OSi_ReadCardRom32

1 files changed, 64 insertions, 0 deletions

diff --git a/arm9/lib/src/OS_reset.c b/arm9/lib/src/OS_reset.c
index 6389fe45..dd3cc073 100644
--- a/arm9/lib/src/OS_reset.c
+++ b/arm9/lib/src/OS_reset.c
@@ -121,4 +121,68 @@ _01FF8284:
     blt _01FF8284
     bx lr
 }
+
+void OSi_ReadCardRom32(u32 src, void *dst, s32 len) //should be static, can't mark as such
+{
+    vu32 *const hdr_GAME_BUF = (vu32 *)(HW_ROM_HEADER_BUF + 0x60);
+
+    enum
+    {
+        CARD_MASTER_SELECT_ROM = 0x0,
+        CARD_MASTER_ENABLE = 0x80,
+        CARD_CMD_READ_PAGE = 0xb7,
+        CARD_CTRL_CMD_MASK = 0x07000000,
+        CARD_CTRL_CMD_PAGE = 0x01000000,
+        CARD_CTRL_READ = 0x00000000,
+        CARD_CTRL_RESET_HI = 0x20000000,
+        CARD_CTRL_START = 0x80000000,
+        CARD_CTRL_READY = 0x00800000,
+        CARD_ENUM_END
+    };
+
+    const u32 ctrl_start = (u32)((*hdr_GAME_BUF &~CARD_CTRL_CMD_MASK)
+                                 | (CARD_CTRL_CMD_PAGE | CARD_CTRL_READ
+                                    | CARD_CTRL_START | CARD_CTRL_RESET_HI));
+
+    s32 pos = -(s32)(src & 511);
+
+    while ((reg_CARD_CNT & CARD_CTRL_START))
+        {}
+    reg_CARD_MASTERCNT = (u32)(CARD_MASTER_SELECT_ROM | CARD_MASTER_ENABLE);
+
+    for (src = (u32)(src + pos); pos < len; src += 512)
+    {
+        (&reg_CARD_CMD)[0] = (u8)(CARD_CMD_READ_PAGE);
+        (&reg_CARD_CMD)[1] = (u8)(src >> 24);
+        (&reg_CARD_CMD)[2] = (u8)(src >> 16);
+        (&reg_CARD_CMD)[3] = (u8)(src >> 8);
+        (&reg_CARD_CMD)[4] = (u8)(src >> 0);
+        (&reg_CARD_CMD)[5] = 0;
+        (&reg_CARD_CMD)[6] = 0;
+        (&reg_CARD_CMD)[7] = 0;
+
+        reg_CARD_CNT = ctrl_start;
+        for (;;)
+        {
+            u32 ctrl = reg_CARD_CNT;
+
+            if ((ctrl & CARD_CTRL_READY))
+            {
+                const u32 data = reg_CARD_DATA;
+
+                if ((pos >= 0) && (pos < len))
+                {
+                    *(u32 *)((u32)dst + pos) = data;
+                }
+
+                pos += sizeof(u32);
+            }
+
+            if (!(ctrl & CARD_CTRL_START))
+            {
+                break;
+            }
+        }
+    }
+}
 #pragma section ITCM end