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EUnsu's avatar
EUnsu
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5 years ago

What is the highest frequency of the h2f_axi_clk and h2f_lw_axi_clk clocks?

2 Replies

  • Hi,

    May I know first which device you are referring to actually? Cyclone V SoC, Arria 10 SoC etc.

  • EUnsu's avatar
    EUnsu
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    Hello!

    I am sorry. I have forgotten to specify the device, it is Cyclone V SOC, part number is 5CSEBA4U19I7N.

    Now I am using the following configuration:

    1. AXI FPGA-to-HPS bridge clock (h2f_axi_clk) is 200MHz, the data width is 128 bits.

    2. There are baremetal, Intes`s Hwlib and FreeRTOS.

    The device is working properly. The maximum transfer rates (between CPU and FPGA on-chip memory) that I have achieved are:

    When access through a range of virtual addresses with attribute ALT_MMU_ATTR_NC:

    1. CPU write data to FPGA is ~1216 MByte/sec.

    2. CPU read data from FPGA is ~450 MByte/sec.

    When access through a range of virtual addresses with attribute ALT_MMU_ATTR_DEVICE:

    1. CPU write data to FPGA is ~571 MByte/sec.

    2. CPU read data from FPGA is ~406 MByte/sec.

    Data sizes range is 32768 bytes.

    These rates are enough for our application, but I would like to try to increase their without

    using DMA, simply increasing the frequency of h2f_axi_clk.