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Groups > linux.kernel > #1610357
| From | Gabriel Fernandez <gabriel.fernandez@st.com> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: [PATCH] clk: stm32h7: Add stm32h743 clock driver |
| Date | 2017-03-28 08:30 +0200 |
| Message-ID | <tpSNH-3ya-1@gated-at.bofh.it> (permalink) |
| References | <tldpL-5Cc-3@gated-at.bofh.it> <tomPT-2V6-1@gated-at.bofh.it> <tou14-80L-11@gated-at.bofh.it> <tpIbD-4oN-1@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
On 03/27/2017 09:04 PM, Rob Herring wrote:
> On Fri, Mar 24, 2017 at 4:41 AM, Gabriel Fernandez
> <gabriel.fernandez@st.com> wrote:
>> Hi Rob,
>>
>> Thanks for reviewing
>>
>>
>>
>> On 03/24/2017 03:06 AM, Rob Herring wrote:
>>> On Wed, Mar 15, 2017 at 10:23:30AM +0100, gabriel.fernandez@st.com wrote:
>>>> From: Gabriel Fernandez <gabriel.fernandez@st.com>
>>>>
>>>> This patch enables clocks for STM32H743 boards.
>>>>
>>>> Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
>>>> ---
>>>> .../devicetree/bindings/clock/st,stm32h7-rcc.txt | 152 ++
>>>> drivers/clk/Makefile | 1 +
>>>> drivers/clk/clk-stm32h7.c | 1586
>>>> ++++++++++++++++++++
>>>> include/dt-bindings/clock/stm32h7-clks.h | 165 ++
>>>> include/dt-bindings/mfd/stm32h7-rcc.h | 138 ++
>>>> 5 files changed, 2042 insertions(+)
>>>> create mode 100644
>>>> Documentation/devicetree/bindings/clock/st,stm32h7-rcc.txt
>>>> create mode 100644 drivers/clk/clk-stm32h7.c
>>>> create mode 100644 include/dt-bindings/clock/stm32h7-clks.h
>>>> create mode 100644 include/dt-bindings/mfd/stm32h7-rcc.h
>>>>
>>>> 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 @@
>>>> +STMicroelectronics STM32H7 Reset and Clock Controller
>>>> +=====================================================
>>>> +
>>>> +The RCC IP is both a reset and a clock controller.
>>>> +
>>>> +Please refer to clock-bindings.txt for common clock controller binding
>>>> usage.
>>>> +Please also refer to reset.txt for common reset controller binding
>>>> usage.
>>>> +
>>>> +Required properties:
>>>> +- compatible: Should be:
>>>> + "st,stm32h743-rcc"
>>>> +
>>>> +- reg: should be register base and length as documented in the
>>>> + datasheet
>>>> +
>>>> +- #reset-cells: 1, see below
>>>> +
>>>> +- #clock-cells : from common clock binding; shall be set to 1
>>>> +
>>>> +- clocks: External oscillator clock phandle
>>>> + - high speed external clock signal (HSE)
>>>> + - low speed external clock signal (LSE)
>>>> + - external I2S clock (I2S_CKIN)
>>>> +
>>>> +- st,syscfg: phandle for pwrcfg, mandatory to disable/enable backup
>>>> domain
>>>> + write protection (RTC clock).
>>>> +
>>>> +- pll x node: Allow to register a pll with specific parameters.
>>>> + Please see PLL section below.
>>>> +
>>>> +Example:
>>>> +
>>>> + rcc: rcc@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@58024430 {
>>>> + #clock-cells = <0>;
>>>> + compatible = "stm32,pll";
>>>> + reg = <0>;
>>> The reg addr value and unit address don't match.
>> ok il will change into
>>
>> vco1@0 {
>> reg = <0>;
>>
>>
>>>> + };
>>>> +
>>>> + vco2@58024438 {
>>>> + #clock-cells = <0>;
>>>> + compatible = "stm32,pll";
>>>> + reg = <1>;
>>>> + st,clock-div = <2>;
>>>> + st,clock-mult = <40>;
>>>> + st,frac-status = <0>;
>>>> + st,frac = <0>;
>>>> + st,vcosel = <1>;
>>>> + st,pllrge = <2>;
>>>> + };
>>>> + };
>>>> +
>>>> +
>>>> +STM32H7 PLL
>>>> +-----------
>>>> +
>>>> +The VCO of STM32 PLL could be reprensented like this:
>>>> +
>>>> + Vref --------- --------
>>>> + ---->| / DIVM |---->| x DIVN | ------> VCO
>>>> + --------- --------
>>>> + ^
>>>> + |
>>>> + -------
>>>> + | FRACN |
>>>> + -------
>>>> +
>>>> +When the PLL is configured in integer mode:
>>>> +- VCO = ( Vref / DIVM ) * DIVN
>>>> +
>>>> +When the PLL is configured in fractional mode:
>>>> +- VCO = ( Vref / DIVM ) * ( DIVN + FRACN / 2^13)
>>>> +
>>>> +
>>>> +Required properties for pll node:
>>>> +- compatible: Should be:
>>>> + "stm32,pll"
>>> Only 1 single PLL design for all STM32 chips ever?
>> no, i can change into "stm32h7,pll"
> Actually, should be "st,stm32h7-pll".
ok
>>>> +
>>>> +- #clock-cells: from common clock binding; shall be set to 0
>>>> +- reg: Should be the pll number.
>>>> +
>>>> +Optional properties:
>>>> +- st,clock-div: DIVM division factor : <1..63>
>>>> +- st,clock-mult: DIVN multiplication factor : <4..512>
>>>> +
>>>> +- st,frac-status:
>>>> + - 0 Pll is configured in integer mode
>>>> + - 1 Pll is configure in fractional mode
>>> Isn't this implied by the presence of the next property?
>> do you prefer this ?
>>
>> - st,frac :
>> 0 : pll is configured in integer mode
>> 1..8191 : Fractional part of the multiplication factor and pll is configured
>> in fractional mode
> Why not no st,frac property means integer mode?
No
no st,frac property means no change (keep default values from bootloader)
Best Regards
Gabriel
> Rob
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Re: [PATCH] clk: stm32h7: Add stm32h743 clock driver Rob Herring <robh@kernel.org> - 2017-03-24 03:10 +0100
Re: [PATCH] clk: stm32h7: Add stm32h743 clock driver Gabriel Fernandez <gabriel.fernandez@st.com> - 2017-03-24 10:50 +0100
Re: [PATCH] clk: stm32h7: Add stm32h743 clock driver Rob Herring <robh@kernel.org> - 2017-03-27 21:10 +0200
Re: [PATCH] clk: stm32h7: Add stm32h743 clock driver Gabriel Fernandez <gabriel.fernandez@st.com> - 2017-03-28 08:30 +0200
Re: [PATCH] clk: stm32h7: Add stm32h743 clock driver Rob Herring <robh@kernel.org> - 2017-03-28 17:30 +0200
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