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1ML-AHB interconnect bindings
2
3These bindings describe the STM32 SoCs ML-AHB interconnect bus which connects
4a Cortex-M subsystem with dedicated memories.
5The MCU SRAM and RETRAM memory parts can be accessed through different addresses
6(see "RAM aliases" in [1]) using different buses (see [2]) : balancing the
7Cortex-M firmware accesses among those ports allows to tune the system
8performance.
9
10[1]: https://www.st.com/resource/en/reference_manual/dm00327659.pdf
11[2]: https://wiki.st.com/stm32mpu/wiki/STM32MP15_RAM_mapping
12
13Required properties:
14- compatible: should be "simple-bus"
15- dma-ranges: describes memory addresses translation between the local CPU and
16	   the remote Cortex-M processor. Each memory region, is declared with
17	   3 parameters:
18		 - param 1: device base address (Cortex-M processor address)
19		 - param 2: physical base address (local CPU address)
20		 - param 3: size of the memory region.
21
22The Cortex-M remote processor accessed via the mlahb interconnect is described
23by a child node.
24
25Example:
26mlahb {
27	compatible = "simple-bus";
28	#address-cells = <1>;
29	#size-cells = <1>;
30	dma-ranges = <0x00000000 0x38000000 0x10000>,
31		     <0x10000000 0x10000000 0x60000>,
32		     <0x30000000 0x30000000 0x60000>;
33
34	m4_rproc: m4@10000000 {
35		...
36	};
37};
38