Hi Bin, On 7 October 2015 at 09:24, Bin Meng <bmeng...@gmail.com> wrote: > Hi Simon, > > On Sat, Oct 3, 2015 at 10:29 PM, Simon Glass <s...@chromium.org> wrote: >> Hi Bin, >> >> On 1 October 2015 at 08:36, Bin Meng <bmeng...@gmail.com> wrote: >>> Add a Kconfig option to disable the Integrated Graphics Device (IGD) >>> so that it does not show in the PCI configuration space as a VGA >>> disaplay controller. This gives a chance for U-Boot to run PCI/PCIe >>> based graphics card's VGA BIOS and use that for the graphics console. >>> >>> Signed-off-by: Bin Meng <bmeng...@gmail.com> >>> >>> --- >>> >>> arch/x86/cpu/queensbay/Kconfig | 8 ++++++++ >>> arch/x86/cpu/queensbay/tnc.c | 19 +++++++++++++++++++ >>> arch/x86/include/asm/arch-queensbay/tnc.h | 5 +++++ >>> include/configs/crownbay.h | 1 + >>> 4 files changed, 33 insertions(+) >> >> Acked-by: Simon Glass <s...@chromium.org> >> >> But do we really want configs for such device-specific things? I >> wonder if device tree would be better. E.g. add 'status = "disabled"' >> in the PCI node. >> > > I am not sure if I understand you correctly. To me 'status = > "disabled"' is a generic device binding, and when it comes to PCI > device, how do we define a device is in a 'disabled' state? Is it we > program the COMMAND register to disable bus master, mem and I/O > access? Or we program a chipset-specific register (Intel chipset > normally has such) to make it invisible from PCI configuration space > completely? And as you said, this is really chipset-specific thing, so > I chose to do via a platform-specific configuration macro, instead of > doing such work under a generic bindings ..
Yes we don't have a good way to notice that a driver is disabled - it will never be bound in that case. If there were a driver for the SoC, then perhaps we could add config options to that node. Then the chipset-specific SoC driver could do the required init. Regards, Simon _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot