* Re: [PATCH] gma500: gtt based hardware scrolling console
[not found] <20110922184316.25068.54702.stgit@localhost.localdomain>
@ 2011-09-22 19:40 ` Geert Uytterhoeven
2011-09-22 20:21 ` Alan Cox
0 siblings, 1 reply; 3+ messages in thread
From: Geert Uytterhoeven @ 2011-09-22 19:40 UTC (permalink / raw)
To: Alan Cox; +Cc: greg, linux-kernel, Linux Fbdev development list
Hi Alan,
On Thu, Sep 22, 2011 at 20:43, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
diff --git a/drivers/staging/gma500/framebuffer.c
b/drivers/staging/gma500/framebuffer.c
index 7748331..3f39a37 100644
--- a/drivers/staging/gma500/framebuffer.c
+++ b/drivers/staging/gma500/framebuffer.c
> @@ -416,6 +473,8 @@ static int psbfb_create(struct psb_fbdev *fbdev,
>
> info->fix.smem_start = dev->mode_config.fb_base;
> info->fix.smem_len = size;
> + info->fix.ywrapstep = gtt_roll;
Do you really want to set this? I didn't see any other wrapping
support in your patch.
However, I guess you can implement wrapping support using the same
mapping trick?
> + info->fix.ypanstep = gtt_roll;
>
> if (backing->stolen) {
> /* Accessed stolen memory directly */
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] gma500: gtt based hardware scrolling console
2011-09-22 19:40 ` [PATCH] gma500: gtt based hardware scrolling console Geert Uytterhoeven
@ 2011-09-22 20:21 ` Alan Cox
2011-09-23 5:17 ` Geert Uytterhoeven
0 siblings, 1 reply; 3+ messages in thread
From: Alan Cox @ 2011-09-22 20:21 UTC (permalink / raw)
To: Geert Uytterhoeven; +Cc: greg, linux-kernel, Linux Fbdev development list
> > + info->fix.ywrapstep = gtt_roll;
>
> Do you really want to set this? I didn't see any other wrapping
> support in your patch.
> However, I guess you can implement wrapping support using the same
> mapping trick?
It is actually wrapping - it writes the low pages back below the high
ones so it works the GTT as a circular buffer - or am I misunderstanding
this.
One thing I wasn't sure of on the fb side. If I've got a display width
that is annoying and can't fit on a 4Kbyte stride am I right in thinking
I can set this to say 8 and use a 512 byte stride and still get
acceleration for the usual font choice ?
Alan
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] gma500: gtt based hardware scrolling console
2011-09-22 20:21 ` Alan Cox
@ 2011-09-23 5:17 ` Geert Uytterhoeven
0 siblings, 0 replies; 3+ messages in thread
From: Geert Uytterhoeven @ 2011-09-23 5:17 UTC (permalink / raw)
To: Alan Cox; +Cc: greg, linux-kernel, Linux Fbdev development list
On Thu, Sep 22, 2011 at 22:21, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
>> > + info->fix.ywrapstep = gtt_roll;
>>
>> Do you really want to set this? I didn't see any other wrapping
>> support in your patch.
>> However, I guess you can implement wrapping support using the same
>> mapping trick?
>
> It is actually wrapping - it writes the low pages back below the high
> ones so it works the GTT as a circular buffer - or am I misunderstanding
> this.
Then it should not set ypanstep to a non-zero value, and set/handle the other
various *YWRAP flags, to communicate with the frame buffer console driver.
Panning is moving inside a virtual screen bigger than the visible screen size.
> One thing I wasn't sure of on the fb side. If I've got a display width
> that is annoying and can't fit on a 4Kbyte stride am I right in thinking
> I can set this to say 8 and use a 512 byte stride and still get
> acceleration for the usual font choice ?
Yep, that should work. The console code can use ywrap resp. ypan if the
font height is a multiple of ywrapstep resp. ypanstep.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2011-09-23 5:17 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
[not found] <20110922184316.25068.54702.stgit@localhost.localdomain>
2011-09-22 19:40 ` [PATCH] gma500: gtt based hardware scrolling console Geert Uytterhoeven
2011-09-22 20:21 ` Alan Cox
2011-09-23 5:17 ` Geert Uytterhoeven
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).