[Sound-open-firmware] Distribution of sof firmware and tplg files

[Jaroslav Kysela]

Dne 13. 01. 20 v 16:47 Pierre-Louis Bossart napsal(a):
> 
> 
>> The all-in-one package is useful for:
>>
>> 1) debugging .ldc files - they don't belong to any of the upstream repos
> 
> I just want to clarify something on those files: Rather than adding
> strings to all our traces, when generating the firmware we strip them
> out to reduce the firmware footprint, and the actual strings are stored
> in the ldc. When you want to extract traces, the sof-logger tool
> substitutes the codes for human-readable strings. The ldc files only
> existing in relation with the initial firmware they were extracted from.
> 
> I don't see at all why these ldc files can't be distributed along with
> the firmware. In fact, we could change the firmware format and add them
> in a single file, which would be stripped during firmware download and
> you'd not even know about it...

I see, but why to carry files which are not required to boot linux in the 
linux-firmware? It's only an extra bloat which only few users will use. You 
can integrated it to one file, of course. But ... you removed this info for 
the exactly similar reason, don't you? The extra debugging information is not 
required for the standard runtime.

>> 2) SOF release - you have full control to put all things together and
>>      we can use this as a reference; eventually, we can update the community
>>      integration repos from this
> 
> So we are talking about multiple integration channels, that's not so
> good for us

We always hit this. Think what's good for all users. It's easy to assign the 
.ldc file to the firmware file using some checksums or so. And, who are users 
of this? Few users who want to debug problem or maintainers who can point to 
the .ldc file. Also, if you have .ldc, you need to have the trace utility 
(binary). Perhaps, you can create an extra debugging package with all .ldc 
files for all released firmwares and find a way at runtime to determine the 
loaded firmware and select the proper .ldc automatically. It's just another hint.

>> 3) extra firmware files (not used by default kernel configuration / code)
> 
> We don't have such cases at the moment.

You do have. In the Liam's linux-firmware repository, there are several old or 
special 1.3 firmware files, which are not directly referred from the driver. 
The user must change the kernel configuration using the kernel / module 
parameters:

https://github.com/thesofproject/linux-firmware/commit/beff732e6642bd77dac5dd08514264f055fc4d10#r366567340

Example: File: intel/sof/cml/intel/sof-cml-v1.3-0f73628.ri ????

>> It does not mean that the stable code should not be pushed to the
>> "integration" repositories (where the code is merged from the multiple
>> sources). But in case of issues (debugging) or if you have special users
>> (firmware for special hardware variants requiring the extra kernel
>> parameters / setup), the users might look back to the all-in-one repo
>> (SOF project release).
> 
> I would really like to have all .ldc distributed by default so that we
> can ask for traces without requiring any install shenanigans. People are
> able to use alsa-info.sh, and I consider the .ldc files as a extension
> helping provide DSP traces.

Yes, but it's debugging and there is no standard for this. The extra debugging 
package with .ldc and the trace utility for SOF might be really a good thing.

					Jaroslav

-- 
Jaroslav Kysela <perex at perex.cz>
Linux Sound Maintainer; ALSA Project; Red Hat, Inc.