<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/drivers/firmware/efi/Makefile, branch v4.14</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>License cleanup: add SPDX GPL-2.0 license identifier to files with no license</title>
<updated>2017-11-02T10:10:55+00:00</updated>
<author>
<name>Greg Kroah-Hartman</name>
<email>gregkh@linuxfoundation.org</email>
</author>
<published>2017-11-01T14:07:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b24413180f5600bcb3bb70fbed5cf186b60864bd'/>
<id>b24413180f5600bcb3bb70fbed5cf186b60864bd</id>
<content type='text'>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode &amp; Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained &gt;5
   lines of source
 - File already had some variant of a license header in it (even if &lt;5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart &lt;kstewart@linuxfoundation.org&gt;
Reviewed-by: Philippe Ombredanne &lt;pombredanne@nexb.com&gt;
Reviewed-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode &amp; Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained &gt;5
   lines of source
 - File already had some variant of a license header in it (even if &lt;5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart &lt;kstewart@linuxfoundation.org&gt;
Reviewed-by: Philippe Ombredanne &lt;pombredanne@nexb.com&gt;
Reviewed-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/efi/bgrt: Move efi-bgrt handling out of arch/x86</title>
<updated>2017-04-05T10:27:24+00:00</updated>
<author>
<name>Bhupesh Sharma</name>
<email>bhsharma@redhat.com</email>
</author>
<published>2017-04-04T16:02:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=75def552bb1e0d39918df31b86f7d09e754ea0fc'/>
<id>75def552bb1e0d39918df31b86f7d09e754ea0fc</id>
<content type='text'>
Now with open-source boot firmware (EDK2) supporting ACPI BGRT table
addition even for architectures like AARCH64, it makes sense to move
out the 'efi-bgrt.c' file and supporting infrastructure from 'arch/x86'
directory and house it inside 'drivers/firmware/efi', so that this common
code can be used across architectures.

Signed-off-by: Bhupesh Sharma &lt;bhsharma@redhat.com&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170404160245.27812-7-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Now with open-source boot firmware (EDK2) supporting ACPI BGRT table
addition even for architectures like AARCH64, it makes sense to move
out the 'efi-bgrt.c' file and supporting infrastructure from 'arch/x86'
directory and house it inside 'drivers/firmware/efi', so that this common
code can be used across architectures.

Signed-off-by: Bhupesh Sharma &lt;bhsharma@redhat.com&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170404160245.27812-7-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/efi: Retrieve and assign Apple device properties</title>
<updated>2016-11-13T07:23:16+00:00</updated>
<author>
<name>Lukas Wunner</name>
<email>lukas@wunner.de</email>
</author>
<published>2016-11-12T21:32:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=58c5475aba67706b31d9237808d5d3d54074e5ea'/>
<id>58c5475aba67706b31d9237808d5d3d54074e5ea</id>
<content type='text'>
Apple's EFI drivers supply device properties which are needed to support
Macs optimally. They contain vital information which cannot be obtained
any other way (e.g. Thunderbolt Device ROM). They're also used to convey
the current device state so that OS drivers can pick up where EFI
drivers left (e.g. GPU mode setting).

There's an EFI driver dubbed "AAPL,PathProperties" which implements a
per-device key/value store. Other EFI drivers populate it using a custom
protocol. The macOS bootloader /System/Library/CoreServices/boot.efi
retrieves the properties with the same protocol. The kernel extension
AppleACPIPlatform.kext subsequently merges them into the I/O Kit
registry (see ioreg(8)) where they can be queried by other kernel
extensions and user space.

This commit extends the efistub to retrieve the device properties before
ExitBootServices is called. It assigns them to devices in an fs_initcall
so that they can be queried with the API in &lt;linux/property.h&gt;.

