The four x16 DDR3 are wired in T-topology. From NXP AN4467:
'Although not required, T-Topologies may also benefit from performing
Write Leveling as there are package delays on both the processor and DDR
devices that can be de-skewed by performing Write Leveling. Therefore,
Freescale recommends determining Write Leveling calibration parameters
for all boards, regardless of topology used.'
That is why write level calibration is also done.
Signed-off-by: Ludwig Zenz <lzenz@dh-electronics.com>
The existing calibration values were found to be incorrect
in comparison to newly determined values.
The new values were generated with the help of 5 boards. They have
been determined with the NXP Utility 'DDR Stress Test (2.9.0)'.
Signed-off-by: Ludwig Zenz <lzenz@dh-electronics.com>
This reverts commit a637fe6f27.
The DDR DRAM calibration was enhanced by write leveling correction code.
It can be used with T-topology now.
Signed-off-by: Ludwig Zenz <lzenz@dh-electronics.de>
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from. So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry. Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.
In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.
This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents. There's also a few places where I found we did not have a tag
and have introduced one.
Signed-off-by: Tom Rini <trini@konsulko.com>
We have a large number of places where while we historically referenced
gd in the code we no longer do, as well as cases where the code added
that line "just in case" during development and never dropped it.
Signed-off-by: Tom Rini <trini@konsulko.com>
The DDR DRAM calibration doesn't work on T-topology sometimes, so disable it.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Stefano Babic <sbabic@denx.de>
The board uses T-topology for the four x16 DRAM chips, so remove
the write-leveling from the SPL as that is only usefly on fly-by
topology and can be harmful on T-topology. Also update the DRAM
timing with values from calibration on multiple boards.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Stefano Babic <sbabic@denx.de>
Add support for the DHCOM i.MX6 PDK board. This board has:
- FEC ethernet
- EHCI USB host
- 3x SDMMC
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Stefano Babic <sbabic@denx.de>
