hal/arm: per-process MPU configuration

[etiaro]

This commit introduces loader support for full MPU regions reconfiguration on context switch, allowing for more flexibile configuration of memory maps on MPU targets.

Changes include

• MPU configuration during app command, based on hal_syspage_prog_t structure with program configuration of MPU regions in form of ready-to-copy register values
• reimplementation of mpu command, showing generated mpu configuration on per-app basis
• passing all maps at once to hal/mpu module, allowing future map merging to reduce count of used MPU regions

JIRA: RTOS-1149

Description

Motivation and Context

This change enables users to define more memory maps, allowing more flexible configuration and better spatial separation of processes, which is first stage of development of partitioning mechanism.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Chore (refactoring, style fixes, git/CI config, submodule management, no code logic changes)

How Has This Been Tested?

• Already covered by automatic testing.
• New test added: (add PR link here).
• Tested by hand on: (list targets here).

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing linter checks and tests passed.
• My changes generate no new compilation warnings for any of the targets.

Special treatment

• test results available in [DO NOT MERGE] context switch with full MPU reconfiguration phoenix-rtos-project#1483
• This PR needs additional PRs to work (list the PRs, preferably in merge-order).
• hal/arm: pmap_switch full MPU reconfiguration phoenix-rtos-kernel#718
• I will merge this PR by myself when appropriate.

[gemini-code-assist]

Summary of Changes

Hello @etiaro, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces a significant architectural enhancement to the Memory Protection Unit (MPU) management system. By shifting from a global MPU configuration to a per-process model, it enables dynamic and flexible memory mapping for individual applications. This change is crucial for improving spatial separation between processes and forms the foundational stage for developing more robust partitioning mechanisms within the system. The refactoring impacts how MPU regions are allocated, managed, and displayed, providing greater control and visibility over memory access permissions for each running program.

Highlights

• Per-Process MPU Configuration: Introduces loader support for full MPU region reconfiguration on context switch, enabling more flexible memory map configurations tailored to individual processes on MPU targets.
• Reimplemented MPU Command: The mpu command has been reimplemented to display MPU configuration on a per-application basis, allowing users to inspect the memory protection settings for specific programs.
• Unified Map Passing: All memory maps are now passed at once to the hal/mpu module, which paves the way for future optimizations like map merging to reduce the total count of used MPU regions.
• HAL API Update: The hal_memoryAddMap function has been replaced with hal_getProgData, which now accepts a syspage_prog_t structure to populate program-specific MPU configurations.
• MPU Module Refactoring: The core MPU logic in hal/armv7m/mpu.c, hal/armv7r/mpu.c, and hal/armv8m/mpu.c has been refactored to operate on a per-program context, moving away from a global MPU state for region allocation and management.

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[gemini-code-assist]

Code Review

This pull request introduces a significant and valuable feature: per-process MPU configuration. The changes are extensive, touching multiple architectures to refactor MPU handling from a global to a per-program basis. The core logic in mpu.c files for ARMv7-M, ARMv7-R, and ARMv8-M has been substantially rewritten to support this new model, and the mpu command has been updated accordingly. My review has identified a few areas for improvement, including a critical missing function for ARMv8-M that would cause build failures, some redundant error logging, a leftover logic bug in syspage.c, and an inconsistency in MPU region invalidation logic. Addressing these points will enhance the robustness and maintainability of this new feature.