Hi Julius,
As you were mentioning that the Linux kernel uses /proc/sysrq-trigger
for a similar purpose, I was wondering whether you'd be open to a
solution based on a "DebugFS" entry. As you may have seen on the mailing
list, Olivier posted a proposal for introducing a firmware debug
interface, which has many similarities to how /proc or /sys works in the
kernel world:
https://lists.trustedfirmware.org/pipermail/tf-a/2019-October/000120.html
TF-A patches for this feature are up for review right now and Olivier
has also posted some TF-A Tests patches that demonstrate how this can be
used from normal world. In addition, we are also working on a Linux
driver for this.
As you can imagine, DebugFS uses an SMC interface under the hood
(currently allocated in the SiP range). But being an abstraction over
the SMC layer, which specific SMC function ID is used does not matter so
much and it does not need to be standardized by any Arm specification.
You'd need to mandate all Chrome OS devices to have this DebugFS entry
in the firmware but the backend could vary from platform to platform.
Would that suit your use case?
Regards,
Sandrine
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.
Hi All,
In TF-A we have a large set of build options (over 90). Dependency and incompatibility checks for these are currently done in the Makefile system. This can be hard to follow and difficult to maintain.
We are investigating if there is a better way to describe the build options in a structured way, handle the dependencies/relations between them, and provide a more user-friendly configuration interface.
A possible good solution for this is Kconfig, more specifically a Python implementation called Kconfiglib [1]. We plan to do more prototyping work in this area.
Any feedback or comments on this topic are welcome.
Regards,
Balint
[1] https://github.com/ulfalizer/Kconfiglib
On Tue, Dec 3, 2019 at 4:58 PM Sandeep Tripathy via TF-A
<tf-a(a)lists.trustedfirmware.org> wrote:
>
> Hi,
> system shutdown or system reset PSCI calls are invoked by the last
> core in the system. PSCI lib does not do cache flush for the last core
> /cluster and does not follow the core / cluster power down sequence.
> This may cause issue in a system if the system is not standalone one
> ie if the system is a slave or node in a bigger system with other
> coherent masters/PEs.
>
I am not sure if system off/reset is the right API to call in such a setup.
> Please suggest if the PSCI spec expected 'shutdown/reset/reset2' to
> deliberately skip the core/cluster shutdown sequence.
>
Yes and IIRC this has been discussed in the past[1]. I expect to get some
closure on open question on that thread. Quite a few questions were raised
by few people and I am not sure if all were answered. I need to dig but but
AFAIK it wasn't all answered.
--
Regards,
Sudeep
[1] https://lkml.org/lkml/2019/1/18/16
Hi,
In ATF-A, I usually see below code in psci suspend or off code path:
/* Prevent interrupts from spuriously waking up this cpu */
plat_arm_gic_cpuif_disable();
But per my understanding, before calling psci_suspend(), the NW, e.g linux kernel
has disabled all interrupts from cpu level, so here preventing interrupt is
to prevent the interrupts from secure world?
Another question is: for Cortex A55, this is not necessary. Because
CA55 TRM says when the core_pwrdn_en bit is set, executing WFI automatically
masks all interrupts and wake-up events in the core. Am I right?
Thanks in advance
Hi Soby,
Thanks for your response.
>>it is needed to ensure the ordering of the succeeding sev().
Agree. Thanks for the clarification.
>>Was this an issue that actually manifested on a hardware or is this
something that you caught while reviewing the code?
Noticed it while reviewing code and I have not observed it on hardware.
Thanks
-Raghu
On November 26, 2019 at 8:55 AM, Soby Mathew <Soby.Mathew(a)arm.com> wrote:
On 26/11/2019 16:30, Raghupathy Krishnamurthy via TF-A wrote:
Hello!
Reposting this from (https://developer.trustedfirmware.org/T589).
bakery_lock_get() uses a dmbld() after lock acquisition which is insufficient in a lock acquire situation. With just dmbld(), stores in a critical section can be reordered before the dmbld() and indeed before the lock acquisition has taken place. similarly, bakery_lock_release() only uses dmbst(). A load in the critical section could be reordered after the dmbst() and write to the lock data structure releasing the lock. This is likely less of a problem but lock release needs to provide release semantics, and dmbst() is insufficient. For ex: A load in the critical section of CPU1 can be reordered after the store for the lock release, and it could read from a store that is executed on CPU2 in the same critical section, since CPU2 saw the store for the lock release first, and raced into the critical section.
