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Project related information in bitfiles

Neelakandan Manihatty Bojan edited this page Jun 8, 2014 · 2 revisions

Register 1:

Used to store the epoch time in hexadecimal. We first obtain the epoch time using the 'date +%s' (shown below) and convert this to hex value.


nm525@nf-test111:~$ date +%s

1400850804


 Byte Number -->    4     3     2     1         
                 +-----+-----+-----+-----+         
                 |                       |
                 |       EPOCH LOWER     |
                 |                       |
                 +-----+-----+-----+-----+

It is well known that a signed 4-byte integer has a maximum value of 2,147,483,647. So this limits us to year 2038. For more accurate value see below.


nm525@nf-test111:~$ date -d @2147483647

Tue Jan 19 03:14:07 GMT 2038


Register 2:

To address the 2038 issue, we add another register to store the upper 32 bits.

 Byte Number -->    4     3     2     1         
                 +-----+-----+-----+-----+         
                 |                       |
                 |     EPOCH UPPER       |
                 |                       |
                 +-----+-----+-----+-----+

Register 3:

Used to store the detail of about the project.

 Byte Number -->    4     3     2     1         
                 +-----+-----+-----+-----+
                 |           |           |
                 |    PF     |   RC/PID  |
                 |           |           |
                 +-----+-----+-----+-----+
                          ǀ     ǀ
                          ǀ     ǀ
                          ǀ      ------------------------------> RC (1 bit) is used to identify if the project is a reference/contrib project. Remaining 15 bits are used to identify the project.
                          -------------------------------------> Byte 3 and 4- Can be used to store the project features
                                           ǀ        ǀ
                                           ǀ        -----------> Byte 3 is used to store the DMA ID.(Encoding pattern is as follows : DMA_V1 OPED (8'd1)/ DMA_V2 MARIO(8'd2)/ DMA_V3 MARCO(8'd3))
                                           ǀ
                                            -------------------> Byte 4 is used to store other features
                                                                     Bit 0 (LSB)  : phy initialization (Encoding pattern is: Initialized by Microblaze(1'b0), requires initialization by driver(1'b1))
                                                                     Bit 1 : register availablity in pipeline (availablity(1'b1), unavailability(1'b0))
                                                                     Bit 2 : test suite availablity (availablity(1'b1), unavailability(1'b0))
                                                                     Bit 3 - Bit 7 : tool flow (ISE(4'd1)/ EDK(4'd2)/ VIVADO(4'd3)/ VIVADO 14.2 (4'd4) etc )

Register 4:

Used to store the release tag of the project.

 Byte Number -->    4     3     2     1
                 +-----+-----+-----+-----+
                 |     |     |     |     |
                 |  RR |  RR | RT  |  RT |
                 |     |     |     |     |
                 +-----+-----+-----+-----+
                    ǀ     ǀ     ǀ     ǀ
                    ǀ     ǀ     ǀ      ------------------------> Byte 1- Used to identify the lower two digits of the release tag
                    ǀ     ǀ      ------------------------------> Byte 2- Used to identify if the upper digits of the release tag
                    ǀ     -------------------------------------> Byte 3- Reserved for future use
                    -------------------------------------------> Byte 4- Reserved for future use

Register 5:

Used to store the board information.

 Byte Number -->    4     3     2     1
                 +-----+-----+-----+-----+
                 |     |     |     |     |
                 |  AN | PCBV| BID | REV |
                 |     |     |     |     |
                 +-----+-----+-----+-----+
                    ǀ     ǀ     ǀ     ǀ
                    ǀ     ǀ     ǀ      ------------------------> Byte 1- Used to identify the Board revision (Revison number of the board can be encoded in binary)
                    ǀ     ǀ      ------------------------------> Byte 2- Used to identify the board (Encoding pattern is as follows : NetFPGA-1G (8'd1)/ NetFPGA-10G(8'd2)/ CML(8'd3)/ SUME(8'd4))
                    ǀ     -------------------------------------> Byte 3- PCB version (not known for NetFPGA-10G)
                    -------------------------------------------> Byte 4- Assembly number (for NetFPGA-10G not know, so currently set to 0)

Register 6 - Register 16:

 Byte Number -->    4     3     2     1
                 +-----+-----+-----+-----+
                 |     |     |     |     |
                 |  RR |  RR | RR  |  RR |
                 |     |     |     |     |
                 +-----+-----+-----+-----+
                    ǀ     ǀ     ǀ     ǀ
                    ǀ     ǀ     ǀ      ------------------------> Byte 1- Reserved for future use
                    ǀ     ǀ      ------------------------------> Byte 2- Reserved for future use
                    ǀ     -------------------------------------> Byte 3- Reserved for future use
                    -------------------------------------------> Byte 4- Reserved for future use
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