Hi everyone,
We Linux developers seem to have a bit of a love-hate relationship
with ACPI. On the plus side it provides the "standard platform" that
we rely on to support the huge amount of hardware in the x86 ecosystem
It is also the source of much pain due to firmware and DSDT tables
that are either buggy or perform poorly. In the embedded space we've
avoided ACPI entirely by standardizing on the Flattened Device Tree
for hardware discovery. However there are some market segments and use
cases where FDT doesn't solve the problems faced by OEMs, particularly
when the hardware needs to support existing, unmodified OS images.
Some OEMs are looking to implement ACPI on ARM since it is a solution
they are already familiar with. It's becoming clear to me that in the
near future, independent of whether or not we as the Linux community
like it, we are going to start seeing ARM systems that are based on
UEFI and ACPI.
But, to quote h2g2, "Don't Panic." While there are many reasons as to
why ACPI has been the source of pain, at least one of those factors is
under our control. Historically, we as the Linux community have not
been very good at participating or providing leadership as to what the
future of the commodity hardware industry should look like, and the
result is decisions that don't reflect our best interest, sheerly by
omission. (There is an argument that standards setting hasn't been
inclusive either, but I have reason to hope that is neither permanent
nor insurmountable).
So, given that we know that ARM ACPI machines will exist, and given
that we still want to support Linux on these machines, I think it is
absolutely appropriate to start getting involved with both the ACPI
and UEFI standardization processes. I (on behalf of Linaro) will soon
be joining the UEFI ARM Binding Sub Team (ABST), and we already have
representatives from Canonical and Red Hat involved there. I'm also
investigating the possibility of getting involved when the post-ACPI 5
process begins, probably sometime early next year.
In the mean time, I want to start getting prepared by collecting
feedback about the state of ACPI and UEFI now, and what changes we
need to have for ACPI and UEFI to meet our needs in the Linux
ecosystem. Reply to this email with your comments, and I'll start
collating a list that I can discuss with the ACPI and UEFI folks.
For your reference, the current versions of the ACPI and UEFI specs
can be found here[1][2]. The ACPI spec is freely downloadable, but
the UEFI spec requires a click-through license to read.
[1] http://www.acpi.info/DOWNLOADS/ACPIspec40a.pdf
[2] http://www.uefi.org/specs/
I'll kick things off with a few items from my personal list. This list
will grow as I collect feedback and input from all of you.
1) Open Process - Currently the ACPI definition process is entirely
confidential between the 5 APCI member companies (Microsoft, Intel,
Toshiba, HP and Phoenix Technologies), and it remains so until the
Final Draft is proposed to "Contributing Adopters" which is very late
in the process. The current version of the spec is v4.0a[1]. ACPI 5
is currently under final review and will be released sometime late
2011, early 2012.
For us to participate in the ACPI definition, we need to have an open
processes so that open source Linux engineers can participate.
2) Improvements to compliance testing - Several Linux developers have
been doing good work on BIOS/UEFI/ACPI testing and are able to
identify many common bugs in firmware. This is of course valueable to
the Linux ecosystem, but since it is discovering firmware bugs, it is
most likely of high value to all HW and OS vendors. I would like to
see much of the test work that we're currently doing to start
filtering back into the tools that are routinely used by HW vendors as
part of QA testing. Maybe even pushing for an industry wide suite of
compliance tests.
3) Better rules (and testing) on SMM interrupts (or the ARM
equivalent). HW vendors are using SMM to work around hardware bugs or
perform system management tasks independently and transparently from
the operating system. However, poorly implemented firmware will take
the processor away from the OS for unbounded periods of time which is
a deal breaker for any kind of real-time response in the OS. For ARM
systems I would like to see an alternative to compete interruption of
the OS when firmware needs to perform system management tasks.
Cheers,
g.
Hi
Just to confirm what Jean-Christophe said on today's meeting: U-Boot
has disk/part_efi.c added in September 2008:
Add support for CONFIG_EFI_PARTITION (GUID Partition Table)
so it's indeed GPT support.
It's currently being turned on for two NVIDIA Tegra2 boards: Harmony
and Seaboard.
(I didn't try it out.)
