On Saturday, November 09, 2013 06:36:11 PM al.stone@linaro.org wrote:
> From: Al Stone <ahs3@redhat.com>
>
> To enable the hardware reduced mode of ACPI on some platforms (such as
> ARM), we need to modify the kernel code and set ACPI_REDUCED_HARDWARE
> to TRUE in the ACPICA source.
>
> This can be done more resonably by introducing a kernel config item
> to enable/disable ACPI_REDUCED_HARDWARE.  We can then change the kernel
> config instead of having to modify the kernel source directly to enable
> the reduced hardware mode of ACPI.
>
> Lv Zheng suggested that this configuration item does not belong in ACPICA,
> the upstream source for much of the ACPI internals, but rather to the
> Linux kernel itself.  Hence, we introduce this flag so that we can make
> ACPI_REDUCED_HARDWARE configurable.  For the details of the discussion,
> please refer to: http://www.spinics.net/lists/linux-acpi/msg46369.html
>
> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
> Signed-off-by: Al Stone <al.stone@linaro.org>
> ---
>  drivers/acpi/Kconfig            | 8 ++++++++
>  include/acpi/platform/aclinux.h | 4 ++++
>  2 files changed, 12 insertions(+)
>
> diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
> index 589da05..7bbd3b0 100644
> --- a/drivers/acpi/Kconfig
> +++ b/drivers/acpi/Kconfig
> @@ -354,6 +354,14 @@ config ACPI_BGRT
>         data from the firmware boot splash. It will appear under
>         /sys/firmware/acpi/bgrt/ .
>
> +config ACPI_REDUCED_HARDWARE
> +     bool "Hardware-reduced ACPI support"
> +     depends on !(IA64 || X86)

Why don't you use

        depends on (ARM || ARM64)

here instead?

hardware-reduced is not restricted to ARM platforms, that's why

I used depends on !(IA64 || X86) here.

Thanks

Hanjun