On Wed, Feb 12, 2025 at 03:21:46PM -0600, Rob Herring wrote: [...] > > > + - If the kernel is entered at EL1 and EL2 is present: > > > + > > > + - BRBCR_EL2.CC (bit 3) must be initialised to 0b1. > > > + - BRBCR_EL2.MPRED (bit 4) must be initialised to 0b1. > > > > Should clarify BRBCR_EL2.TS to be initialised to 0b00 ? Arm ARM > > claims the reset behaviour of the TS field is unknown value. The > > assembly code below actually has initializes the TS field as zero. > > Humm, we don't currently care what it is initialized to because the > timestamp is never used. We would care in the future if we use > timestamps. Will 0b00 be the only correct value? I'm not sure. In initializaton phase, if set BRBCR_EL2.TS = 0b00, then the timestamp will be decided by BRBCR_EL1.TS. I expect the BRBE driver will always write BRBCR_EL1.TS. Thanks, Leo
