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[79.41.6.15]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-5d9900c4b56sm925567a12.32.2025.01.09.13.19.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 09 Jan 2025 13:19:15 -0800 (PST) From: Dario Binacchi To: linux-kernel@vger.kernel.org Cc: linux-amarula@amarulasolutions.com, Dario Binacchi , Alexandre Torgue , Conor Dooley , Krzysztof Kozlowski , Maxime Coquelin , Michael Turquette , Philipp Zabel , Rob Herring , Stephen Boyd , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-clk@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com Subject: [PATCH v2 1/4] dt-bindings: clock: convert stm32 rcc bindings to json-schema Date: Thu, 9 Jan 2025 22:18:28 +0100 Message-ID: <20250109211908.1553072-2-dario.binacchi@amarulasolutions.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250109211908.1553072-1-dario.binacchi@amarulasolutions.com> References: <20250109211908.1553072-1-dario.binacchi@amarulasolutions.com> MIME-Version: 1.0 X-Original-Sender: dario.binacchi@amarulasolutions.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@amarulasolutions.com header.s=google header.b=ZxInToGI; spf=pass (google.com: domain of dario.binacchi@amarulasolutions.com designates 209.85.220.41 as permitted sender) smtp.mailfrom=dario.binacchi@amarulasolutions.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=amarulasolutions.com; dara=pass header.i=@amarulasolutions.com Content-Type: text/plain; charset="UTF-8" Precedence: list Mailing-list: list linux-amarula@amarulasolutions.com; contact linux-amarula+owners@amarulasolutions.com List-ID: X-Spam-Checked-In-Group: linux-amarula@amarulasolutions.com X-Google-Group-Id: 476853432473 List-Post: , List-Help: , List-Archive: List-Unsubscribe: , The patch converts st,stm32-rcc.txt to the JSON schema, but it does more than that. The old bindings, in fact, only covered the stm32f{4,7} platforms and not the stm32h7. Therefore, to avoid patch submission tests failing, it was necessary to add the corresponding compatible (i. e. st,stm32h743-rcc) and specify that, in this case, 3 are the clocks instead of the 2 required for the stm32f{4,7} platforms. Additionally, the old bindings made no mention of the st,syscfg property, which is used by both the stm32f{4,7} and the stm32h7 platforms. The patch also fixes the files referencing to the old st,stm32-rcc.txt. Signed-off-by: Dario Binacchi Reviewed-by: Krzysztof Kozlowski --- Changes in v2: - Fixup patches: 2/6 dt-bindings: reset: st,stm32-rcc: update reference due to rename 3/6 dt-bindings: clock: stm32fx: update reference due to rename - Update the commit message - Reduce the description section of the yaml file - List the items with description for the clocks property - Use only one example - Rename rcc to clock-controller@58024400 for the node of the example .../bindings/clock/st,stm32-rcc.txt | 138 ------------------ .../bindings/clock/st,stm32-rcc.yaml | 111 ++++++++++++++ .../bindings/reset/st,stm32-rcc.txt | 2 +- include/dt-bindings/clock/stm32fx-clock.h | 2 +- 4 files changed, 113 insertions(+), 140 deletions(-) delete mode 100644 Documentation/devicetree/bindings/clock/st,stm32-rcc.txt create mode 100644 Documentation/devicetree/bindings/clock/st,stm32-rcc.yaml diff --git a/Documentation/devicetree/bindings/clock/st,stm32-rcc.txt b/Documentation/devicetree/bindings/clock/st,stm32-rcc.txt deleted file mode 100644 index cfa04b614d8a..000000000000 --- a/Documentation/devicetree/bindings/clock/st,stm32-rcc.txt +++ /dev/null @@ -1,138 +0,0 @@ -STMicroelectronics STM32 