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From: Tomi Valkeinen <tomi.valkeinen@ti.com>
To: Paul Walmsley <paul@pwsan.com>, linux-omap <linux-omap@vger.kernel.org>
Cc: Jon Hunter <jon-hunter@ti.com>
Subject: Bad divider used for sysclk for DSS and ABE (CM_ABE_DSS_SYS_CLKSEL)
Date: Wed, 6 Feb 2013 13:33:24 +0200	[thread overview]
Message-ID: <51123F84.3040101@ti.com> (raw)

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Hi Paul,

OMAP4 TRM has a mention in CM_ABE_DSS_SYS_CLKSEL's description:

"Select SYS_CLK divided by 2. Must be used for
SYS_CLK > 26 MHz"

This doesn't seem to be enforced with the current kernel. OMAP4 blaze
has 38.4MHz sys clk, but above mentioned divider is 1.

I made a quick test with omapdss, so that omapdss sets the divider to 2
when initializing. Everything seemed to work fine, although everything
has been working fine with the divider 1 also. But I think it'd be wise
to adhere to the TRM.

Is this something that the bootloader should setup, or should kernel do
it (also)?

 Tomi


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                 reply	other threads:[~2013-02-06 11:33 UTC|newest]

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