From 847135de90abf538866eb30add00dbe6ef037c0c Mon Sep 17 00:00:00 2001 From: Ian Moffett Date: Tue, 22 Jul 2025 11:31:34 -0400 Subject: docs: Add information on SR_STATE.SUPERVISOR Signed-off-by: Ian Moffett --- README.md | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/README.md b/README.md index 83bb7b9..af9ba65 100644 --- a/README.md +++ b/README.md @@ -49,6 +49,12 @@ cannot be accessed via the "mov" instruction and instead rely on independent wrs | 2-31 | Reserved (must be 0) | Must be zero | +#### Supervisor bit +The supervisor bit may only be writable in a privileged mode of execution +and is therefore readonly in user contexts (writes ignored). It may be unset +by system software to transition the processor into a user context. This bit +may only transition from a 0 to a 1 during an interrupt/trap, therefore manually +writing a 1 to this bit is ignored by the processor. ## Instructions -- cgit v1.2.3