[U-Boot] [PATCH] Revert "sunxi: dram: Use divisor P=1 for PLL5"

Siarhei Siamashka
2014-10-15T10:34:20Z

On Wed, 15 Oct 2014 12:12:11 +0200
Hans de Goede <hdegoede@redhat.com> wrote:

> This change breaks various hardcoded assumptions in the linux-sunxi-3.4
> kernels, causing a divide by 0 error in the linux-sunxi-3.4 nand driver,
> rendering 3.4 kernels unbootable. Besides this problem, it also breaks LCD
> output (on devices without nand).
>
> Fixes for these issues are being added to the linux-sunxi-3.4 kernel, but for
> now it seems better to revert this.
>
> This reverts commit 013f2d746955147439215a4939655c9ed6bdd866.

As mentioned in the commit message
https://www.mail-archive.com/linux-sunxi at googlegroups.com/msg07884.html
the hardcoded assumptions in the sunxi-3.4 kernel are still bad
with or without this revert if somebody tries to use higher DRAM
clock speeds.

The patch in question just smokes out bugs, which are otherwise still
there.

Going forward, the mainline kernel needs the G2D driver and it needs
to run at a decent clock speed to be provide reasonable performance.
Low PLL5P clock speed is limiting our options.

This revert does not do anyone any favour and only postpones the
resolution of the problem.

--
Best regards,
Siarhei Siamashka