[PATCH v5 05/14] x86, ACPI: move ACPI_FADT_NO_CMOS_RTC check to ACPI boot code

Luis R. Rodriguez
2016-04-08T23:40:55Z

This moves the ACPI specific check into the ACPI boot code,
it also takes advantage of the x86_platform.legacy.rtc which
is checked for already on the RTC initialization code. This
lets us remove the nasty #ifdefery and consolidate the checks
to use only one toggle to disable the RTC init code.

The works as RTC is initialized by device_initcall(add_rtc_cmos),
this will run late in boot on start_kernel() during rest_init(),
acpi_parse_fadt() gets called earlier during setup_arch().

Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
---
arch/x86/kernel/acpi/boot.c | 4 ++++
arch/x86/kernel/rtc.c | 8 --------
2 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 8c2f1ef6ca23..8c9c2bdba092 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -913,6 +913,10 @@ late_initcall(hpet_insert_resource);

static int __init acpi_parse_fadt(struct acpi_table_header *table)
{
+ if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_CMOS_RTC) {
+ pr_debug("ACPI: not registering RTC platform device\n");
+ x86_platform.legacy.rtc = 0;
+ }

#ifdef CONFIG_X86_PM_TIMER
/* detect the location of the ACPI PM Timer */
diff --git a/arch/x86/kernel/rtc.c b/arch/x86/kernel/rtc.c
index 62c48da3889d..ff4f4180fefd 100644
--- a/arch/x86/kernel/rtc.c
+++ b/arch/x86/kernel/rtc.c
@@ -189,14 +189,6 @@ static __init int add_rtc_cmos(void)
if (of_have_populated_dt())
return 0;

-#ifdef CONFIG_ACPI
- if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_CMOS_RTC) {
- /* This warning can likely go away again in a year or two. */
- pr_info("ACPI: not registering RTC platform device\n");
- return -ENODEV;
- }
-#endif
-
if (!x86_platform.legacy.rtc)
return -ENODEV;

--
2.7.2