How to convert my existing eMMC Driver to make eMMC as bootable device

NTDEV
1

Hello All,

Currently i have a hardware which has SATA interface to which a SATA device is connected an the board also has a soldered eMMC[64GB]. We have a eMMC driver which already exisits. Now i want to make this driver support boot option as well.

Only infor which i got from Net was as specified in the link below.
https://msdn.microsoft.com/en-us/windows/hardware/drivers/storage/restrictions-on-miniport-drivers-that-manage-the-boot-drive

But when i want to install the OS, during the installation process when the system asks for which drive you want to install OS, my eMMC drive is not seen ?
I Installed the driver for my eMMC controller also using load driver option during installation…but no luck.

Can any one help me in this ? What changes i need to do the driver to support boot from eMMC ?

regards,
jaggi

2

The amount of details you have given makes it quite open ended as to what could be the issue. I will put my thoughts related to this

W.R.T. your storage device not showing up :

  • After loading the driver, did you check that the driver was really loaded ?
  • Did you check the setup* logs to check for any driver installation issues ?
  • After trying to load the driver, did it show any error on the UI ?
  • Tip : You can open command prompt by pressing Shift + F10 during Windows installation. From there, can you run Diskpart and check if your device is listed and not offline ? IIRC, for offline case, it would still show in the UI but don’t remember exactly
  • Which version of Windows are you trying to install ?
  • Are you meeting the driver signing requirements for the OS you are trying to install ? During installation, and for boot load drivers, IIRC, there are some cross signing requirements that are not there for run time ? I think the setup logs should point out of signing is an issue.

W.R.T.your intention to boot from the device :

  • Does your device allow at least read capability to BIOS / UEFI ? If not, then even if you manage to install Windows by providing drivers at the time of installation, you will not be able to reboot the machine to use the installed Windows
  • Have you modified the inf for marking it boot load ? Again needed for post-reboot.
3

Thanks a lot Anand for that early reply…

I understand what all info i need to provide you so that you help me with your expertise. Tomorrow I will do the experiments which you have specified and provide the details.

regards,
Jagadish Hadimani