ACPI: Work around IASL warning reading/writing same register
The newer versions of IASL are unhappy when an operator
has the same object as both source and destination.
The warning can be completely disabled with a command
line argument, but in general, I'd really rather not
just disable warnings.
The bits in this register are write 1 to clear, so reading and
writing the same register is what we want to do. Instead, store
it in a temporary register then write it in a second operation.
Fixes warning:
dsdt.aml 1396: Store(PWST, PWST)
Warning 3023 - ^ Duplicate value in list
(Source is the same as Target)
Change-Id: I52d73d4431db237be83016d67cd397f31b53d9c6
Signed-off-by: Martin Roth <martinroth@google.com>
Reviewed-on: https://review.coreboot.org/12691
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
diff --git a/src/mainboard/lippert/frontrunner-af/dsdt.asl b/src/mainboard/lippert/frontrunner-af/dsdt.asl
index eaac895..9e3b39c 100644
--- a/src/mainboard/lippert/frontrunner-af/dsdt.asl
+++ b/src/mainboard/lippert/frontrunner-af/dsdt.asl
@@ -925,7 +925,8 @@
}
/* Arbitrarily clear PciExpWakeStatus */
- Store(PWST, PWST)
+ Store(PWST, Local1)
+ Store(Local1, PWST)
/* if(DeRefOf(Index(WKST,0))) {
* Store(0, Index(WKST,1))