From: gabriel.fernandez@st.com (Gabriel Fernandez)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] clk: stm32h7: Add stm32h743 clock driver
Date: Fri, 28 Apr 2017 16:56:16 +0200 [thread overview]
Message-ID: <7a8082a9-e62c-0120-e680-bef63eb892ae@st.com> (raw)
In-Reply-To: <20170407195152.GH7065@codeaurora.org>
Hi Stephen
Sorry for delay i was on sick live
On 04/07/2017 09:51 PM, Stephen Boyd wrote:
> On 04/06, Gabriel Fernandez wrote:
>> On 04/06/2017 12:32 AM, Stephen Boyd wrote:
>>> On 03/15, gabriel.fernandez at st.com wrote:
>>>> diff --git a/Documentation/devicetree/bindings/clock/st,stm32h7-rcc.txt b/Documentation/devicetree/bindings/clock/st,stm32h7-rcc.txt
>>>> new file mode 100644
>>>> index 0000000..9d4b587
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/clock/st,stm32h7-rcc.txt
>>>> @@ -0,0 +1,152 @@
>>>> +
>>>> + rcc: rcc at 58024400 {
>>>> + #reset-cells = <1>;
>>>> + #clock-cells = <2>
>>>> + compatible = "st,stm32h743-rcc", "st,stm32-rcc";
>>>> + reg = <0x58024400 0x400>;
>>>> + clocks = <&clk_hse>, <&clk_lse>, <&clk_i2s_ckin>;
>>>> +
>>>> + st,syscfg = <&pwrcfg>;
>>>> +
>>>> + #address-cells = <1>;
>>>> + #size-cells = <0>;
>>>> +
>>>> + vco1 at 58024430 {
>>>> + #clock-cells = <0>;
>>>> + compatible = "stm32,pll";
>>>> + reg = <0>;
>>> reg is super confusing and doesn't match unit address.
>> ok i fixed it in the v2
>>
>>>> + };
>>> Why? Shouldn't we know this from the compatible string how many
>>> PLLs there are and where they're located? Export the PLLs through
>>> rcc node's clock-cells?
>>>
>> Because i need to offer the possibility to change the PLL VCO
>> frequencies at the start-up of this driver clock.
>> The VCO algorithm needs a division factor, a multiplication factor
>> and a fractional factor.
>> Lot's of solution are possible for one frequency and it's nightmare
>> to satisfy the 3 output dividers of the PLL.
> Sure, but do we need to configure that on a per-board basis or a
> per-SoC basis? If it's just some configuration, I wonder why we
> don't put that into the driver and base it off some compatible
> string that includes the SoC the device is for.
>
I prefer to let in first, the responsibility of the boot loader to
change VCO parameters.
Then i propose a new version without DT configuration of PLL's
are you ok for that ?
best regards
Gabriel
To simply
prev parent reply other threads:[~2017-04-28 14:56 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-03-15 9:23 [PATCH] clk: stm32h7: Add stm32h743 clock driver gabriel.fernandez at st.com
2017-03-15 12:15 ` Lee Jones
2017-03-24 2:06 ` Rob Herring
2017-03-24 9:41 ` Gabriel Fernandez
2017-03-27 19:04 ` Rob Herring
2017-03-28 6:20 ` Gabriel Fernandez
2017-03-28 15:19 ` Rob Herring
2017-04-05 22:32 ` Stephen Boyd
2017-04-06 9:35 ` Gabriel Fernandez
2017-04-07 19:51 ` Stephen Boyd
2017-04-28 14:56 ` Gabriel Fernandez [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=7a8082a9-e62c-0120-e680-bef63eb892ae@st.com \
--to=gabriel.fernandez@st.com \
--cc=linux-arm-kernel@lists.infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).