Note that the device properties will only be available if the kernel is
booted with the efistub. Distros should adjust their installers to
always use the efistub on Macs. grub with the "linux" directive will not
work unless the functionality of this commit is duplicated in grub.
(The "linuxefi" directive should work but is not included upstream as of
this writing.)

The custom protocol has GUID 91BD12FE-F6C3-44FB-A5B7-5122AB303AE0 and
looks like this:

typedef struct {
	unsigned long version; /* 0x10000 */
	efi_status_t (*get) (
		IN	struct apple_properties_protocol *this,
		IN	struct efi_dev_path *device,
		IN	efi_char16_t *property_name,
		OUT	void *buffer,
		IN OUT	u32 *buffer_len);
		/* EFI_SUCCESS, EFI_NOT_FOUND, EFI_BUFFER_TOO_SMALL */
	efi_status_t (*set) (
		IN	struct apple_properties_protocol *this,
		IN	struct efi_dev_path *device,
		IN	efi_char16_t *property_name,
		IN	void *property_value,
		IN	u32 property_value_len);
		/* allocates copies of property name and value */
		/* EFI_SUCCESS, EFI_OUT_OF_RESOURCES */
	efi_status_t (*del) (
		IN	struct apple_properties_protocol *this,
		IN	struct efi_dev_path *device,
		IN	efi_char16_t *property_name);
		/* EFI_SUCCESS, EFI_NOT_FOUND */
	efi_status_t (*get_all) (
		IN	struct apple_properties_protocol *this,
		OUT	void *buffer,
		IN OUT	u32 *buffer_len);
		/* EFI_SUCCESS, EFI_BUFFER_TOO_SMALL */
} apple_properties_protocol;

Thanks to Pedro Vilaça for this blog post which was helpful in reverse
engineering Apple's EFI drivers and bootloader:
https://reverse.put.as/2016/06/25/apple-efi-firmware-passwords-and-the-scbo-myth/

If someone at Apple is reading this, please note there's a memory leak
in your implementation of the del() function as the property struct is
freed but the name and value allocations are not.

Neither the macOS bootloader nor Apple's EFI drivers check the protocol
version, but we do to avoid breakage if it's ever changed. It's been the
same since at least OS X 10.6 (2009).

The get_all() function conveniently fills a buffer with all properties
in marshalled form which can be passed to the kernel as a setup_data
payload. The number of device properties is dynamic and can change
between a first invocation of get_all() (to determine the buffer size)
and a second invocation (to retrieve the actual buffer), hence the
peculiar loop which does not finish until the buffer size settles.
The macOS bootloader does the same.

The setup_data payload is later on unmarshalled in an fs_initcall. The
idea is that most buses instantiate devices in "subsys" initcall level
and drivers are usually bound to these devices in "device" initcall
level, so we assign the properties in-between, i.e. in "fs" initcall
level.

This assumes that devices to which properties pertain are instantiated
from a "subsys" initcall or earlier. That should always be the case
since on macOS, AppleACPIPlatformExpert::matchEFIDevicePath() only
supports ACPI and PCI nodes and we've fully scanned those buses during
"subsys" initcall level.

The second assumption is that properties are only needed from a "device"
initcall or later. Seems reasonable to me, but should this ever not work
out, an alternative approach would be to store the property sets e.g. in
a btree early during boot. Then whenever device_add() is called, an EFI
Device Path would have to be constructed for the newly added device,
and looked up in the btree. That way, the property set could be assigned
to the device immediately on instantiation. And this would also work for
devices instantiated in a deferred fashion. It seems like this approach
would be more complicated and require more code. That doesn't seem
justified without a specific use case.

For comparison, the strategy on macOS is to assign properties to objects
in the ACPI namespace (AppleACPIPlatformExpert::mergeEFIProperties()).
That approach is definitely wrong as it fails for devices not present in
the namespace: The NHI EFI driver supplies properties for attached
Thunderbolt devices, yet on Macs with Thunderbolt 1 only one device
level behind the host controller is described in the namespace.
Consequently macOS cannot assign properties for chained devices. With
Thunderbolt 2 they started to describe three device levels behind host
controllers in the namespace but this grossly inflates the SSDT and
still fails if the user daisy-chained more than three devices.

