Re: [PATCH v7 4/9] acpi/arm64: Add GTDT table parse driver

From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: Fu Wei <fu.wei@linaro.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>,
	Len Brown <lenb@kernel.org>,
	Daniel Lezcano <daniel.lezcano@linaro.org>,
	Thomas Gleixner <tglx@linutronix.de>,
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	Sudeep Holla <sudeep.holla@arm.com>,
	Hanjun Guo <hanjun.guo@linaro.org>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>,
	"linaro-acpi@lists.linaro.org" <linaro-acpi@lists.linaro.org>,
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	Christoffer Dall <christoffer.dall@linaro.org>,
	Julien Grall <julien.grall@arm.com>
Subject: Re: [PATCH v7 4/9] acpi/arm64: Add GTDT table parse driver
Date: Fri, 15 Jul 2016 15:07:08 +0200	[thread overview]
Message-ID: <5101961.eCg7ixLQWc@vostro.rjw.lan> (raw)
In-Reply-To: <1809117.TV1VJp2Xpr@vostro.rjw.lan>

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.

Thanks,
Rafael