LEGO Indiana Jones

[savezelda.git] / twilight / twilight.c

diff --git a/twilight/twilight.c b/twilight/twilight.c
new file mode 100644 (file)
index 0000000..9ce9a2b
--- /dev/null
+++ b/twilight/twilight.c
@@ -0,0 +1,222 @@
+// Copyright 2008-2009  Segher Boessenkool  <segher@kernel.crashing.org>
+// This code is licensed to you under the terms of the GNU GPL, version 2;
+// see file COPYING or http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt
+
+#undef DEBUG_GECKO
+#undef DEBUG_BLINK
+
+typedef unsigned int u32;
+typedef unsigned char u8;
+
+int nand_open_E0(const char *path, void *buf, u32 mode);
+int nand_open_E2(const char *path, void *buf, u32 mode);
+int nand_open_J0(const char *path, void *buf, u32 mode);
+int nand_open_P0(const char *path, void *buf, u32 mode);
+
+int nand_read_E0(void *buf, void *dest, u32 len);
+int nand_read_E2(void *buf, void *dest, u32 len);
+int nand_read_J0(void *buf, void *dest, u32 len);
+int nand_read_P0(void *buf, void *dest, u32 len);
+
+void audio_stop_E0(void);
+void audio_stop_E2(void);
+void audio_stop_J0(void);
+void audio_stop_P0(void);
+
+void graphics_stop_E0(void);
+void graphics_stop_E2(void);
+void graphics_stop_J0(void);
+void graphics_stop_P0(void);
+
+static u8 nand_buf[0x100] __attribute__ ((aligned(0x40)));
+
+#ifdef DEBUG_GECKO
+void gecko_print(void *, const char *);
+
+#define PRINT(x) gecko_print(0, x)
+#define HEX(x) hex(x)
+
+static void hex(u32 x)
+{
+       u32 i;
+       u32 digit;
+       char s[10];
+
+       for (i = 0; i < 8; i++) {
+               digit = x >> 28;
+               x <<= 4;
+               s[i] = digit + '0' + (digit < 10 ? 0 : 'a' - 10 - '0');
+       }
+       s[8] = '\n';
+       s[9] = 0;
+       PRINT(s);
+}
+#else
+#define PRINT(x) do { } while (0)
+#define HEX(x) do { } while (0)
+#endif
+
+static void sync_cache(void *p, u32 n)
+{
+       u32 start, end;
+
+       start = (u32)p & ~31;
+       end = ((u32)p + n + 31) & ~31;
+       n = (end - start) >> 5;
+
+       while (n--) {
+               asm("dcbst 0,%0 ; icbi 0,%0" : : "b"(p));
+               p += 32;
+       }
+       asm("sync ; isync");
+}
+
+static void sync_before_read(void *p, u32 n)
+{
+       u32 start, end;
+
+       start = (u32)p & ~31;
+       end = ((u32)p + n + 31) & ~31;
+       n = (end - start) >> 5;
+
+       while (n--) {
+               asm("dcbf 0,%0" : : "b"(p));
+               p += 32;
+       }
+       asm("sync");
+}
+
+static void jump(void *p, u32 arg)
+{
+       PRINT("taking the plunge...\n");
+
+       asm("mr 3,%1 ; mtctr %0 ; bctrl" : : "r"(p), "r"(arg) : "r3");
+
+       PRINT("whoops, payload returned to us\n");
+}
+
+#ifdef DEBUG_BLINK
+static u32 read32(u32 addr)
+{
+       u32 x;
+
+       asm volatile("lwz %0,0(%1) ; sync" : "=r"(x) : "b"(0xc0000000 | addr));
+
+       return x;
+}
+
+static void write32(u32 addr, u32 x)
+{
+       asm("stw %0,0(%1) ; eieio" : : "r"(x), "b"(0xc0000000 | addr));
+}
+
+static void blink(u32 colour)
+{
+       u32 *fb = (u32 *)0xC0F00000;
+       u32 i;
+
+       // blink tray led
+       write32(0x0d8000c0, read32(0x0d8000c0) ^ 0x20);
+
+       for (i = 0; i < 640*576/2; i++)
+               fb[i] = colour;
+}
+#else
+#define blink(x) do { } while(0)
+#endif
+
+void __attribute__ ((noreturn)) main(u32 baddr)
+{
+       int ret, i, len;
+       char *area;
+       char *gameid = (char *)0x80000000;
+       int (*nand_open)(const char *path, void *buf, u32 mode);
+       int (*nand_read)(void *buf, void *dest, u32 len);
+       void (*audio_stop)(void);
+       void (*graphics_stop)(void);
+
+       PRINT("Hello, Brave New World!\n");
+
+       baddr -= 0x2c0;
+
+       switch (gameid[3]) {
+       case 'E':
+               if ((baddr>>16) == 0x8045) {
+                       nand_open = nand_open_E2;
+                       nand_read = nand_read_E2;
+                       audio_stop = audio_stop_E2;
+                       graphics_stop = graphics_stop_E2;
+               } else {
+                       nand_open = nand_open_E0;
+                       nand_read = nand_read_E0;
+                       audio_stop = audio_stop_E0;
+                       graphics_stop = graphics_stop_E0;
+               }
+               break;
+       case 'P':
+               nand_open = nand_open_P0;
+               nand_read = nand_read_P0;
+               audio_stop = audio_stop_P0;
+               graphics_stop = graphics_stop_P0;
+               break;
+       case 'J':
+               nand_open = nand_open_J0;
+               nand_read = nand_read_J0;
+               audio_stop = audio_stop_J0;
+               graphics_stop = graphics_stop_J0;
+               break;
+       default:
+               PRINT("unsupported game region\n");
+               for (;;)
+                       ;
+       }
+
+       audio_stop();
+       graphics_stop();
+
+       blink(0x266a26c0); // maroon
+
+       ret = nand_open("zeldaTp.dat", nand_buf, 1);
+
+       blink(0x7140718a); // olive
+
+       PRINT("nand open --> ");
+       HEX(ret);
+
+       area = (void *)0x90000020;
+
+       // Skip past save game, to loader.bin
+       ret = nand_read(nand_buf, area, 0x4000);
+
+       len = 0;
+       for (i = 0; i < 0x40; i++) {
+               PRINT("reading bootloader page: ");
+               HEX(i);
+
+               blink(0x40804080 + i*0x02000200); // grey
+
+               sync_before_read(area + 0x1000*i, 0x1000);
+               ret = nand_read(nand_buf, area + 0x1000*i, 0x1000);
+               len += ret;
+
+               blink(0x552b5515 + i*0x02000200); // lime
+
+               PRINT("--> ");
+               HEX(ret);
+               PRINT("\n");
+       }
+
+       for (i = 0; i < 0x100; i++)
+               HEX(((u32 *)area)[i]);
+
+       blink(0xc399c36a); // sky blue
+
+       sync_cache(area, len);
+       jump(area, 0x123);
+
+       blink(0x4c544cff); // red
+
+       PRINT("(shouldn't happen)\n");
+       for (;;)
+               ;
+}