Hi Raghu,
You are right on this. The dmbld() and dmbst() does not provide
sufficient guarantees in the cases you mention.
Was this an issue that actually manifested on a hardware or is this
something that you caught while reviewing the code ?
Also the dsb() after the write to the lock seems unnecessary. Am I missing something here ? It looks like the same issue is present even in bakery_lock_normal.
If you are referring to the dsb() at this line :
https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/tree/lib/locks/…
it is needed to ensure the ordering of the succeeding sev().
Best Regards
Soby Mathew
Thanks
Raghu
Hi Sandeep
> -----Original Message-----
> From: TF-A <tf-a-bounces(a)lists.trustedfirmware.org> On Behalf Of Sandeep
> Tripathy via TF-A
> Sent: 03 December 2019 16:59
>
> Hi,
> system shutdown or system reset PSCI calls are invoked by the last core in
> the system.
That may be the case in practice but these functions can be called by any core in the system at any time, not just the last core.
> PSCI lib does not do cache flush for the last core /cluster and
> does not follow the core / cluster power down sequence.
Correct. Not only that, it doesn't do anything with the other cores in the system that may be running at that time.
> This may cause issue in a system if the system is not standalone one ie if
> the system is a slave or node in a bigger system with other coherent
> masters/PEs.
>
What issue specifically? Are the other coherent masters expecting to have the same view of the node's memory that the node had prior to calling system off/suspend? If so, then the node is not really independent to the wider system and system off/reset are probably not the right calls to use. Perhaps SYSTEM_SUSPEND is what you're looking for? That function requires all other cores to be off before the call and will perform cache maintenance on the last core.
> Please suggest if the PSCI spec expected 'shutdown/reset/reset2' to
> deliberately skip the core/cluster shutdown sequence.
>
Yes, the spec was deliberately relaxed between version 0.2 and 1.0 to allow implementations to just "pull the plug" since there would be no observable difference to the normal world caller between this behaviour and attempting to shutdown cleanly, which would be difficult and inherently racy anyway.
> Otherwise in case it makes sense following is a patch to take care of this.
> https://review.trustedfirmware.org/#/c/TF-A/trusted-firmware-a/+/2364/
> issue: https://developer.trustedfirmware.org/T566
Thanks but I don't think we want this.
Regards
Dan.
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Hi,
system shutdown or system reset PSCI calls are invoked by the last
core in the system. PSCI lib does not do cache flush for the last core
/cluster and does not follow the core / cluster power down sequence.
This may cause issue in a system if the system is not standalone one
ie if the system is a slave or node in a bigger system with other
coherent masters/PEs.
Please suggest if the PSCI spec expected 'shutdown/reset/reset2' to
deliberately skip the core/cluster shutdown sequence.
Otherwise in case it makes sense following is a patch to take care of this.
https://review.trustedfirmware.org/#/c/TF-A/trusted-firmware-a/+/2364/
issue: https://developer.trustedfirmware.org/T566
Thanks
Sandeep
Hello Sumit,
Sorry for not getting back to you earlier on this. I started looking at
your patches and although I've not completely got my head around them
yet, I've got some early comments and questions. I've tried to classify
them by themes below.
First of all, let me say that I'm no security expert and I did not know
about the concept of authenticated encryption/decryption before looking
at your patches. I spent a couple of hours reading about such algorithms
in general and AES-GCM in particular. Most of what I've learned so far
is based on my understanding of RFC 5116 [1].
What's the motivation for choosing GCM to start with? I've seen that it
is free of patent [2], which I am guessing was a strong argument for it.
I've also read that it is supposed to be quite lightweight and can take
full advantage of parallel processing, although I've not looked into the
details. Were these the reasons? Any other reasons?
Key management
--------------
fip_file_read() retrieves the key from the platform and stores it in a
buffer on the stack. I don't see any code wiping it out of memory once
we're done with it. Did I miss it? Unlike the root of trust public key,
this is a (symmetric) secret key so it is sensitive data that we must
not leave for grabs, even if the stack is in Trusted RAM and that it's
likely to be overwritten by subsequent stack usage.
