On Thu, Jun 15, 2023 at 02:52:54PM -0700, Douglas Anderson wrote: > Trogdor devices use firmware backed by TF-A instead of Qualcomm's > normal TZ. On TF-A we end up mapping memory as cachable. Specifically, > you can see in Trogdor's TF-A code [1] in qti_sip_mem_assign() that we > call qti_mmap_add_dynamic_region() with MT_RO_DATA. This translates > down to MT_MEMORY instead of MT_NON_CACHEABLE or MT_DEVICE. > > **Apparently Qualcomm's normal TZ implementation maps the memory as > non-cachable.** Are you sure about this? From the discussion in the chat the conclusion was that we can check easily for TF-A, but we have absolutely no idea what Qualcomm's firmware implementation does. It might be "broken" the same way and we just have not noticed it yet. I would perhaps just omit this sentence so we don't risk misleading someone with information we're not sure about. :) > > Let's add the "dma-coherent" attribute to the SCM for trogdor. > What about sc7280? I guess they use largely the same TF-A firmware? Thanks, Stephan
