| Message ID | f6db4d0a-3578-4162-5de7-6e699f7a02c2@de.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, 21 Feb 2018 12:49:35 +0100 Christian Borntraeger <borntraeger@de.ibm.com> wrote: > On 02/21/2018 12:29 PM, Thomas Huth wrote: > > On 21.02.2018 12:22, Christian Borntraeger wrote: > >> > >> > >> On 02/21/2018 12:14 PM, Thomas Huth wrote: > >>> On 21.02.2018 12:09, Christian Borntraeger wrote: > >>>> > >>>> > >>>> On 02/21/2018 11:32 AM, Cornelia Huck wrote: > >>>>> On Wed, 21 Feb 2018 11:22:38 +0100 > >>>>> Christian Borntraeger <borntraeger@de.ibm.com> wrote: > >>>>> > >>>>>> On 02/21/2018 11:05 AM, Christian Borntraeger wrote: > >>>>>>> > >>>>>>> > >>>>>>> On 02/19/2018 05:38 PM, Farhan Ali wrote: > >>>>>>>> > >>>>>>>> > >>>>>>>> On 02/19/2018 11:25 AM, Thomas Huth wrote: > >>>>>>>>> On 19.02.2018 16:47, Farhan Ali wrote: > >>>>>>>>>> The 'commit e25df1205f37 ("[S390] Kconfig: menus with depends on HAS_IOMEM.")' > >>>>>>>>>> added the HAS_IOMEM dependecy for "Graphics support". This disabled the > >>>>>>>>>> "Graphics support" menu for S390. But if we enable VT layer for S390, > >>>>>>>>>> we would also need to enable the dummy console. So let's remove the > >>>>>>>>>> HAS_IOMEM dependency. > >>>>>>>>>> > >>>>>>>>>> Move this dependency to sub menu items and console drivers that use > >>>>>>>>>> io memory. > >>>>>>>>>> > >>>>>>>>>> Signed-off-by: Farhan Ali <alifm@linux.vnet.ibm.com> > >>>>>>>>>> --- > >>>>>>>>>> drivers/video/Kconfig | 21 +++++++++++---------- > >>>>>>>>>> drivers/video/console/Kconfig | 4 ++-- > >>>>>>>>>> 2 files changed, 13 insertions(+), 12 deletions(-) > >>>>>>>>>> > >>>>>>>>>> diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig > >>>>>>>>>> index 3c20af9..8f10915 100644 > >>>>>>>>>> --- a/drivers/video/Kconfig > >>>>>>>>>> +++ b/drivers/video/Kconfig > >>>>>>>>>> @@ -3,7 +3,6 @@ > >>>>>>>>>> # > >>>>>>>>>> menu "Graphics support" > >>>>>>>>>> - depends on HAS_IOMEM > >>>>>>>>>> config HAVE_FB_ATMEL > >>>>>>>>>> bool > >>>>>>>>>> @@ -11,20 +10,22 @@ config HAVE_FB_ATMEL > >>>>>>>>>> config SH_LCD_MIPI_DSI > >>>>>>>>>> bool > >>>>>>>>>> -source "drivers/char/agp/Kconfig" > >>>>>>>>>> +if HAS_IOMEM > >>>>>>>>>> + source "drivers/char/agp/Kconfig" > >>>>>>>>>> -source "drivers/gpu/vga/Kconfig" > >>>>>>>>>> + source "drivers/gpu/vga/Kconfig" > >>>>>>>>>> -source "drivers/gpu/host1x/Kconfig" > >>>>>>>>>> -source "drivers/gpu/ipu-v3/Kconfig" > >>>>>>>>>> + source "drivers/gpu/host1x/Kconfig" > >>>>>>>>>> + source "drivers/gpu/ipu-v3/Kconfig" > >>>>>>>>>> -source "drivers/gpu/drm/Kconfig" > >>>>>>>>>> + source "drivers/gpu/drm/Kconfig" > >>>>>>> > >>>>>>> > >>>>>>> Hmmm, looks like that this makes it impossible to select VIRTIO_GPU - need still more > >>>>>>> work. > >>>>>>> > >>>>>> Sorry my fault. I had CONFIG_PCI disabled. > >>>>> > >>>>> That smells like the s390 HAS_IOMEM stuff needs more work -- I guess > >>>>> that you want to enable a ccw virtio-gpu device, not a pci one, right? > >>>> > >>>> It is a ccw virtio-gpu. But s390 has no IOMEM without CONFIG_PCI, so you cannot > >>>> select VIRTIO_GPU, which needs DRM, which need IOMEM. > >>> > >>> So the 'source "drivers/gpu/drm/Kconfig"' should maybe rather reside > >>> outside of the "if HAS_IOMEM" path? Or does it not compile anymore that way? > >> > >> virtio-gpu depends on drm. So in essence it boils down to if you want virtio-gpu > >> you also need to enable PCI, even if the actual channel is ccw. > > > > But if you need to enable PCI to get IOMEM, I wonder why this patch here > > is needed at all? The