1 files changed, 103 insertions, 0 deletions
diff --git a/kernel/src/acpi/manager.cpp b/kernel/src/acpi/manager.cpp
new file mode 100644
index 0000000..300b85e
--- /dev/null
+++ b/kernel/src/acpi/manager.cpp
@@ -0,0 +1,103 @@
+#include "kernel/acpi/manager.hpp"
+
+#include "kapi/acpi.hpp"
+#include "kapi/memory.hpp"
+#include "kapi/system.hpp"
+
+#include <kstd/memory>
+#include <kstd/print>
+
+#include <cstddef>
+#include <cstdint>
+#include <string_view>
+
+namespace kernel::acpi
+{
+
+  manager::manager(kapi::acpi::root_system_description_pointer const & sdp)
+      : m_sdp{&sdp}
+  {
+    if (m_sdp->signature() != "RSD PTR ")
+    {
+      kapi::system::panic("[OS:ACPI] Invalid RSDP signature!");
+    }
+
+    if (m_sdp->revision() >= 2)
+    {
+      auto const xsdp = static_cast<kapi::acpi::extended_system_description_pointer const *>(m_sdp);
+      if (!xsdp->validate())
+      {
+        kapi::system::panic("[OS:ACPI] Invalid XSDP signature!");
+      }
+      auto physical_extended_table_address = xsdp->table_address();
+      auto linear_extended_table_address = kapi::memory::hhdm_to_linear(physical_extended_table_address);
+      m_rsdt = static_cast<kapi::acpi::system_description_table_header const *>(linear_extended_table_address);
+      m_extended = true;
+    }
+    else
+    {
+      if (!m_sdp->validate())
+      {
+        kapi::system::panic("[OS:ACPI] Invalid RSDP checksum!");
+      }
+      auto physical_root_table_address = m_sdp->table_address();
+      auto linear_root_table_address = kapi::memory::hhdm_to_linear(physical_root_table_address);
+      m_rsdt = static_cast<kapi::acpi::system_description_table_header const *>(linear_root_table_address);
+    }
+  }
+
+  auto manager::load_tables() -> bool
+  {
+    if (!kapi::acpi::validate_checksum({reinterpret_cast<std::byte const *>(m_rsdt), m_rsdt->length().value}))
+    {
+      kapi::system::panic("[OS:ACPI] Invalid RSDT checksum!");
+    }
+
+    auto entry_size = m_extended ? sizeof(std::uint64_t) : sizeof(std::uint32_t);
+    auto entry_count = (m_rsdt->length().value - sizeof(kapi::acpi::system_description_table_header)) / entry_size;
+    auto entries_base =
+        reinterpret_cast<std::byte const *>(m_rsdt) + sizeof(kapi::acpi::system_description_table_header);
+
+    for (std::size_t i = 0; i < entry_count; ++i)
+    {
+      auto physical_table_address = kapi::memory::physical_address{};
+
+      if (m_extended)
+      {
+        auto entry = reinterpret_cast<std::uint64_t const *>(entries_base + (i * entry_size));
+        physical_table_address = kapi::memory::physical_address{*entry};
+      }
+      else
+      {
+        auto entry = reinterpret_cast<std::uint32_t const *>(entries_base + (i * entry_size));
+        physical_table_address = kapi::memory::physical_address{*entry};
+      }
+
+      auto linear_table_address = kapi::memory::hhdm_to_linear(physical_table_address);
+      auto table = static_cast<kapi::acpi::system_description_table_header const *>(linear_table_address);
+
+      if (!kapi::acpi::validate_checksum({reinterpret_cast<std::byte const *>(table), table->length().value}))
+      {
+        kstd::println(kstd::print_sink::stderr, "[OS:ACPI] Invalid table checksum!");
+      }
+      else
+      {
+        kstd::println("[OS:ACPI] Found '{}' ACPI table", table->signature());
+        m_tables.emplace(table->signature(), table);
+      }
+    }
+
+    return !m_tables.empty();
+  }
+
+  auto manager::get_table(std::string_view signature)
+      -> kstd::observer_ptr<kapi::acpi::system_description_table_header const>
+  {
+    if (m_tables.contains(signature))
+    {
+      return kstd::make_observer(m_tables.at(signature));
+    }
+    return nullptr;
+  }
+
+}  // namespace kernel::acpi