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Subject[PATCH v2 01/12] dt-bindings: Document STM32MP1 Reset Clock Controller (RCC) bindings
Date
From: Gabriel Fernandez <gabriel.fernandez@st.com>

The RCC block is responsible of the management of the clock and reset
generation for the complete circuit.

Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
---
.../devicetree/bindings/clock/st,stm32mp1-rcc.txt | 60 ++++++++++++++++++++++
1 file changed, 60 insertions(+)
create mode 100644 Documentation/devicetree/bindings/clock/st,stm32mp1-rcc.txt

diff --git a/Documentation/devicetree/bindings/clock/st,stm32mp1-rcc.txt b/Documentation/devicetree/bindings/clock/st,stm32mp1-rcc.txt
new file mode 100644
index 0000000..fb9495e
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/st,stm32mp1-rcc.txt
@@ -0,0 +1,60 @@
+STMicroelectronics STM32 Peripheral Reset Clock Controller
+==========================================================
+
+The RCC IP is both a reset and a clock controller.
+
+RCC makes also power management (resume/supend and wakeup interrupt).
+
+Please also refer to reset.txt for common reset controller binding usage.
+
+Please also refer to clock-bindings.txt for common clock controller
+binding usage.
+
+
+Required properties:
+- compatible: "st,stm32mp1-rcc", "syscon"
+- reg: should be register base and length as documented in the datasheet
+- #clock-cells: 1, device nodes should specify the clock in their
+ "clocks" property, containing a phandle to the clock device node,
+ an index specifying the clock to use.
+- #reset-cells: Shall be 1
+- interrupts: Should contain a general interrupt line and a interrupt line
+ to the wake-up of processor (CSTOP).
+
+Example:
+ rcc: rcc@50000000 {
+ compatible = "st,stm32mp1-rcc", "syscon";
+ reg = <0x50000000 0x1000>;
+ #clock-cells = <1>;
+ #reset-cells = <1>;
+ interrupts = <GIC_SPI 5 IRQ_TYPE_NONE>,
+ <GIC_SPI 145 IRQ_TYPE_NONE>;
+ };
+
+Specifying clocks
+=================
+
+All available clocks are defined as preprocessor macros in
+dt-bindings/clock/stm32mp1-clks.h header and can be used in device
+tree sources.
+
+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 on STM32MP1, for LTDC reset:
+ ltdc = APB4_RSTSETR_offset / 4 * 32 + LTDC_bit_offset
+ = 0x180 / 4 * 32 + 0 = 3072
+
+The list of valid indices for STM32MP1 is available in:
+include/dt-bindings/reset-controller/stm32mp1-resets.h
+
+This file implements defines like:
+#define LTDC_R 3072
--
1.9.1
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