Graphics menu / VT dummy console should be > > available in the config if IOMEM is enabled anyway? > > That is a good question. With CONFIG_PCI=y I can select virtio-gpu and dummy-console. > IIRC the issue was that with patch 3 we can have the situation where we have > CONFIG_VT = y and CONFIG_DUMMY_CONSOLE=n and this will crash early during boot as > conswitchp is NULL. So in practice, CONFIG_VT depends on "there's a console available, even if it's only the dummy one"? > This patches goal was to always enable dummy console even without > PCI, but it obviously fails to do so. OTOH, the dummy console really should not depend on anything, as it is only doing dummy things. > > So what about allowing CONFIG_VT on s390 only if we have PCI? > > > diff --git a/drivers/tty/Kconfig b/drivers/tty/Kconfig > index 84810075a6a0..1c7fe09d6f90 100644 > --- a/drivers/tty/Kconfig > +++ b/drivers/tty/Kconfig > @@ -11,7 +11,7 @@ if TTY > > config VT > bool "Virtual terminal" if EXPERT > - depends on !UML > + depends on !UML && (!S390 || PCI) > select INPUT > default y > ---help--- > Would cover your use case, but feels wrong to me... config dependencies aren't fun :/ -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 02/21/2018 01:07 PM, Cornelia Huck wrote: [...] >>> But if you need to enable PCI to get IOMEM, I wonder why this patch here >>> is needed at all? The Graphics menu / VT dummy console should be >>> available in the config if IOMEM is enabled anyway? >> >> That is a good question. With CONFIG_PCI=y I can select virtio-gpu and dummy-console. >> IIRC the issue was that with patch 3 we can have the situation where we have >> CONFIG_VT = y and CONFIG_DUMMY_CONSOLE=n and this will crash early during boot as >> conswitchp is NULL. > > So in practice, CONFIG_VT depends on "there's a console available, even > if it's only the dummy one"? Yes. Maybe we should simple move dummy_console outside of drivers/video/console/Kconfig into something that is always available. > >> This patches goal was to always enable dummy console even without >> PCI, but it obviously fails to do so. > > OTOH, the dummy console really should not depend on anything, as it is > only doing dummy things. > >> >> So what about allowing CONFIG_VT on s390 only if we have PCI? >> >> >> diff --git a/drivers/tty/Kconfig b/drivers/tty/Kconfig >> index 84810075a6a0..1c7fe09d6f90 100644 >> --- a/drivers/tty/Kconfig >> +++ b/drivers/tty/Kconfig >> @@ -11,7 +11,7 @@ if TTY >> >> config VT >> bool "Virtual terminal" if EXPERT >> - depends on !UML >> + depends on !UML && (!S390 || PCI) >> select INPUT >> default y >> ---help--- >> > > Would cover your use case, but feels wrong to me... config dependencies > aren't fun :/ > -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 02/21/2018 07:11 AM, Christian Borntraeger wrote: > > > On 02/21/2018 01:07 PM, Cornelia Huck wrote: > [...] >>>> But if you need to enable PCI to get IOMEM, I wonder why this patch here >>>> is needed at all? The Graphics menu / VT dummy console should be >>>> available in the config if IOMEM is enabled anyway? >>> >>> That is a good question. With CONFIG_PCI=y I can select virtio-gpu and dummy-console. >>> IIRC the issue was that with patch 3 we can have the situation where we have >>> CONFIG_VT = y and CONFIG_DUMMY_CONSOLE=n and this will crash early during boot as >>> conswitchp is NULL. Yes, VT layer initializes very early in the boot process and looks for a console. If it can't find any it will crash. I believe that was the whole point of having the dummy console. >> >> So in