One open question we had from last week's meeting is whether we can
have backwards-compatible entries for e.g. boot ROMs in current SoCs as
to use GPT for UEFI compatibility but with the relevant "PC" partitions
entries as to allow booting.
Cheers,
--
Loïc Minier
Meeting minutes are in:
https://wiki.linaro.org/OfficeofCTO/BootArchitecture/2011-10-06
In particular note
- the decision for the focus in a two-pronged approach for short and
long term goals ( see
https://wiki.linaro.org/OfficeofCTO/BootArchitecture/2011-10-06#Minutes
for details, below is just a summary)
+ SHORT TERM pain points are summarized below - the list needs
priorization and to be shown to the TSC so that suitable resources are
assigned to do the work
- support for Uboot
- kernel update process/method
- making every uboot behave the same way
- how does uboot decide what kernel to load - does not have to be
uboot specific fix, could be a script for uboot
- single zImage able to boot on multiple SOCs
- support for grub on uboot.
- Port tianocore as a uboot app
- uboot should understand which is the active partition - or should
have a mechanism to tell the user which is the active partition
+ LONG TERM goals (strategic and design issues): there is a vendors'
interest in standards process - which the Linux community has not been
extremely involved with in the past. So we should work with the
standards - get familiar with the existing standards
For next week - ALL should download and get familiar with ACPI/UEFI
specs (and open firmware ones - if not already familiar with those).
Let me know if there is something missing or wrong in the minutes, I can
update as indicated.
Best regards,
--
Ilias Biris ilias.biris(a)linaro.org
Project Manager, Linaro
M: +358504839608, IRC: ibiris Skype: ilias_biris
Linaro.org│ Open source software for ARM SoCs
Hi all,
I drafted a quick wikipage to explain how to port EDK2 (UEFI Open Source
implementation) on a new ARM Platform :
http://sourceforge.net/apps/mediawiki/tianocore/index.php?title=ArmPlatformP
kg
I am aware this wikipage could require some EDK2 knowledge but I will try to
fill these gaps in the future by creating or referring to wikipages that
explains some of the key EDK2 concepts.
Feel free to directly send me an email if you want more explanations about a
specific concept. That would help to define priorities.
Olivier
https://wiki.linaro.org/OfficeofCTO/BootArchitecture/2011-09-29
Please note the wiki page for the next meeting is set :
https://wiki.linaro.org/OfficeofCTO/BootArchitecture/2011-10-06
Summary of the action points:
- [CARRIEDOVER] Grant to followup the status of Linaro UEFI membership
- [CARRIEDOVER] David Rusling: - Linaro UEFI membership - target Linaro
Connect
- [CARRIEDOVER] Grant to draft a position on secure boot, from the
Linaro perspective, which can be reviewed by Linaro TSC
- [CARRIEDOVER] <tba> Interact with Microsoft on ARM boot interface -
there is some discussion more to say say by around mid October
- [CARRIEDOVER] Grant: Draft DTB recommended practices and getting the
recommended practices document out and merged into a public tree by
Linaro Connect (actually means the week before - as there are other
events before the Connect) INPROGRESS,
- [CARRIEDOVER] Grant: Select date & time for the next f2f meeting (Next
F2F in ELCE in Prague (OCT 26-28) ?)
Option 1: half-day meeting during ELCE, some folks won't make it - this
is the plan to go for Final confirmation
- [CARRIEDOVER] Will: Define SMP boot requirements - spin tables? Target
Linaro Connect. No updates.
- [ACTION] Olivier to send the wiki link with the documentation on how
to port UEFI to new platforms
- [ACTION] Jean-Christophe to send a RFC to the list regarding the
kernel image format and entry protocol
- [ACTION] Jean-Christophe to send some more details the list regarding
the question : is it possible to put the initrd in the DT directly
(similar to putting some firmware in the DT)? Proposal (JC) is to have 2
device trees, one very minimal with the boot arguments and another with
the HW description.
