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From: Boris Brezillon <>
To: Sekhar Nori <>
Cc: David Lechner <>,
	Bartosz Golaszewski <>,
	Richard Weinberger <>,, Marek Vasut <>,,
	Cyrille Pitchen <>,
	Brian Norris <>,
	David Woodhouse <>,
	Linux ARM Mailing List <>
Subject: Re: [PATCH] mtd: nand: davinci: don't acquire and enable clock
Date: Mon, 2 Apr 2018 09:01:00 +0200	[thread overview]
Message-ID: <20180402090100.28961677@bbrezillon> (raw)
In-Reply-To: <>

On Fri, 30 Mar 2018 20:00:51 +0530
Sekhar Nori <> wrote:

> NAND itself is an asynchronous interface, it does not have any
> clock input. DaVinci NAND driver acquires clock for AEMIF
> (asynchronous external memory interface) which is an on-chip
> IP to which NAND is connected.
> The same clock is also enabled in AEMIF driver (either present
> drivers/memory or from machine code for some older platforms).
> AEMIF timing must be initialized before NAND can be accessed.
> This ensures that AEMIF clock is enabled too.
> Remove the superfluous clock acquisition and enable in DaVinci
> NAND driver.
> Tested on K2L, K2HK, K2E, DA850 EVM, DA850 LCDK in device-tree
> boot and DM644x EVM in legacy boot.
> Signed-off-by: Sekhar Nori <>
> ---
> Hi Boris,
> If/when this patch gets accepted,

I'll probably queue it just after v4.17-rc1 is out if nobody complains
about the change.

> it will nice to put this on
> an immutable branch others can merge. There is potential cleanup
> in drivers/clock and in DaVinci machine code that will depend
> on this.

Sure, I can do that. 

Boris Brezillon, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering

  reply	other threads:[~2018-04-02  7:01 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-03-30 14:30 Sekhar Nori
2018-04-02  7:01 ` Boris Brezillon [this message]
2018-04-02  7:03 ` Boris Brezillon
2018-04-25  8:53 ` Bartosz Golaszewski
2018-04-26 18:01 ` Boris Brezillon

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