Kernel/Loader: Grab the system mode from the NCCH ExHeader.

3dsx and elf files default to system mode 2 (96MB allocated to the application).

This allows Home Menu to boot without modifications.
Closes #1849

3 files changed, 27 insertions, 0 deletions

diff --git a/src/core/loader/loader.h b/src/core/loader/loader.h
index 9652d7ac50..e62f77b9c2 100644
--- a/src/core/loader/loader.h
+++ b/src/core/loader/loader.h
@@ -96,6 +96,17 @@ public:
     virtual ResultStatus Load() = 0;
 
     /**
+     * Loads the system mode that this application needs.
+     * This function defaults to 2 (96MB allocated to the application) if it can't read the information.
+     * @param system_mode Out variable where the system mode will be stored.
+     * @returns ResultStatus result of the operation
+     */
+    virtual ResultStatus LoadKernelSystemMode(u32& system_mode) {
+        system_mode = 2; // 96MB allocated to the application.
+        return ResultStatus::Success;
+    }
+
+    /**
      * Get the code (typically .code section) of the application
      * @param buffer Reference to buffer to store data
      * @return ResultStatus result of function
diff --git a/src/core/loader/ncch.cpp b/src/core/loader/ncch.cpp
index fadd7b16b1..6fbaf4036c 100644
--- a/src/core/loader/ncch.cpp
+++ b/src/core/loader/ncch.cpp
@@ -117,6 +117,14 @@ FileType AppLoader_NCCH::IdentifyType(FileUtil::IOFile& file) {
     return FileType::Error;
 }
 
+ResultStatus AppLoader_NCCH::LoadKernelSystemMode(u32& memory_type) {
+    ResultStatus result = LoadExeFS();
+    if (result != ResultStatus::Success)
+        return result;
+    memory_type = exheader_header.arm11_system_local_caps.system_mode;
+    return ResultStatus::Success;
+}
+
 ResultStatus AppLoader_NCCH::LoadExec() {
     using Kernel::SharedPtr;
     using Kernel::CodeSet;
@@ -277,6 +285,7 @@ ResultStatus AppLoader_NCCH::LoadExeFS() {
     LOG_DEBUG(Loader, "Core version:                %d", core_version);
     LOG_DEBUG(Loader, "Thread priority:             0x%X", priority);
     LOG_DEBUG(Loader, "Resource limit category:     %d", resource_limit_category);
+    LOG_DEBUG(Loader, "System Mode:                 %d", exheader_header.arm11_system_local_caps.system_mode);
 
     if (exheader_header.arm11_system_local_caps.program_id != ncch_header.program_id) {
         LOG_ERROR(Loader, "ExHeader Program ID mismatch: the ROM is probably encrypted.");
diff --git a/src/core/loader/ncch.h b/src/core/loader/ncch.h
index f8718d0639..63947c28ee 100644
--- a/src/core/loader/ncch.h
+++ b/src/core/loader/ncch.h
@@ -186,6 +186,13 @@ public:
     ResultStatus Load() override;
 
     /**
+     * Loads the Exheader and returns the system mode for this application.
+     * @param system_mode Out variable where the system mode will be stored.
+     * @return ResultStatus result of the operation
+     */
+    ResultStatus LoadKernelSystemMode(u32& system_mode);
+
+    /**
      * Get the code (typically .code section) of the application
      * @param buffer Reference to buffer to store data
      * @return ResultStatus result of function