Hi, Am Freitag, 30. August 2024, 10:53:16 CEST schrieb Carlos Song: > > -----Original Message----- > > From: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxx> > > Sent: Thursday, August 29, 2024 6:55 PM > > To: Aisheng Dong <aisheng.dong@xxxxxxx>; andi.shyti@xxxxxxxxxx; > > shawnguo@xxxxxxxxxx; s.hauer@xxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx; > > festevam@xxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > > Cc: linux-i2c@xxxxxxxxxxxxxxx; imx@xxxxxxxxxxxxxxx; > > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Carlos Song > > <carlos.song@xxxxxxx> > > Subject: [EXT] Re: [PATCH 5/5] i2c: imx-lpi2c: increase PM timeout to avoid > > operate clk frequently > > > > Caution: This is an external email. Please take care when clicking links or > > opening attachments. When in doubt, report the message using the 'Report this > > email' button > > > > > > Hi, > > > > Am Donnerstag, 29. August 2024, 11:37:22 CEST schrieb carlos.song@xxxxxxx: > > > From: Clark Wang <xiaoning.wang@xxxxxxx> > > > > > > Switching the clock frequently will affect the data transmission > > > efficiency, and prolong the timeout to reduce autosuspend times for > > > lpi2c. > > > > Efficiency as in throughput or total time per transfer? Do you have any numbers? > > > > Hi, Thank your for your quick ack! > > Apologies for the unclear explanation. The efficiency I'm referring to isn't just for I2C. For platforms with SC firmware > like the 8X series, every i2c transfer to enable or disable the clock notifies the SC firmware to perform a clock operation. > So if the autosuspend time is short, i2c may enable and disable clock frequently, it will occupy resources of the SC firmware. > > Therefore, we add this patch to minimize the excessive sc firmware resource waste caused by frequent I2C clock enable/disable operations. Thanks for the explanation. So this delay only occurs on systems using an SC (imx8qm/qxp) or SM (imx95), right? Is there a chance to detect this kind of clock provider and make this timeout configurable? Best regards, Alexander -- TQ-Systems GmbH | Mühlstraße 2, Gut Delling | 82229 Seefeld, Germany Amtsgericht München, HRB 105018 Geschäftsführer: Detlef Schneider, Rüdiger Stahl, Stefan Schneider http://www.tq-group.com/