Also, I am still trying to get my head around how this would integrate
with a cryptographic engine where the key does not leave the chip. I can
imagine that we could get the address of the encrypted firmware image
from the FIP, pass that to a cryptographic engine, request it to decrypt
it and store the result somewhere in Trusted RAM. In this case, we
wouldn't call plat_get_fip_encryption_key(). Do you have any idea how we
would pull this off? Like how the different modules (IO layer, crypto
module, image parser module, ...) would integrate together?
I have some concerns around the generation of the initialization vectors
in the encrypt_fw tool. Right now, IVs are simply a random sequence of
bytes (obtained through a call to OpenSSL's RAND_bytes() API). Now, I
would imagine that RAND_bytes() is typically based on a good random
number generator and thus will generate different sequences every time
it is called. At least, as long as it is called from the same machine
every time. But what if we encrypt a new FIP bundle from a different
machine, say in the context of a firmware update? Is it not possible
that it might choose the same IV out of bad luck?
Perhaps that's an issue left to provisioning/manufacturing time and is
out of the scope here. But it worries me because AFAIU, the security of
AES-GCM is critically undermined if the same nonce is used multiple
times with the same key (see section 5.1.1. "Nonce reuse" in RFC 5116).
If the encryption key is the SSK (rather than the BSSK) then I guess the
probability is even higher, as it is shared amongst a class of devices.
Impact on memory footprint and performance
------------------------------------------
Do you know what the performance impact is when this feature is enabled
in TF-A, to decrypt images at boot time? Obviously it depends on the
platform and whether there is a dedicated cryptographic engine, and I
suppose you cannot really get any relevant measurements out of QEMU but
I would be interested if you've got any rough numbers.
And what's the memory footprint impact? IIUC, AES-GCM almost does not
inflate the size of the data it encrypts. The size of the ciphertext
seems to be the same as the plaintext + the size of the authentication
tag. So I guess there's no real impact on flash storage and Trusted RAM
usage to hold decrypted firmware. But what about the mbedTLS primitives
to decrypt the images? How much code and data does this add?
encrypt_fw tool
---------------
We have some floating ideas around re-implementing the tools (fiptool,
certtool) in a scripting language (possibly python) in the future and
also doing a better job at sharing a common description of the list of
images to boot/authenticate between the firmware and the host tools. But
we're not there yet, so I agree that implementing this new tool in C
from the same "mold" as fiptool and certtool is what makes the most
sense today. It's just another tool we will have to rework if and when
we get there.
I did not understand why this new tool needs to know what image it is
encrypting. For example, one possible invocation could be:
tools/encrypt_fw/encrypt_fw \
-k 1234567890abcdef1234567890abcdef1234567890abcdef1234567890abcdef \
--soc-fw bl31.bin \
--soc-fw-enc bl31_enc.bin \
--tos-fw bl32.bin \
--tos-fw-enc bl32_enc.bin
Why not invoking the tool once per image instead? As in:
encrypt_fw -k key -in ifile -out ofile
for BL31, then for BL32? Does the tool do anything different based on
the type of image it receives?
Regards,
Sandrine
[1] https://tools.ietf.org/html/rfc5116
[2]
https://csrc.nist.gov/csrc/media/projects/block-cipher-techniques/documents…
Hi All,
The buildsystem of TF-A became complex and loaded with technical debt during the years, and it's time to do something about this.
We made some plans and prototyping work to move to a CMake based solution and we would like to get feedback on the idea.
Why CMake?
In summary CMake is a mature tool having a wide acceptance in C and C++ projects.
Also it has benefits of decreasing fragmentation in the developer community if we sync up with TF-M.
How will it happen?
This will be a slow process where the old build system will co-exist for a period with the new one. How long that period will be is an open question.
For a more detailed summary please see https://developer.trustedfirmware.org/w/tf_a/cmake-buildsystem-proposal/
The design discussion will follow the design review proposal process of TF.org, as described on this page:
https://ci.trustedfirmware.org/job/tf-m-build-test-nightly/lastSuccessfulBu…
You can find the patch for capturing the design decisions and discussion here: https://review.trustedfirmware.org/#/c/TF-A/trusted-firmware-a/+/2662/
If you would like to contribute or have an opinion or any ideas please reply to this email or add a comment on Gerrit (link above).
Regards,
Balint
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.
On 26/11/2019 16:30, Raghupathy Krishnamurthy via TF-A wrote:
> Hello!