- [ACTION] Jean-Christophe to put an example of the boot sequence to the
mailing list
Best,
--
Ilias Biris ilias.biris(a)linaro.org
Project Manager, Linaro
M: +358504839608, IRC: ibiris Skype: ilias_biris
Linaro.org│ Open source software for ARM SoCs
Hi folks
Etherpad: http://etherpad.osuosl.org/arm-boot-architecture-meeting-notes
I have updated this etherpad with the action points and agenda for
today. Grant, since you will be unable to join, I hope you could give an
update for the actions under your name, I have grouped the action points
under your name at the top of the AP list.
Agenda for today:
* Action items review
* Status updates on DT and UEFI work
* Implementation on other bootloader than the ARM one
* HW platform status
* Android + UEFI status
Anything else to add?
(PLEASE NOTE: As usual, I will be using the etherpad to update the wiki
meeting minutes which is your best reference location to check what was
discussed during any of the meetings.)
Cheers!
--
Ilias Biris ilias.biris(a)linaro.org
Project Manager, Linaro
M: +358504839608, IRC: ibiris Skype: ilias_biris
Linaro.org│ Open source software for ARM SoCs
Is there already support for UEFI Runtime Services in the kernel? If not is this already planned for Linaro?
UEFI Runtime Services are necessary for exchanging NVRAM values with the UEFI environment. These NVRAM values provide the foundation for UEFI spec'ed functionality ranging from boot entry management to key management for secure boot.
Thanks,
Eugene
https://wiki.linaro.org/OfficeofCTO/BootArchitecture/2011-09-22
Please note the new action points at the bottom of the page. Send your
status updates to the list regarding:
- DT and UEFI work
- Implementation on other bootloader than the ARM one
- HW platform status
In addition there was no time to discuss during the last meeting the
Android + UEFI status. Could someone summarize the status there for
the rest of the list?
Thanks,
*************************************
Ilias Biris,
Aallonkohina 2D 19, 02320 Espoo, Finland
Tel: +358 50 4839608 (mobile)
Email: ilias dot biris at linaro dot org
Skype: ilias_biris
*************************************
Hey
As discussed again in today's call, I've pushed a git mirror of edk2's
and edk2-fatdriver2's SVN modules to git.linaro.org.
This is temporary in that:
* the whole history of edk2-fatdriver2 was imported, but only the last
revision of edk2 was imported (a full import is running, but that
will take a while)
* git.linaro.org lacks git-svn and has outbound traffic firewalled; I'm
working with IS to resolve this
These can be used right now, with the caveats that the branches might
be rebased or might move to another host; I'm happy to assist if you
need help moving your patches around when that happens.
The repos are:
git://git.linaro.org/mirror/edk2/edk2.gitgit://git.linaro.org/mirror/edk2/edk2-fatdriver2.git
These were created with:
git svn clone -s \
https://edk2-fatdriver2.svn.sourceforge.net/svnroot/edk2-fatdriver2
edk2-fatdriver2
git svn clone -r 12354 -s \
https://edk2-fatdriver2.svn.sourceforge.net/svnroot/edk2
edk2
Would you need any other SVN module mirrored, or if you have
suggestions about a different set of git-svn options, please get in
touch with me.
Cheers
--
Loïc Minier
Hi everyone,
I'd like to get the date and time sorted out for the next two boot
architecture face-to-face meetings. For the next one, I propose
scheduling it as a 1/2 day summit during LinuxCon & ELC-E in Prague,
Oct 26-28th, or possibly the day before in parallel with kernel
summit. ELC-E I think is an excellent venue since there will be
representatives from a large number of ARM vendors in attendance, as
well as core Linux developers. I believe we'll be able to get a
larger cross-section of the ecosystem there than will be attending
LInaro Connect the week after in Orlando. Does anybody have any
issues with that date? Is there a specific day that works best? I
haven't talked with the Linux Foundation folks yet or looked at the
schedule, but I'll try to choose a time that doesn't conflict with
related presentations.
For the meeting after that, there are two options; either at Linaro
Connect Q1.12, February 6-10, in San Diego (?), or I *think* ELC the
week after and also in San Diego. I need confirmation from the LF
though about the scheduling. I'm leaning toward ELC for this meeting
also for the same reasons as above, but it might be a good strategy to
alternate between Linaro and non-Linaro gatherings. Thoughts?
g.
--
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.
