Re: [PATCH v10 00/21] Introduce ACPI for ARM64 based on ACPI 5.1

From: Julien Grall <julien.grall@linaro.org>
To: Naresh Bhat <naresh.bhat@linaro.org>, Hanjun Guo <guohanjun@huawei.com>
Cc: Hanjun Guo <hanjun.guo@linaro.org>,
	Jon Fraser <jfraser@broadcom.com>,
	Parth Dixit <parth.dixit@linaro.org>,
	Stefano Stabellini <stefano.stabellini@eu.citrix.com>,
	Catalin Marinas <Catalin.Marinas@arm.com>,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Olof Johansson <olof@lixom.net>,
	"grant.likely@linaro.org" <grant.likely@linaro.org>,
	Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>,
	Arnd Bergmann <arnd@arndb.de>,
	Mark Rutland <Mark.Rutland@arm.com>,
	"graeme.gregory@linaro.org" <graeme.gregory@linaro.org>,
	Sudeep Holla <Sudeep.Holla@arm.com>,
	"jcm@redhat.com" <jcm@redhat.com>,
	Marc Zyngier <Marc.Zyngier@arm.com>,
	Mark Brown <broonie@kernel.org>, Robert Richter <rric@kernel.org>,
	Timur Tabi <timur@codeaurora.org>,
	Ashwin Chaugule <ashwinc@codeaurora.org>,
	"suravee.suthikulpanit@amd.com" <suravee.suthikulpanit@amd.com>,
	"linux-acpi@vger.kernel.org" <linux-acpi@vger.kernel.org>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linaro-acpi@lists.linaro.org" <linaro-acpi@lists.linaro.org>,
	Ian Campbell <Ian.Campbell@citrix.com>
Subject: Re: [PATCH v10 00/21] Introduce ACPI for ARM64 based on ACPI 5.1
Date: Sun, 22 Mar 2015 21:05:21 +0000	[thread overview]
Message-ID: <550F2E91.7010109@linaro.org> (raw)
In-Reply-To: <CAFoFrHatzS3MwGVeOPPjY1R1sfBRYnJjgbQjvfzi6xS+XYD14g@mail.gmail.com>

Hello,

On 21/03/2015 12:09, Naresh Bhat wrote:
>      From 268dcdafa34a690e2f99c0784ca33a6d2352ecf5 Mon Sep 17 00:00:00 2001
>     From: Hanjun Guo <hanjun.guo@linaro.org <mailto:hanjun.guo@linaro.org>>
>     Date: Sat, 21 Mar 2015 14:43:54 +0800
>     Subject: [PATCH] XEN / ACPI: Make XEN ACPI depend on X86
>
>     When ACPI is enabled on ARM64, XEN ACPI will also compiled
>     into the kernel, but XEN ACPI is x86 dependent, so introduce
>     CONFIG_XEN_ACPI to make it depend on x86 before XEN ACPI is
>     functional on ARM64.
>
>     Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org
>     <mailto:hanjun.guo@linaro.org>>
>     ---
>       drivers/xen/Kconfig  | 4 ++++
>       drivers/xen/Makefile | 2 +-
>       2 files changed, 5 insertions(+), 1 deletion(-)
>
>     diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig
>     index b812462..a31cd29 100644
>     --- a/drivers/xen/Kconfig
>     +++ b/drivers/xen/Kconfig
>     @@ -253,4 +253,8 @@ config XEN_EFI
>           def_bool y
>           depends on X86_64 && EFI
>
>     +config XEN_ACPI
>     +    def_bool y
>     +    depends on X86 && ACPI
>     +
>       endmenu
>     diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile
>     index 2ccd359..f4622ab 100644
>     --- a/drivers/xen/Makefile
>     +++ b/drivers/xen/Makefile
>     @@ -13,7 +13,7 @@ CFLAGS_efi.o                += -fshort-wchar
>
>       dom0-$(CONFIG_PCI) += pci.o
>       dom0-$(CONFIG_USB_SUPPORT) += dbgp.o
>     -dom0-$(CONFIG_ACPI) += acpi.o $(xen-pad-y)
>     +dom0-$(CONFIG_XEN_ACPI) += acpi.o $(xen-pad-y)
>       xen-pad-$(CONFIG_X86) += xen-acpi-pad.o
>       dom0-$(CONFIG_X86) += pcpu.o
>       obj-$(CONFIG_XEN_DOM0)            += $(dom0-y)

[..]

>
> AFAIK,  There is already a kernel patch exists to fix this issue.  I
> think  Julien or Parth is a right person to ask.  Hence I am CCed Julien
> Grall too.

The ACPI support for Xen is not ready. So I think avoiding to compile 
drivers/xen/acpi.c on ARM64/ARM seems the better solution for now.

Although, rather than introducing a new CONFIG option, I would use the 
same trick we use within the Makefile to avoid hotplug.c on ARM/ARM64.

ifeq ($(filter y, $(CONFIG_ARM) $(CONFIG_ARM64)), )
dom0-$(CONFIG_ACPI) += acpi.o $(xen-pad-y)
endif

Regards,

-- 
Julien Grall