[tip:x86/mm] acpi: Introduce acpi_arch_get_root_pointer() for getting rsdp address

From: tip-bot for Juergen Gross
Date: Mon Feb 26 2018 - 03:46:54 EST


Commit-ID: dfc9327ab7c99bc13e12106448615efba833886b
Gitweb: https://git.kernel.org/tip/dfc9327ab7c99bc13e12106448615efba833886b
Author: Juergen Gross <jgross@xxxxxxxx>
AuthorDate: Mon, 19 Feb 2018 11:09:04 +0100
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Mon, 26 Feb 2018 08:43:20 +0100

acpi: Introduce acpi_arch_get_root_pointer() for getting rsdp address

Add an architecture specific function to get the address of the RSDP
table. Per default it will just return 0 indicating falling back to
the current mechanism.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Acked-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Eric Biederman <ebiederm@xxxxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: boris.ostrovsky@xxxxxxxxxx
Cc: lenb@xxxxxxxxxx
Cc: linux-acpi@xxxxxxxxxxxxxxx
Cc: xen-devel@xxxxxxxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/20180219100906.14265-2-jgross@xxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
drivers/acpi/osl.c | 5 ++++-
include/linux/acpi.h | 7 +++++++
2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 3bb46cb24a99..7ca41bf023c9 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -189,12 +189,15 @@ early_param("acpi_rsdp", setup_acpi_rsdp);

acpi_physical_address __init acpi_os_get_root_pointer(void)
{
- acpi_physical_address pa = 0;
+ acpi_physical_address pa;

#ifdef CONFIG_KEXEC
if (acpi_rsdp)
return acpi_rsdp;
#endif
+ pa = acpi_arch_get_root_pointer();
+ if (pa)
+ return pa;

if (efi_enabled(EFI_CONFIG_TABLES)) {
if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 968173ec2726..15bfb15c2fa5 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -623,6 +623,13 @@ bool acpi_gtdt_c3stop(int type);
int acpi_arch_timer_mem_init(struct arch_timer_mem *timer_mem, int *timer_count);
#endif

+#ifndef ACPI_HAVE_ARCH_GET_ROOT_POINTER
+static inline u64 acpi_arch_get_root_pointer(void)
+{
+ return 0;
+}
+#endif
+
#else /* !CONFIG_ACPI */

#define acpi_disabled 1