7670-7400v2-PCN

New eMMC Revisions

Synopsis	Due to reasons beyond our control, the eMMC devices used on this product are no longer available. This new parts include an updated revision marker in a register read by the kernel. A kernel modification is required for it to properly use the new parts.
Severity	Moderate
Class	Necessary kernel change
Affected	TS-7670, TS-7400-V2
Status	Kernel updates complete

Description:

With the changed eMMC device, a static version indication register was changed as well. The existing kernel software checks for specific revisions. Because of this, existing images and kernel builds before the patch was applied will refuse to finish setting up the eMMC device, making it appear absent from the system

Identification:

Any kernel builds of commit 74c87c2a1d83893cccb23ad1d1c406ec6cafb2d3 or newer will resolve any issues. An older kernel with the newer eMMC chip will have output in the kernel logs similar to: "mmc: unrecognised EXT_CSD structure version XXX"

Necessary Action:

All new shipping units will have the proper kernel installed on both eMMC and any microSD cards ordered with the unit as well. Any custom software or production modifications that leave the existing kernel intact will not require any further changes.

If the end production process or software modifies the kernel binary, then the kernel binary and modules that are written to the boot media must be of kernel commit 74c87c2a1d83893cccb23ad1d1c406ec6cafb2d3 or newer. This will require a kernel rebuild and reinstall on the master image used. Information on compiling the kernel can be found here.