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Date:   Sun, 23 Jun 2019 18:25:37 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Vadim Pasternak <vadimp@mellanox.com>
Cc:     Ido Schimmel <idosch@idosch.org>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "davem@davemloft.net" <davem@davemloft.net>,
        Jiri Pirko <jiri@mellanox.com>, mlxsw <mlxsw@mellanox.com>,
        Ido Schimmel <idosch@mellanox.com>
Subject: Re: [PATCH net-next 3/3] mlxsw: core: Add support for negative
 temperature readout
Message-ID: <20190623162537.GF28942@lunn.ch>
References: <20190623125645.2663-1-idosch@idosch.org>
 <20190623125645.2663-4-idosch@idosch.org>
 <20190623154407.GE28942@lunn.ch>
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> > Why the > 0?
> 
> We don't consider negative temperature for thermal control.

Is this because the thermal control is also broken and does not
support negative values? This is just a workaround papering over the
cracks?

I've worked on some systems where the thermal subsystem has controller
a heater. Mostly industrial systems, extended temperature range, and
you have to make sure the hardware is kept above -25C, otherwise the
DRAM timing goes to pot and the system crashed and froze.

	Andrew