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* [PATCH] of: document /sys/firmware/fdt
@ 2017-06-14  4:20 frowand.list
  2017-06-14  9:55 ` Mark Rutland
                   ` (2 more replies)
  0 siblings, 3 replies; 9+ messages in thread
From: frowand.list @ 2017-06-14  4:20 UTC (permalink / raw)
  To: Rob Herring; +Cc: devicetree, linux-kernel

From: Frank Rowand <frank.rowand@sony.com>

Add ABI documentation for /sys/firmware/fdt

Update contact for /sys/firmware/devicetree/* to include mail list

Signed-off-by: Frank Rowand <frank.rowand@sony.com>
---
 Documentation/ABI/testing/sysfs-firmware-ofw | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/Documentation/ABI/testing/sysfs-firmware-ofw b/Documentation/ABI/testing/sysfs-firmware-ofw
index f562b188e71d..8e700db6c295 100644
--- a/Documentation/ABI/testing/sysfs-firmware-ofw
+++ b/Documentation/ABI/testing/sysfs-firmware-ofw
@@ -1,6 +1,6 @@
 What:		/sys/firmware/devicetree/*
 Date:		November 2013
-Contact:	Grant Likely <grant.likely@linaro.org>
+Contact:	Grant Likely <grant.likely@linaro.org>, devicetree@vger.kernel.org
 Description:
 		When using OpenFirmware or a Flattened Device Tree to enumerate
 		hardware, the device tree structure will be exposed in this
@@ -26,3 +26,28 @@ Description:
 		name plus address). Properties are represented as files
 		in the directory. The contents of each file is the exact
 		binary data from the device tree.
+
+What:		/sys/firmware/fdt
+Date:		February 2015
+KernelVersion:	3.19
+Contact:	Frank Rowand <frank.rowand@sony.com>, devicetree@vger.kernel.org
+Description:
+		Exports the FDT blob that was passed to the kernel by
+		the bootloader. This allows userland applications such
+		as kexec to access the raw binary. This blob is also
+		useful when debugging since it contains any changes
+		made to the blob by the bootloader.
+
+		The fact that this node does not reside under
+		/sys/firmware/device-tree is deliberate: FDT is also used
+		on arm64 UEFI/ACPI systems to communicate just the UEFI
+		and ACPI entry points, but the FDT is never unflattened
+		and used to configure the system.
+
+		A CRC32 checksum is calculated over the entire FDT
+		blob, and verified at late_initcall time. The sysfs
+		entry is instantiated only if the checksum is valid,
+		i.e., if the FDT blob has not been modified in the mean
+		time. Otherwise, a warning is printed.
+Users:		kexec, debugging
+
-- 
Frank Rowand <frank.rowand@sony.com>

^ permalink raw reply related	[flat|nested] 9+ messages in thread

* Re: [PATCH] of: document /sys/firmware/fdt
  2017-06-14  4:20 [PATCH] of: document /sys/firmware/fdt frowand.list
@ 2017-06-14  9:55 ` Mark Rutland
  2017-06-14 10:16   ` Ard Biesheuvel
  2017-06-22 15:21 ` Rob Herring
  2017-06-29 13:28 ` Grant Likely
  2 siblings, 1 reply; 9+ messages in thread
From: Mark Rutland @ 2017-06-14  9:55 UTC (permalink / raw)
  To: frowand.list; +Cc: Rob Herring, devicetree, linux-kernel, Ard Biesheuvel

[Adding Ard, as he added /sys/firmware/fdt]

On Tue, Jun 13, 2017 at 09:20:07PM -0700, frowand.list@gmail.com wrote:
> From: Frank Rowand <frank.rowand@sony.com>
>
> Add ABI documentation for /sys/firmware/fdt
>
> Update contact for /sys/firmware/devicetree/* to include mail list
>
> Signed-off-by: Frank Rowand <frank.rowand@sony.com>

FWIW:

Acked-by: Mark Rutland <mark.rutland@arm.com>

Mark.

