[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CAOMZO5CTaqzs2bwXL4V9boMSjOw6TcGBLXe9U=9-wEvwfvGYeQ@mail.gmail.com>
Date: Fri, 30 Jan 2015 17:28:32 -0200
From: Fabio Estevam <festevam@...il.com>
To: Stefan Wahren <stefan.wahren@...e.com>
Cc: Mike Turquette <mturquette@...aro.org>,
Marek Vasut <marex@...x.de>, Zhi Li <lznuaa@...il.com>,
Sascha Hauer <kernel@...gutronix.de>, harald@...ib.org,
Shawn Guo <shawn.guo@...aro.org>,
linux-kernel <linux-kernel@...r.kernel.org>,
"linux-arm-kernel@...ts.infradead.org"
<linux-arm-kernel@...ts.infradead.org>
Subject: Re: [PATCH V2 RESEND] clk: mxs: Fix invalid 32-bit access to frac registers
On Fri, Jan 30, 2015 at 5:20 PM, Stefan Wahren <stefan.wahren@...e.com> wrote:
> According to i.MX23 and i.MX28 reference manual [1],[2] the fractional
> clock control register is 32-bit wide, but is separated in 4 parts.
> So write instructions must not apply to more than 1 part at once.
>
> The clk init for the i.MX28 violates this restriction and all the other
> accesses on that register suggest that there isn't such a restriction.
>
> This patch restricts the access to this register to byte instructions and
> extends the comment in the init functions.
>
> Btw the imx23 init now uses a R-M-W sequence just like imx28 init
> to avoid any clock glitches.
>
> The changes has been tested with a i.MX23 and a i.MX28 board.
>
> [1] - http://cache.freescale.com/files/dsp/doc/ref_manual/IMX23RM.pdf
> [2] - http://cache.freescale.com/files/dsp/doc/ref_manual/MCIMX28RM.pdf
>
> Signed-off-by: Stefan Wahren <stefan.wahren@...e.com>
> Reviewed-by: Marek Vasut <marex@...x.de>
Reviewed-by: Fabio Estevam <fabio.estevam@...escale.com>
Thanks
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists