Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932185AbdC1PTu (ORCPT ); Tue, 28 Mar 2017 11:19:50 -0400 Received: from mail.kernel.org ([198.145.29.136]:55868 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932091AbdC1PTt (ORCPT ); Tue, 28 Mar 2017 11:19:49 -0400 MIME-Version: 1.0 In-Reply-To: <461b2321-c43c-6d88-c805-97a887cc431d@st.com> References: <1489569810-24350-1-git-send-email-gabriel.fernandez@st.com> <20170324020630.vhffmeeb6wto53zx@rob-hp-laptop> <461b2321-c43c-6d88-c805-97a887cc431d@st.com> From: Rob Herring Date: Tue, 28 Mar 2017 10:19:10 -0500 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] clk: stm32h7: Add stm32h743 clock driver To: Gabriel Fernandez Cc: Mark Rutland , Russell King , Maxime Coquelin , Alexandre Torgue , Michael Turquette , Stephen Boyd , Nicolas Pitre , Arnd Bergmann , Daniel Thompson , Andrea Merello , =?UTF-8?Q?Rados=C5=82aw_Pietrzyk?= , Lee Jones , "devicetree@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , linux-clk , Ludovic Barre , Olivier Bideau , Amelie Delaunay Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6015 Lines: 186 On Tue, Mar 28, 2017 at 1:20 AM, Gabriel Fernandez wrote: > > > On 03/27/2017 09:04 PM, Rob Herring wrote: >> >> On Fri, Mar 24, 2017 at 4:41 AM, Gabriel Fernandez >> 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 >>>>> >>>>> This patch enables clocks for STM32H743 boards. >>>>> >>>>> Signed-off-by: Gabriel Fernandez >>>>> --- >>>>> .../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) Okay, then 0 for integer mode is fine. Also state what the default means. Rob