> ---
>  Documentation/ABI/testing/sysfs-firmware-ofw | 27 ++++++++++++++++++++++++++-
>  1 file changed, 26 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/ABI/testing/sysfs-firmware-ofw b/Documentation/ABI/testing/sysfs-firmware-ofw
> index f562b188e71d..8e700db6c295 100644
> --- a/Documentation/ABI/testing/sysfs-firmware-ofw
> +++ b/Documentation/ABI/testing/sysfs-firmware-ofw
> @@ -1,6 +1,6 @@
>  What:                /sys/firmware/devicetree/*
>  Date:                November 2013
> -Contact:     Grant Likely <grant.likely@linaro.org>
> +Contact:     Grant Likely <grant.likely@linaro.org>, devicetree@vger.kernel.org
>  Description:
>               When using OpenFirmware or a Flattened Device Tree to enumerate
>               hardware, the device tree structure will be exposed in this
> @@ -26,3 +26,28 @@ Description:
>               name plus address). Properties are represented as files
>               in the directory. The contents of each file is the exact
>               binary data from the device tree.
> +
> +What:                /sys/firmware/fdt
> +Date:                February 2015
> +KernelVersion:       3.19
> +Contact:     Frank Rowand <frank.rowand@sony.com>, devicetree@vger.kernel.org
> +Description:
> +             Exports the FDT blob that was passed to the kernel by
> +             the bootloader. This allows userland applications such
> +             as kexec to access the raw binary. This blob is also
> +             useful when debugging since it contains any changes
> +             made to the blob by the bootloader.
> +
> +             The fact that this node does not reside under
> +             /sys/firmware/device-tree is deliberate: FDT is also used
> +             on arm64 UEFI/ACPI systems to communicate just the UEFI
> +             and ACPI entry points, but the FDT is never unflattened
> +             and used to configure the system.
> +
> +             A CRC32 checksum is calculated over the entire FDT
> +             blob, and verified at late_initcall time. The sysfs
> +             entry is instantiated only if the checksum is valid,
> +             i.e., if the FDT blob has not been modified in the mean
> +             time. Otherwise, a warning is printed.
> +Users:               kexec, debugging
> +
> --
> Frank Rowand <frank.rowand@sony.com>
>
> --
> To unsubscribe from this list: send the line "unsubscribe devicetree" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH] of: document /sys/firmware/fdt
  2017-06-14  9:55 ` Mark Rutland
@ 2017-06-14 10:16   ` Ard Biesheuvel
  0 siblings, 0 replies; 9+ messages in thread
From: Ard Biesheuvel @ 2017-06-14 10:16 UTC (permalink / raw)
  To: Mark Rutland; +Cc: Frank Rowand, Rob Herring, devicetree, linux-kernel

On 14 June 2017 at 11:55, Mark Rutland <mark.rutland@arm.com> wrote:
> [Adding Ard, as he added /sys/firmware/fdt]
>

Thanks

> On Tue, Jun 13, 2017 at 09:20:07PM -0700, frowand.list@gmail.com wrote:
>> From: Frank Rowand <frank.rowand@sony.com>
>>
>> Add ABI documentation for /sys/firmware/fdt
>>
>> Update contact for /sys/firmware/devicetree/* to include mail list
>>
>> Signed-off-by: Frank Rowand <frank.rowand@sony.com>
>
> FWIW:
>
> Acked-by: Mark Rutland <mark.rutland@arm.com>
>

Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

>> ---
>>  Documentation/ABI/testing/sysfs-firmware-ofw | 27 ++++++++++++++++++++++++++-
>>  1 file changed, 26 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/ABI/testing/sysfs-firmware-ofw b/Documentation/ABI/testing/sysfs-firmware-ofw
>> index f562b188e71d..8e700db6c295 100644
>> --- a/Documentation/ABI/testing/sysfs-firmware-ofw
>> +++ b/Documentation/ABI/testing/sysfs-firmware-ofw
>> @@ -1,6 +1,6 @@
>>  What:                /sys/firmware/devicetree/*
>>  Date:                November 2013
>> -Contact:     Grant Likely <grant.likely@linaro.org>
>> +Contact:     Grant Likely <grant.likely@linaro.org>, devicetree@vger.kernel.org
>>  Description:
>>               When using OpenFirmware or a Flattened Device Tree to enumerate
>>               hardware, the device tree structure will be exposed in this
>> @@ -26,3 +26,28 @@ Description:
>>               name plus address). Properties are represented as files
>>               in the directory. The contents of each file is the exact
>>               binary data from the device tree.
>> +
>> +What:                /sys/firmware/fdt
>> +Date:                February 2015
>> +KernelVersion:       3.19
>> +Contact:     Frank Rowand <frank.rowand@sony.com>, devicetree@vger.kernel.org
>> +Description:
>> +             Exports the FDT blob that was passed to the kernel by
>> +             the bootloader. This allows userland applications such
>> +             as kexec to access the raw binary. This blob is also
>> +             useful when debugging since it contains any changes
>> +             made to the blob by the bootloader.
>> +
>> +             The fact that this node does not reside under
>> +             /sys/firmware/device-tree is deliberate: FDT is also used
>> +             on arm64 UEFI/ACPI systems to communicate just the UEFI
>> +             and ACPI entry points, but the FDT is never unflattened
>> +             and used to configure the system.
>> +
>> +             A CRC32 checksum is calculated over the entire FDT
>> +             blob, and verified at late_initcall time. The sysfs
>> +             entry is instantiated only if the checksum is valid,
>> +             i.e., if the FDT blob has not been modified in the mean
>> +             time. Otherwise, a warning is printed.
>> +Users:               kexec, debugging
>> +
>> --
>> Frank Rowand <frank.rowand@sony.com>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe devicetree" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH] of: document /sys/firmware/fdt
  2017-06-14  4:20 [PATCH] of: document /sys/firmware/fdt frowand.list
  2017-06-14  9:55 ` Mark Rutland
@ 2017-06-22 15:21 ` Rob Herring
  2017-06-22 15:23   ` Rob Herring
  2017-06-29 13:28 ` Grant Likely
  2 siblings, 1 reply; 9+ messages in thread
From: Rob Herring @ 2017-06-22 15:21 UTC (permalink / raw)
  To: frowand.list; +Cc: devicetree, linux-kernel

On Tue, Jun 13, 2017 at 09:20:07PM -0700, frowand.list@gmail.com wrote:
> From: Frank Rowand <frank.rowand@sony.com>
> 
> Add ABI documentation for /sys/firmware/fdt
> 
> Update contact for /sys/firmware/devicetree/* to include mail list
> 
> Signed-off-by: Frank Rowand <frank.rowand@sony.com>
> ---
>  Documentation/ABI/testing/sysfs-firmware-ofw | 27 ++++++++++++++++++++++++++-
>  1 file changed, 26 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/ABI/testing/sysfs-firmware-ofw b/Documentation/ABI/testing/sysfs-firmware-ofw
> index f562b188e71d..8e700db6c295 100644
> --- a/Documentation/ABI/testing/sysfs-firmware-ofw
> +++ b/Documentation/ABI/testing/sysfs-firmware-ofw
> @@ -1,6 +1,6 @@
>  What:		/sys/firmware/devicetree/*
>  Date:		November 2013
> -Contact:	Grant Likely <grant.likely@linaro.org>
> +Contact:	Grant Likely <grant.likely@linaro.org>, devicetree@vger.kernel.org

Grant's email is not valid either. I would just drop it unless he wants 
his secretlab.ca email.

Rob

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH] of: document /sys/firmware/fdt
  2017-06-22 15:21 ` Rob Herring
@ 2017-06-22 15:23   ` Rob Herring
  2017-06-28 21:46     ` Frank Rowand
  0 siblings, 1 reply; 9+ messages in thread
From: Rob Herring @ 2017-06-22 15:23 UTC (permalink / raw)
  To: frowand.list, glikely; +Cc: devicetree, linux-kernel

Meant to add Grant.