We copy the property names and values from the setup_data payload to
swappable virtual memory and afterwards make the payload available to
the page allocator. This is just for the sake of good housekeeping, it
wouldn't occupy a meaningful amount of physical memory (4444 bytes on my
machine). Only the payload is freed, not the setup_data header since
otherwise we'd break the list linkage and we cannot safely update the
predecessor's -&gt;next link because there's no locking for the list.

The payload is currently not passed on to kexec'ed kernels, same for PCI
ROMs retrieved by setup_efi_pci(). This can be added later if there is
demand by amending setup_efi_state(). The payload can then no longer be
made available to the page allocator of course.

Tested-by: Lukas Wunner &lt;lukas@wunner.de&gt; [MacBookPro9,1]
Tested-by: Pierre Moreau &lt;pierre.morrow@free.fr&gt; [MacBookPro11,3]
Signed-off-by: Lukas Wunner &lt;lukas@wunner.de&gt;
Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Andreas Noever &lt;andreas.noever@gmail.com&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Pedro Vilaça &lt;reverser@put.as&gt;
Cc: Peter Jones &lt;pjones@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: grub-devel@gnu.org
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20161112213237.8804-9-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Apple's EFI drivers supply device properties which are needed to support
Macs optimally. They contain vital information which cannot be obtained
any other way (e.g. Thunderbolt Device ROM). They're also used to convey
the current device state so that OS drivers can pick up where EFI
drivers left (e.g. GPU mode setting).

There's an EFI driver dubbed "AAPL,PathProperties" which implements a
per-device key/value store. Other EFI drivers populate it using a custom
protocol. The macOS bootloader /System/Library/CoreServices/boot.efi
retrieves the properties with the same protocol. The kernel extension
AppleACPIPlatform.kext subsequently merges them into the I/O Kit
registry (see ioreg(8)) where they can be queried by other kernel
extensions and user space.

This commit extends the efistub to retrieve the device properties before
ExitBootServices is called. It assigns them to devices in an fs_initcall
so that they can be queried with the API in &lt;linux/property.h&gt;.

Note that the device properties will only be available if the kernel is
booted with the efistub. Distros should adjust their installers to
always use the efistub on Macs. grub with the "linux" directive will not
work unless the functionality of this commit is duplicated in grub.
(The "linuxefi" directive should work but is not included upstream as of
this writing.)

The custom protocol has GUID 91BD12FE-F6C3-44FB-A5B7-5122AB303AE0 and
looks like this:

typedef struct {
	unsigned long version; /* 0x10000 */
	efi_status_t (*get) (
		IN	struct apple_properties_protocol *this,
		IN	struct efi_dev_path *device,
		IN	efi_char16_t *property_name,
		OUT	void *buffer,
		IN OUT	u32 *buffer_len);
		/* EFI_SUCCESS, EFI_NOT_FOUND, EFI_BUFFER_TOO_SMALL */
	efi_status_t (*set) (
		IN	struct apple_properties_protocol *this,
		IN	struct efi_dev_path *device,
		IN	efi_char16_t *property_name,
		IN	void *property_value,
		IN	u32 property_value_len);
		/* allocates copies of property name and value */
		/* EFI_SUCCESS, EFI_OUT_OF_RESOURCES */
	efi_status_t (*del) (
		IN	struct apple_properties_protocol *this,
		IN	struct efi_dev_path *device,
		IN	efi_char16_t *property_name);
		/* EFI_SUCCESS, EFI_NOT_FOUND */
	efi_status_t (*get_all) (
		IN	struct apple_properties_protocol *this,
		OUT	void *buffer,
		IN OUT	u32 *buffer_len);
		/* EFI_SUCCESS, EFI_BUFFER_TOO_SMALL */
} apple_properties_protocol;

Thanks to Pedro Vilaça for this blog post which was helpful in reverse
engineering Apple's EFI drivers and bootloader:
https://reverse.put.as/2016/06/25/apple-efi-firmware-passwords-and-the-scbo-myth/

If someone at Apple is reading this, please note there's a memory leak
in your implementation of the del() function as the property struct is
freed but the name and value allocations are not.

