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From: Guenter Roeck <linux@roeck-us.net>
To: Zev Weiss <zev@bewilderbeest.net>,
	linux-i2c@vger.kernel.org, Peter Rosin <peda@axentia.se>,
	Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org, openbmc@lists.ozlabs.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 0/2] ic2: mux: pca9541: add delayed-release support
Date: Mon, 28 Feb 2022 05:57:27 -0800	[thread overview]
Message-ID: <fbb305e3-73b3-7a2d-99cf-a7205b7344ff@roeck-us.net> (raw)
In-Reply-To: <YhyLIRFbs226KTwA@hatter.bewilderbeest.net>

On 2/28/22 00:43, Zev Weiss wrote:
> On Mon, Jan 31, 2022 at 04:18:08PM PST, Zev Weiss wrote:
>> Hello,
>>
>> This series adds support for a new pca9541 device-tree property
>> ("release-delay-us"), which delays releasing ownership of the bus
>> after a transaction for a configurable duration, anticipating that
>> another transaction may follow shortly.  By avoiding a
>> release/reacquisition between transactions, this can provide a
>> substantial performance improvement for back-to-back operations -- on
>> a Delta AHE-50DC (ASPEED AST1250) system running OpenBMC with dozens
>> of LM25066 PMICs on PCA9541-arbitrated busses, a setting of 10000 (10
>> ms) reduces the median latency the psusensor daemon's hwmon sysfs file
>> reads from 2.28 ms to 0.99 ms (a 57% improvement).
>>
> 
> Ping...Guenter, any thoughts on this?
> 

It sounds reasonable to me, but I don't have access to hardware anymore
to test it, so I have no means to confirm that it actually works.

Guenter


  reply	other threads:[~2022-02-28 13:58 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-02-01  0:18 [PATCH v2 0/2] ic2: mux: pca9541: add delayed-release support Zev Weiss
2022-02-01  0:18 ` [PATCH v2 1/2] i2c: " Zev Weiss
2022-02-01  0:18 ` [PATCH v2 2/2] dt-bindings: i2c: add nxp, pca9541 release-delay-us property Zev Weiss
2022-02-09 21:47   ` [PATCH v2 2/2] dt-bindings: i2c: add nxp,pca9541 " Rob Herring
2022-02-28  8:43 ` [PATCH v2 0/2] ic2: mux: pca9541: add delayed-release support Zev Weiss
2022-02-28 13:57   ` Guenter Roeck [this message]
2022-02-28 17:11     ` Zev Weiss
2022-02-28 17:19       ` Wolfram Sang
2022-02-28 18:10       ` Guenter Roeck
2022-02-28 21:54 ` Peter Rosin
2022-02-28 22:38   ` Zev Weiss
2022-03-02 14:43     ` Peter Rosin
2022-03-03  0:43       ` Zev Weiss
2022-03-18 11:00         ` Wolfram Sang
2022-03-21 22:32           ` Zev Weiss

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