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From: Fu Wei <fu.wei@linaro.org>
Date: Sat, 16 Jul 2016 00:32:14 +0800
Message-ID: <CADyBb7sXxY_a+tJQoH01eUk5-xvg9jRZtzyhB-tDstWoBAWfLg@mail.gmail.com>
Subject: Re: [PATCH v7 4/9] acpi/arm64: Add GTDT table parse driver
To: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>, Len Brown <lenb@kernel.org>,
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Hi Rafael,

On 15 July 2016 at 21:07, Rafael J. Wysocki <rjw@rjwysocki.net> wrote:
> On Friday, July 15, 2016 02:15:27 PM Rafael J. Wysocki wrote:
>> On Friday, July 15, 2016 03:32:35 PM Fu Wei wrote:
>> > Hi Rafael,
>> >
>
> [cut]
>
>> > >
>> > >> +               return 0;
>> > >> +       }
>> > >> +
>> > >> +       if (!gtdt->platform_timer_count) {
>> > >> +               pr_info("No Platform Timer.\n");
>> > >> +               return 0;
>> > >> +       }
>> > >> +
>> > >> +       acpi_gtdt_desc.platform_timer_start = (void *)gtdt +
>> > >> +                                             gtdt->platform_timer_offset;
>> > >> +       if (acpi_gtdt_desc.platform_timer_start <
>> > >> +           (void *)table + sizeof(struct acpi_table_gtdt)) {
>> > >> +               pr_err(FW_BUG "Platform Timer pointer error.\n");
>> > >
>> > > Why pr_err()?
>> >
>> > if (true), that means the GTDT table has bugs.
>> >
>>
>> And that's not a very useful piece of information unless you're debugging the
>> platform, is it?
>
> FWIW, I'm not a big fan of printing "your firmware is buggy" type of messages
> (especially at the "error" log level or higher) unless they can be clearly
> connected to a specific type of functional failure.
>
> So if you want to pring an error-level message, something like "I cannot do X
> because of the firmware bug Y" would be better IMO.

So can I do this:
pr_err(FW_BUG "Can NOT init platform_timer pointer, because of the
GTDT table bug\n");

or pr_debug(FW_BUG "Can NOT init platform_timer_start, because of
platform_timer_offset bug in GTDT\n");

or just delete it?

which one do you prefer?  I think maybe should provide some clue for
users to fix the problem  :-)

any thought ?


>
> Thanks,
> Rafael
>



-- 
Best regards,

Fu Wei
Software Engineer
Red Hat