From 9a35691a03d1dc9250208f2a7ab8cdc7fb8bf2aa Mon Sep 17 00:00:00 2001
From: Vicki Pfau <vi@endrift.com>
Date: Wed, 12 Apr 2017 00:54:32 -0700
Subject: [PATCH] DS: Attempt to detect if a game is homebrew

---
 CHANGES                       |  1 +
 include/mgba/internal/ds/ds.h | 11 +++++++++++
 src/ds/ds.c                   |  4 ++++
 3 files changed, 16 insertions(+)

diff --git a/CHANGES b/CHANGES
index 5a4618c24..2f4241d6e 100644
--- a/CHANGES
+++ b/CHANGES
@@ -17,6 +17,7 @@ Misc:
  - ARM9: Implement SMLAW<y> and SMULW<y>
  - Qt: Add .nds files to the extension list in Info.plist
  - ARM9: Implement STRD/LDRD
+ - DS: Attempt to detect if a game is homebrew
 
 0.6.0: (Future)
 Features:
diff --git a/include/mgba/internal/ds/ds.h b/include/mgba/internal/ds/ds.h
index 1f95a161f..baa2b4a17 100644
--- a/include/mgba/internal/ds/ds.h
+++ b/include/mgba/internal/ds/ds.h
@@ -123,6 +123,8 @@ struct DS {
 
 	struct mTimingEvent divEvent;
 	struct mTimingEvent sqrtEvent;
+
+	bool isHomebrew;
 };
 
 struct DSCartridge {
@@ -158,6 +160,15 @@ struct DSCartridge {
 	uint32_t iconOffset;
 	uint16_t secureAreaCrc16;
 	uint16_t secureAreaDelay;
+	uint32_t arm9Autoload;
+	uint32_t arm7Autoload;
+	uint8_t secureAreaDisable[8];
+	uint32_t usedSize;
+	uint32_t romHeaderSize;
+	uint8_t reserved2[56];
+	uint8_t logo[156];
+	uint16_t logoCrc16;
+	uint16_t headerCrc16;
 	// TODO: Fill in more
 	// And ROM data...
 };
diff --git a/src/ds/ds.c b/src/ds/ds.c
index c64af2100..4409d3575 100644
--- a/src/ds/ds.c
+++ b/src/ds/ds.c
@@ -294,6 +294,7 @@ void DS7Reset(struct ARMCore* cpu) {
 	DS7IOInit(ds);
 
 	DSConfigureWRAM(&ds->memory, 3);
+	ds->isHomebrew = false;
 
 	struct DSCartridge* header = ds->romVf->map(ds->romVf, sizeof(*header), MAP_READ);
 	if (header) {
@@ -304,6 +305,9 @@ void DS7Reset(struct ARMCore* cpu) {
 		ds->memory.ram[0x3FFC40 >> 2] = 1;
 		memcpy(&ds->memory.ram[0x3FFE00 >> 2], header, 0x170);
 		DS7IOWrite32(ds, DS_REG_ROMCNT_LO, header->busTiming | 0x2700000);
+
+		ds->isHomebrew = memcmp(&header->logoCrc16, DS_ROM_MAGIC, sizeof(header->logoCrc16));
+
 		// TODO: Error check
 		ds->romVf->seek(ds->romVf, header->arm7Offset, SEEK_SET);
 		uint32_t base = header->arm7Base;