On Thursday, March 05, 2015 12:25:54 AM Rafael J. Wysocki wrote:
On Wednesday, March 04, 2015 10:49:25 PM G Gregory wrote:
On 4 March 2015 at 22:38, Rafael J. Wysocki rjw@rjwysocki.net wrote:
On Wednesday, February 25, 2015 04:39:47 PM Hanjun Guo wrote:
From: Graeme Gregory graeme.gregory@linaro.org
ACPI 5.1 does not currently support S states for ARM64 hardware but ACPI code will call acpi_target_system_state() for device power management, so introduce acpi_sleep.c to allow other drivers to function until S states are defined.
Since it is arm64 specific stub holder, so let acpi_sleep.c to ARM64 specific.
TODO: merge this with drivers/acpi/sleep.c once we fix the specification.
CC: Rafael J. Wysocki rjw@rjwysocki.net Tested-by: Suravee Suthikulpanit Suravee.Suthikulpanit@amd.com Tested-by: Yijing Wang wangyijing@huawei.com Tested-by: Mark Langsdorf mlangsdo@redhat.com Tested-by: Jon Masters jcm@redhat.com Tested-by: Timur Tabi timur@codeaurora.org Tested-by: Robert Richter rrichter@cavium.com Acked-by: Robert Richter rrichter@cavium.com Signed-off-by: Graeme Gregory graeme.gregory@linaro.org Signed-off-by: Tomasz Nowicki tomasz.nowicki@linaro.org Signed-off-by: Hanjun Guo hanjun.guo@linaro.org
arch/arm64/kernel/Makefile | 2 +- arch/arm64/kernel/acpi_sleep.c | 28 ++++++++++++++++++++++++++++ drivers/acpi/Makefile | 2 ++ 3 files changed, 31 insertions(+), 1 deletion(-) create mode 100644 arch/arm64/kernel/acpi_sleep.c
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index 218eb7e..4435943 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -34,7 +34,7 @@ arm64-obj-$(CONFIG_KGDB) += kgdb.o arm64-obj-$(CONFIG_EFI) += efi.o efi-stub.o efi-entry.o arm64-obj-$(CONFIG_PCI) += pci.o arm64-obj-$(CONFIG_ARMV8_DEPRECATED) += armv8_deprecated.o -arm64-obj-$(CONFIG_ACPI) += acpi.o +arm64-obj-$(CONFIG_ACPI) += acpi.o acpi_sleep.o
obj-y += $(arm64-obj-y) vdso/ obj-m += $(arm64-obj-m) diff --git a/arch/arm64/kernel/acpi_sleep.c b/arch/arm64/kernel/acpi_sleep.c new file mode 100644 index 0000000..54578ef --- /dev/null +++ b/arch/arm64/kernel/acpi_sleep.c @@ -0,0 +1,28 @@ +/*
- ARM64 Specific Sleep Functionality
- Copyright (C) 2013-2014, Linaro Ltd.
Author: Graeme Gregory <graeme.gregory@linaro.org>
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License version 2 as
- published by the Free Software Foundation.
- */
+#include <linux/acpi.h>
+/*
- Currently the ACPI 5.1 standard does not define S states in a
- manner which is usable for ARM64. These two stubs are sufficient
- that system initialises and device PM works.
- */
+u32 acpi_target_system_state(void) +{
return ACPI_STATE_S0;+} +EXPORT_SYMBOL_GPL(acpi_target_system_state);
+int __init acpi_sleep_init(void) +{
return -ENOSYS;+} diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index 623b117..c32edf5 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -23,7 +23,9 @@ acpi-y += nvs.o
# Power management related files acpi-y += wakeup.o +ifneq (,$(findstring $(ARCH),x86 ia64))
This is super-ugly. Isn't there a better way to do that?
Its the standard example in the GNU Make manual,
It is never used in the kernel this way, though, and I'm not going to let that slip through.
I would certainly love if someone had a batter suggestion.
Define ACPI_GENERIC_SLEEP in drivers/acpi/Kconfig as
config ACPI_GENERIC_SLEEP bool depends on IA64 || X86
and build the file conditional on that.
Or define
config ACPI_GENERIC_SLEEP bool
and then make both x86 and ia64 do
select ACPI_GENERIC_SLEEP if ACPI
which kind of will make it clear where the choice takes place.