public inbox for u-boot@lists.denx.de
 help / color / mirror / Atom feed
From: Siarhei Siamashka <siarhei.siamashka@gmail.com>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH] Revert "sunxi: dram: Use divisor P=1 for PLL5"
Date: Wed, 15 Oct 2014 13:34:20 +0300	[thread overview]
Message-ID: <20141015133420.75921bd7@i7> (raw)
In-Reply-To: <1413367931-4224-1-git-send-email-hdegoede@redhat.com>

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

  reply	other threads:[~2014-10-15 10:34 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-10-15 10:12 [U-Boot] [PATCH] Revert "sunxi: dram: Use divisor P=1 for PLL5" Hans de Goede
2014-10-15 10:34 ` Siarhei Siamashka [this message]
2014-10-16  8:48   ` Hans de Goede
2014-10-16  9:49     ` Ian Campbell
2014-10-16  9:59     ` Siarhei Siamashka
2014-10-16 20:10     ` Jeroen Hofstee
2014-10-21 20:58     ` Tom Rini
2014-10-22  8:14       ` Ian Campbell
2014-10-22  8:35         ` Hans de Goede
2014-10-22  9:19           ` Ian Campbell
2014-10-22  9:26             ` Hans de Goede
2014-10-22  9:42               ` Ian Campbell

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20141015133420.75921bd7@i7 \
    --to=siarhei.siamashka@gmail.com \
    --cc=u-boot@lists.denx.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox