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authorDenis 'GNUtoo' Carikli <GNUtoo@no-log.org>2013-03-28 14:24:39 +0100
committerRonald G. Minnich <rminnich@gmail.com>2013-04-18 02:48:02 +0200
commit4b213a8d1fd02061c1e879ff98167bcb47f13bd2 (patch)
tree215a6f770ba95890c174b8b403d00ca7414481c2 /src/northbridge
parentab348528b58e987994eb783a7622404515a18cd8 (diff)
downloadcoreboot-4b213a8d1fd02061c1e879ff98167bcb47f13bd2.tar.xz
Intel i945: ACPI: Add _OSC method
Add the ACPI Operating System Capabilities Method and let the operation system control everything. Commit »AMD Fam14 DSDT: Add OSC method« (00a0e76b) [1] is used as a template. The Lenovo X60 [2] running the Parabola GNU/Linux distribution [3] is used for testing. Before that change: $ dmesg | egrep -e OSC -e ASPM [ 0.108036] pci_root PNP0A08:00: ACPI _OSC support notification failed, disabling PCIe ASPM [ 0.108040] pci_root PNP0A08:00: Unable to request _OSC control (_OSC support mask: 0x08) [ 0.118089] ACPI _OSC control for PCIe not granted, disabling ASPM [ 16.874569] e1000e 0000:01:00.0: Disabling ASPM L0s L1 With that change: $ dmesg | egrep -e OSC -e ASPM [ 0.107962] pci_root PNP0A08:00: Requesting ACPI _OSC control (0x1d) [ 0.108003] pci_root PNP0A08:00: ACPI _OSC control (0x1d) granted [ 0.111052] pci 0000:01:00.0: disabling ASPM on pre-1.1 PCIe device. You can enable it with 'pcie_aspm=force' [ 17.537970] e1000e 0000:01:00.0: Disabling ASPM L0s L1 [1] http://review.coreboot.org/2738 [2] http://www.coreboot.org/Lenovo_x60x [3] https://parabolagnulinux.org/ Change-Id: I1caffa44eea447d553c01caaf431f2db241ea5ea Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@no-log.org> Signed-off-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-on: http://review.coreboot.org/2938 Tested-by: build bot (Jenkins) Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Diffstat (limited to 'src/northbridge')
-rw-r--r--src/northbridge/intel/i945/acpi/i945.asl19
1 files changed, 19 insertions, 0 deletions
diff --git a/src/northbridge/intel/i945/acpi/i945.asl b/src/northbridge/intel/i945/acpi/i945.asl
index 47a6931c67..6a34b94535 100644
--- a/src/northbridge/intel/i945/acpi/i945.asl
+++ b/src/northbridge/intel/i945/acpi/i945.asl
@@ -22,6 +22,25 @@
#include "hostbridge.asl"
#include "../i945.h"
+/* Operating System Capabilities Method */
+Method (_OSC, 4)
+{
+ // Create DWord-addressable fields from the Capabilities Buffer
+ CreateDWordField(Arg3, 0, CDW1)
+ CreateDWordField(Arg3, 4, CDW2)
+ CreateDWordField(Arg3, 8, CDW3)
+
+ /* Check for proper PCI/PCIe UUID */
+ If (LEqual(Arg0, ToUUID("33DB4D5B-1FF7-401C-9657-7441C03DD766")))
+ {
+ /* Let OS control everything */
+ Return(Arg3)
+ } Else {
+ Or(CDW1, 4, CDW1) // Unrecognized UUID, so set bit 2 to 1
+ Return(Arg3)
+ }
+}
+
/* PCI Device Resource Consumption */
Device (PDRC)
{