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    SubjectRe: [Linaro-acpi] [PATCH v8 5/5] Watchdog: introduce ARM SBSA watchdog driver
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    Hi Timur,

    On 5 November 2015 at 22:08, Timur Tabi <timur@codeaurora.org> wrote:
    > Fu Wei wrote:
    >>
    >> SBSA 2.3 Page 23 :
    >> Note: the watchdog offset register is 32 bits wide. This gives a
    >> maximum watch period of around 10s at a system
    >> counter frequency of 400MHz. If a larger watch period is required then
    >> the compare value can be programmed
    >> directly into the compare value register.
    >>
    >> 214s means your system counter is approximately at 20MHz which is in
    >> the range of (10MHz ~ 400MHz)
    >>
    >> SBSA 2.3 Page 13 :
    >> The System Counter (of the Generic Timer) shall run at a minimum
    >> frequency of 10MHz and maximum of
    >> 400MHz.
    >
    >
    > Thanks, that explains a lot.
    >
    > If we expected customers to have a lower system counter frequency, then we
    > wouldn't have to worry about the timeouts being too short. It seems to me
    > that the SBSA spec says that if you want a longer timeout, you have to lower
    > the frequency.

    Did you really read the "Note" above???????? OK, let me paste it again
    and again:

    SBSA 2.3 Page 23 :
    If a larger watch period is required then the compare value can be
    programmed directly into the compare value register.

    > We shouldn't be complicating the driver because some
    > customers might not follow the spec.

    OK it this customer might not follow the spec, that watchdog is not a
    SBSA watchdog,
    So please don't use SBSA watchdog driver on that non-SBSA watchdog
    device, Thanks a lot

    >
    >
    > --
    > Sent by an employee of the Qualcomm Innovation Center, Inc.
    > The Qualcomm Innovation Center, Inc. is a member of the
    > Code Aurora Forum, hosted by The Linux Foundation.



    --
    Best regards,

    Fu Wei
    Software Engineer
    Red Hat Software (Beijing) Co.,Ltd.Shanghai Branch
    Ph: +86 21 61221326(direct)
    Ph: +86 186 2020 4684 (mobile)
    Room 1512, Regus One Corporate Avenue,Level 15,
    One Corporate Avenue,222 Hubin Road,Huangpu District,
    Shanghai,China 200021


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