Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Fri, 5 Oct 2018 00:14:32 +0800
From:   Guo Ren <ren_guo@c-sky.com>
To:     Daniel Lezcano <daniel.lezcano@linaro.org>
Cc:     tglx@linutronix.de, jason@lakedaemon.net, marc.zyngier@arm.com,
        robh+dt@kernel.org, mark.rutland@arm.com, anurup.m@huawei.com,
        Jonathan.Cameron@huawei.com, will.deacon@arm.com,
        zhangshaokun@hisilicon.com, jhogan@kernel.org,
        paul.burton@mips.com, peterz@infradead.org, f.fainelli@gmail.com,
        arnd@arndb.de, linux-kernel@vger.kernel.org,
        devicetree@vger.kernel.org
Subject: Re: [PATCH V9 3/8] clocksource: add C-SKY SMP timer
Message-ID: <20181004161431.GA30844@guoren-Inspiron-7460>
References: <cover.1538355281.git.ren_guo@c-sky.com>
 <eee964dd57d12bc630280ab84235b5356799b1fb.1538355281.git.ren_guo@c-sky.com>
 <88e320f2-8cf0-fdb9-c9b0-ee25d7a4d00f@linaro.org>
 <20181002054024.GA12645@guoren>
 <49238cda-d12c-7d3f-9333-296527d94f12@linaro.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <49238cda-d12c-7d3f-9333-296527d94f12@linaro.org>
User-Agent: Mutt/1.5.24 (2015-08-30)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Tue, Oct 02, 2018 at 09:59:42AM +0200, Daniel Lezcano wrote:
> On 02/10/2018 07:40, Guo Ren wrote:
> [ ... ]
> 
> >>
> >> 	irq = irq_of_parse_and_map(np, 0);
> >> 	if (irq <= 0)
> >> 		return -EINVAL;
> > 		panic();
> > I want a panic here. Return will make debug confused and directly tell
> > the people where is wrong. It's root-timer for us and it must bootup.
> > 
> > If it's a co-timer, I also think return is good.
> 
> We don't need a panic in case of failure. If the board as an alternate
> timer it should be able to boot, that is the general rule of thumb for
> these drivers in this directory.
> 
> The init timer functions will be called via the timer_probe() which
> browse the timer_of_table (the one with all entries for the
> TIMER_OF_DECLARE macros).
> 
> You can see in the code below (from timer_probe.c), there is an error
> message emitted if the driver fails to initialize and another one much
> stronger if no timer was initialize.
> 
> This is enough trace IMO.
> 
> void __init timer_probe(void)
> {
>         struct device_node *np;
>         const struct of_device_id *match;
>         of_init_fn_1_ret init_func_ret;
>         unsigned timers = 0;
>         int ret;
> 
>         for_each_matching_node_and_match(np, __timer_of_table, &match) {
>                 if (!of_device_is_available(np))
>                         continue;
> 
>                 init_func_ret = match->data;
> 
>                 ret = init_func_ret(np);
>                 if (ret) {
>                         pr_err("Failed to initialize '%pOF': %d\n", np,
> ret);
>                         continue;
>                 }
> 
>                 timers++;
Ok, let other timers boot up as possible and no panic for csky timer.

 Guo Ren