Neither the macOS bootloader nor Apple's EFI drivers check the protocol
version, but we do to avoid breakage if it's ever changed. It's been the
same since at least OS X 10.6 (2009).

The get_all() function conveniently fills a buffer with all properties
in marshalled form which can be passed to the kernel as a setup_data
payload. The number of device properties is dynamic and can change
between a first invocation of get_all() (to determine the buffer size)
and a second invocation (to retrieve the actual buffer), hence the
peculiar loop which does not finish until the buffer size settles.
The macOS bootloader does the same.

The setup_data payload is later on unmarshalled in an fs_initcall. The
idea is that most buses instantiate devices in "subsys" initcall level
and drivers are usually bound to these devices in "device" initcall
level, so we assign the properties in-between, i.e. in "fs" initcall
level.

This assumes that devices to which properties pertain are instantiated
from a "subsys" initcall or earlier. That should always be the case
since on macOS, AppleACPIPlatformExpert::matchEFIDevicePath() only
supports ACPI and PCI nodes and we've fully scanned those buses during
"subsys" initcall level.

The second assumption is that properties are only needed from a "device"
initcall or later. Seems reasonable to me, but should this ever not work
out, an alternative approach would be to store the property sets e.g. in
a btree early during boot. Then whenever device_add() is called, an EFI
Device Path would have to be constructed for the newly added device,
and looked up in the btree. That way, the property set could be assigned
to the device immediately on instantiation. And this would also work for
devices instantiated in a deferred fashion. It seems like this approach
would be more complicated and require more code. That doesn't seem
justified without a specific use case.

For comparison, the strategy on macOS is to assign properties to objects
in the ACPI namespace (AppleACPIPlatformExpert::mergeEFIProperties()).
That approach is definitely wrong as it fails for devices not present in
the namespace: The NHI EFI driver supplies properties for attached
Thunderbolt devices, yet on Macs with Thunderbolt 1 only one device
level behind the host controller is described in the namespace.
Consequently macOS cannot assign properties for chained devices. With
Thunderbolt 2 they started to describe three device levels behind host
controllers in the namespace but this grossly inflates the SSDT and
still fails if the user daisy-chained more than three devices.

We copy the property names and values from the setup_data payload to
swappable virtual memory and afterwards make the payload available to
the page allocator. This is just for the sake of good housekeeping, it
wouldn't occupy a meaningful amount of physical memory (4444 bytes on my
machine). Only the payload is freed, not the setup_data header since
otherwise we'd break the list linkage and we cannot safely update the
predecessor's -&gt;next link because there's no locking for the list.

The payload is currently not passed on to kexec'ed kernels, same for PCI
ROMs retrieved by setup_efi_pci(). This can be added later if there is
demand by amending setup_efi_state(). The payload can then no longer be
made available to the page allocator of course.

