[PATCH v3 0/3] add the reset controller to the Meson8b clkc

[Martin Blumenstingl]

Hi Neil,

On Mon, Jul 31, 2017 at 1:59 PM, Neil Armstrong <narmstrong at baylibre.com> wrote:
> On 07/31/2017 10:27 AM, Jerome Brunet wrote:
>> On Fri, 2017-07-28 at 23:13 +0200, Martin Blumenstingl wrote:
>>> This registers the known (soft) reset lines provided by the clock
>>> controller's registers.
>>>
>>> This is the first preparation step for SMP and CPU hotplug support on
>>> Meson8/Meson8b/Meson8m2. Booting the secondary cores on these SoCs
>>> requires asserting and de-asserting a reset line (one for each CPU
>>> core). These reset lines are provided by the clock controller.
>>>
>>> The reset controller part of the meson8b clock controller has to be
>>> registered early (which I did through CLK_OF_DECLARE_DRIVER), because
>>> the secondary cores are started *very* early in the boot process (and
>>> meson8b_clkc_probe is invoked long after we need the reset controller
>>> to be available for booting the secondary CPU cores).
>>>
>>> The user of the reset-controller (= the patches which enable SMP and
>>> CPU hotplug support) will follow in the next days. I decided to split
>>> this because the SMP series will probably consist of 6 patches alone
>>> (and may need to go through two separate trees).
>>>
>>> Changes since v2 at [3]:
>>> - move the reset line preprocessor defines into a separate file
>>>   (affects patch #1 as this header file is part of the dt-binding)
>>> - rename the reset line preprocessor macros from RESETID_ to
>>>   CLKC_RESET_ to clearly indicate that these are provided by the
>>>   clock controller (unlike the preprocessor macros for the reset
>>>   lines in the standlone reset controller, which start with RESET_)
>>> - updated patch #2 due to the changes mentioned above
>>> - added Neil's Reviewed-by to all patches
>>>
>>> Changes since v1 at [0]:
>>> - updated cover letter description as we are now registering more than
>>>   four reset lines
>>> - split patch #1 into a dt-binding and clk driver patch
>>> - slightly reworded the dt-binding documentation so it's now clear that
>>>   the reset identifiers are preprocessor macros in
>>>   dt-bindings/clock/meson8b-clkc.h (v1 of this series didn't have these
>>>   macros at all)
>>> - patch #2 (previously part of patch #1) now registers all known reset
>>>   lines (see [1] and [2] for the results of my detective work)
>>> - patch #3 is untouched
>>>
>>>
>>> [0] http://lists.infradead.org/pipermail/linux-amlogic/2017-July/004283.html
>>> [1] http://lists.infradead.org/pipermail/linux-amlogic/2017-July/004330.html
>>> [2] http://lists.infradead.org/pipermail/linux-amlogic/2017-July/004347.html
>>> [3] http://lists.infradead.org/pipermail/linux-amlogic/2017-July/004352.html
>>>
>>>
>>> Martin Blumenstingl (3):
>>>   dt-bindings: clock: meson8b: describe the embedded reset controller
>>>   clk: meson: meson8b: register the built-in reset controller
>>>   ARM: dts: meson: mark the clock controller also as reset controller
>>>
>>>  .../bindings/clock/amlogic,meson8b-clkc.txt        |   9 +-
>>>  arch/arm/boot/dts/meson8.dtsi                      |   1 +
>>>  arch/arm/boot/dts/meson8b.dtsi                     |   1 +
>>>  drivers/clk/meson/Kconfig                          |   1 +
>>>  drivers/clk/meson/meson8b.c                        | 159 +++++++++++++++++++-
>>> -
>>>  drivers/clk/meson/meson8b.h                        |   9 +-
>>>  .../dt-bindings/reset/amlogic,meson8b-clkc-reset.h |  27 ++++
>>>  7 files changed, 193 insertions(+), 14 deletions(-)
>>>  create mode 100644 include/dt-bindings/reset/amlogic,meson8b-clkc-reset.h
>>>
>>
>> Series looks good to me overall.
>>
>> Acked-by: Jerome Brunet <jbrunet at baylibre.com>
>>
>> Just one thing, which is not an issue really, I wonder if the dt-bindings
>> documentation and the bindings them-self should be in separate patches ?
>>
>
> Hi Martin,
>
> Anyway it's OK for me, I've applied patches 1 & 2 on the clk-meson's next branches.
thank you!
I'm also fine with either way - I chose to include it in the
dt-bindings patch due to two reasons:
- my SMP series depends on this header file
- we typically send header updates with a dt-bindings patch (see your
AO CEC clock for example)
with these I thought it makes sense to combine the documentation and
the header in the dt-bindings patch - if it's an issue I can simply
change it

may be the DT-maintainers can comment on this?

anyway, thanks for taking care!

> Kevin, patch 3 is all yours !
>
> Thanks,
> Neil


Martin