On Thu, Jun 22, 2017 at 10:21:24AM -0500, Rob Herring wrote:
> On Tue, Jun 13, 2017 at 09:20:07PM -0700, frowand.list@gmail.com wrote:
> > From: Frank Rowand <frank.rowand@sony.com>
> > 
> > Add ABI documentation for /sys/firmware/fdt
> > 
> > Update contact for /sys/firmware/devicetree/* to include mail list
> > 
> > Signed-off-by: Frank Rowand <frank.rowand@sony.com>
> > ---
> >  Documentation/ABI/testing/sysfs-firmware-ofw | 27 ++++++++++++++++++++++++++-
> >  1 file changed, 26 insertions(+), 1 deletion(-)
> > 
> > diff --git a/Documentation/ABI/testing/sysfs-firmware-ofw b/Documentation/ABI/testing/sysfs-firmware-ofw
> > index f562b188e71d..8e700db6c295 100644
> > --- a/Documentation/ABI/testing/sysfs-firmware-ofw
> > +++ b/Documentation/ABI/testing/sysfs-firmware-ofw
> > @@ -1,6 +1,6 @@
> >  What:		/sys/firmware/devicetree/*
> >  Date:		November 2013
> > -Contact:	Grant Likely <grant.likely@linaro.org>
> > +Contact:	Grant Likely <grant.likely@linaro.org>, devicetree@vger.kernel.org
> 
> Grant's email is not valid either. I would just drop it unless he wants 
> his secretlab.ca email.
> 
> Rob

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH] of: document /sys/firmware/fdt
  2017-06-22 15:23   ` Rob Herring
@ 2017-06-28 21:46     ` Frank Rowand
  2017-06-28 21:49       ` Grant Likely
  0 siblings, 1 reply; 9+ messages in thread
From: Frank Rowand @ 2017-06-28 21:46 UTC (permalink / raw)
  To: Rob Herring, glikely; +Cc: devicetree, linux-kernel

On 06/22/17 08:23, Rob Herring wrote:
> Meant to add Grant.
> 
> On Thu, Jun 22, 2017 at 10:21:24AM -0500, Rob Herring wrote:
>> On Tue, Jun 13, 2017 at 09:20:07PM -0700, frowand.list@gmail.com wrote:
>>> From: Frank Rowand <frank.rowand@sony.com>
>>>
>>> Add ABI documentation for /sys/firmware/fdt
>>>
>>> Update contact for /sys/firmware/devicetree/* to include mail list
>>>
>>> Signed-off-by: Frank Rowand <frank.rowand@sony.com>
>>> ---
>>>  Documentation/ABI/testing/sysfs-firmware-ofw | 27 ++++++++++++++++++++++++++-
>>>  1 file changed, 26 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/Documentation/ABI/testing/sysfs-firmware-ofw b/Documentation/ABI/testing/sysfs-firmware-ofw
>>> index f562b188e71d..8e700db6c295 100644
>>> --- a/Documentation/ABI/testing/sysfs-firmware-ofw
>>> +++ b/Documentation/ABI/testing/sysfs-firmware-ofw
>>> @@ -1,6 +1,6 @@
>>>  What:		/sys/firmware/devicetree/*
>>>  Date:		November 2013
>>> -Contact:	Grant Likely <grant.likely@linaro.org>
>>> +Contact:	Grant Likely <grant.likely@linaro.org>, devicetree@vger.kernel.org
>>
>> Grant's email is not valid either. I would just drop it unless he wants 
>> his secretlab.ca email.
>>
>> Rob
> 

No response from Grant, so I'll drop his email and add the mail list.

Also, for the newly added section I'll change the contact from being both
me and the mail list to just be the mail list.

-Frank

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH] of: document /sys/firmware/fdt
  2017-06-28 21:46     ` Frank Rowand
@ 2017-06-28 21:49       ` Grant Likely
  2017-06-28 22:04         ` Frank Rowand
  0 siblings, 1 reply; 9+ messages in thread
From: Grant Likely @ 2017-06-28 21:49 UTC (permalink / raw)
  To: Frank Rowand; +Cc: Rob Herring, devicetree, Linux Kernel Mailing List

I'm slowly getting back into things and plan to actively participate.
Please use my ARM address:

grant.likely@arm.com

g.

On Wed, Jun 28, 2017 at 10:46 PM, Frank Rowand <frowand.list@gmail.com> wrote:
> On 06/22/17 08:23, Rob Herring wrote:
>> Meant to add Grant.
>>
>> On Thu, Jun 22, 2017 at 10:21:24AM -0500, Rob Herring wrote:
>>> On Tue, Jun 13, 2017 at 09:20:07PM -0700, frowand.list@gmail.com wrote:
>>>> From: Frank Rowand <frank.rowand@sony.com>
>>>>
>>>> Add ABI documentation for /sys/firmware/fdt
>>>>
>>>> Update contact for /sys/firmware/devicetree/* to include mail list
>>>>
>>>> Signed-off-by: Frank Rowand <frank.rowand@sony.com>
>>>> ---
>>>>  Documentation/ABI/testing/sysfs-firmware-ofw | 27 ++++++++++++++++++++++++++-
>>>>  1 file changed, 26 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/Documentation/ABI/testing/sysfs-firmware-ofw b/Documentation/ABI/testing/sysfs-firmware-ofw
>>>> index f562b188e71d..8e700db6c295 100644
>>>> --- a/Documentation/ABI/testing/sysfs-firmware-ofw
>>>> +++ b/Documentation/ABI/testing/sysfs-firmware-ofw
>>>> @@ -1,6 +1,6 @@
>>>>  What:              /sys/firmware/devicetree/*
>>>>  Date:              November 2013
>>>> -Contact:   Grant Likely <grant.likely@linaro.org>
>>>> +Contact:   Grant Likely <grant.likely@linaro.org>, devicetree@vger.kernel.org
>>>
>>> Grant's email is not valid either. I would just drop it unless he wants
>>> his secretlab.ca email.
>>>
>>> Rob
>>
>
> No response from Grant, so I'll drop his email and add the mail list.
>
> Also, for the newly added section I'll change the contact from being both
> me and the mail list to just be the mail list.
>
> -Frank

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH] of: document /sys/firmware/fdt
  2017-06-28 21:49       ` Grant Likely
@ 2017-06-28 22:04         ` Frank Rowand
  0 siblings, 0 replies; 9+ messages in thread
From: Frank Rowand @ 2017-06-28 22:04 UTC (permalink / raw)
  To: Grant Likely; +Cc: Rob Herring, devicetree, Linux Kernel Mailing List

On 06/28/17 14:49, Grant Likely wrote:
> I'm slowly getting back into things and plan to actively participate.
> Please use my ARM address:
> 
> grant.likely@arm.com

OK, I'll do that.

-Frank

> 
> g.
> 
> On Wed, Jun 28, 2017 at 10:46 PM, Frank Rowand <frowand.list@gmail.com> wrote:
>> On 06/22/17 08:23, Rob Herring wrote:
>>> Meant to add Grant.
>>>
>>> On Thu, Jun 22, 2017 at 10:21:24AM -0500, Rob Herring wrote:
>>>> On Tue, Jun 13, 2017 at 09:20:07PM -0700, frowand.list@gmail.com wrote:
>>>>> From: Frank Rowand <frank.rowand@sony.com>
>>>>>
>>>>> Add ABI documentation for /sys/firmware/fdt
>>>>>
>>>>> Update contact for /sys/firmware/devicetree/* to include mail list
>>>>>
>>>>> Signed-off-by: Frank Rowand <frank.rowand@sony.com>
>>>>> ---
>>>>>  Documentation/ABI/testing/sysfs-firmware-ofw | 27 ++++++++++++++++++++++++++-
>>>>>  1 file changed, 26 insertions(+), 1 deletion(-)
>>>>>
>>>>> diff --git a/Documentation/ABI/testing/sysfs-firmware-ofw b/Documentation/ABI/testing/sysfs-firmware-ofw
>>>>> index f562b188e71d..8e700db6c295 100644
>>>>> --- a/Documentation/ABI/testing/sysfs-firmware-ofw
>>>>> +++ b/Documentation/ABI/testing/sysfs-firmware-ofw
>>>>> @@ -1,6 +1,6 @@
>>>>>  What:              /sys/firmware/devicetree/*
>>>>>  Date:              November 2013
>>>>> -Contact:   Grant Likely <grant.likely@linaro.org>
>>>>> +Contact:   Grant Likely <grant.likely@linaro.org>, devicetree@vger.kernel.org
>>>>
>>>> Grant's email is not valid either. I would just drop it unless he wants
>>>> his secretlab.ca email.
>>>>
>>>> Rob
>>>
>>
>> No response from Grant, so I'll drop his email and add the mail list.
>>
>> Also, for the newly added section I'll change the contact from being both
>> me and the mail list to just be the mail list.
>>
>> -Frank
> 

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH] of: document /sys/firmware/fdt
  2017-06-14  4:20 [PATCH] of: document /sys/firmware/fdt frowand.list
  2017-06-14  9:55 ` Mark Rutland
  2017-06-22 15:21 ` Rob Herring
@ 2017-06-29 13:28 ` Grant Likely
  2 siblings, 0 replies; 9+ messages in thread
From: Grant Likely @ 2017-06-29 13:28 UTC (permalink / raw)
  To: Frank Rowand; +Cc: Rob Herring, devicetree, Linux Kernel Mailing List

On Wed, Jun 14, 2017 at 5:20 AM,  <frowand.list@gmail.com> wrote:
> From: Frank Rowand <frank.rowand@sony.com>
>
> Add ABI documentation for /sys/firmware/fdt
>
> Update contact for /sys/firmware/devicetree/* to include mail list
>
> Signed-off-by: Frank Rowand <frank.rowand@sony.com>

Acked-by: Grant Likely <grant.likely@arm.com>

(Apologies for acking from a different address. My ARM email isn't yet
set up to play nice on mailing lists.)

g.

> ---
>  Documentation/ABI/testing/sysfs-firmware-ofw | 27 ++++++++++++++++++++++++++-
>  1 file changed, 26 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/ABI/testing/sysfs-firmware-ofw b/Documentation/ABI/testing/sysfs-firmware-ofw
> index f562b188e71d..8e700db6c295 100644
> --- a/Documentation/ABI/testing/sysfs-firmware-ofw
> +++ b/Documentation/ABI/testing/sysfs-firmware-ofw
> @@ -1,6 +1,6 @@
>  What:          /sys/firmware/devicetree/*
>  Date:          November 2013
> -Contact:       Grant Likely <grant.likely@linaro.org>
> +Contact:       Grant Likely <grant.likely@linaro.org>, devicetree@vger.kernel.org
>  Description:
>                 When using OpenFirmware or a Flattened Device Tree to enumerate
>                 hardware, the device tree structure will be exposed in this
> @@ -26,3 +26,28 @@ Description:
>                 name plus address). Properties are represented as files
>                 in the directory. The contents of each file is the exact
>                 binary data from the device tree.
> +
> +What:          /sys/firmware/fdt
> +Date:          February 2015
> +KernelVersion: 3.19
> +Contact:       Frank Rowand <frank.rowand@sony.com>, devicetree@vger.kernel.org
> +Description:
> +               Exports the FDT blob that was passed to the kernel by
> +               the bootloader. This allows userland applications such
> +               as kexec to access the raw binary. This blob is also
> +               useful when debugging since it contains any changes
> +               made to the blob by the bootloader.
> +
> +               The fact that this node does not reside under
> +               /sys/firmware/device-tree is deliberate: FDT is also used
> +               on arm64 UEFI/ACPI systems to communicate just the UEFI
> +               and ACPI entry points, but the FDT is never unflattened
> +               and used to configure the system.
> +
> +               A CRC32 checksum is calculated over the entire FDT
> +               blob, and verified at late_initcall time. The sysfs
> +               entry is instantiated only if the checksum is valid,
> +               i.e., if the FDT blob has not been modified in the mean
> +               time. Otherwise, a warning is printed.
> +Users:         kexec, debugging
> +
> --
> Frank Rowand <frank.rowand@sony.com>
>

^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2017-06-29 13:29 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-06-14  4:20 [PATCH] of: document /sys/firmware/fdt frowand.list
2017-06-14  9:55 ` Mark Rutland
2017-06-14 10:16   ` Ard Biesheuvel
2017-06-22 15:21 ` Rob Herring
2017-06-22 15:23   ` Rob Herring
2017-06-28 21:46     ` Frank Rowand
2017-06-28 21:49       ` Grant Likely
2017-06-28 22:04         ` Frank Rowand
2017-06-29 13:28 ` Grant Likely

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