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    AMBA AXI AxLOCK brief

    What is the difference between LOCKED access and Exclusive access in AXI,

    i read some articles in web and arm discussion forum also. But still failed to understood.
    Can any one please brief about it.

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    Re: AMBA AXI AxLOCK brief

    Exclusive allows a master to finish a semaphore type access at a later time using the id mechanism and the slave either accepts the subsequent transaction or rejects it if another master accessed the same location. This is done in the slave logic.

    Locked disallows any other master access to a slave until the master completes the locked transactions. This requires that the interconnect fabric and arbiter enforce this.

    AXI4 dropped locked transactions, due to lack of needing it, the added complexity to the interconnect and arbiter, and the impact on QoS.

    Don't know why you relied on the discussion forum or web articles, the AMBA spec is pretty clear on what the differences are and even gives rudimentary examples. If you sign up on the ARM website you can download the specs for free.


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