cirrusdrmfb broken with simplefb

Commit Message

Takashi Iwai Dec. 19, 2013, 11:06 a.m. UTC

At Thu, 19 Dec 2013 11:46:51 +0100,
David Herrmann wrote:
> 
> Hi
> 
> On Thu, Dec 19, 2013 at 1:03 AM, One Thousand Gnomes
> <[e-mail]> wrote:
> >> > That bug always existed, simplefb is just the first driver to hit it
> >> > (vesafb/efifb didn't use resources). I'm aware of the issue but as a
> >> > workaround you can simply disable CONFIG_X86_SYSFB. That restores
> >> > the old behavior.
> >>
> >> This looks like a regression, so we'll either need a fix or we'll have
> >> to mark CONFIG_X86_SYSFB as CONFIG_BROKEN.
> >
> > Kernel bugzilla has entries for simplefb breaking both vesafb and matrox
> > mga.
> 
> Thanks for the hints. I've read through all I could find and tried to
> provide some help.
> 
> I'm kind of confused, most of them enable CONFIG_X86_SYSFB (which is
> 'n' by default) but don't read the help text. I did my best to tell
> people that this option requires CONFIG_FB_SIMPLE, but if you don't
> read the help-text you won't notice that. Don't know what to do about
> that..

You can set FB_SIMPLE default value depending on X86_SYSFB, something
like:



Takashi
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Comments

David Herrmann Dec. 19, 2013, 12:36 p.m. UTC | #1

Hi

On Thu, Dec 19, 2013 at 12:06 PM, Takashi Iwai <[e-mail]> wrote:
> At Thu, 19 Dec 2013 11:46:51 +0100,
> David Herrmann wrote:
>>
>> Hi
>>
>> On Thu, Dec 19, 2013 at 1:03 AM, One Thousand Gnomes
>> <[e-mail]> wrote:
>> >> > That bug always existed, simplefb is just the first driver to hit it
>> >> > (vesafb/efifb didn't use resources). I'm aware of the issue but as a
>> >> > workaround you can simply disable CONFIG_X86_SYSFB. That restores
>> >> > the old behavior.
>> >>
>> >> This looks like a regression, so we'll either need a fix or we'll have
>> >> to mark CONFIG_X86_SYSFB as CONFIG_BROKEN.
>> >
>> > Kernel bugzilla has entries for simplefb breaking both vesafb and matrox
>> > mga.
>>
>> Thanks for the hints. I've read through all I could find and tried to
>> provide some help.
>>
>> I'm kind of confused, most of them enable CONFIG_X86_SYSFB (which is
>> 'n' by default) but don't read the help text. I did my best to tell
>> people that this option requires CONFIG_FB_SIMPLE, but if you don't
>> read the help-text you won't notice that. Don't know what to do about
>> that..
>
> You can set FB_SIMPLE default value depending on X86_SYSFB, something
> like:
>
> --- a/drivers/video/Kconfig
> +++ b/drivers/video/Kconfig
> @@ -2455,6 +2455,7 @@ config FB_HYPERV
>  config FB_SIMPLE
>         bool "Simple framebuffer support"
>         depends on (FB = y)
> +       default y if X86_SYSFB
>         select FB_CFB_FILLRECT
>         select FB_CFB_COPYAREA
>         select FB_CFB_IMAGEBLIT

The "default <wx> if <yz>" only works if the config hasn't been set at
all, yet. Even a "# CONFIG_* is unset" causes the "default" value to
be ignored.

How about adding "depends on (FB_SIMPLE = y)" for X86_SYSFB? I guess I
will try that and send a patch.

Thanks
David
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Patch

--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -2455,6 +2455,7 @@  config FB_HYPERV
 config FB_SIMPLE
 	bool "Simple framebuffer support"
 	depends on (FB = y)
+	default y if X86_SYSFB
 	select FB_CFB_FILLRECT
 	select FB_CFB_COPYAREA
 	select FB_CFB_IMAGEBLIT