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The title pretty much sums it all up, I was just curious as I don't understand the MTK preloader that much and considering if a wrong one is flashed then you are left with unrecoverable brick (correct me if i'm be wrong) so it seemed odd to me that it would be kept in the same flash as other partitions like system, data, cache etc.

I have tried checking checking some partitions directly from the phone which seem to indicate that it might be sharing the same flash memory as other partitions but the scatter files that I have seem to indicate otherwise, I also did some xda-delopers searches but it left me even more confused.

Any help will be appreciated.

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It's present in the Boot ROM, not a directly visible partition in the eMMC.

Source: MediaTek details: SoC startup

The Boot ROM will be embedded inside the processor chip in generic chipsets. (read more) (no idea about MTK)

Further Technical details on working of Preloader: MediaTek details: Partitions and Preloader

  • The links have been helpful, but they all seem to point out that Boot ROM memory is read-only, if that's the case how comes it is possible to flash a preloader, am i missing something? – AguThadeus Oct 9 '16 at 16:32
  • Yes, it's confusing.. As far as I have understood, it's not listed as a partition in the partition table, But I nowhere see if it's present in the flash itself or a separate memory.. These things are propriety to MTK and they won't reveal it, unless someone reverse engineers and finds it out.. – Gokul NC Oct 10 '16 at 6:02
  • Thanks, let me check some chinese forums perhaps I might get something – AguThadeus Oct 10 '16 at 6:59
  • @GokulNC OR rips an MTK phone apart. – Dan Brown Oct 10 '16 at 14:52
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Preloader is most certainly a partition visible in a smart device's partition index/filesystem. This partition is present on virtually every Lenovo device manufactured today. It is not embedded in the processor chip, but rather is located within the eMMC SD internal storage. So to answer your original question, yes, the MTK preloader is in the same eMMC flashable storage card as /system, /boot, /data, etc.

  • I don't think that is the case because I tried dumping /dev/block/mmcblk0 (which is the device containing the various partitions in my device) starting from the first memory block using dd, I then examined it using a hexeditor searching for any presence of preloader signature but there wasn't any, I have an untested hypothesis that perhaps the emmc is abstracted into memory regions and only certain regions are visible in normal mode but I am still not sure 100% – AguThadeus Nov 4 '17 at 12:31
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Preloader is present in eMMC.

/dev/block/mmcblk0 is located in eMMC as linear address.mmcblk0 starts with mbr, not including preloader. You can easily check by putting this mmcblk0 in eMMC raw tool and by clicking Load partition structure button.

But preloader is located as logical address.

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Yes it is stored on the same storage as the rest of the partitions except in it's own partition, Think of it like Three Partitions or Regions
1, Boot0
2, Boot1,
3, EMMC

1 holds your preloader
2 usually holds nothing from my personal experience
3 is like an extended partition
( a partition that holds more partitions ) and holds your system, data, cache etc...


You can use SP Flash Tool to check this yourself by making a readback of the different regions and inspecting them with a hex editor

  • I think this confirms my assumptions, I found about this a while ago but was reluctant to post it as an answer because I wasn't completely sure. I don't know about the naming used in your phone but all phones I have examined have three regions EMMC_BOOT_1 for preloader, EMMC_BOOT_2 (contains null bytes) and EMMC_USER which is used as mmcblk0 holding other phone partitions – AguThadeus Mar 26 '18 at 10:14
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Hello im little late to this post

You can buy special dongles or flash box such as Infinity Cm2 and do read firmware, this way you will be able to dump firmware in Factory format and do some debugging Usually the preloader file located in boot0 or recent in Boot1

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