Hello,
I don't know whether this question has been asked or not. If yes please direct me to the appropriate discussion.
My question is:
1. Suppose there are two masters, M0, M1 and one slave, S0. M0 initiates an Exclusive access to S0 and gets the response as EXOKAY. M1 initiates a normal access to S0 for the same address as M0. As far as my understanding goes M1 will receive a response as OKAY, is it correct? If no does M0 looses its exclusivity?. Under what circumstances will M0 loose its exclusive access.? Is it when M1 initiates an exclusive access to the same address as M0 or to a different address.(Assuming slave is capable to monitor only 1 address during an exclusive access)
2. How different is Exclusive access as compared to Normal Access. I know that Exclusive Access mainly helps with semaphore type operations. Please provide me with an detailed explanation as to how exactly this happens?
3. When a master initiates a locked access, the entire slave is dedicated to that master (AXI3). From the AXI3 specs, Locked Access can allow only 2 transactions. Is it one locked and next one unlocked? If yes than what purpose does this serve with respect to processor. ? I am trying to understand the locked access behavior.
Thank you very much Mr Martin,
That made so much sense.
So from this understanding there was one query which I was unable to understand.
> From the AXI specs A7.3 it says "Limit locked transaction sequences to two transactions." What does this mean? A locked followed by an unlocking transactions or am I assuming it wrong? Is it restricted to the same address?