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,stm32f42xx-rcc" - "st,stm32f469-rcc" - "st,stm32f746-rcc" - "st,stm32f769-rcc" - -- reg: should be register base and length as documented in the - datasheet -- #reset-cells: 1, see below -- #clock-cells: 2, device nodes should specify the clock in their "clocks" - property, containing a phandle to the clock device node, an index selecting - between gated clocks and other clocks and an index specifying the clock to - use. -- clocks: External oscillator clock phandle - - high speed external clock signal (HSE) - - external I2S clock (I2S_CKIN) - -Example: - - rcc: rcc@40023800 { - #reset-cells = <1>; - #clock-cells = <2> - compatible = "st,stm32f42xx-rcc", "st,stm32-rcc"; - reg = <0x40023800 0x400>; - clocks = <&clk_hse>, <&clk_i2s_ckin>; - }; - -Specifying gated clocks -======================= - -The primary index must be set to 0. - -The secondary index is the bit number within the RCC register bank, starting -from the first RCC clock enable register (RCC_AHB1ENR, address offset 0x30). - -It is calculated as: index = register_offset / 4 * 32 + bit_offset. -Where bit_offset is the bit offset within the register (LSB is 0, MSB is 31). - -To simplify the usage and to share bit definition with the reset and clock -drivers of the RCC IP, macros are available to generate the index in -human-readble format. - -For STM32F4 series, the macro are available here: - - include/dt-bindings/mfd/stm32f4-rcc.h - -Example: - - /* Gated clock, AHB1 bit 0 (GPIOA) */ - ... { - clocks = <&rcc 0 STM32F4_AHB1_CLOCK(GPIOA)> - }; - - /* Gated clock, AHB2 bit 4 (CRYP) */ - ... { - clocks = <&rcc 0 STM32F4_AHB2_CLOCK(CRYP)> - }; - -Specifying other clocks -======================= - -The primary index must be set to 1. - -The secondary index is bound with the following magic numbers: - - 0 SYSTICK - 1 FCLK - 2 CLK_LSI (low-power clock source) - 3 CLK_LSE (generated from a 32.768 kHz low-speed external - crystal or ceramic resonator) - 4 CLK_HSE_RTC (HSE division factor for RTC clock) - 5 CLK_RTC (real-time clock) - 6 PLL_VCO_I2S (vco frequency of I2S pll) - 7 PLL_VCO_SAI (vco frequency of SAI pll) - 8 CLK_LCD (LCD-TFT) - 9 CLK_I2S (I2S clocks) - 10 CLK_SAI1 (audio clocks) - 11 CLK_SAI2 - 12 CLK_I2SQ_PDIV (post divisor of pll i2s q divisor) - 13 CLK_SAIQ_PDIV (post divisor of pll sai q divisor) - - 14 CLK_HSI (Internal ocscillator clock) - 15 CLK_SYSCLK (System Clock) - 16 CLK_HDMI_CEC (HDMI-CEC clock) - 17 CLK_SPDIF (SPDIF-Rx clock) - 18 CLK_USART1 (U(s)arts clocks) - 19 CLK_USART2 - 20 CLK_USART3 - 21 CLK_UART4 - 22 CLK_UART5 - 23 CLK_USART6 - 24 CLK_UART7 - 25 CLK_UART8 - 26 CLK_I2C1 (I2S clocks) - 27 CLK_I2C2 - 28 CLK_I2C3 - 29 CLK_I2C4 - 30 CLK_LPTIMER (LPTimer1 clock) - 31 CLK_PLL_SRC - 32 CLK_DFSDM1 - 33 CLK_ADFSDM1 - 34 CLK_F769_DSI -) - -Example: - - /* Misc clock, FCLK */ - ... { - clocks = <&rcc 1 STM32F4_APB1_CLOCK(TIM2)> - }; - - -Specifying softreset control of devices -======================================= - -Device nodes should specify the reset channel required in their "resets" -property, containing a phandle to the reset device node and an index specifying -which channel to use. -The index is the bit number within the RCC registers bank, starting from RCC -base address. -It is calculated as: index = register_offset / 4 * 32 + bit_offset. -Where bit_offset is the bit offset within the register. -For example, for CRC reset: - crc = AHB1RSTR_offset / 4 * 32 + CRCRST_bit_offset = 0x10 / 4 * 32 + 12 = 140 - -example: - - timer2 { - resets = <&rcc STM32F4_APB1_RESET(TIM2)>; - }; diff --git a/Documentation/devicetree/bindings/clock/st,stm32-rcc.yaml b/Documentation/devicetree/bindings/clock/st,stm32-rcc.yaml new file mode 100644 index 000000000000..779e547700be --- /dev/null +++ b/Documentation/devicetree/bindings/clock/st,stm32-rcc.yaml @@ -0,0 +1,111 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/clock/st,stm32-rcc.