我正在尝试使用 C 语言中的 Linux MTD 驱动程序擦除 NOR 闪存...
我对ioctl(MEMUNLOCK)调用的返回状态感到困惑，即使ioctl(MEMERASE)在它之后成功也会返回错误。
以下代码显示警告消息但有效（即闪存块已被擦除）：
int erase_MTD_Pages(int fd, size_t size, off_t offset)
{
mtd_info_t mtd_info;
erase_info_t ei;
ioctl(fd, MEMGETINFO, &mtd_info);
ei.length = mtd_info.erasesize;
for(ei.start = offset; ei.start < (offset+size); ei.start += mtd_info.erasesize) {
if(ioctl(fd, MEMUNLOCK, &ei) < 0)
{
// logPrintf(FAILURE, "[Flash] Can not unlock MTD (MEMUNLOCK, errno=%d)!\n", errno);
// return RETURN_FILE_ERROR;
logPrintf(WARNING, "[Flash] Can not unlock MTD (MEMUNLOCK, errno=%d)!\n", errno);
}
if(ioctl(fd, MEMERASE, &ei) < 0)
{
logPrintf(FAILURE, "[Flash] Can not erase MTD (MEMERASE, errno=%d)!\n", errno);
return RETURN_FILE_ERROR;
}
}
return RETURN_SUCCESS;
}
当我在网上查看一些 C 代码时，并不总是检查 MEMUNLOCK 的返回状态（例如来自mtc.c）：
ioctl(fd, MEMUNLOCK, &mtdEraseInfo);
if(ioctl(fd, MEMERASE, &mtdEraseInfo)) {
fprintf(stderr, "Could not erase MTD device: %s\n", mtd);
close(fd);
exit(1);
}
flash_unlock也返回一个错误：
root $ cat /proc/mtd
dev: size erasesize name
mtd0: 00020000 00020000 "X-Loader-NOR"
mtd1: 000a0000 00020000 "U-Boot-NOR"
mtd2: 00040000 00020000 "Boot Env-NOR"
mtd3: 00400000 00020000 "Kernel-NOR"
mtd4: 03b00000 00020000 "File System-NOR"
root $ mtd_debug info /dev/mtd3
mtd.type = MTD_NORFLASH
mtd.flags = MTD_CAP_NORFLASH
mtd.size = 4194304 (4M)
mtd.erasesize = 131072 (128K)
mtd.writesize = 1
mtd.oobsize = 0
regions = 0
root $ flash_unlock /dev/mtd3
Could not unlock MTD device: /dev/mtd3
我错过了什么吗？使用某些配置从 MEMUNLOCK 收到错误是否正常？
备注/环境：
- 未在
mtd3分区上设置只读标志 (MTD_WRITEABLE) （仅在mtd0和上mtd1）。 flash_lock也返回相同的错误。- TI AM3505（ARM Cortex A8、OMAP34）。
- Linux 2.6.37。
- 闪存 NOR Spansion S29GL512S12DHIV1。
内核日志：
mtdoops: mtd device (mtddev=name/number) must be supplied
physmap platform flash device: 08000000 at 08000000
physmap-flash.0: Found 1 x16 devices at 0x0 in 16-bit bank. Manufacturer ID 0x000001 Chip ID 0x002301
Amd/Fujitsu Extended Query Table at 0x0040
Amd/Fujitsu Extended Query version 1.5.
Silicon revision: 14
Address sensitive unlock: Required
Erase Suspend: Read/write
Block protection: 1 sectors per group
Temporary block unprotect: Not supported
Block protect/unprotect scheme: 8
Number of simultaneous operations: 0
Burst mode: Not supported
Page mode: 12 word page
Vpp Supply Minimum Program/Erase Voltage: 0.0 V
Vpp Supply Maximum Program/Erase Voltage: 0.0 V
Top/Bottom Boot Block: Uniform, Top WP
number of CFI chips: 1
RedBoot partition parsing not available
Using physmap partition information
Creating 5 MTD partitions on "physmap-flash.0":
0x000000000000-0x000000020000 : "X-Loader-NOR"
0x000000020000-0x0000000c0000 : "U-Boot-NOR"
0x0000000c0000-0x000000100000 : "Boot Env-NOR"
0x000000100000-0x000000500000 : "Kernel-NOR"
0x000000500000-0x000004000000 : "File System-NOR"