>
> Reposting this from (https://developer.trustedfirmware.org/T589).
>
> bakery_lock_get() uses a dmbld() after lock acquisition which is insufficient in a lock acquire situation. With just dmbld(), stores in a critical section can be reordered before the dmbld() and indeed before the lock acquisition has taken place. similarly, bakery_lock_release() only uses dmbst(). A load in the critical section could be reordered after the dmbst() and write to the lock data structure releasing the lock. This is likely less of a problem but lock release needs to provide release semantics, and dmbst() is insufficient. For ex: A load in the critical section of CPU1 can be reordered after the store for the lock release, and it could read from a store that is executed on CPU2 in the same critical section, since CPU2 saw the store for the lock release first, and raced into the critical section.
Hi Raghu,
You are right on this. The dmbld() and dmbst() does not provide
sufficient guarantees in the cases you mention.
Was this an issue that actually manifested on a hardware or is this
something that you caught while reviewing the code ?
> Also the dsb() after the write to the lock seems unnecessary. Am I missing something here ? It looks like the same issue is present even in bakery_lock_normal.
>
If you are referring to the dsb() at this line :
https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/tree/lib/locks/…
it is needed to ensure the ordering of the succeeding sev().
Best Regards
Soby Mathew
> Thanks
> Raghu
>
Hello!
Reposting this from (https://developer.trustedfirmware.org/T589).
bakery_lock_get() uses a dmbld() after lock acquisition which is insufficient in a lock acquire situation. With just dmbld(), stores in a critical section can be reordered before the dmbld() and indeed before the lock acquisition has taken place. similarly, bakery_lock_release() only uses dmbst(). A load in the critical section could be reordered after the dmbst() and write to the lock data structure releasing the lock. This is likely less of a problem but lock release needs to provide release semantics, and dmbst() is insufficient. For ex: A load in the critical section of CPU1 can be reordered after the store for the lock release, and it could read from a store that is executed on CPU2 in the same critical section, since CPU2 saw the store for the lock release first, and raced into the critical section. Also the dsb() after the write to the lock seems unnecessary. Am I missing something here ? It looks like the same issue is present even in bakery_lock_normal.
Thanks
Raghu
Hi all,
I finally got round to collating links to all TF-A public presentations done over the years in our wiki page here
https://developer.trustedfirmware.org/w/tf_a/
I intend to keep the list updated with all future appearances as well.
Let me know if you spot any error or inconsistency.
Thanks
Matteo
Hi everyone,
Please let me introduce the `Property Access Layer` prototype:
The Property Access Layer (PAL) is an abstraction layer for platform specific data, allowing a "property" to be queried and a value retrieved without the requesting entity knowing what backing store is being used to hold the data. It is used to bridge new and old ways of providing platform-specific data:
Today, information like the Chain of Trust is held within several, nested platform-defined tables. In the future, it may be provided as part of a device tree blob, along with the information about images to load.
Introducing this abstraction layer will make migration easier and will preserve functionality for platforms that cannot / don't want to use device tree.
Please have a look at the patches: https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/2559/1
Regards,
Louis
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Hello,
This message is to provide advance notice that the experimental Secure Partition Manager (SPM) component - based around the SPCI Alpha 1 specification - will be removed from the codebase within the next few weeks. This component was deprecated for the v2.2 release. Normally a component stays in the codebase for one full release cycle after being deprecated but that does not apply to experimental and/or prototype features such as this one.
The intention is not to replace this component directly with a similar SPM component but to instead implement an EL3 SPCI dispatcher component that enables the use of secure partitions with an SPM at either S-EL1 or at S-EL2 (v8.4 or later). This dispatcher would be compliant with the latest public draft of the Secure Partition Client Interface (SPCI) specification at the time.
Please note that the SPM-MM (Management Mode) component is *not* going to be removed as part of this work.
If you have any questions or concerns about this change then please get in touch either via this mailing list or via your Arm partner manager (where applicable).
Thanks,
Paul
Hi,
Just to clarify a little bit more.
There is no link here about a 32/64 bit architecture. The content of
this change is to take care about new memory introduce (mtd devices)
that are not based on size * LBA (where LBA=512) but size * LBA where
(LBA=1) and in such case, the size could exceed the 4GB. It is not
platform dependent and not architecture dependent, it's link to the
connected MTD device only. I'm not sure that a new type is useful except
if you want a type is modified regarding a platform flag such as
USE_LARGE_MTD_DEVICE.
