Add DMA, DMA Lite, and DMA4 support for BCM2711

[Copilot]

BCM2711 has three distinct DMA engine types with different register maps and control blocks. This PR implements type-safe support for all three variants while avoiding virtual function overhead.

Implementation

Architecture

• CRTP base class (DmaBase<Derived, DmaTag>) provides shared functionality with compile-time dispatch
• Type traits (DmaTraits<DmaTag>) associate register maps and control blocks with each DMA type
• Zero overhead: No virtual functions, all polymorphism resolved at compile time

DMA Types

// Standard DMA (channels 0-6, 8-10): 32-bit addressing
auto dma = Dma::GetInstance(Dma::Channel::kChannel0);
auto* cb = dma_memory.AllocateObject<DmaControlBlock>();
Dma::ConfigureMemoryToMemory(cb, src_phys, dst_phys, size);

// DMA Lite (channel 7): Simplified for basic operations
auto dma_lite = DmaLite::GetInstance(DmaLite::Channel::kChannel7);
auto* cb = dma_memory.AllocateObject<DmaLiteControlBlock>();

// DMA4 (channels 11-14): 40-bit addressing for >1GB RAM
auto dma4 = Dma4::GetInstance(Dma4::Channel::kChannel11);
auto* cb = dma_memory.AllocateObject<Dma4ControlBlock>();
Dma4::ConfigureMemoryToMemory(cb, src_phys_64, dst_phys_64, size);  // 40-bit addresses

Key Files

• dma_base.hpp: CRTP base with common methods (Enable, Reset, Start, WaitForCompletion, etc.)
• dma_standard.hpp/cpp: Standard DMA (channels 0-6, 8-10)
• dma_lite.hpp/cpp: DMA Lite (channel 7)
• dma4.hpp/cpp: DMA4 with 40-bit addressing (channels 11-14)
• registers_dma.hpp: Added Dma4RegisterMap and Dma4ControlBlock with split address fields

Register Mapping

• Channels 11-14 mapped only to Dma4RegisterMap (not DmaRegisterMap)
• REG_DMA11-14 set to nullptr to prevent misuse
• Channel 15 not available on BCM2711

Example

dma_types_example.cpp demonstrates all three types with performance comparison and verification.

Backward Compatibility

include/rpl4/peripheral/dma.hpp now includes all three types. Existing code using Dma class unchanged.

Original prompt

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This section details on the original issue you should resolve

<issue_title>DMA, DMALite, DMA4対応</issue_title>
<issue_description>- raspberry pi 4のDMAは3種類ありらそれぞれレジスタマップとControl Blockが異なる。

• なるべくメモリアクセスが少なくなるように、コンパイル時に多くが確定するように、これらのDMAを共通に扱えるようにする
• 共通機能は同じ実装が使えるので、ベースクラスに機能を追加する形で各DMAクラスを実装すれば良さそうです。
• 仮想関数はなるべく避けたいです
• 最初の一回の初期化時に処理が増えるのは許容します
• DMAの仕様はBCM2711のデータシートを参照してください
• それぞれのDMAの違いを把握するのにちょうど良いexampleを追加で実装してください</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes DMA, DMALite, DMA4対応 #5

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