Add hardware abstraction layer.

include/hal/hal.h

@@ -0,0 +1,23 @@
+#ifndef HAL_HAL
+#define HAL_HAL
+
+#include <stdbigos/address.h>
+#include <stdbigos/error.h>
+
+/// @addtogroup hal
+/// @{
+
+/**
+ * @param dtb Physical address of device tree blob
+ * @param physical_to_effective A pointer to a function that transalates physical addresses into effective ones
+ *
+ * @retval ERR_NONE Success
+ * @retval ERR_BAD_ARG @p dtb is null
+ * @retval ERR_NOT_VALID No valid device tree found at address @p dtb
+ * */
+[[gnu::nonnull(2)]]
+error_t hal_init(__phys void* dtb, void* (*physical_to_effective)(__phys void*));
+
+/// @}
+
+#endif // !HAL_HAL

include/hal/memory_regions.h

@@ -0,0 +1,30 @@
+#ifndef HAL_MEMORY_REGIONS
+#define HAL_MEMORY_REGIONS
+
+#include <stdbigos/error.h>
+#include <stdbigos/memory_types.h>
+
+/**
+ * This type is opaque to the caller.
+ * Fields of this struct should not be modified directly.
+ * */
+typedef struct {
+	u32 idx;
+	bool in_memresblock;
+} hal_reserved_iterator_t;
+
+error_t hal_get_reserved_regions_iterator(hal_reserved_iterator_t* iterOUT);
+error_t hal_get_next_reserved_region(hal_reserved_iterator_t iter, memory_area_t* areaOUT);
+
+/**
+ * This type is opaque to the caller.
+ * Fields of this struct should not be modified directly.
+ * */
+typedef struct {
+	u32 idx;
+} hal_memory_iterator_t;
+
+error_t hal_get_memory_regions_iterator(hal_memory_iterator_t* iterOUT);
+error_t hal_get_next_memory_region(hal_memory_iterator_t iter, memory_area_t* areaOUT);
+
+#endif // !HAL_MEMORY_REGIONS

include/stdbigos/error.h

@@ -16,6 +16,7 @@ typedef enum [[nodiscard]] {
 	ERR_OUT_OF_MEMORY,
 	ERR_NOT_ENOUGH_MEMORY,
 	ERR_REPEATED_INITIALIZATION,
+	ERR_ALLOCATION_FAILED,
 } error_t;
 
 #endif // !BIGOS_INCLUDE_STDBIGOS_ERROR

src/kernel/CMakeLists.txt

@@ -1,6 +1,7 @@
 SETUP_EXECUTABLE(kernel)
 
 target_compile_definitions(kernel PRIVATE $<IF:$<CONFIG:DEBUG>,__DEBUG__ __LOGLVL__=3, __LOGLVL__=1>)
+target_compile_definitions(kernel PRIVATE __ARCH_RISCV__) # Make this an opt when we add support for other arches
 target_link_libraries(kernel PRIVATE Debug stdbigos)
 
 target_link_options(kernel PRIVATE -static-pie -e kinit)

src/lib/hal/CMakeLists.txt

@@ -0,0 +1,7 @@
+SETUP_LIBRARY(hal)
+
+target_link_libraries(hal
+    PUBLIC stdbigos
+    PRIVATE Debug
+    PRIVATE device_tree_access
+)

src/lib/hal/hal.c

@@ -0,0 +1,38 @@
+#include <hal/hal.h>
+
+#include "dt/dt.h"
+
+//===========
+// Internals
+//===========
+
+static bool g_is_init = false;
+static __phys void* g_dtb = nullptr;
+static void* (*g_physical_to_effective)(__phys void*) = nullptr;
+
+bool ihal_is_init() {
+	return g_is_init;
+}
+
+error_t ihal_get_dtb(void** dtbOUT) {
+	if (!g_is_init)
+		return ERR_NOT_INITIALIZED;
+	*dtbOUT = g_physical_to_effective(g_dtb);
+	return ERR_NONE;
+}
+
+//========
+// Public
+//========
+
+error_t hal_init(__phys void* dtb, void* (*physical_to_effective)(__phys void*)) {
+	if (dtb == nullptr)
+		return ERR_BAD_ARG;
+	fdt_t fdt = {0};
+	error_t err = dt_init(physical_to_effective(dtb), &fdt);
+	if (err)
+		return err;
+	g_physical_to_effective = physical_to_effective;
+	g_is_init = true;
+	return ERR_NONE;
+}

src/lib/hal/hal_internal.h

@@ -0,0 +1,4 @@
+#ifndef LIB_HAL_HAL_INTERNAL
+#define LIB_HAL_HAL_INTERNAL
+
+#endif // !LIB_HAL_HAL_INTERNAL

src/lib/hal/memory_region.c

@@ -0,0 +1,24 @@
+#include <hal/memory_regions.h>
+#include <stdbigos/error.h>
+
+error_t hal_get_reserved_regions_iterator(hal_reserved_iterator_t* iterOUT) {
+	(void)iterOUT;
+	return ERR_NOT_INITIALIZED;
+}
+
+error_t hal_get_next_reserved_region(hal_reserved_iterator_t iter, memory_area_t* areaOUT) {
+	(void)iter;
+	(void)areaOUT;
+	return ERR_NOT_INITIALIZED;
+}
+
+error_t hal_get_memory_regions_iterator(hal_memory_iterator_t* iterOUT) {
+	(void)iterOUT;
+	return ERR_NOT_INITIALIZED;
+}
+
+error_t hal_get_next_memory_region(hal_memory_iterator_t iter, memory_area_t* areaOUT) {
+	(void)iter;
+	(void)areaOUT;
+	return ERR_NOT_INITIALIZED;
+}