Hope it's more clear.
BR,
Lionel
On 11/5/19 3:20 PM, Gyorgy Szing via TF-A wrote:
> Hi,
>
> I did not investigated all the details so what stays below may contain mistakes, but still I would like to add some comments.
>
> "using a type for the offset"
> The type we use for this purpose seems to be a configuration parameter for the IO layer as it depends on the upper layer being used with the IO library. For example libc uses "long int" to specify the file offset (fseek, ftell), using a different type while running below libc does not seem to be a good idea.
> The best option seems to be to define a type like (as Olivier mentioned) lib/zlib does. How we set this configuration parameter during the build is a question. The offset type could be dictated by the platform, the architecture (aarch32 or aarch64) or by the user. Which one is worth to implement needs investigation.
>
> If it is a good idea to use the same name "off_t" as zlib uses (or even the same type) is be questionable. It may give us more flexibility if we use a dedicated name, and the configuration maps the IO type to the one used by the upper layer.
>
> "32 bit backward compatibility"
> Another angle worth to consider is the 32/64 bit compatibility. I.e.: newlib can use 64 bit offsets even on 32 bit architectures, and they use some wrappers to maintain binary compatibility with old builds. When built in a compatible manner, functions using the standardized names use 32 bit wide offsets and call the real 64 bit implementation as a wrapper.
> To solve compatibility issues we could use a similar pattern. Instead of changing the existing function, we could add a new one (i.e. seek64). Then new 64 bit aware code could use the new function if available, and legacy code could call the old one. Longer term it is an option to deprecate the 32 bit version.
>
> "use stdint.h types"
> And a finally: when selecting the type used for off_t (or whatever we are going to call it) please consider using stdint.h types (i.e. int_fast64_t).
>
> /George
>
> -----Original Message-----
> From: TF-A <tf-a-bounces(a)lists.trustedfirmware.org> On Behalf Of Olivier Deprez via TF-A
> Sent: 25 October 2019 14:42
> To: tf-a(a)lists.trustedfirmware.org; Lionel DEBIEVE <lionel.debieve(a)st.com>
> Subject: Re: [TF-A] [RFC] BL2 MTD frameworks
>
> Hi Lionel,
>
> On https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/2283
> I'm extending the discussion to the TF-A ML, to get people's opinion.
>
> The idea is to extend the io_seek offset parameter from ssize_t to unsigned long long.
> There are indeed good reasons for that as flash storage density grows over the years.
>
> Now on the change, the struct io_dev_funcs seek function pointer is generic for the whole codebase / drivers.
> So currently the change breaks the builds for at least rcar, stratix10 (did not check others from that point).
>
> An alternative is defining offset as an off_t type which is ssize_t by default, and only unsigned long long based on the platform (using _FILE_OFFSET_BITS=64). This pattern actually already exists in lib/zlib
>
> Other option is to change the generic prototype for all platform drivers (then we ensure all platforms build and supply platform patches).
>
> What do ML people think?
>
> Regards,
> Olivier.
>
>
>
> ________________________________
> From: TF-A <tf-a-bounces(a)lists.trustedfirmware.org> on behalf of Lionel DEBIEVE via TF-A <tf-a(a)lists.trustedfirmware.org>
> Sent: 18 October 2019 17:26
> To: tf-a(a)lists.trustedfirmware.org <tf-a(a)lists.trustedfirmware.org>
> Subject: [TF-A] [RFC] BL2 MTD frameworks
>
> Hello Maintainers,
>
> I've sent a patch series around MTD framework management into BL2 stage (cf https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/2283).
>
> This patch series will add following frameworks:
>
> - a raw NAND framework implementation to support SLC NAND devices. Current implementation is limited to read operations without ECC corrections. Overrides are available to use hardware ECC from controller or low-level drivers. It also supports ONFI detection management but this can also be disabled or overridden by platform specific data.
> - a SPI-MEM framework (inspired from kernel/u-boot implementation) that encapsulates all SPI operations to SPI low level drivers.
> - a SPI-NAND framework based on SPI-MEM to support SPI NAND devices. This framework is also limited to the read operation. It uses single command, address and data bus width as legacy but can be overridden by platform.
