00 Saravana Kannan saravanak@google.com 2020-11-21T02:02:31+00:00 f9aa460672c9c56896cdc12a521159e3e67000ba The current implementation of fw_devlink is very inefficient because it tries to get away without creating fwnode links in the name of saving memory usage. Past attempts to optimize runtime at the cost of memory usage were blocked with request for data showing that the optimization made significant improvement for real world scenarios. We have those scenarios now. There have been several reports of boot time increase in the order of seconds in this thread [1]. Several OEMs and SoC manufacturers have also privately reported significant (350-400ms) increase in boot time due to all the parsing done by fw_devlink. So this patch uses all the setup done by the previous patches in this series to refactor fw_devlink to be more efficient. Most of the code has been moved out of firmware specific (DT mostly) code into driver core. This brings the following benefits: - Instead of parsing the device tree multiple times during bootup, fw_devlink parses each fwnode node/property only once and creates fwnode links. The rest of the fw_devlink code then just looks at these fwnode links to do rest of the work. - Makes it much easier to debug probe issue due to fw_devlink in the future. fw_devlink=on blocks the probing of devices if they depend on a device that hasn't been added yet. With this refactor, it'll be very easy to tell what that device is because we now have a reference to the fwnode of the device. - Much easier to add fw_devlink support to ACPI and other firmware types. A refactor to move the common bits from DT specific code to driver core was in my TODO list as a prerequisite to adding ACPI support to fw_devlink. This series gets that done. [1] - https://lore.kernel.org/linux-omap/ea02f57e-871d-cd16-4418-c1da4bbc4696@ti.com/ Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Tested-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-17-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
The current implementation of fw_devlink is very inefficient because it
tries to get away without creating fwnode links in the name of saving
memory usage. Past attempts to optimize runtime at the cost of memory
usage were blocked with request for data showing that the optimization
made significant improvement for real world scenarios.

We have those scenarios now. There have been several reports of boot
time increase in the order of seconds in this thread [1]. Several OEMs
and SoC manufacturers have also privately reported significant
(350-400ms) increase in boot time due to all the parsing done by
fw_devlink.

So this patch uses all the setup done by the previous patches in this
series to refactor fw_devlink to be more efficient. Most of the code has
been moved out of firmware specific (DT mostly) code into driver core.

This brings the following benefits:
- Instead of parsing the device tree multiple times during bootup,
  fw_devlink parses each fwnode node/property only once and creates
  fwnode links. The rest of the fw_devlink code then just looks at these
  fwnode links to do rest of the work.

- Makes it much easier to debug probe issue due to fw_devlink in the
  future. fw_devlink=on blocks the probing of devices if they depend on
  a device that hasn't been added yet. With this refactor, it'll be very
  easy to tell what that device is because we now have a reference to
  the fwnode of the device.

- Much easier to add fw_devlink support to ACPI and other firmware
  types. A refactor to move the common bits from DT specific code to
  driver core was in my TODO list as a prerequisite to adding ACPI
  support to fw_devlink. This series gets that done.

[1] - https://lore.kernel.org/linux-omap/ea02f57e-871d-cd16-4418-c1da4bbc4696@ti.com/

Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20201121020232.908850-17-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
driver core: Use device's fwnode to check if it is waiting for suppliers 2020-12-09T18:13:02+00:00 Saravana Kannan saravanak@google.com 2020-11-21T02:02:28+00:00 25ac86c6dbe62fba9b97e997fa648cdbe2d40173 To check if a device is still waiting for its supplier devices to be added, we used to check if the devices is in a global waiting_for_suppliers list. Since the global list will be deleted in subsequent patches, this patch stops using this check. Instead, this patch uses a more device specific check. It checks if the device's fwnode has any fwnode links that haven't been converted to device links yet. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-14-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
To check if a device is still waiting for its supplier devices to be
added, we used to check if the devices is in a global
waiting_for_suppliers list. Since the global list will be deleted in
subsequent patches, this patch stops using this check.

