[SeaBIOS] [PATCH] ACPI DSDT: Make control method `IQCR` serialized

[Paul Menzel]

Date: Thu, 3 Oct 2013 11:30:52 +0200

The ASL Optimizing Compiler version 20130823-32 [Sep 11 2013] issues the
following warning.

        $ make
        […]
          Compiling IASL out/src/fw/acpi-dsdt.hex
        out/src/fw/acpi-dsdt.dsl.i    360:         Method(IQCR, 1, NotSerialized) {
        Remark   2120 -                                     ^ Control Method should be made Serialized (due to creation of named objects within)
        […]
        ASL Input:     out/src/fw/acpi-dsdt.dsl.i - 475 lines, 19181 bytes, 316 keywords
        AML Output:    out/src/fw/acpi-dsdt.aml - 4407 bytes, 159 named objects, 157 executable opcodes
        Listing File:  out/src/fw/acpi-dsdt.lst - 143715 bytes
        Hex Dump:      out/src/fw/acpi-dsdt.hex - 41661 bytes

        Compilation complete. 0 Errors, 0 Warnings, 1 Remarks, 246 Optimizations
        […]

After changing the parameter from `NotSerialized` to `Serialized`, the
remark is indeed gone and there is no size change.

The remark was added in ACPICA version 20130517 [1] and gives the
following explanation.

        If a thread blocks within the method for any reason, and another thread
        enters the method, the method will fail because an attempt will be
        made to create the same (named) object twice.

        In this case, issue a remark that the method should be marked
        serialized. ACPICA BZ 909.

[1] https://github.com/acpica/acpica/commit/ba84d0fc18ba910a47a3f71c68a43543c06e6831

Signed-off-by: Paul Menzel <paulepanter at users.sourceforge.net>
---
 src/fw/acpi-dsdt.dsl     | 2 +-
 src/fw/q35-acpi-dsdt.dsl | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/fw/acpi-dsdt.dsl b/src/fw/acpi-dsdt.dsl
index 158f6b4..56243c3 100644
--- a/src/fw/acpi-dsdt.dsl
+++ b/src/fw/acpi-dsdt.dsl
@@ -235,7 +235,7 @@ DefinitionBlock (
             }
             Return (0x0B)
         }
-        Method(IQCR, 1, NotSerialized) {
+        Method(IQCR, 1, Serialized) {
             // _CRS method - get current settings
             Name(PRR0, ResourceTemplate() {
                 Interrupt(, Level, ActiveHigh, Shared) { 0 }
diff --git a/src/fw/q35-acpi-dsdt.dsl b/src/fw/q35-acpi-dsdt.dsl
index c031d83..5dec541 100644
--- a/src/fw/q35-acpi-dsdt.dsl
+++ b/src/fw/q35-acpi-dsdt.dsl
@@ -331,7 +331,7 @@ DefinitionBlock (
             }
             Return (0x0B)
         }
-        Method(IQCR, 1, NotSerialized) {
+        Method(IQCR, 1, Serialized) {
             // _CRS method - get current settings
             Name(PRR0, ResourceTemplate() {
                 Interrupt(, Level, ActiveHigh, Shared) { 0 }
-- 
1.8.4.rc3
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