> - a SPI-NOR framework based on SPI-MEM to manage SPI NOR devices. It is also limited to read operations using single command, address and data bus width as legacy (override still possible by platform). The framework embeds some specific implementations for manufacturers specific behavior in case of quad mode configuration activation.
>
> This patch series also includes:
>
> - a new io_mtd interface to manage a generic access to all these frameworks.
> - a NAND core driver that accesses independently to raw NAND or SPI-NAND framework. This core driver requires a scratch buffer defined by platform to manage unaligned pages (could be defined to 0 in case of aligned page) and limits access to a single NAND instance management.
> - a complete integration is available based on STM32MP1 platform.
>
> Tests have been performed with the following devices:
>
> SLC NAND:
> - Micron MT29F8G08ABACAH4 (ONFI)
> - Micron MT29F8G16ABACAH4 (ONFI)
> - Toshiba TH58NVG3S0HTAI0 (Non ONFI)
> - Toshiba TC58BVG1S3HTAI0 (On die ECC)
>
> SPI NOR:
> - Macronix MX25L51245G
> - Cypress/Spansion S25FL512
> - Micron n25q512ax3
>
> SPI-NAND:
> - Micron MT29F2G01ABAGD
>
> Waiting for your comments.
>
> Best regards, Lionel
> --
> TF-A mailing list
> TF-A(a)lists.trustedfirmware.org
> https://lists.trustedfirmware.org/mailman/listinfo/tf-a
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Hello all,
As you may know, the Trusted Board Boot (TBB) code relies on the
platform to define a chain of trust (CoT). Today, the only example of
CoT present in the code base is the one used on Arm platforms, which is
described:
- in the TBBR specification [1].
- in the TF-A documentation [2] [3].
The entire TBBR CoT is built upon the root-of-trust public key (ROTPK),
which is used to authenticate all subsequent firmware binaries and
certificates, either directly or indirectly through some intermediate
certificates.
The TBBR CoT is only one example of a possible certificate chain and key
ownership model. It might not suit all platforms and market segments but
the TBBR implementation in TF-A leaves some freedom for other CoTs.
Today, we are publishing some proof-of-concept code that shows one way
the existing TBBR CoT may be modified in order to detach the BL33 image
from the rest of the CoT. This effectively splits it into 2 CoTs:
- 1 CoT for all secure world images (BL2, BL31, BL32).
- 1 CoT for the normal world bootloader (BL33).
If you are interested, please have a look at the related patch as well
as the companion documentation:
https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/2443https://developer.trustedfirmware.org/w/tf_a/poc-multiple-signing-domains/
Note that at this stage, this is only prototype code and we do not plan
to integrate it in the code base as is, because it does not implement
what we would consider as a clean solution and uses a number of
workarounds. We are considering cleaning this patch up and providing it
as an alternate CoT on FVP platform in the future.
For now, the intent is to provide some material, which we can base a
discussion on. We're hoping to gather feedback from interested parties
on the suitability of this approach.
Regards,
Sandrine
[1]
https://developer.arm.com/docs/den0006/d/trusted-board-boot-requirements-cl…
(see page 21)
[2]
https://trustedfirmware-a.readthedocs.io/en/latest/design/trusted-board-boo…
[3]
https://trustedfirmware-a.readthedocs.io/en/latest/design/auth-framework.ht…
Hi,
I did not investigated all the details so what stays below may contain mistakes, but still I would like to add some comments.
"using a type for the offset"
The type we use for this purpose seems to be a configuration parameter for the IO layer as it depends on the upper layer being used with the IO library. For example libc uses "long int" to specify the file offset (fseek, ftell), using a different type while running below libc does not seem to be a good idea.
The best option seems to be to define a type like (as Olivier mentioned) lib/zlib does. How we set this configuration parameter during the build is a question. The offset type could be dictated by the platform, the architecture (aarch32 or aarch64) or by the user. Which one is worth to implement needs investigation.
If it is a good idea to use the same name "off_t" as zlib uses (or even the same type) is be questionable. It may give us more flexibility if we use a dedicated name, and the configuration maps the IO type to the one used by the upper layer.
"32 bit backward compatibility"
Another angle worth to consider is the 32/64 bit compatibility. I.e.: newlib can use 64 bit offsets even on 32 bit architectures, and they use some wrappers to maintain binary compatibility with old builds. When built in a compatible manner, functions using the standardized names use 32 bit wide offsets and call the real 64 bit implementation as a wrapper.
