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Date:   Thu, 06 Oct 2022 09:42:57 +1030
From:   "Andrew Jeffery" <andrew@aj.id.au>
To:     openipmi-developer@lists.sourceforge.net,
        "Corey Minyard" <minyard@acm.org>
Cc:     linux-aspeed@lists.ozlabs.org, openbmc@lists.ozlabs.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH] ipmi: kcs: Poll OBF briefly to reduce OBE latency
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Hi Corey,

On Sat, 13 Aug 2022, at 00:17, Andrew Jeffery wrote:
> The ASPEED KCS devices don't provide a BMC-side interrupt for the host
> reading the output data register (ODR). The act of the host reading ODR
> clears the output buffer full (OBF) flag in the status register (STR),
> informing the BMC it can transmit a subsequent byte.
>
> On the BMC side the KCS client must enable the OBE event *and* perform a
> subsequent read of STR anyway to avoid races - the polling provides a
> window for the host to read ODR if data was freshly written while
> minimising BMC-side latency.

Just wondering whether you're happy to pick this one up? I haven't seen 
it hit the IPMI tree yet.

Cheers,

Andrew