Re: [PATCH v2 6/7] Watchdog: introduce ARM SBSA watchdog driver

From: Fu Wei
Date: Sat May 23 2015 - 15:28:37 EST


Hi Timur,



On 23 May 2015 at 23:08, Timur Tabi <timur@xxxxxxxxxxxxxx> wrote:
> Arnd Bergmann wrote:
>>
>> I think it's a reasonable assumption that someone will sooner or later
>> put that hardware into an ARM32 machine,
>
>
> I'm going to have to disagree. If they haven't done it by now, I can't
> imagine any ARM SOC vendor creating a 32-bit ARM SOC with an SBSA watchdog
> in it. I can imagine a vendor trying to repurpose an existing 32-bit ARM
> SOC for the server market, but that SOC won't have an SBSA watchdog in it.

I will agree with you on this, ONLY IF a people can represent ARM and
all chip vendors say publicly:
" We never ever use SBSA watchdog IP core on ARM32!" or " SBSA
watchdog IP core is imcompatible with ARM32"

Although the SBSA is all about ARMv8, but in "5 APPENDIX A: GENERIC
WATCHDOG", it doesn't say "this is only for ARMv8".
and its clock source "system counter" and arm_arch_timer have been in
ARM32 Soc for years,
and all the regs in SBSA watchdog is 32bit. I can't see why we can not
do that, unless I miss something.

I wonder why you are so sure "that SOC won't have an SBSA watchdog in
it." any documentation ?
Sorry, I am not a chip design engineer, I can't see why 32-bit ARM
won't have an SBSA watchdog in it.

>
>> or run a 32-bit kernel on
>>
>> a chip that has it.
>
>
> That might happen, but I would be very surprised, and I would need to be
> convinced that it's useful.
>
> --
> 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,
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Shanghai,China 200021
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