To solve compatibility issues we could use a similar pattern. Instead of changing the existing function, we could add a new one (i.e. seek64). Then new 64 bit aware code could use the new function if available, and legacy code could call the old one. Longer term it is an option to deprecate the 32 bit version.
"use stdint.h types"
And a finally: when selecting the type used for off_t (or whatever we are going to call it) please consider using stdint.h types (i.e. int_fast64_t).
/George
-----Original Message-----
From: TF-A <tf-a-bounces(a)lists.trustedfirmware.org> On Behalf Of Olivier Deprez via TF-A
Sent: 25 October 2019 14:42
To: tf-a(a)lists.trustedfirmware.org; Lionel DEBIEVE <lionel.debieve(a)st.com>
Subject: Re: [TF-A] [RFC] BL2 MTD frameworks
Hi Lionel,
On https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/2283
I'm extending the discussion to the TF-A ML, to get people's opinion.
The idea is to extend the io_seek offset parameter from ssize_t to unsigned long long.
There are indeed good reasons for that as flash storage density grows over the years.
Now on the change, the struct io_dev_funcs seek function pointer is generic for the whole codebase / drivers.
So currently the change breaks the builds for at least rcar, stratix10 (did not check others from that point).
An alternative is defining offset as an off_t type which is ssize_t by default, and only unsigned long long based on the platform (using _FILE_OFFSET_BITS=64). This pattern actually already exists in lib/zlib
Other option is to change the generic prototype for all platform drivers (then we ensure all platforms build and supply platform patches).
What do ML people think?
Regards,
Olivier.
________________________________
From: TF-A <tf-a-bounces(a)lists.trustedfirmware.org> on behalf of Lionel DEBIEVE via TF-A <tf-a(a)lists.trustedfirmware.org>
Sent: 18 October 2019 17:26
To: tf-a(a)lists.trustedfirmware.org <tf-a(a)lists.trustedfirmware.org>
Subject: [TF-A] [RFC] BL2 MTD frameworks
Hello Maintainers,
I've sent a patch series around MTD framework management into BL2 stage (cf https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/2283).
This patch series will add following frameworks:
- a raw NAND framework implementation to support SLC NAND devices. Current implementation is limited to read operations without ECC corrections. Overrides are available to use hardware ECC from controller or low-level drivers. It also supports ONFI detection management but this can also be disabled or overridden by platform specific data.
- a SPI-MEM framework (inspired from kernel/u-boot implementation) that encapsulates all SPI operations to SPI low level drivers.
- a SPI-NAND framework based on SPI-MEM to support SPI NAND devices. This framework is also limited to the read operation. It uses single command, address and data bus width as legacy but can be overridden by platform.
- a SPI-NOR framework based on SPI-MEM to manage SPI NOR devices. It is also limited to read operations using single command, address and data bus width as legacy (override still possible by platform). The framework embeds some specific implementations for manufacturers specific behavior in case of quad mode configuration activation.
This patch series also includes:
- a new io_mtd interface to manage a generic access to all these frameworks.
- a NAND core driver that accesses independently to raw NAND or SPI-NAND framework. This core driver requires a scratch buffer defined by platform to manage unaligned pages (could be defined to 0 in case of aligned page) and limits access to a single NAND instance management.
- a complete integration is available based on STM32MP1 platform.
Tests have been performed with the following devices:
SLC NAND:
- Micron MT29F8G08ABACAH4 (ONFI)
- Micron MT29F8G16ABACAH4 (ONFI)
- Toshiba TH58NVG3S0HTAI0 (Non ONFI)
- Toshiba TC58BVG1S3HTAI0 (On die ECC)
SPI NOR:
- Macronix MX25L51245G
- Cypress/Spansion S25FL512
- Micron n25q512ax3
SPI-NAND:
- Micron MT29F2G01ABAGD
Waiting for your comments.
Best regards, Lionel
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Hi all,
We are introducing a new "memory map" tool part of the build system.
The tool parse the blx.map files and print a representation of the memory layout for the latest build.
It can be invoked by adding "memmap" in the make build command.
If you are interested, please have a look at the related patch:
https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/2413/1
Regards,
Louis
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.
Hi All,
We are proposing a new firmware debug interface in the form of a "debug filesystem".
