exo: implement start of mariko fatal handler

exosphere/mariko_fatal/source/fatal_sdmmc.cpp

@@ -0,0 +1,50 @@
+/*
+ * 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 <exosphere.hpp>
+#include "fatal_device_page_table.hpp"
+
+namespace ams::secmon::fatal {
+
+    namespace {
+
+        constexpr inline auto Port = sdmmc::Port_SdCard0;
+
+        ALWAYS_INLINE u8 *GetSdCardWorkBuffer() {
+            return MemoryRegionVirtualDramSdmmcMappedData.GetPointer<u8>() + MemoryRegionVirtualDramSdmmcMappedData.GetSize() - mmu::PageSize;
+        }
+
+    }
+
+    Result InitializeSdCard() {
+        /* Map main memory for the sdmmc device. */
+        AMS_SECMON_LOG("%s\n", "Initializing Device Page Table.");
+        InitializeDevicePageTableForSdmmc1();
+        AMS_SECMON_LOG("%s\n", "Initialized Device Page Table.");
+
+        /* Initialize sdmmc library. */
+        sdmmc::Initialize(Port);
+        AMS_SECMON_LOG("%s\n", "Initialized Sdmmc Port.");
+
+        sdmmc::SetSdCardWorkBuffer(Port, GetSdCardWorkBuffer(), sdmmc::SdCardWorkBufferSize);
+        AMS_SECMON_LOG("%s\n", "Set SD Card Work Buffer.");
+
+        R_TRY(sdmmc::Activate(Port));
+        AMS_SECMON_LOG("%s\n", "Activated.");
+
+        return ResultSuccess();
+    }
+
+}