initial commit

1 files changed, 284 insertions, 0 deletions

diff --git a/src/agb_flash.c b/src/agb_flash.c
new file mode 100644
index 0000000..11e2085
--- /dev/null
+++ b/src/agb_flash.c
@@ -0,0 +1,284 @@
+#include "gba/gba.h"
+#include "gba/flash_internal.h"
+
+static u8 sTimerNum;
+static u16 sTimerCount;
+static vu16 *sTimerReg;
+static u16 sSavedIme;
+
+void SetReadFlash1(u16 *dest);
+
+void SwitchFlashBank(u8 bankNum)
+{
+    FLASH_WRITE(0x5555, 0xAA);
+    FLASH_WRITE(0x2AAA, 0x55);
+    FLASH_WRITE(0x5555, 0xB0);
+    FLASH_WRITE(0x0000, bankNum);
+}
+
+#define DELAY()                  \
+do {                             \
+    vu16 i;                      \
+    for (i = 20000; i != 0; i--) \
+        ;                        \
+} while (0)
+
+u16 ReadFlashId(void)
+{
+    u16 flashId;
+    u16 readFlash1Buffer[0x20];
+    u8 (*readFlash1)(u8 *);
+
+    SetReadFlash1(readFlash1Buffer);
+    readFlash1 = (u8 (*)(u8 *))((s32)readFlash1Buffer + 1);
+
+    // Enter ID mode.
+    FLASH_WRITE(0x5555, 0xAA);
+    FLASH_WRITE(0x2AAA, 0x55);
+    FLASH_WRITE(0x5555, 0x90);
+    DELAY();
+
+    flashId = readFlash1(FLASH_BASE + 1) << 8;
+    flashId |= readFlash1(FLASH_BASE);
+
+    // Leave ID mode.
+    FLASH_WRITE(0x5555, 0xAA);
+    FLASH_WRITE(0x2AAA, 0x55);
+    FLASH_WRITE(0x5555, 0xF0);
+    FLASH_WRITE(0x5555, 0xF0);
+    DELAY();
+
+    return flashId;
+}
+
+void FlashTimerIntr(void)
+{
+    if (sTimerCount != 0 && --sTimerCount == 0)
+        gFlashTimeoutFlag = 1;
+}
+
+u16 SetFlashTimerIntr(u8 timerNum, void (**intrFunc)(void))
+{
+    if (timerNum >= 4)
+        return 1;
+
+    sTimerNum = timerNum;
+    sTimerReg = &REG_TMCNT(sTimerNum);
+    *intrFunc = FlashTimerIntr;
+    return 0;
+}
+
+void StartFlashTimer(u8 phase)
+{
+    const u16 *maxTime = &gFlashMaxTime[phase * 3];
+    sSavedIme = REG_IME;
+    REG_IME = 0;
+    sTimerReg[1] = 0;
+    REG_IE |= (INTR_FLAG_TIMER0 << sTimerNum);
+    gFlashTimeoutFlag = 0;
+    sTimerCount = *maxTime++;
+    *sTimerReg++ = *maxTime++;
+    *sTimerReg-- = *maxTime++;
+    REG_IF = (INTR_FLAG_TIMER0 << sTimerNum);
+    REG_IME = 1;
+}
+
+void StopFlashTimer(void)
+{
+    REG_IME = 0;
+    *sTimerReg++ = 0;
+    *sTimerReg-- = 0;
+    REG_IE &= ~(INTR_FLAG_TIMER0 << sTimerNum);
+    REG_IME = sSavedIme;
+}
+
+u8 ReadFlash1(u8 *addr)
+{
+    return *addr;
+}
+
+void SetReadFlash1(u16 *dest)
+{
+    u16 *src;
+    u16 i;
+
+    PollFlashStatus = (u8 (*)(u8 *))((s32)dest + 1);
+
+    src = (u16 *)ReadFlash1;
+    src = (u16 *)((s32)src & ~1);
+
+    i = ((s32)SetReadFlash1 - (s32)ReadFlash1) >> 1;
+
+    while (i != 0)
+    {
+        *dest++ = *src++;
+        i--;
+    }
+}
+
+void ReadFlash_Core(u8 *src, u8 *dest, u32 size)
+{
+    while (size-- != 0)
+    {
+        *dest++ = *src++;
+    }
+}
+
+void ReadFlash(u16 sectorNum, u32 offset, u8 *dest, u32 size)
+{
+    u8 *src;
+    u16 i;
+    u16 readFlash_Core_Buffer[0x40];
+    u16 *funcSrc;
+    u16 *funcDest;
+    void (*readFlash_Core)(u8 *, u8 *, u32);
+
+    REG_WAITCNT = (REG_WAITCNT & ~WAITCNT_SRAM_MASK) | WAITCNT_SRAM_8;
+
+    if (gFlash->romSize == FLASH_ROM_SIZE_1M)
+    {
+        SwitchFlashBank(sectorNum / SECTORS_PER_BANK);
+        sectorNum %= SECTORS_PER_BANK;
+    }
+
+    funcSrc = (u16 *)ReadFlash_Core;
+    funcSrc = (u16 *)((s32)funcSrc & ~1);
