From 2969a8bf7a25e00616436b43c7a5e11255f20070 Mon Sep 17 00:00:00 2001
From: Vicki Pfau <vi@endrift.com>
Date: Mon, 27 Jun 2022 21:10:16 -0700
Subject: [PATCH] Core: Fix cache writes that span multiple tiles

---
 include/mgba/core/map-cache.h |  1 +
 src/core/map-cache.c          | 17 +++++++++++++----
 src/gb/renderers/cache-set.c  |  1 +
 src/gba/renderers/cache-set.c |  2 +-
 4 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/include/mgba/core/map-cache.h b/include/mgba/core/map-cache.h
index 2bd5934e8..349fc1663 100644
--- a/include/mgba/core/map-cache.h
+++ b/include/mgba/core/map-cache.h
@@ -23,6 +23,7 @@ DECL_BITS(mMapCacheSystemInfo, TilesWide, 8, 4);
 DECL_BITS(mMapCacheSystemInfo, TilesHigh, 12, 4);
 DECL_BITS(mMapCacheSystemInfo, MacroTileSize, 16, 7);
 DECL_BITS(mMapCacheSystemInfo, MapAlign, 23, 2);
+DECL_BITS(mMapCacheSystemInfo, WriteAlign, 25, 2);
 
 DECL_BITFIELD(mMapCacheEntryFlags, uint16_t);
 DECL_BITS(mMapCacheEntryFlags, PaletteId, 0, 4);
diff --git a/src/core/map-cache.c b/src/core/map-cache.c
index 17df206dd..d51800780 100644
--- a/src/core/map-cache.c
+++ b/src/core/map-cache.c
@@ -70,11 +70,20 @@ void mMapCacheDeinit(struct mMapCache* cache) {
 
 void mMapCacheWriteVRAM(struct mMapCache* cache, uint32_t address) {
 	if (address >= cache->mapStart && address < cache->mapStart + cache->mapSize) {
+		uint32_t align = 1 << (mMapCacheSystemInfoGetWriteAlign(cache->sysConfig) - mMapCacheSystemInfoGetMapAlign(cache->sysConfig));
 		address -= cache->mapStart;
-		struct mMapCacheEntry* status = &cache->status[address >> mMapCacheSystemInfoGetMapAlign(cache->sysConfig)];
-		++status->vramVersion;
-		status->flags = mMapCacheEntryFlagsClearVramClean(status->flags);
-		status->tileStatus[mMapCacheEntryFlagsGetPaletteId(status->flags)].vramClean = 0;
+		address >>= mMapCacheSystemInfoGetMapAlign(cache->sysConfig);
+
+		uint32_t i;
+		for (i = 0; i < align; ++i) {
+			if (address + i >= (cache->mapSize >> mMapCacheSystemInfoGetMapAlign(cache->sysConfig))) {
+				break;
+			}
+			struct mMapCacheEntry* status = &cache->status[address + i];
+			++status->vramVersion;
+			status->flags = mMapCacheEntryFlagsClearVramClean(status->flags);
+			status->tileStatus[mMapCacheEntryFlagsGetPaletteId(status->flags)].vramClean = 0;
+		}
 	}
 }
 
diff --git a/src/gb/renderers/cache-set.c b/src/gb/renderers/cache-set.c
index ebd0d0899..bfc56c2a3 100644
--- a/src/gb/renderers/cache-set.c
+++ b/src/gb/renderers/cache-set.c
@@ -119,6 +119,7 @@ void GBVideoCacheWriteVideoRegister(struct mCacheSet* cache, uint16_t address, u
 	sysconfig = mMapCacheSystemInfoSetMacroTileSize(sysconfig, 5);
 	sysconfig = mMapCacheSystemInfoSetPaletteBPP(sysconfig, 1);
 	sysconfig = mMapCacheSystemInfoSetMapAlign(sysconfig, 0);
+	sysconfig = mMapCacheSystemInfoSetWriteAlign(sysconfig, 0);
 	sysconfig = mMapCacheSystemInfoSetTilesHigh(sysconfig, 5);
 	sysconfig = mMapCacheSystemInfoSetTilesWide(sysconfig, 5);
 	mMapCacheConfigureSystem(map, sysconfig);
diff --git a/src/gba/renderers/cache-set.c b/src/gba/renderers/cache-set.c
index 95093ae9a..51512721d 100644
--- a/src/gba/renderers/cache-set.c
+++ b/src/gba/renderers/cache-set.c
@@ -160,7 +160,7 @@ static void GBAVideoCacheWriteBGCNT(struct mCacheSet* cache, size_t bg, uint16_t
 	int size = GBARegisterBGCNTGetSize(value);
 	int tilesWide = 0;
 	int tilesHigh = 0;
-	mMapCacheSystemInfo sysconfig = 0;
+	mMapCacheSystemInfo sysconfig = mMapCacheSystemInfoSetWriteAlign(0, 1);
 	if (map->mapParser == mapParser0) {
 		map->tileCache = mTileCacheSetGetPointer(&cache->tiles, p);
 		sysconfig = mMapCacheSystemInfoSetPaletteBPP(sysconfig, 2 + p);