The intent is to expose live firmware data or firmware driver HAL to the upper layers, in debug builds.
For people interested, please review and comment the design proposal:
https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/2381
The design is not closed, the intent is to collect opinions, and have a discussion on options and implications.
Thanks & Regards,
Olivier.
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.
Hi Lionel,
On https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/2283
I'm extending the discussion to the TF-A ML, to get people's opinion.
The idea is to extend the io_seek offset parameter from ssize_t to unsigned long long.
There are indeed good reasons for that as flash storage density grows over the years.
Now on the change, the struct io_dev_funcs seek function pointer is generic for the whole codebase / drivers.
So currently the change breaks the builds for at least rcar, stratix10 (did not check others from that point).
An alternative is defining offset as an off_t type which is ssize_t by default, and only unsigned long long based on the platform (using _FILE_OFFSET_BITS=64). This pattern actually already exists in lib/zlib
Other option is to change the generic prototype for all platform drivers (then we ensure all platforms build and supply platform patches).
What do ML people think?
Regards,
Olivier.
________________________________
From: TF-A <tf-a-bounces(a)lists.trustedfirmware.org> on behalf of Lionel DEBIEVE via TF-A <tf-a(a)lists.trustedfirmware.org>
Sent: 18 October 2019 17:26
To: tf-a(a)lists.trustedfirmware.org <tf-a(a)lists.trustedfirmware.org>
Subject: [TF-A] [RFC] BL2 MTD frameworks
Hello Maintainers,
I've sent a patch series around MTD framework management into BL2 stage (cf https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/2283).
This patch series will add following frameworks:
- a raw NAND framework implementation to support SLC NAND devices. Current implementation is limited to read operations without ECC corrections. Overrides are available to use hardware ECC from controller or low-level drivers. It also supports ONFI detection management but this can also be disabled or overridden by platform specific data.
- a SPI-MEM framework (inspired from kernel/u-boot implementation) that encapsulates all SPI operations to SPI low level drivers.
- a SPI-NAND framework based on SPI-MEM to support SPI NAND devices. This framework is also limited to the read operation. It uses single command, address and data bus width as legacy but can be overridden by platform.
- a SPI-NOR framework based on SPI-MEM to manage SPI NOR devices. It is also limited to read operations using single command, address and data bus width as legacy (override still possible by platform). The framework embeds some specific implementations for manufacturers specific behavior in case of quad mode configuration activation.
This patch series also includes:
- a new io_mtd interface to manage a generic access to all these frameworks.
- a NAND core driver that accesses independently to raw NAND or SPI-NAND framework. This core driver requires a scratch buffer defined by platform to manage unaligned pages (could be defined to 0 in case of aligned page) and limits access to a single NAND instance management.
- a complete integration is available based on STM32MP1 platform.
Tests have been performed with the following devices:
SLC NAND:
- Micron MT29F8G08ABACAH4 (ONFI)
- Micron MT29F8G16ABACAH4 (ONFI)
- Toshiba TH58NVG3S0HTAI0 (Non ONFI)
- Toshiba TC58BVG1S3HTAI0 (On die ECC)
SPI NOR:
- Macronix MX25L51245G
- Cypress/Spansion S25FL512
- Micron n25q512ax3
SPI-NAND:
- Micron MT29F2G01ABAGD
Waiting for your comments.
Best regards, Lionel
--
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Hi Feng,
user-guide.rst references GCC 9.1 and later versions. The code was also tested with GCC 10.0.0.
Regards.
Alexei
________________________________
From: TF-A <tf-a-bounces(a)lists.trustedfirmware.org> on behalf of Chen Feng via TF-A <tf-a(a)lists.trustedfirmware.org>
Sent: 24 October 2019 14:32
To: tf-a(a)lists.trustedfirmware.org <tf-a(a)lists.trustedfirmware.org>
Subject: [TF-A] compile toolchain
hi expects,
from the atf2.2 release notes,I can see the tf-a already supported pac bti and mte feature. I want to enable and test it on fvp platform.
I want to know which tool chain to use for compiling code for theses.
Cheers
Feng
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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.
hi expects,
from the atf2.2 release notes,I can see the tf-a already supported pac bti and mte feature. I want to enable and test it on fvp platform.
I want to know which tool chain to use for compiling code for theses.
Cheers
Feng