[PATCH V5 0/6] ARM: OMAP3+: support cpufreq-cpu0 for device tree boot

From: Nishanth Menon
Date: Wed May 08 2013 - 15:08:33 EST


The following version 5 of the series arose from trying to use
BeagleBoard-XM (OMAP3 variant) for doing CPU DVFS using cpufreq-cpu0.
This series enables the generic cpufreq-cpu0 driver to be used in
device tree enabled boot while maintaining support of the legacy
omap-cpufreq driver when used in non device tree enabled boot.

However, in order to enable complete SoC entitlement for OMAP
platforms, with this series, key features are still pending on device
tree adaptation for OMAP:
A) clock framework data transition to DT - this series provides an
driver to allow device tree definition of clock node.
B) On processors that use voltage controller, voltage processor
(VC/VP hardware loop using I2C_SR path) - we have started work on
transitioning them to regulator framework driven by DT.
C) Adaptive Body Bias[2] and SmartReflex AVS conversion to DT.

Note: Common Clock Framework(CCF) could also control regulators[3] and
AVS to ensure proper sequencing required for full DVFS sequencing.
Once these conversions are complete, there might be minimal cleanup
work to switch to the new data structure changes.

Key benefit of the series is to allow all relevant TI platforms now to
use a single cpufreq driver and equivalent frameworks in addition be
part of the transition to device tree.

NOTE on this series:
1. omap-cpufreq will be used only in non device tree boot scenario. we
should delete this driver once the 100% DT conversion is complete.
2. Generic cpufreq-cpu0 will be used only in device tree boot scenario
boot systems
3. clock data movement as approached by Tero in [4] is not the
objective of this series
4. meant for post 3.10-rc1 tag

Key changes in version 5 since version 4:
- rebase with master for 3.10-rc1 intermediate
- review comments incorporated

version 4 of the series:
http://marc.info/?l=linux-arm-kernel&m=136580742724210&w=2
available at:
https://github.com/nmenon/linux-2.6-playground/commits/push/cpufreq-cpu0-omap-all-v4

version 3 of the series:
http://marc.info/?l=linux-pm&m=136450759315742&w=2
available at:
https://github.com/nmenon/linux-2.6-playground/commits/push/cpufreq-cpu0-omap-all-v3

version 2 of the series:
http://marc.info/?t=136371570200003&r=1&w=2
available at:
https://github.com/nmenon/linux-2.6-playground/commits/push/cpufreq-cpu0-omap-all-v2

version 1 of the series:
http://marc.info/?t=136329485400005&r=1&w=2
available at:
https://github.com/nmenon/linux-2.6-playground/commits/push/cpufreq-cpu0-omap-all-v1

[1] Original discussion thread which triggered this series:
http://marc.info/?l=linux-pm&m=136304313700602&w=2
https://patchwork.kernel.org/patch/2251841/
https://patchwork.kernel.org/patch/2251851/
[2] ABB series: http://marc.info/?l=linux-omap&m=136751559523901&w=2 (ABB DTS merge pending)
[3] CCF DVFS patches:
https://patchwork.kernel.org/patch/2195431/
https://patchwork.kernel.org/patch/2195421/
https://patchwork.kernel.org/patch/2195451/
https://patchwork.kernel.org/patch/2195441/
https://patchwork.kernel.org/patch/2195461/
[4] http://marc.info/?t=136388745000001&r=1&w=2

Version 5 is now based on master since all requisite for-next branches have been merged.
master 5af43c2 Merge branch 'akpm' (incoming from Andrew)

Version 4 is also available at:
https://github.com/nmenon/linux-2.6-playground/commits/push/cpufreq-cpu0-omap-all-v5
git link: git://github.com/nmenon/linux-2.6-playground.git
branch: cpufreq-cpu0-omap-all-v5

Test coverage:
test script: http://pastebin.com/GsavxiDe
(note - to allow testing, I followed the suggestion in https://lkml.org/lkml/2013/5/8/19 )

Platforms verified:
beaglebone(rev A6a) - AM33xx compatible - http://pastebin.com/zANKsYBp
beagleboard (rev C1D) - OMAP3430 compatible
- DT enabled boot: http://pastebin.com/q4qZYVaK
- No DT enabled boot: http://pastebin.com/c1CbQmV5
omap3-beagle-xm -OMAP3630 compatible - http://pastebin.com/ibUABcA0
SDP4430 -(OMAP4430 ES2.2) - http://pastebin.com/wYwUc3fU
Pandaboard-ES -(OMAP4460 ES1.1) - http://pastebin.com/FB2RiFp2

Nishanth Menon (6):
clk: OMAP: introduce device tree binding to kernel clock data
[Clk driver probably belongs to mike's tree?]
ARM: dts: OMAP3: add clock nodes for CPU
ARM: dts: OMAP4: add clock nodes for CPU
ARM: dts: AM33XX: add clock nodes for CPU
[The above probably belong to Benoit's tree]
ARM: OMAP2+: AM33XX: add lateinit hook for calling pm late init
ARM: OMAP3+: use cpu0-cpufreq driver in device tree supported boot
[The above probably belong to Kevin/Tony's tree]

.../devicetree/bindings/clock/omap-clock.txt | 40 +++++++++
arch/arm/boot/dts/am33xx.dtsi | 7 ++
arch/arm/boot/dts/omap3.dtsi | 7 ++
arch/arm/boot/dts/omap4.dtsi | 7 ++
arch/arm/mach-omap2/board-generic.c | 1 +
arch/arm/mach-omap2/cclock33xx_data.c | 1 -
arch/arm/mach-omap2/common.h | 1 +
arch/arm/mach-omap2/io.c | 6 ++
arch/arm/mach-omap2/pm.c | 11 ++-
drivers/clk/Makefile | 1 +
drivers/clk/omap/Makefile | 1 +
drivers/clk/omap/clk.c | 91 ++++++++++++++++++++
12 files changed, 170 insertions(+), 4 deletions(-)
create mode 100644 Documentation/devicetree/bindings/clock/omap-clock.txt
create mode 100644 drivers/clk/omap/Makefile
create mode 100644 drivers/clk/omap/clk.c

Regards,
Nishanth Menon
--
1.7.9.5

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