practice, CONFIG_VT depends on "there's a console available, even >> if it's only the dummy one"? > > Yes. Maybe we should simple move dummy_console outside of drivers/video/console/Kconfig > into something that is always available. > I agree, but where should it go? consoles are kinda tightly tied to video/Graphics Support. >> >>> This patches goal was to always enable dummy console even without >>> PCI, but it obviously fails to do so. >> This patch should enable the dummy console even without PCI but we won't have DRM/Virtio GPU. >> OTOH, the dummy console really should not depend on anything, as it is >> only doing dummy things. >> >>> >>> So what about allowing CONFIG_VT on s390 only if we have PCI? >>> >>> >>> diff --git a/drivers/tty/Kconfig b/drivers/tty/Kconfig >>> index 84810075a6a0..1c7fe09d6f90 100644 >>> --- a/drivers/tty/Kconfig >>> +++ b/drivers/tty/Kconfig >>> @@ -11,7 +11,7 @@ if TTY >>> >>> config VT >>> bool "Virtual terminal" if EXPERT >>> - depends on !UML >>> + depends on !UML && (!S390 || PCI) >>> select INPUT >>> default y >>> ---help--- >>> >> >> Would cover your use case, but feels wrong to me... config dependencies >> aren't fun :/ >> -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 02/21/2018 05:39 PM, Farhan Ali wrote: > > > On 02/21/2018 07:11 AM, Christian Borntraeger wrote: >> >> >> On 02/21/2018 01:07 PM, Cornelia Huck wrote: >> [...] >>>>> But if you need to enable PCI to get IOMEM, I wonder why this patch here >>>>> is needed at all? The Graphics menu / VT dummy console should be >>>>> available in the config if IOMEM is enabled anyway? >>>> >>>> That is a good question. With CONFIG_PCI=y I can select virtio-gpu and dummy-console. >>>> IIRC the issue was that with patch 3 we can have the situation where we have >>>> CONFIG_VT = y and CONFIG_DUMMY_CONSOLE=n and this will crash early during boot as >>>> conswitchp is NULL. > > Yes, VT layer initializes very early in the boot process and looks for a console. If it can't find any it will crash. I believe that was the whole point of having the dummy console. > >>> >>> So in practice, CONFIG_VT depends on "there's a console available, even >>> if it's only the dummy one"? >> >> Yes. Maybe we should simple move dummy_console outside of drivers/video/console/Kconfig >> into something that is always available. >> > > I agree, but where should it go? consoles are kinda tightly tied to video/Graphics Support. > >>> >>>> This patches goal was to always enable dummy console even without >>>> PCI, but it obviously fails to do so. >>> > This patch should enable the dummy console even without PCI but we won't have DRM/Virtio GPU. All right. This patch then makes sure that VT does not crash since it guarantees that DUMMY_CONSOLE is available. If the user want to have virtio-gpu it needs to enable PCI due to the dependencies, but this is a different issue that we can fix later. So the patch is fine as long as you take care of these things - add missing HAS_IOMEM dependency to VGA_CONSOLE - extend "if HAS_IOMEM" in drivers/video/Kconfig to cover config items previously covered by this dependency (it should start before config HAVE_FB_ATMEL and end after config HDMI) as requested by Bartlomiej -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/tty/Kconfig b/drivers/tty/Kconfig index 84810075a6a0..1c7fe09d6f90 100644 --- a/drivers/tty/Kconfig +++ b/drivers/tty/Kconfig @@ -11,7 +11,7 @@ if TTY config VT bool "Virtual terminal" if EXPERT - depends on !UML + depends on !UML && (!S390 || PCI) select INPUT default y ---help---