From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Date: Mon, 6 Dec 2021 15:29:52 +0300
Subject: ACPI: PM: Avoid CPU cache flush when entering S4
Patch-mainline: v5.17-rc1
Git-commit: 53d01e2016d77ff647fb2056c39c67df18ee86bf
References: jsc#PED-1408

According to ACPI 6.4, Section 16.2, the CPU cache flushing is
required on entering to S1, S2, and S3.

No need to flush the caches during hibernation (S4).

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>
Acked-by: Lee, Chun-Yi <jlee@suse.com>
---
 drivers/acpi/sleep.c |    2 --
 1 file changed, 2 deletions(-)

--- a/drivers/acpi/sleep.c
+++ b/drivers/acpi/sleep.c
@@ -903,8 +903,6 @@ static int acpi_hibernation_enter(void)
 {
 	acpi_status status = AE_OK;
 
-	ACPI_FLUSH_CPU_CACHE();
-
 	/* This shouldn't return.  If it returns, we have a problem */
 	status = acpi_enter_sleep_state(ACPI_STATE_S4);
 	/* Reprogram control registers */