From mboxrd@z Thu Jan 1 00:00:00 1970 From: julien.grall@linaro.org (Julien Grall) Date: Sun, 22 Mar 2015 21:32:48 +0000 Subject: [PATCH v10 00/21] Introduce ACPI for ARM64 based on ACPI 5.1 In-Reply-To: <2189259.UNlTC1BNmt@vostro.rjw.lan> References: <1426077587-1561-1-git-send-email-hanjun.guo@linaro.org> <550F2E91.7010109@linaro.org> <2189259.UNlTC1BNmt@vostro.rjw.lan> Message-ID: <550F3500.1040608@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 22/03/2015 21:49, Rafael J. Wysocki wrote: > On Sunday, March 22, 2015 09:05:21 PM Julien Grall wrote: >> Hello, >> >> On 21/03/2015 12:09, Naresh Bhat wrote: >>> From 268dcdafa34a690e2f99c0784ca33a6d2352ecf5 Mon Sep 17 00:00:00 2001 >>> From: Hanjun Guo > >>> 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 >> > >>> --- >>> 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 > > Well, is avoiding an extra CONFIG_ option worth the ugliness of this? When the support of ACPI for Xen will come, the CONFIG_ option will be an alias to CONFIG_XEN. In this case the CONFIG_ option won't bring much improvement to the code and add an extra indirection. The "ugliness" option has, at least, the advantage to be tiny and self-contained. Regards, -- Julien Grall