Implement Physical Memory Protection (PMP) Check for RISC-V

[latifbhatti]

This PR implements a Python-based tool to validate memory access permissions using the Physical Memory Protection (PMP) rules defined in the RISC-V Privileged Specification (Chapter 3.7). The tool checks if a given physical address is accessible under the configured PMP rules for a specific privilege mode and operation.
Features

• Parses PMP configuration files.
• Calculates PMP regions based on address matching modes (TOR, NA4, NAPOT).
• Validates memory access for a given address, privilege mode, and operation.
• Included input validation for hexadecimal addresses, privilege modes, and operations.
• Added error handling for invalid inputs and edge cases.
• writed latex code for understanding the rules
• Reads 128-line configuration files (64 pmpcfg and 64 pmpaddr values).
• Checks access permissions for M, S, and U privilege modes.
• Validates R (read), W (write), and X (execute) operations.

Command-Line Interface:
Accepts four arguments: PMP config file, physical address, privilege mode, and operation.
Example Usage

python pmp_check.py pmp_config.txt 0xc3000100 S R

Output:

Access allowed.

Configuration File Format

• First 64 lines: pmpcfg values (hexadecimal).
• Next 64 lines: pmpaddr values (hexadecimal).

Testing
Tested with various PMP configurations, including:

• Valid and invalid physical addresses.
• Different privilege modes and operations.

References
RISC-V Privileged Specification (Chapter 3.7)

Contributor
latifbhatti