YAWM-ModMii-Edition/source/otp.c
2024-04-22 08:06:01 -05:00

68 lines
1.9 KiB
C

#include <ogc/machine/processor.h>
#include <unistd.h>
#include <string.h>
#include "otp.h"
#define HW_OTP_COMMAND (*(vu32*)0xCD8001EC)
#define HW_OTP_DATA (*(vu32*)0xCD8001F0)
#define HW_OTP_BLK_SIZE 4
#define HW_OTP_BLK_CNT (OTP_SIZE / HW_OTP_BLK_SIZE)
u8 otp_read(void *dst, u8 offset, u8 size)
{
if (!dst || offset >= OTP_SIZE || !size || (offset + size) > OTP_SIZE) return 0;
u8 cur_offset = 0;
u8 *ptr = (u8*)dst;
u8 val[HW_OTP_BLK_SIZE] = {0};
// Calculate block offsets and sizes
u8 start_addr = (offset / HW_OTP_BLK_SIZE);
u8 start_addr_offset = (offset % HW_OTP_BLK_SIZE);
u8 end_addr = ((offset + size) / HW_OTP_BLK_SIZE);
u8 end_addr_size = ((offset + size) % HW_OTP_BLK_SIZE);
if (!end_addr_size)
{
end_addr--;
end_addr_size = HW_OTP_BLK_SIZE;
}
if (end_addr == start_addr) end_addr_size -= start_addr_offset;
for(u8 i = start_addr; i <= end_addr; i++)
{
if (cur_offset >= size) break;
// Send command + address
HW_OTP_COMMAND = (0x80000000 | i);
// Receive data
*((u32*)val) = HW_OTP_DATA;
// Copy read data to destination buffer
if (i == start_addr && start_addr_offset != 0)
{
// Handle unaligned read at start address
memcpy(ptr + cur_offset, val + start_addr_offset, HW_OTP_BLK_SIZE - start_addr_offset);
cur_offset += (HW_OTP_BLK_SIZE - start_addr_offset);
} else
if (i == end_addr && end_addr_size != HW_OTP_BLK_SIZE)
{
// Handle unaligned read at end address
memcpy(ptr + cur_offset, val, end_addr_size);
cur_offset += end_addr_size;
} else {
// Normal read
memcpy(ptr + cur_offset, val, HW_OTP_BLK_SIZE);
cur_offset += HW_OTP_BLK_SIZE;
}
}
return cur_offset;
}