[U-Boot] [PATCH v2] x86: make the LAPIC / IOAPIC construct switchable with Kconfig

[Bin Meng]

On Mon, Nov 19, 2018 at 6:19 AM Hannes Schmelzer <oe5hpm at oevsv.at> wrote:
>
> There are still systems running which do not have any LAPIC or even
> IOAPIC. Responsible MSRs for those do not exist and the systems are
> crashing on trying setup LAPIC.
>
> So this commit makes the APIC stuff able to switch off for those boards
> which dont' have a LAPIC / IOAPIC.
>
> Signed-off-by: Hannes Schmelzer <oe5hpm at oevsv.at>
> ---
>
> Changes in v2:
> - rebase to curent master
> - reword commit message to be more clear
> - fix typo in Kconfig
> - re-add blank line in interrupt.c
>
>  arch/x86/Kconfig              | 9 +++++++++
>  arch/x86/cpu/Makefile         | 2 +-
>  arch/x86/cpu/i386/interrupt.c | 2 ++
>  3 files changed, 12 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index a1c18d2..8d839e4 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -736,6 +736,15 @@ config I8259_PIC
>           slave) interrupt controllers. Include this to have U-Boot set up
>           the interrupt correctly.
>
> +config APIC
> +       bool
> +       default y
> +       help
> +         The (A)dvanced (P)rogrammable (I)nterrupt (C)ontroller is responsible
> +         for catching interrupts and distributing them to one more CPU cores.

one "or" more

> +         In most cases there is some LAPIC (local) for each core and one

There are some LAPICs

> +         I/O APIC. This conjunction is found on most modern x86 systems.
> +
>  config PINCTRL_ICH6
>         bool
>         help
> diff --git a/arch/x86/cpu/Makefile b/arch/x86/cpu/Makefile
> index f862d8c..54668aa 100644
> --- a/arch/x86/cpu/Makefile
> +++ b/arch/x86/cpu/Makefile
> @@ -35,7 +35,7 @@ obj-$(CONFIG_NORTHBRIDGE_INTEL_IVYBRIDGE) += ivybridge/
>  obj-$(CONFIG_INTEL_QUARK) += quark/
>  obj-$(CONFIG_INTEL_QUEENSBAY) += queensbay/
>  obj-$(CONFIG_INTEL_TANGIER) += tangier/
> -obj-y += lapic.o ioapic.o
> +obj-$(CONFIG_APIC) += lapic.o ioapic.o
>  obj-y += irq.o
>  ifndef CONFIG_$(SPL_)X86_64
>  obj-$(CONFIG_SMP) += mp_init.o
> diff --git a/arch/x86/cpu/i386/interrupt.c b/arch/x86/cpu/i386/interrupt.c
> index ed8423e..bf9526b 100644
> --- a/arch/x86/cpu/i386/interrupt.c
> +++ b/arch/x86/cpu/i386/interrupt.c
> @@ -264,8 +264,10 @@ int interrupt_init(void)
>         i8259_init();
>  #endif
>
> +#ifdef CONFIG_APIC
>         lapic_setup();
>
> +#endif

oops, I meant to say the #endif should be followed immediately and
leave the blank line between the #endif and the next line.

>         /* Initialize core interrupt and exception functionality of CPU */
>         cpu_init_interrupts();
>
> --

Reviewed-by: Bin Meng <bmeng.cn at gmail.com>

I can fix all above nits when applying.

Regards,
Bin