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From: Paul Walmsley <paul@pwsan.com>
To: linux-omap@vger.kernel.org
Cc: Peter de Schrijver <peter.de-schrijver@nokia.com>
Subject: [PATCH 0/3] OMAP3 clock: skip reserved FREQSEL settings
Date: Wed, 12 Nov 2008 11:50:31 -0700	[thread overview]
Message-ID: <20081112183754.31228.73844.stgit@localhost.localdomain> (raw)

Hello,

this series fixes a bug in the OMAP3 DPLL rate rounding code that will
attempt to program the DPLL to use an internal clock frequency that
does not exist in the FREQSEL table in 34xx TRM 4.7.6.2.  This mostly
seems to generate warnings, but can potentially hang the system.

As part of this process, improve the DPLL rate rounding algorithm to
start from a low divider (N) and count up; this should result in fewer
passes through the loop.

Tested on 3430SDP ES2 and a custom ES3 board.  Thanks to Peter de Schrijver
<peter.de-schrijver@nokia.com> for help with these patches.


- Paul

---

   text    data     bss     dec     hex filename
3574155  189440  108880 3872475  3b16db vmlinux.3430sdp.orig
3574251  189440  108880 3872571  3b173b vmlinux.3430sdp

 arch/arm/mach-omap2/clock.c             |  118 ++++++++++++++++++++++++-------
 arch/arm/mach-omap2/clock24xx.h         |    1 
 arch/arm/mach-omap2/clock34xx.h         |    5 +
 arch/arm/plat-omap/include/mach/clock.h |    1 
 4 files changed, 99 insertions(+), 26 deletions(-)


             reply	other threads:[~2008-11-12 18:53 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-11-12 18:50 Paul Walmsley [this message]
2008-11-12 18:50 ` [PATCH 1/3] OMAP3 clock: remove unnecessary dpll_data dereferences Paul Walmsley
2008-11-12 18:51 ` [PATCH 2/3] OMAP3 clock: optimize DPLL rate rounding algorithm Paul Walmsley
2008-11-12 18:52 ` [PATCH 3/3] OMAP3 clock: avoid invalid FREQSEL values during DPLL rate rounding Paul Walmsley
2008-11-21 22:27 ` [PATCH 0/3] OMAP3 clock: skip reserved FREQSEL settings Tony Lindgren

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