From 9c3d112bb686f1c044aeb501ef810e2fb8c9310e Mon Sep 17 00:00:00 2001 From: Mike Loptien Date: Fri, 15 Mar 2013 13:22:32 -0600 Subject: ASROCK Fam14 DSDT: Add OSC method The _OSC method is used to tell the OS what capabilities it can take control over from the firmware. This method is described in chapter 6.2.9 of the ACPI spec v3.0. The method takes 4 inputs (UUID, Rev ID, Input Count, and Capabilities Buffer) and returns a Capabilites Buffer the same size as the input Buffer. This Buffer is generally 3 Dwords long consisting of an Errors Dword, a Supported Capabilities Dword, and a Control Dword. The OS will request control of certain capabilities and the firmware must grant or deny control of those features. We do not want to have control over anything so let the OS control as much as it can. The _OSC method is required for PCIe devices and dmesg checks for its existence and issues an error if it is not found. This is the same change made to Persimmon with Change-ID I149428: http://review.coreboot.org/#/c/2684/ Change-Id: I2701d915338294bdade2ad334b22a51db980892e Signed-off-by: Mike Loptien Reviewed-on: http://review.coreboot.org/2739 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer --- src/mainboard/asrock/e350m1/dsdt.asl | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) (limited to 'src') diff --git a/src/mainboard/asrock/e350m1/dsdt.asl b/src/mainboard/asrock/e350m1/dsdt.asl index bc4543516a..feec7c9cd5 100644 --- a/src/mainboard/asrock/e350m1/dsdt.asl +++ b/src/mainboard/asrock/e350m1/dsdt.asl @@ -1157,8 +1157,20 @@ DefinitionBlock ( Device(PCI0) { External (TOM1) External (TOM2) - Name(_HID, EISAID("PNP0A03")) + Name(_HID, EISAID("PNP0A08")) /* PCI Express Root Bridge */ + Name(_CID, EISAID("PNP0A03")) /* PCI Root Bridge */ Name(_ADR, 0x00180000) /* Dev# = BSP Dev#, Func# = 0 */ + + /* Operating System Capabilities Method */ + Method(_OSC,4) + { /* Check for proper PCI/PCIe UUID */ + If(LEqual(Arg0,ToUUID("33DB4D5B-1FF7-401C-9657-7441C03DD766"))) + { + /* Let OS control everything */ + Return (Arg3) + } + } + Method(_BBN, 0) { /* Bus number = 0 */ Return(0) } -- cgit v1.2.3