想给和家亲摄像头刷 OpenIPC，求助 u-boot 相关问题

纯小白，不太了解这方面，让大家见笑了。

摄像头是岭雁科技的 LYC40-PTZ ，经拆机确认 SoC 是君正的 T31N ，CMOS 是 sc2335 ，应该可以支持 OpenIPC ，所以用 ttl 连接后按照网上一些教程照葫芦画瓢准备进 u-boot 刷机。

启动日志如下：

U-Boot SPL 2013.07 (Nov 23 2020 - 17:19:58)
Timer init
CLK stop
PLL init
pll_init:366
pll_cfg.pdiv = 10, pll_cfg.h2div = 5, pll_cfg.h0div = 5, pll_cfg.cdiv = 1, pll_cfg.l2div = 2
nf=118 nr = 1 od0 = 1 od1 = 2
cppcr is 07605100
CPM_CPAPCR 0750510d
nf=100 nr = 1 od0 = 1 od1 = 2
cppcr is 06405100
CPM_CPMPCR 0640510d
nf=100 nr = 1 od0 = 1 od1 = 2
cppcr is 06405100
CPM_CPVPCR 0640510d
cppcr 0x9a7b5510
apll_freq 1404000000
mpll_freq 1200000000
vpll_freq = 1200000000
ddr sel mpll, cpu sel apll
ddrfreq 600000000
cclk  1404000000
l2clk 702000000
h0clk 240000000
h2clk 240000000
pclk  120000000
CLK init
SDRAM init
sdram init start
ddr_inno_phy_init ..!
phy reg = 0x00000007, CL = 0x00000007
ddr_inno_phy_init ..! 11:  00000004
ddr_inno_phy_init ..! 22:  00000006
ddr_inno_phy_init ..! 33:  00000006
REG_DDR_LMR: 00000210
REG_DDR_LMR: 00000310
REG_DDR_LMR: 00000110
REG_DDR_LMR, MR0: 00f73011
T31_0x5: 00000007
T31_0x15: 0000000c
T31_0x4: 00000000
T31_0x14: 00000002
INNO_TRAINING_CTRL 1: 00000000
INNO_TRAINING_CTRL 2: 000000a1
T31_cc: 00000003
INNO_TRAINING_CTRL 3: 000000a0
T31_118: 0000003c
T31_158: 0000003c
T31_190: 0000001f
T31_194: 0000001e
jz-04 :  0x00000051
jz-08 :  0x000000a0
jz-28 :  0x00000024
DDR PHY init OK
INNO_DQ_WIDTH   :00000003
INNO_PLL_FBDIV  :00000014
INNO_PLL_PDIV   :00000005
INNO_MEM_CFG    :00000051
INNO_PLL_CTRL   :00000018
INNO_CHANNEL_EN :0000000d
INNO_CWL        :00000006
INNO_CL         :00000007
DDR Controller init
DDRC_STATUS         0x80000001
DDRC_CFG            0x0a288a40
DDRC_CTRL           0x0000011c
DDRC_LMR            0x00400008
DDRC_DLP            0x00000000
DDRC_TIMING1        0x040e0806
DDRC_TIMING2        0x02170707
DDRC_TIMING3        0x2007051e
DDRC_TIMING4        0x1a240031
DDRC_TIMING5        0xff060405
DDRC_TIMING6        0x32170505
DDRC_REFCNT         0x00f2e701
DDRC_MMAP0          0x000020fc
DDRC_MMAP1          0x00002400
DDRC_REMAP1         0x03020d0c
DDRC_REMAP2         0x07060504
DDRC_REMAP3         0x0b0a0908
DDRC_REMAP4         0x0f0e0100
DDRC_REMAP5         0x13121110
DDRC_AUTOSR_EN      0x00000000
sdram init finished
SDRAM init ok
board_init_r
image entry point: 0x80100000


U-Boot 2013.07 (Nov 23 2020 - 17:19:58)

Board: ISVP (Ingenic XBurst T31 SoC)
DRAM:  64 MiB
Top of RAM usable for U-Boot at: 84000000
Reserving 445k for U-Boot at: 83f90000
Reserving 32832k for malloc() at: 81f80000
Reserving 32 Bytes for Board Info at: 81f7ffe0
Reserving 124 Bytes for Global Data at: 81f7ff64
Reserving 128k for boot params() at: 81f5ff64
Stack Pointer at: 81f5ff48
Now running in RAM - U-Boot at: 83f90000
MMC:   msc: 0
the manufacturer 1c
SF: Detected EN25QH128A

In:    serial
Out:   serial
Err:   serial
Net:   ====>phy 0:0x0-0x0 found
SPEED:0, DUPLEX:0
Jz4775-9161
upgradeFirmware 20200921120000 20200921120000
upgradeFirmware 20200921120000 20200921120000
upgradeFirmware 013 013
sdupdate - auto upgrade file from mmc to flash

Usage:
sdupdate LOAD_ID ADDR_START ADDR_END
LOAD_ID: 0-->u-boot
         1-->kernel
         2-->rootfs
         3-->demo.bin
ex:
        sdupdate   (update all)
or
        sdupdate 0 0x0 0x40000
Enter key to stop autoboot in 3 seconds
the manufacturer 1c
SF: Detected EN25QH128A

--->probe spend 4 ms
SF: 2621440 bytes @ 0x50000 Read: OK
--->read spend 842 ms
## Booting kernel from Legacy Image at 80600000 ...
   Image Name:   Linux-3.10.14__isvp_swan_1.0__
   Image Type:   MIPS Linux Kernel Image (lzma compressed)
   Data Size:    1727656 Bytes = 1.6 MiB
   Load Address: 80010000
   Entry Point:  803c7810
   Verifying Checksum ... OK
   Uncompressing Kernel Image ... OK

Starting kernel ...

现在的问题是，根据提示“Enter key to stop autoboot in 3 seconds”中断启动不成功，不管按什么键都会照常启动内核。ttl 连接确认没问题，是可以正常输入的。在内核启动开始跑 log 后按键会有一个登陆提示 Ingenic-uc1_1 login: 然后继续跑码。

我的疑惑是：

看类似的教程，即使有 u-boot 密码，也是在按任意键停止启动后不跑码了才出登陆提示，那我这边出现的登陆提示到底是进入 u-boot 的登陆，还是其他的？
为什么无法中断启动，是设置了特殊的按键吗？
根据日志内容提示可以用 sdupdate 命令更新 u-boot ，假如我无法找到正确的密码，我可以直接用该命令覆盖一个新的 u-boot 上去吗？

希望各位大佬解惑。