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authorDmitry Torokhov <dmitry.torokhov@gmail.com>2019-07-20 07:07:56 +0300
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2019-07-20 07:07:56 +0300
commitc39f2d9db0fd81ea20bb5cce9b3f082ca63753e2 (patch)
tree8e80ed5601b4fb8880a2ca8e08802bc8b1f850bd /arch/x86/kernel/acpi/cstate.c
parentMerge branch 'next' into for-linus (diff)
parentInput: alps - fix a mismatch between a condition check and its comment (diff)
downloadlinux-dev-c39f2d9db0fd81ea20bb5cce9b3f082ca63753e2.tar.xz
linux-dev-c39f2d9db0fd81ea20bb5cce9b3f082ca63753e2.zip
Merge branch 'next' into for-linus
Prepare second round of input updates for 5.3 merge window.
Diffstat (limited to 'arch/x86/kernel/acpi/cstate.c')
-rw-r--r--arch/x86/kernel/acpi/cstate.c13
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/x86/kernel/acpi/cstate.c b/arch/x86/kernel/acpi/cstate.c
index 158ad1483c43..a5e5484988fd 100644
--- a/arch/x86/kernel/acpi/cstate.c
+++ b/arch/x86/kernel/acpi/cstate.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2005 Intel Corporation
* Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
@@ -51,6 +52,18 @@ void acpi_processor_power_init_bm_check(struct acpi_processor_flags *flags,
if (c->x86_vendor == X86_VENDOR_INTEL &&
(c->x86 > 0xf || (c->x86 == 6 && c->x86_model >= 0x0f)))
flags->bm_control = 0;
+ /*
+ * For all recent Centaur CPUs, the ucode will make sure that each
+ * core can keep cache coherence with each other while entering C3
+ * type state. So, set bm_check to 1 to indicate that the kernel
+ * doesn't need to execute a cache flush operation (WBINVD) when
+ * entering C3 type state.
+ */
+ if (c->x86_vendor == X86_VENDOR_CENTAUR) {
+ if (c->x86 > 6 || (c->x86 == 6 && c->x86_model == 0x0f &&
+ c->x86_stepping >= 0x0e))
+ flags->bm_check = 1;
+ }
}
EXPORT_SYMBOL(acpi_processor_power_init_bm_check);