Instead, this patch uses a more device specific check. It checks if the
device's fwnode has any fwnode links that haven't been converted to
device links yet.

Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20201121020232.908850-14-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
driver core: Add fw_devlink_parse_fwtree() 2020-12-09T18:10:21+00:00 Saravana Kannan saravanak@google.com 2020-11-21T02:02:27+00:00 c2c724c868c42c5166bf7aa644dd0a0c8d30b47a This function is a wrapper around fwnode_operations.add_links(). This function parses each node in a fwnode tree and create fwnode links for each of those nodes. The information for creating the fwnode links (the supplier and consumer fwnode) is obtained by parsing the properties in each of the fwnodes. This function also ensures that no fwnode is parsed more than once by marking the fwnodes as parsed. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-13-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
This function is a wrapper around fwnode_operations.add_links().

This function parses each node in a fwnode tree and create fwnode links
for each of those nodes. The information for creating the fwnode links
(the supplier and consumer fwnode) is obtained by parsing the properties
in each of the fwnodes.

This function also ensures that no fwnode is parsed more than once by
marking the fwnodes as parsed.

Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20201121020232.908850-13-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
driver core: Allow only unprobed consumers for SYNC_STATE_ONLY device links 2020-12-09T18:10:21+00:00 Saravana Kannan saravanak@google.com 2020-11-21T02:02:24+00:00 ac66c5bbb4371073dcace77e47c234d2e36a006b SYNC_STATE_ONLY device links only affect the behavior of sync_state() callbacks. Specifically, they prevent sync_state() only callbacks from being called on a device if one or more of its consumers haven't probed. So, creating a SYNC_STATE_ONLY device link from an already probed consumer is useless. So, don't allow creating such device links. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-10-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
SYNC_STATE_ONLY device links only affect the behavior of sync_state()
callbacks. Specifically, they prevent sync_state() only callbacks from
being called on a device if one or more of its consumers haven't probed.

So, creating a SYNC_STATE_ONLY device link from an already probed
consumer is useless. So, don't allow creating such device links.

Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20201121020232.908850-10-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
driver core: Add fwnode link support 2020-12-09T18:10:21+00:00 Saravana Kannan saravanak@google.com 2020-11-21T02:02:23+00:00 7b337cb3ebde384cba7405b61dfb84200bf623bf Add support for creating supplier-consumer links between fwnodes. It is intended for internal use the driver core and generic firmware support code (eg. Device Tree, ACPI), so it is simple by design and the API provided is limited. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-9-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Add support for creating supplier-consumer links between fwnodes.  It is
intended for internal use the driver core and generic firmware support
code (eg. Device Tree, ACPI), so it is simple by design and the API
provided is limited.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20201121020232.908850-9-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revert "driver core: fw_devlink: Add support for batching fwnode parsing" 2020-12-09T18:10:20+00:00 Saravana Kannan saravanak@google.com 2020-11-21T02:02:21+00:00 c84b90909e475a2eb4934b4d92fdd10e73e75805 This reverts commit 716a7a25969003d82ab738179c3f1068a120ed11. The fw_devlink_pause/resume() APIs added by the commit being reverted were a first cut attempt at optimizing boot time. But these APIs don't fully solve the problem and are very fragile (can only be used for the top level devices being added). This series replaces them with a much better optimization that works for all device additions and also has the benefit of reducing the complexity of the firmware (DT, EFI) specific code and abstracting out common code to driver core. Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-7-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
This reverts commit 716a7a25969003d82ab738179c3f1068a120ed11.

The fw_devlink_pause/resume() APIs added by the commit being reverted
were a first cut attempt at optimizing boot time. But these APIs don't
fully solve the problem and are very fragile (can only be used for the
top level devices being added). This series replaces them with a much
better optimization that works for all device additions and also has the
benefit of reducing the complexity of the firmware (DT, EFI) specific
code and abstracting out common code to driver core.

Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20201121020232.908850-7-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>