Adjust flash size from 2M to 4M for Arduino MMU compatibility

[Jason2866]

Description:

fix for crashing ESP32-C2 2MB and all other ESP32x variants with 2MB in Hybrid Compile mode.

Checklist:

• The pull request is done against the latest develop branch
• Only relevant files were touched
• Only one feature/fix was added per PR, more changes are allowed when changing boards.json
• I accept the CLA

Summary by CodeRabbit

• Bug Fixes
  • Improved flash memory configuration handling to ensure proper compatibility with specific board setups requiring adjusted memory allocation initialization.

[Jason2866]

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📝 Walkthrough

Walkthrough

A logic override is added to the flash size configuration in the ESP-IDF builder. When flash size is detected as "2MB", the system logs an informational message and remaps it to "4MB" to ensure Arduino MMU page size compatibility.

Changes

Cohort / File(s)	Summary
Flash Size Configuration Override builder/frameworks/espidf.py	Added conditional logic in generate_board_specific_config to detect "2MB" flash size, log an informational message, and remap the value to "4MB" for Arduino MMU compatibility.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~5 minutes

Possibly related PRs

• HybridCompile: Refactor sdkconfig generation from boards json and add P4 #316: Modifies the same generate_board_specific_config function and touches board flash-related configuration logic.

Poem

🐰 A flash that was small, just two megs in size,
Now quietly grows to four, much to our surprise!
The Arduino MMU smiles with glee,
As compatibility hops wild and free! 🌟

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title directly reflects the main change: remapping flash size from 2MB to 4MB for Arduino MMU compatibility, which matches the core modification in the code.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch fix_C2_2M_hybrid

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✅ Actions performed

Full review triggered.

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Actionable comments posted: 2

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@builder/frameworks/espidf.py`:
- Line 424: The print call uses an unnecessary f-string with no placeholders;
replace the print(f"Info: Detected 2MB flash size setting, override to 4MB for
Arduino MMU page size compatibility") with a plain string print("Info: Detected
2MB flash size setting, override to 4MB for Arduino MMU page size
compatibility") to remove the unused f-prefix in the print statement.
- Around line 423-425: generate_board_specific_config currently forces
flash_size="4MB" for any 2MB board but later the mismatch check still reads the
original board.get("upload.flash_size") into board_flash_size causing a spurious
warning; fix by applying the same remapping when computing board_flash_size
(i.e. normalize board.get("upload.flash_size") the same way you normalized
flash_size) or skip the mismatch check when the override flag is set, and
tighten the override guard so it only applies to esp32c2 (restrict the condition
that sets flash_size to "4MB" to MCU "esp32c2"); update references to
flash_size, board_flash_size, idf_flash_size and the SDK key
"ESPTOOLPY_FLASHSIZE" so both sides use the same normalized value.

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ℹ️ Review info

Configuration used: defaults

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between c28413a and 50f69c8.

📒 Files selected for processing (1)

• builder/frameworks/espidf.py