Message-ID: <bae874f1-7f1f-d6e4-47f7-19d90bdb26af@gmail.com>
Date:   Mon, 23 Jan 2023 11:21:28 -0800
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Subject: Re: [PATCH 3/6] rtc: brcmstb-waketimer: compensate for lack of wktmr
 disable
Content-Language: en-US
To:     Doug Berger <opendmb@gmail.com>,
        Alessandro Zummo <a.zummo@towertech.it>,
        Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc:     Brian Norris <computersforpeace@gmail.com>,
        Markus Mayer <mmayer@broadcom.com>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Broadcom internal kernel review list 
        <bcm-kernel-feedback-list@broadcom.com>, linux-rtc@vger.kernel.org,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org
References: <20230120190147.718976-1-opendmb@gmail.com>
 <20230120190147.718976-4-opendmb@gmail.com>
From:   Florian Fainelli <f.fainelli@gmail.com>
In-Reply-To: <20230120190147.718976-4-opendmb@gmail.com>
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On 1/20/23 11:01, Doug Berger wrote:
> Since the WKTMR hardware block cannot be disabled it is necessary
> for the driver to accommodate for associated timing hazards. This
> commit targets the following possibilities:
> 
> A possible race between clearing a wktmr event and the alarm expiring
> is made one-sided by setting the alarm to its maximum value before
> clearing the event.
> 
> Programming alarm values close to the current time may not trigger
> events if the counter advances while the alarm is being programmed.
> After programming an alarm, a check is made to ensure that it is
> either in the future or an expiration event is pending.
> 
> Signed-off-by: Doug Berger <opendmb@gmail.com>

Acked-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian