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authorAmlal El Mahrouss <amlal@nekernel.org>2025-11-24 03:02:43 +0100
committerAmlal El Mahrouss <amlal@nekernel.org>2025-11-24 03:02:43 +0100
commit83d870e58457a1d335a1d9b9966a6a1887cc297b (patch)
tree72888f88c7728c82f3f6df1f4f70591de15eab36 /src/kernel/DmaKit
parentab37adbacf0f33845804c788b39680cd754752a8 (diff)
feat! breaking changes on kernel sources.
Signed-off-by: Amlal El Mahrouss <amlal@nekernel.org>
Diffstat (limited to 'src/kernel/DmaKit')
-rw-r--r--src/kernel/DmaKit/DmaPool.h101
1 files changed, 101 insertions, 0 deletions
diff --git a/src/kernel/DmaKit/DmaPool.h b/src/kernel/DmaKit/DmaPool.h
new file mode 100644
index 00000000..e20f8c69
--- /dev/null
+++ b/src/kernel/DmaKit/DmaPool.h
@@ -0,0 +1,101 @@
+/* ========================================
+
+ Copyright (C) 2025, Amlal El Mahrouss , licensed under the Apache 2.0 license.
+
+ File: DmaPool.h
+ Purpose: Dma Pool Manager.
+
+======================================== */
+
+#pragma once
+
+#include <KernelKit/DebugOutput.h>
+
+#ifdef __NE_AMD64__
+#include <HALKit/AMD64/Processor.h>
+#define kNeDMAPoolStart (0x1000000)
+#define kNeDMAPoolSize (0x1000000)
+#elif defined(__NE_ARM64__)
+#include <HALKit/ARM64/Processor.h>
+
+/// @todo what reference offset shall we use?
+#define kNeDMAPoolStart (0x1000000)
+#define kNeDMAPoolSize (0x1000000)
+#endif
+
+#define kNeDMABestAlign (8)
+
+namespace Kernel {
+/// @brief DMA pool base pointer, here we're sure that AHCI or whatever tricky standard sees it.
+inline UInt8* kDmaPoolPtr = (UInt8*) kNeDMAPoolStart;
+inline const UInt8* kDmaPoolEnd = (UInt8*) (kNeDMAPoolStart + kNeDMAPoolSize);
+
+/***********************************************************************************/
+/// @brief allocate from the rtl_dma_alloc system.
+/// @param size the size of the chunk to allocate.
+/// @param align alignement of pointer.
+/***********************************************************************************/
+inline VoidPtr rtl_dma_alloc(SizeT size, SizeT align) {
+ if (!size) {
+ return nullptr;
+ }
+
+ /// Check alignement according to architecture.
+ if ((align % kNeDMABestAlign) != 0) {
+ return nullptr;
+ }
+
+ UIntPtr addr = (UIntPtr) kDmaPoolPtr;
+
+ /// here we just align the address according to a `align` variable, i'd rather be a power of two
+ /// really.
+ addr = (addr + (align - 1)) & ~(align - 1);
+
+ if ((addr + size) > reinterpret_cast<UIntPtr>(kDmaPoolEnd)) {
+ err_global_get() = kErrorDmaExhausted;
+ return nullptr;
+ }
+
+ kDmaPoolPtr = (UInt8*) (addr + size);
+
+ HAL::mm_memory_fence((VoidPtr) addr);
+
+ return (VoidPtr) addr;
+}
+
+/***********************************************************************************/
+/// @brief Free DMA pointer.
+/***********************************************************************************/
+inline Void rtl_dma_free(SizeT size) {
+ if (!size) return;
+
+ auto ptr = (kDmaPoolPtr - size);
+
+ if (!ptr || ptr < (UInt8*) kNeDMAPoolStart) {
+ err_global_get() = kErrorDmaExhausted;
+ return;
+ }
+
+ kDmaPoolPtr = ptr;
+
+ HAL::mm_memory_fence(ptr);
+}
+
+/***********************************************************************************/
+/// @brief Flush DMA pointer.
+/***********************************************************************************/
+inline Void rtl_dma_flush(VoidPtr ptr, SizeT size_buffer) {
+ if (ptr > kDmaPoolEnd) {
+ return;
+ }
+
+ if (!ptr || ptr < (UInt8*) kNeDMAPoolStart) {
+ err_global_get() = kErrorDmaExhausted;
+ return;
+ }
+
+ for (SizeT buf_idx = 0UL; buf_idx < size_buffer; ++buf_idx) {
+ HAL::mm_memory_fence((VoidPtr) ((UInt8*) ptr + buf_idx));
+ }
+}
+} // namespace Kernel