On 3 February 2021 3:49:14 PM IST, Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx> wrote: >On Wed, 03 Feb 2021 15:42:02 +0530 >Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> wrote: > >> >> >> >> I got more information from the vendor, Telit. The access to the >3rd >> >partition is protected by Trustzone and any access in non privileged >> >mode (where Linux kernel runs) causes kernel panic and the device >> >reboots. > >Out of curiosity, is it a per-CS-line thing or is this section >protected on all CS? > Sorry, I didn't get your question. >> > >> >Ok, so this is not a chip feature but more a host constraint. >> > >> >In this case it would be a good idea to add a host DT property which >> >describes the zone to avoid accessing it. Something like: >> > >> > secure-area/secure-section = <start length>; >> > >> >From the core perspective, we should parse this property early >enough >> >and return -EIO when trying to access this area. > >FWIW, I'm not sure making it part of the core is a good idea, at least >not until we have a different platform with a same needs. The >controller driver can parse it and return -EACCESS (or -EIO) when this >section is accessed. Fine with me. Thanks, Mani -- Sent from my Android device with K-9 Mail. Please excuse my brevity.
