kern: begin skeletoning page table types

libraries/libmesosphere/source/arch/arm64/kern_k_page_table.cpp

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2018-2020 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <mesosphere.hpp>
+
+namespace ams::kern::arm64 {
+
+    void KPageTable::Initialize(s32 core_id) {
+        /* Nothing actually needed here. */
+    }
+
+    Result KPageTable::InitializeForKernel(void *table, KVirtualAddress start, KVirtualAddress end) {
+        /* Initialize basic fields. */
+        this->asid = 0;
+        this->manager = std::addressof(Kernel::GetPageTableManager());
+
+        /* Allocate a page for ttbr. */
+        const u64 asid_tag = (static_cast<u64>(this->asid) << 48ul);
+        const KVirtualAddress page = this->manager->Allocate();
+        MESOSPHERE_ASSERT(page != Null<KVirtualAddress>);
+        cpu::ClearPageToZero(GetVoidPointer(page));
+        this->ttbr = GetInteger(KPageTableBase::GetLinearPhysicalAddress(page)) | asid_tag;
+
+        /* Initialize the base page table. */
+        MESOSPHERE_R_ABORT_UNLESS(KPageTableBase::InitializeForKernel(true, table, start, end));
+
+        return ResultSuccess();
+    }
+
+    Result KPageTable::Finalize() {
+        MESOSPHERE_TODO_IMPLEMENT();
+    }
+}