[U-Boot] [PATCH] [v2] powerpc: 'monitor' environment variable contains full video configuration

Timur Tabi
2011-03-15T22:32:23Z

Wolfgang Denk wrote:
> Please re-read the conversation then. Mind the context (U-Boot versus
> Linux). Mind what I wrote about defaults and users being able to
> chose the behaviour they want. And keep in mind what I wrote about
> enforcing desicions "in the best interest" of your users (who may
> happen to disagree).

After re-reading it, I've come to the conclusion is that as far as my patch is
concerned, I just need to make the following changes:

1) Modify video_get_params() (in videomodes.c) to parse the "video-mode
"environment variable, using the same format that Linux uses. Right now, it
parses the variable "video", so that variable is now deprecated.

2) Update the DIU driver to use this feature of videomodes.c. This means taking
the functionality of my function diu_get_video_params() and putting it into
video_get_params().

3) Remove the code that sets diubootargs. If the user wants to pass parameters
to Linux, he has to add "video=$video-mode console=tty0" to his command-line.
If "video-mode" is not set, then he must *not* add "video=$video-mode
console=tty0" to his command-line, otherwise the kernel will get confused.
There is no way to automate this for the user.

And that's it. If this is wrong, please be detailed in what I have wrong,
because I can't guess any more what you want.

So I have one concern:

My patch has a function called diu_get_video_params() which is like
video_get_params(), but it returns a lot more information. video_get_params()
is currently used by several other drivers, none of which I can test. I'm very
hesitant to rewrite video_get_params() so that it returns the same data that
diu_get_video_params() returns, because I can't test these other boards.

--
Timur Tabi
Linux kernel developer at Freescale