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    SubjectRe: [PATCH v2 0/7] Add support for Exynos SROM Controller driver
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    On 05.10.2015 22:18, Pavel Fedin wrote:
    > Hello!
    >
    >> That is interesting. What do you mean by that? Although SROM controller
    >> can access external memory (SRAM, ROM) but it is not exactly a bus. How
    >> is the SMSC9111 "connected"? What interface or protocol is used?
    >
    > SROM controller actually provides a demultiplexed external address and data bus. This way you could
    > hook up old good ROM chip to it (hence its name). However, you can plug in there anything else with
    > the appropriate interface, and SMSC9111 uses exactly that. Just some address + control + data wires.
    > Therefore, you can think of SROMc as a simple bus.

    Ah, okay, thanks for details.

    >
    >> I am sorry but I cannot figure out what exactly are you talking about.
    >> The Device Tree is the glue to describe the board, the hardware and its
    >> configuration. Please elaborate a little more.
    >
    > Yes, exactly that. SROM controller has 4 outputs, and for every of these outputs you have to choose
    > mode and timings. Once you set them correctly, you can use peripherial behind them. These timings
    > actually depend on the actual peripherial.
    >
    > By this time i remembered that u-boot guys also did something with this. And here are links:
    > http://git.denx.de/?p=u-boot.git;a=blob;f=arch/arm/dts/exynos5250-smdk5250.dts;h=8b695442b1a29dec4e3
    > 53ebd3cfee0ff89f218a6;hb=HEAD#l43 - this is how connection is described
    > http://git.denx.de/?p=u-boot.git;a=blob;f=board/samsung/common/board.c;h=d32c75de50858f131284e28db0c
    > 7ed55883f1cb0;hb=HEAD#l184 - and this is parsing code

    I see... Pankaj's driver was not developed for that purpose. You would
    have to extend it. For the SROMC driver there shouldn't be much work to
    do: just parse additional bindings and configure the controller for
    ethernet adapter.

    > There's only one small problem with their code. "bank" parameter is device-wide, therefore you
    > cannot configure more than one bank. For SMDK boards it's OK, but in future you may run into problem
    > with this.

    You are not bound by u-boot bindings anyhow (at least to my
    understanding). You can try to re-use them but if some binding is
    problematic then just create your own.

    Best regards,
    Krzysztof



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