ACPICA: Hardware: Do not flush CPU cache when entering S4 and S5
authorKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Wed, 22 Dec 2021 16:33:51 +0000 (17:33 +0100)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Mon, 27 Dec 2021 16:01:28 +0000 (17:01 +0100)
commit1d4e0b3abb168b2ee1eca99c527cffa1b80b6161
tree3630ebea60ec4d2ba61b1ee68e7c0291bf192cd6
parent0acf24ad7e10f547809faefb8069f8f5482eb4d9
ACPICA: Hardware: Do not flush CPU cache when entering S4 and S5

ACPICA commit 3dd7e1f3996456ef81bfe14cba29860e8d42949e

According to ACPI 6.4, Section 16.2, the CPU cache flushing is
required on entering to S1, S2, and S3, but the ACPICA code
flushes the CPU cache regardless of the sleep state.

Blind cache flush on entering S5 causes problems for TDX.

Flushing happens with WBINVD that is not supported in the TDX
environment.

TDX only supports S5 and adjusting ACPICA code to conform to the
spec more strictly fixes the issue.

Link: https://github.com/acpica/acpica/commit/3dd7e1f3
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
drivers/acpi/acpica/hwesleep.c
drivers/acpi/acpica/hwsleep.c
drivers/acpi/acpica/hwxfsleep.c