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Is UBoot able to boot via fatload/ext4load from an EMMC's General Purpose Partition or Boot Partition? I am able to show files from the User area, just not partitions created as hardware partitions. These partitions can be created by using UBoot's "mmc hwpartition" command. It seems odd UBoot can create these partitions, but doesn't seem to be able to use them. I am using the latest version (2016.4) of Xilinx's UBoot, which is based based on the UBoot

Using UBoot's "mmc info" command, UBoot can definitely see the Boot Partition and General Purpose Partitions (GP 1/2/3/4):

zynq-uboot> mmc info
Device: sdhci@e0100000
Manufacturer ID: fe
OEM: 14e
Name: MMC04
Tran Speed: 52000000
Rd Block Len: 512
MMC version 4.4.1
High Capacity: Yes
Capacity: 2.7 GiB
Bus Width: 4-bit
Erase Group Size: 4 MiB
HC WP Group Size: 4 MiB
User Capacity: 2.7 GiB
Boot Capacity: 16 MiB ENH
RPMB Capacity: 128 KiB ENH
GP1 Capacity: 128 MiB
GP2 Capacity: 64 MiB
GP3 Capacity: 128 MiB
GP4 Capacity: 512 MiB

Normally, I am able to use the UBoot commands: fatload/fatls or ext4load/ext4ls in order to show contents of a given partition based on its filesystem type.

Working example of fatls command - please note this is showing the contents of the User area (size 2.7GB from above).

zynq-uboot> fatls mmc 0:1
 17488 devicetree.dtb
 962589 fpga.bit
 54 uenv.txt
 6709360 uimage
 1555344 boot.bin
 33 image.chk
 83493724 image.tgz

7 file(s), 0 dir(s)

The GP partitions, when mounted in linux, contain my root filesystem, kernel image, etc. I would like to be able to boot from a GP partition via fatload/ext4load commands and use the User area for other purposes that storing my boot files.

I have found other posts about this topic, however, they don't seem to have been answered yet: https://lists.denx.de/pipermail/u-boot/2014-July/184731.html

Any help would be appreciated!

Yes, you can access the GP partitions from uboot.

As described here http://u-boot.10912.n7.nabble.com/How-to-access-GP-partitions-from-uboot-2015-04-td212394.html you can use the "mmc partconf" command's last argument to tell the eMMC to bring out different parts (e.g. the GP instead of the user area). After you run that command, and execute a "mmc read" command, you'll notice that you are reading from a different area.

Take care though. At least in my u-boot version (2017), u-boot does not know that is has to re-read the partition table, and for optimization purposes, it won't. I had to do a small patch in part.c in blk_get_device_by_str to force part_init to execute each time. Then, when you do a "mmc part", you should see the GP partition table as well, and can do any file operation as you would normally do. Don't foget that doing an "mmc rescan" or any reset of the eMMC will loose the GP state, and you'll have to switch back to the GP again to read it.