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Diffstat (limited to 'doc/device-tree-bindings/clock/st,stm32-rcc.txt')
-rw-r--r-- | doc/device-tree-bindings/clock/st,stm32-rcc.txt | 95 |
1 files changed, 0 insertions, 95 deletions
diff --git a/doc/device-tree-bindings/clock/st,stm32-rcc.txt b/doc/device-tree-bindings/clock/st,stm32-rcc.txt deleted file mode 100644 index 0532d815da..0000000000 --- a/doc/device-tree-bindings/clock/st,stm32-rcc.txt +++ /dev/null @@ -1,95 +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" -- 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. - -Example: - - rcc: rcc@40023800 { - #reset-cells = <1>; - #clock-cells = <2> - compatible = "st,stm32f42xx-rcc", "st,stm32-rcc"; - reg = <0x40023800 0x400>; - }; - -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 - -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)>; - }; |