Tested-by: Lukas Wunner &lt;lukas@wunner.de&gt; [MacBookPro9,1]
Tested-by: Pierre Moreau &lt;pierre.morrow@free.fr&gt; [MacBookPro11,3]
Signed-off-by: Lukas Wunner &lt;lukas@wunner.de&gt;
Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Andreas Noever &lt;andreas.noever@gmail.com&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Pedro Vilaça &lt;reverser@put.as&gt;
Cc: Peter Jones &lt;pjones@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: grub-devel@gnu.org
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20161112213237.8804-9-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi: Add device path parser</title>
<updated>2016-11-13T07:23:15+00:00</updated>
<author>
<name>Lukas Wunner</name>
<email>lukas@wunner.de</email>
</author>
<published>2016-11-12T21:32:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=46cd4b75cd0edee76e0096225c2d31f8d90e92a2'/>
<id>46cd4b75cd0edee76e0096225c2d31f8d90e92a2</id>
<content type='text'>
We're about to extended the efistub to retrieve device properties from
EFI on Apple Macs. The properties use EFI Device Paths to indicate the
device they belong to. This commit adds a parser which, given an EFI
Device Path, locates the corresponding struct device and returns a
reference to it.

Initially only ACPI and PCI Device Path nodes are supported, these are
the only types needed for Apple device properties (the corresponding
macOS function AppleACPIPlatformExpert::matchEFIDevicePath() does not
support any others). Further node types can be added with little to
moderate effort.

Apple device properties is currently the only use case of this parser,
but Peter Jones intends to use it to match up devices with the
ConInDev/ConOutDev/ErrOutDev variables and add sysfs attributes to these
devices to say the hardware supports using them as console. Thus,
make this parser a separate component which can be selected with config
option EFI_DEV_PATH_PARSER. It can in principle be compiled as a module
if acpi_get_first_physical_node() and acpi_bus_type are exported (and
efi_get_device_by_path() itself is exported).

The dependency on CONFIG_ACPI is needed for acpi_match_device_ids().
It can be removed if an empty inline stub is added for that function.

Signed-off-by: Lukas Wunner &lt;lukas@wunner.de&gt;
Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Andreas Noever &lt;andreas.noever@gmail.com&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Jones &lt;pjones@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20161112213237.8804-7-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We're about to extended the efistub to retrieve device properties from
EFI on Apple Macs. The properties use EFI Device Paths to indicate the
device they belong to. This commit adds a parser which, given an EFI
Device Path, locates the corresponding struct device and returns a
reference to it.

Initially only ACPI and PCI Device Path nodes are supported, these are
the only types needed for Apple device properties (the corresponding
macOS function AppleACPIPlatformExpert::matchEFIDevicePath() does not
support any others). Further node types can be added with little to
moderate effort.

Apple device properties is currently the only use case of this parser,
but Peter Jones intends to use it to match up devices with the
ConInDev/ConOutDev/ErrOutDev variables and add sysfs attributes to these
devices to say the hardware supports using them as console. Thus,
make this parser a separate component which can be selected with config
option EFI_DEV_PATH_PARSER. It can in principle be compiled as a module
if acpi_get_first_physical_node() and acpi_bus_type are exported (and
efi_get_device_by_path() itself is exported).

The dependency on CONFIG_ACPI is needed for acpi_match_device_ids().
It can be removed if an empty inline stub is added for that function.

Signed-off-by: Lukas Wunner &lt;lukas@wunner.de&gt;
Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Andreas Noever &lt;andreas.noever@gmail.com&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Jones &lt;pjones@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20161112213237.8804-7-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi: Add efi_test driver for exporting UEFI runtime service interfaces</title>
<updated>2016-09-09T15:08:53+00:00</updated>
<author>
<name>Ivan Hu</name>
<email>ivan.hu@canonical.com</email>
</author>
<published>2016-08-25T03:15:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ff6301dabc3ca20ab8f50f8d0252ac05da610d89'/>
<id>ff6301dabc3ca20ab8f50f8d0252ac05da610d89</id>
<content type='text'>
This driver is used by the Firmware Test Suite (FWTS) for testing the UEFI
runtime interfaces readiness of the firmware.

This driver exports UEFI runtime service interfaces into userspace,
which allows to use and test UEFI runtime services provided by the
firmware.

This driver uses the efi.&lt;service&gt; function pointers directly instead of
going through the efivar API to allow for direct testing of the UEFI
runtime service interfaces provided by the firmware.

