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Does ordered-memory-access wait for response?

Hi,

I use Cortex-A17.

Any question.

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Example.1

memory-type is device.

1. LDR R0, [R2]

2. STR R3, [R4]  (R2 != R4)

On AXI-bus, (2.)write transaction is wait for (1.)read response?

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Example.2

memory-type is normal(noncache)

1. LDR R0, [R2]

2. DMB

3. STR R3, [R4]  (R2 != R4)

On AXI-bus, (3.)write transaction is wait for (1.)read response?

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Example.3

memory-type is device or normal(nocache).

1. STR R0, [R2]

    (DMB) for normal memory

2. STR R3, [R4]  (R2 != R4)

On AXI-bus, (2.)write transaction is wait for (1.)write response?

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Parents
  • additional.

    -----------------------------------------------

    On device type memory,

    1.LDR R0,[R2]

    2.LDR R1,[R3]

    or

    1.STR R0, [R2]

    2. STR R1,[R3]

    On AXI bus, Does (2.) wait for (1.)-response(RRESP or BRESP)?

    or

    (1.) and (2.) is same ID. but not wait for response?

    -----------------------------------------------

    On normal noncache type memory,

    1.LDR R0,[R2]

       DMB

    2.LDR R1,[R3]

    or

    1.STR R0, [R2]

       DMB

    2. STR R1,[R3]

    Is it so, too?

Reply
  • additional.

    -----------------------------------------------

    On device type memory,

    1.LDR R0,[R2]

    2.LDR R1,[R3]

    or

    1.STR R0, [R2]

    2. STR R1,[R3]

    On AXI bus, Does (2.) wait for (1.)-response(RRESP or BRESP)?

    or

    (1.) and (2.) is same ID. but not wait for response?

    -----------------------------------------------

    On normal noncache type memory,

    1.LDR R0,[R2]

       DMB

    2.LDR R1,[R3]

    or

    1.STR R0, [R2]

       DMB

    2. STR R1,[R3]

    Is it so, too?

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