ADD: add introduction to toolchain

tutorials/software/setting-up-riscv-environment.md

@@ -17,3 +17,37 @@ In this tutorial, we will set up the RISC-V environment by installing necessary
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 > **Note**: RISC-V 64 bit toolchains is by default available on BWRC machines. Only follow the link to set up RISC-V 32 bit support for debugging RV32 systems. 
+
+## What is a RISC-V Toolchain?
+
+The `riscv64-unknown-elf-xxx` toolchain is specifically designed for the RISC-V instruction set architecture (ISA), and it's used for developing bare-metal and applications for running on RISC-V targets. This toolchain typically runs on the host machine (e.g., an x86-based PC) to produce code that will run on a RISC-V machine (e.g., a RISC-V based SoC). This process is known as cross-compilation.
+
+Breaking down the name riscv64-unknown-elf-xxx:
+
+`riscv64`: This refers to the RISC-V architecture with a 64-bit address space. RISC-V is an open-standard ISA that's been gaining traction in both academia and industry due to its flexibility and modularity.
+
+`unknown`: This indicates that the toolchain is not tied to a specific vendor or platform. It's a generic term used to describe that the toolchain can be used across different RISC-V implementations.
+
+`elf`: Stands for Executable and Linkable Format. It's the format used for the compiled binaries. ELF is a common binary file format that's used on many Unix systems, including Linux.
+
+`xxx`: Typically, this would be replaced by specific tools within the toolchain, like:
+
+- gcc: The GNU Compiler Collection for RISC-V, also known as **the compiler**.
+- gdb: The GNU Debugger for debugging RISC-V applications, used for debugging programs.
+- ld: The **linker**.
+- objdump: A utility that displays information about object files.
+- ... and so on
+
+## What is OpenOCD?
+
+OpenOCD, which stands for Open On-Chip Debugger, is a free, open-source software that provides debugging, in-system programming, and boundary-scan testing for embedded systems. It's used to program and debug embedded systems using JTAG or SWD (Serial Wire Debug) interfaces.
+
+### Main functionalities
+
+**Debugging**: Through OpenOCD, developers can control the JTAG state machine to run a program on an embedded target, halt the target at a breakpoint, and then inspect or modify variables to debug the software.
+
+**Flashing**: OpenOCD can be used to load program (also called "flash") onto either internal or external Flash memory of the SoC. 
+
+**Remote Debugging**: OpenOCD can function as a GDB (GNU Debugger) server. This means developers can use GDB or a GDB-compatible front-end to remotely debug an application running on an embedded target through OpenOCD.
+
+**Scriptable Interface**: OpenOCD provides a flexible and scriptable interface, which is valuable for automated testing and custom debugging routines.