Details for FWTS are available from,
&lt;https://wiki.ubuntu.com/FirmwareTestSuite&gt;

Signed-off-by: Ivan Hu &lt;ivan.hu@canonical.com&gt;
Cc: joeyli &lt;jlee@suse.com&gt;
Cc: Ricardo Neri &lt;ricardo.neri-calderon@linux.intel.com&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This driver is used by the Firmware Test Suite (FWTS) for testing the UEFI
runtime interfaces readiness of the firmware.

This driver exports UEFI runtime service interfaces into userspace,
which allows to use and test UEFI runtime services provided by the
firmware.

This driver uses the efi.&lt;service&gt; function pointers directly instead of
going through the efivar API to allow for direct testing of the UEFI
runtime service interfaces provided by the firmware.

Details for FWTS are available from,
&lt;https://wiki.ubuntu.com/FirmwareTestSuite&gt;

Signed-off-by: Ivan Hu &lt;ivan.hu@canonical.com&gt;
Cc: joeyli &lt;jlee@suse.com&gt;
Cc: Ricardo Neri &lt;ricardo.neri-calderon@linux.intel.com&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi: Split out EFI memory map functions into new file</title>
<updated>2016-09-09T15:07:46+00:00</updated>
<author>
<name>Matt Fleming</name>
<email>matt@codeblueprint.co.uk</email>
</author>
<published>2016-02-29T20:30:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=60863c0d1a96b740048cc7d94a2d00d6f89ba3d8'/>
<id>60863c0d1a96b740048cc7d94a2d00d6f89ba3d8</id>
<content type='text'>
Also move the functions from the EFI fake mem driver since future
patches will require access to the memmap insertion code even if
CONFIG_EFI_FAKE_MEM isn't enabled.

This will be useful when we need to build custom EFI memory maps to
allow drivers to mark regions as reserved.

Tested-by: Dave Young &lt;dyoung@redhat.com&gt; [kexec/kdump]
Tested-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt; [arm]
Acked-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Leif Lindholm &lt;leif.lindholm@linaro.org&gt;
Cc: Peter Jones &lt;pjones@redhat.com&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Taku Izumi &lt;izumi.taku@jp.fujitsu.com&gt;
Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Also move the functions from the EFI fake mem driver since future
patches will require access to the memmap insertion code even if
CONFIG_EFI_FAKE_MEM isn't enabled.

This will be useful when we need to build custom EFI memory maps to
allow drivers to mark regions as reserved.

Tested-by: Dave Young &lt;dyoung@redhat.com&gt; [kexec/kdump]
Tested-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt; [arm]
Acked-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Leif Lindholm &lt;leif.lindholm@linaro.org&gt;
Cc: Peter Jones &lt;pjones@redhat.com&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Taku Izumi &lt;izumi.taku@jp.fujitsu.com&gt;
Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi: Add misc char driver interface to update EFI firmware</title>
<updated>2016-04-28T09:34:05+00:00</updated>
<author>
<name>Kweh, Hock Leong</name>
<email>hock.leong.kweh@intel.com</email>
</author>
<published>2016-04-25T20:07:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=65117f1aa1b2d145fd5ca376bde642794d0aae1b'/>
<id>65117f1aa1b2d145fd5ca376bde642794d0aae1b</id>
<content type='text'>
This patch introduces a kernel module to expose a capsule loader
interface (misc char device file note) for users to upload capsule
binaries.

Example:

  cat firmware.bin &gt; /dev/efi_capsule_loader

Any upload error will be returned while doing "cat" through file
operation write() function call.

Signed-off-by: Kweh, Hock Leong &lt;hock.leong.kweh@intel.com&gt;
[ Update comments and Kconfig text ]
Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Reviewed-by: Bryan O'Donoghue &lt;pure.logic@nexus-software.ie&gt;
Acked-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Andy Lutomirski &lt;luto@amacapital.net&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Peter Jones &lt;pjones@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Sam Protsenko &lt;semen.protsenko@linaro.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: joeyli &lt;jlee@suse.com&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-30-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This patch introduces a kernel module to expose a capsule loader
interface (misc char device file note) for users to upload capsule
binaries.

