Hi Bryan! On Wed, 2025-09-10 at 07:53 -0500, [email protected] wrote: > > > > > > The watchdog requires to have the MCU ESM error source enabled to > > > > > > trigger a system reboot. When booting HS-SE (security enforced) > > > > > > devices, the MMR registers are locked again and all write commands > > > > > > are simply ignored. > > > > > > > > > > > > Unlock the MMR registers again to successfully enable the MCU ESM > > > > > > source. > > > > > I'm just curious, could you please elaborate a bit, where the > > > > > registers > > > > > are being locked again if they are being unlocked by ctrl_mmr_unlock() > > > > > in board_init_f() before enable_mcu_esm_reset()? > > > > > > > > > > Is it TIFS firmware? > > > > > What else could be affected? > > > > > Do we expect to leave General Purpose Control Registers unlocked > > > > > when we return from board_init_f()? > > > > > Does it mean that the whole ctrl_mmr_unlock() has to be re-done > > > > > after k3_sysfw_loader() call? > > > > > > > > I really can't tell why those registers are locked again. I figured out > > > > they're only locked again after loading the TIFS firmware on HS-SE > > > > devices. > > > > So, I also assume the firmware itself locks those registers again as > > > > part of > > > > a secure/security feature. > > > > > > Hmm yeah this is likely a bug or a config issue. Ideally we > > > (U-Boot/Linux) should be in complete control of when these are locked or > > > unlocked. TIFS or DM shouldn't be anywhere near these MMRs. > > > > > > > > > > > The A53 SPL will unlock those registers again, which will be permanent. > > > > Only > > > > the watchdog is problematic because enable_mcu_esm_reset is currently > > > > only > > > > called in the R5 SPL (config only enabled in the R5 SPL defconfig). > > > > > > > > BTW: We have seen the same behavior with the AM68A/J721S2. > > > > > > Hmm this is strange. > > > > Thanks for your assessment! > > Do you know who can be contacted at TI regarding this possible problem in > > TIFS firmware? Maybe this has to be fixed in TIFS firmware indeed? > > I've started creating some noise internally to see if we can debug this > faster. Most of these teams are fairly insulated from the outside world > and can only be reached via e2e tickets.
Thanks for looking into this! I read it as if we would not need to create an e2e ticket for now? -- Alexander Sverdlin Siemens AG www.siemens.com