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: STMicroelectronics STM32 Reset Clock Controller + +maintainers: + - Dario Binacchi + +description: | + The RCC IP is both a reset and a clock controller. + The reset phandle argument is the bit number within the RCC registers bank, + starting from RCC base address. + +properties: + compatible: + oneOf: + - items: + - const: st,stm32f42xx-rcc + - const: st,stm32-rcc + - items: + - enum: + - st,stm32f469-rcc + - const: st,stm32f42xx-rcc + - const: st,stm32-rcc + - items: + - const: st,stm32f746-rcc + - const: st,stm32-rcc + - items: + - enum: + - st,stm32f769-rcc + - const: st,stm32f746-rcc + - const: st,stm32-rcc + - items: + - const: st,stm32h743-rcc + - const: st,stm32-rcc + + reg: + maxItems: 1 + + '#reset-cells': + const: 1 + + '#clock-cells': + enum: [1, 2] + + clocks: + minItems: 2 + maxItems: 3 + + st,syscfg: + $ref: /schemas/types.yaml#/definitions/phandle + description: + Phandle to system configuration controller. It can be used to control the + power domain circuitry. + +required: + - compatible + - reg + - '#reset-cells' + - '#clock-cells' + - clocks + - st,syscfg + +allOf: + - if: + properties: + compatible: + contains: + const: st,stm32h743-rcc + then: + properties: + '#clock-cells': + const: 1 + description: | + The clock index for the specified type. + clocks: + items: + - description: high speed external (HSE) clock input + - description: low speed external (LSE) clock input + - description: Inter-IC sound (I2S) clock input + else: + properties: + '#clock-cells': + const: 2 + description: | + - The first cell is the clock type, possible values are 0 for + gated clocks and 1 otherwise. + - The second cell is the clock index for the specified type. + clocks: + items: + - description: high speed external (HSE) clock input + - description: Inter-IC sound (I2S) clock input + +additionalProperties: false + +examples: + # Reset and Clock Control Module node: + - | + clock-controller@58024400 { + compatible = "st,stm32h743-rcc", "st,stm32-rcc"; + reg = <0x58024400 0x400>; + #clock-cells = <1>; + #reset-cells = <1>; + clocks = <&clk_hse>, <&clk_lse>, <&clk_i2s>; + st,syscfg = <&pwrcfg>; + }; + +... diff --git a/Documentation/devicetree/bindings/reset/st,stm32-rcc.txt b/Documentation/devicetree/bindings/reset/st,stm32-rcc.txt index 01db34375192..384035e8e60b 100644 --- a/Documentation/devicetree/bindings/reset/st,stm32-rcc.txt +++ b/Documentation/devicetree/bindings/reset/st,stm32-rcc.txt @@ -3,4 +3,4 @@ STMicroelectronics STM32 Peripheral Reset Controller The RCC IP is both a reset and a clock controller. -Please see Documentation/devicetree/bindings/clock/st,stm32-rcc.txt +Please see Documentation/devicetree/bindings/clock/st,stm32-rcc.yaml diff --git a/include/dt-bindings/clock/stm32fx-clock.h b/include/dt-bindings/clock/stm32fx-clock.h index e5dad050d518..b6ff9c68cb3f 100644 --- a/include/dt-bindings/clock/stm32fx-clock.h +++ b/include/dt-bindings/clock/stm32fx-clock.h @@ -10,7 +10,7 @@ * List of clocks which are not derived from system clock (SYSCLOCK) * * The index of these clocks is the secondary index of DT bindings - * (see Documentation/devicetree/bindings/clock/st,stm32-rcc.txt) + * (see Documentation/devicetree/bindings/clock/st,stm32-rcc.yaml) * * e.g: ;