On Wednesday, January 14, 2026 4:26:36 AM CST Konrad Dybcio wrote: > On 1/14/26 4:54 AM, Alex G. wrote: > > On Tuesday, January 13, 2026 8:28:11 AM CST Konrad Dybcio wrote: > >> On 1/9/26 5:33 AM, Alexandru Gagniuc wrote: > >>> Support loading remoteproc firmware on IPQ9574 with the qcom_q6v5_wcss > >>> driver. This firmware is usually used to run ath11k firmware and enable > >>> wifi with chips such as QCN5024. > >>> > >>> When submitting v1, I learned that the firmware can also be loaded by > >>> the trustzone firmware. Since TZ is not shipped with the kernel, it > >>> makes sense to have the option of a native init sequence, as not all > >>> devices come with the latest TZ firmware. > >>> > >>> Qualcomm tries to assure us that the TZ firmware will always do the > >>> right thing (TM), but I am not fully convinced > >> > >> Why else do you think it's there in the firmware? :( > > > > A more relevant question is, why do some contributors sincerely believe > > that the TZ initialization of Q6 firmware is not a good idea for their > > use case? > > > > To answer your question, I think the TZ initialization is an afterthought > > of the SoC design. I think it was only after ther the design stage that > > it was brought up that a remoteproc on AHB has out-of-band access to > > system memory, which poses security concerns to some customers. I think > > authentication was implemented in TZ to address that. I also think that > > in order to prevent clock glitching from bypassing such verification, > > they had to move the initialization sequence in TZ as well. > > I wouldn't exactly call it an afterthought.. Image authentication (as in, > verifying the signature of the ELF) has always been part of TZ, because > doing so in a user-modifiable context would be absolutely nonsensical > > qcom_scm_pas_auth_and_reset() which configures and powers up the rproc > has been there for a really long time too (at least since the 2012 SoCs > like MSM8974) and I would guesstimate it's been there for a reason - not > all clocks can or should be accessible from the OS (from a SW standpoint > it would be convenient to have a separate SECURE_CC block where all the > clocks we shouldn't care about are moved, but the HW design makes more > sense as-is, for the most part), plus there is additional access control > hardware on the platform that must be configured from a secure context > (by design) which I assume could be part of this sequence, based on > the specifics of a given SoC
What was the original use case for the Q6 remoteproc? I see today's use case is as a conduit for ath11k firmware to control PCIe devices. Was that always the case? I imagine a more modern design would treat the remoteproc as untrusted by putting it under a bridge or IOMMU with more strict memory access control, so that firmware couldn't access OS memory. > Konrad