+    funcDest = readFlash_Core_Buffer;
+
+    i = ((s32)ReadFlash - (s32)ReadFlash_Core) >> 1;
+
+    while (i != 0)
+    {
+        *funcDest++ = *funcSrc++;
+        i--;
+    }
+
+    readFlash_Core = (void (*)(u8 *, u8 *, u32))((s32)readFlash_Core_Buffer + 1);
+
+    src = FLASH_BASE + (sectorNum << gFlash->sector.shift) + offset;
+
+    readFlash_Core(src, dest, size);
+}
+
+u32 VerifyFlashSector_Core(u8 *src, u8 *tgt, u32 size)
+{
+    while (size-- != 0)
+    {
+        if (*tgt++ != *src++)
+            return (u32)(tgt - 1);
+    }
+
+    return 0;
+}
+
+u32 VerifyFlashSector(u16 sectorNum, u8 *src)
+{
+    u16 i;
+    u16 verifyFlashSector_Core_Buffer[0x80];
+    u16 *funcSrc;
+    u16 *funcDest;
+    u8 *tgt;
+    u16 size;
+    u32 (*verifyFlashSector_Core)(u8 *, u8 *, u32);
+
+    REG_WAITCNT = (REG_WAITCNT & ~WAITCNT_SRAM_MASK) | WAITCNT_SRAM_8;
+
+    if (gFlash->romSize == FLASH_ROM_SIZE_1M)
+    {
+        SwitchFlashBank(sectorNum / SECTORS_PER_BANK);
+        sectorNum %= SECTORS_PER_BANK;
+    }
+
+    funcSrc = (u16 *)VerifyFlashSector_Core;
+    funcSrc = (u16 *)((s32)funcSrc & ~1);
+    funcDest = verifyFlashSector_Core_Buffer;
+
+    i = ((s32)VerifyFlashSector - (s32)VerifyFlashSector_Core) >> 1;
+
+    while (i != 0)
+    {
+        *funcDest++ = *funcSrc++;
+        i--;
+    }
+
+    verifyFlashSector_Core = (u32 (*)(u8 *, u8 *, u32))((s32)verifyFlashSector_Core_Buffer + 1);
+
+    tgt = FLASH_BASE + (sectorNum << gFlash->sector.shift);
+    size = gFlash->sector.size;
+
+    return verifyFlashSector_Core(src, tgt, size);
+}
+
+u32 VerifyFlashSectorNBytes(u16 sectorNum, u8 *src, u32 n)
+{
+    u16 i;
+    u16 verifyFlashSector_Core_Buffer[0x80];
+    u16 *funcSrc;
+    u16 *funcDest;
+    u8 *tgt;
+    u32 (*verifyFlashSector_Core)(u8 *, u8 *, u32);
+
+    if (gFlash->romSize == FLASH_ROM_SIZE_1M)
+    {
+        SwitchFlashBank(sectorNum / SECTORS_PER_BANK);
+        sectorNum %= SECTORS_PER_BANK;
+    }
+
+    REG_WAITCNT = (REG_WAITCNT & ~WAITCNT_SRAM_MASK) | WAITCNT_SRAM_8;
+
+    funcSrc = (u16 *)VerifyFlashSector_Core;
+    funcSrc = (u16 *)((s32)funcSrc & ~1);
+    funcDest = verifyFlashSector_Core_Buffer;
+
+    i = ((s32)VerifyFlashSector - (s32)VerifyFlashSector_Core) >> 1;
+
+    while (i != 0)
+    {
+        *funcDest++ = *funcSrc++;
+        i--;
+    }
+
+    verifyFlashSector_Core = (u32 (*)(u8 *, u8 *, u32))((s32)verifyFlashSector_Core_Buffer + 1);
+
+    tgt = FLASH_BASE + (sectorNum << gFlash->sector.shift);
+
+    return verifyFlashSector_Core(src, tgt, n);
+}
+
+u32 ProgramFlashSectorAndVerify(u16 sectorNum, u8 *src)
+{
+    u8 i;
+    u32 result;
+
+    for (i = 0; i < 3; i++)
+    {
+        result = ProgramFlashSector(sectorNum, src);
+        if (result != 0)
+            continue;
+
+        result = VerifyFlashSector(sectorNum, src);
+        if (result == 0)
+            break;
+    }
+
+    return result;
+}
+
+u32 ProgramFlashSectorAndVerifyNBytes(u16 sectorNum, u8 *src, u32 n)
+{
+    u8 i;
+    u32 result;
+
+    for (i = 0; i < 3; i++)
+    {
+        result = ProgramFlashSector(sectorNum, src);
+        if (result != 0)
+            continue;
+
+        result = VerifyFlashSectorNBytes(sectorNum, src, n);
+        if (result == 0)
+            break;
+    }
+
+    return result;
+}