Example:

  cat firmware.bin &gt; /dev/efi_capsule_loader

Any upload error will be returned while doing "cat" through file
operation write() function call.

Signed-off-by: Kweh, Hock Leong &lt;hock.leong.kweh@intel.com&gt;
[ Update comments and Kconfig text ]
Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Reviewed-by: Bryan O'Donoghue &lt;pure.logic@nexus-software.ie&gt;
Acked-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Andy Lutomirski &lt;luto@amacapital.net&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Peter Jones &lt;pjones@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Sam Protsenko &lt;semen.protsenko@linaro.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: joeyli &lt;jlee@suse.com&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-30-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi: Add 'capsule' update support</title>
<updated>2016-04-28T09:34:03+00:00</updated>
<author>
<name>Matt Fleming</name>
<email>matt@codeblueprint.co.uk</email>
</author>
<published>2016-04-25T20:06:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f0133f3c5b8bb34ec4dec50c27e7a655aeee8935'/>
<id>f0133f3c5b8bb34ec4dec50c27e7a655aeee8935</id>
<content type='text'>
The EFI capsule mechanism allows data blobs to be passed to the EFI
firmware. A common use case is performing firmware updates. This patch
just introduces the main infrastructure for interacting with the
firmware, and a driver that allows users to upload capsules will come
in a later patch.

Once a capsule has been passed to the firmware, the next reboot must
be performed using the ResetSystem() EFI runtime service, which may
involve overriding the reboot type specified by reboot=. This ensures
the reset value returned by QueryCapsuleCapabilities() is used to
reset the system, which is required for the capsule to be processed.
efi_capsule_pending() is provided for this purpose.

At the moment we only allow a single capsule blob to be sent to the
firmware despite the fact that UpdateCapsule() takes a 'CapsuleCount'
parameter. This simplifies the API and shouldn't result in any
downside since it is still possible to send multiple capsules by
repeatedly calling UpdateCapsule().

Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Bryan O'Donoghue &lt;pure.logic@nexus-software.ie&gt;
Cc: Kweh Hock Leong &lt;hock.leong.kweh@intel.com&gt;
Cc: Mark Salter &lt;msalter@redhat.com&gt;
Cc: Peter Jones &lt;pjones@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: joeyli &lt;jlee@suse.com&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-28-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The EFI capsule mechanism allows data blobs to be passed to the EFI
firmware. A common use case is performing firmware updates. This patch
just introduces the main infrastructure for interacting with the
firmware, and a driver that allows users to upload capsules will come
in a later patch.

Once a capsule has been passed to the firmware, the next reboot must
be performed using the ResetSystem() EFI runtime service, which may
involve overriding the reboot type specified by reboot=. This ensures
the reset value returned by QueryCapsuleCapabilities() is used to
reset the system, which is required for the capsule to be processed.
efi_capsule_pending() is provided for this purpose.

At the moment we only allow a single capsule blob to be sent to the
firmware despite the fact that UpdateCapsule() takes a 'CapsuleCount'
parameter. This simplifies the API and shouldn't result in any
downside since it is still possible to send multiple capsules by
repeatedly calling UpdateCapsule().

Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Bryan O'Donoghue &lt;pure.logic@nexus-software.ie&gt;
Cc: Kweh Hock Leong &lt;hock.leong.kweh@intel.com&gt;
Cc: Mark Salter &lt;msalter@redhat.com&gt;
Cc: Peter Jones &lt;pjones@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: joeyli &lt;jlee@suse.com&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-28-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efibc: Add EFI Bootloader Control module</title>
<updated>2016-04-28T09:34:02+00:00</updated>
<author>
<name>Compostella, Jeremy</name>
<email>jeremy.compostella@intel.com</email>
</author>
<published>2016-04-25T20:06:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=06f7d4a1618dbb086e738c93cd1ef416ab01027d'/>
<id>06f7d4a1618dbb086e738c93cd1ef416ab01027d</id>
<content type='text'>
This module installs a reboot callback, such that if reboot() is invoked
with a string argument NNN, "NNN" is copied to the "LoaderEntryOneShot"
EFI variable, to be read by the bootloader.

If the string matches one of the boot labels defined in its configuration,
the bootloader will boot once to that label.  The "LoaderEntryRebootReason"
EFI variable is set with the reboot reason: "reboot", "shutdown".

The bootloader reads this reboot reason and takes particular action
according to its policy.

There are reboot implementations that do "reboot &lt;reason&gt;", such as
Android's reboot command and Upstart's reboot replacement, which pass
the reason as an argument to the reboot syscall.  There is no
platform-agnostic way how those could be modified to pass the reason
to the bootloader, regardless of platform or bootloader.

Signed-off-by: Jeremy Compostella &lt;jeremy.compostella@intel.com&gt;
Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Stefan Stanacar &lt;stefan.stanacar@intel.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-26-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This module installs a reboot callback, such that if reboot() is invoked
with a string argument NNN, "NNN" is copied to the "LoaderEntryOneShot"
EFI variable, to be read by the bootloader.

If the string matches one of the boot labels defined in its configuration,
the bootloader will boot once to that label.  The "LoaderEntryRebootReason"
EFI variable is set with the reboot reason: "reboot", "shutdown".

The bootloader reads this reboot reason and takes particular action
according to its policy.

There are reboot implementations that do "reboot &lt;reason&gt;", such as
Android's reboot command and Upstart's reboot replacement, which pass
the reason as an argument to the reboot syscall.  There is no
platform-agnostic way how those could be modified to pass the reason
to the bootloader, regardless of platform or bootloader.

Signed-off-by: Jeremy Compostella &lt;jeremy.compostella@intel.com&gt;
Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Stefan Stanacar &lt;stefan.stanacar@intel.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-26-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi: Implement generic support for the Memory Attributes table</title>
<updated>2016-04-28T09:33:54+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ard.biesheuvel@linaro.org</email>
</author>
<published>2016-04-25T20:06:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=10f0d2f57705350bbbe5f28e9292ae3905823c3c'/>
<id>10f0d2f57705350bbbe5f28e9292ae3905823c3c</id>
<content type='text'>
This implements shared support for discovering the presence of the
Memory Attributes table, and for parsing and validating its contents.

The table is validated against the construction rules in the UEFI spec.
Since this is a new table, it makes sense to complain if we encounter
a table that does not follow those rules.

The parsing and validation routine takes a callback that can be specified
per architecture, that gets passed each unique validated region, with the
virtual address retrieved from the ordinary memory map.

Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
[ Trim pr_*() strings to 80 cols and use EFI consistently. ]
Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Leif Lindholm &lt;leif.lindholm@linaro.org&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Peter Jones &lt;pjones@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Sai Praneeth Prakhya &lt;sai.praneeth.prakhya@intel.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-14-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This implements shared support for discovering the presence of the
Memory Attributes table, and for parsing and validating its contents.

The table is validated against the construction rules in the UEFI spec.
Since this is a new table, it makes sense to complain if we encounter
a table that does not follow those rules.

The parsing and validation routine takes a callback that can be specified
per architecture, that gets passed each unique validated region, with the
virtual address retrieved from the ordinary memory map.

Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
[ Trim pr_*() strings to 80 cols and use EFI consistently. ]
Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Leif Lindholm &lt;leif.lindholm@linaro.org&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Peter Jones &lt;pjones@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Sai Praneeth Prakhya &lt;sai.praneeth.prakhya@intel.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-14-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
