Re: Improvements for the PS3

Hi Geoff, Frederik,

On Thu, Jul 19, 2018 at 12:40 AM Geoff Levand [off-list ref] wrote:

On 07/14/2018 09:49 AM, Fredrik Noring wrote:

quoted

so I added a sleep with

+     msleep(10000);

I can't see where you added the sleep, but 10s seems excessive.
If the real reason is the need to wait for an interrupt for ps3fb_sync_imag=
e(),
then waiting for 40 ms should be sufficient? Or am I missing something?

quoted

+
      return 0;

et voil=C3=A0, the screen came alive and the kernel panic was revealed!=

 It seems

quoted

the kernel panics so fast that the PS3 frame buffer is unprepared. This=

 is,

quoted

of course, very unfortunate because trying to debug the boot process wi=

thout

quoted

a screen or any other means of obtaining console text is quite difficul=

t.

We could add a fixed delay there, but I'd like to avoid waiting that
long on every boot.  Why don't you add a kernel module_param named
something like ps3fb_delay that takes a value in milliseconds and a
default of zero.  See:

  https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree=

/drivers/video/fbdev/ps3fb.c?h=3Dv4.17#n260

quoted

I suppose the problem is that it relies on interrupts for ps3fb_sync_im=

age

quoted

to regularly copy the image, hence without them the screen isn't update=

d to

quoted

show kernel panics, etc. Perhaps one way to fix that is to implement th=

e

quoted

struct fb_tile_ops API, so that the console is synchronously updated? W=

ould

quoted

that be acceptable?

I'm not sure if that would work or not.   Maybe Geert is more familiar wi=

th it.

That sounds like a complex solution, slowing down the console a lot.

What about letting ps3fb register a panic notifier to sync the screen, like
hyperv_fb does?

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. Bu=
t
when I'm talking to journalists I just say "programmer" or something like t=
hat.
                                -- Linus Torvalds