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From: "João Paulo Silva Gonçalves" <joao.goncalves@toradex.com>
To: "nm@ti.com" <nm@ti.com>, "faiz_abbas@ti.com" <faiz_abbas@ti.com>,
	"ulf.hansson@linaro.org" <ulf.hansson@linaro.org>,
	"linux-mmc@vger.kernel.org" <linux-mmc@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Cc: "adrian.hunter@intel.com" <adrian.hunter@intel.com>,
	Francesco Dolcini <francesco.dolcini@toradex.com>
Subject: SDHCI AM654 driver delaying boot time
Date: Wed, 8 Nov 2023 18:56:19 +0000	[thread overview]
Message-ID: <0e81af80de3d55e72f79af83fa5db87f5c9938f8.camel@toradex.com> (raw)

Hello all, 

We are trying to minimize boot time for our AM62 devices. Unfortunately, we have identified a delay of approximately 1.5 seconds caused by the
sdhci_am654 driver. This delay is a result of a timeout within the driver (MAX_POWER_ON_TIMEOUT) and was introduced in commit 7ca0f16 ("mmc:
sdhci_am654: Add workaround for card detect debounce timer"). This issue arises only when there is no SD card present in the MMC slot.  We tested the
driver with a lower timeout value and everything worked. However, as indicated in the commit message, this timeout may be related to the way the sdhci
controller hardware IP works. Currently, the driver employs a sort of a "busy loop" to wait for this timeout to pass delaying the boot. Why is
need to busy loop for this timeout? Is it possible to wait for it in the backgroud? Am I am missing something here? 

Regards,
Joao Paulo


             reply	other threads:[~2023-11-08 18:57 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-11-08 18:56 João Paulo Silva Gonçalves [this message]
2023-11-09 17:51 ` SDHCI AM654 driver delaying boot time Nishanth Menon
2023-11-10  4:38   ` Vignesh Raghavendra
2023-11-10 14:55     ` João Paulo Silva Gonçalves
2023-11-10 14:19   ` Francesco Dolcini
2023-11-14  8:25     ` Adrian Hunter

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