From deeec18520f4c8ccdd53abbbdb07a13b7f3124bf Mon Sep 17 00:00:00 2001 From: Nico Huber Date: Thu, 27 Aug 2015 13:31:46 +0200 Subject: gma ACPI: Do not overwrite backlight configuration Changes to CR1 and CR2 were effectively overwriting the backlight configuration from the devicetree with static values. Instead read the maximum brightness value from BCLM (backlight modulation frequency) and calculate the target level (Arg0 is the target level as percentage). Turned out that _BQC has to return a value from the list returned by _BCL. So XBQC got a little heavier to search for the correct value. Change-Id: I35419993c8250c95fc69ba4db30db9dba9e6f8ff Signed-off-by: Nico Huber Reviewed-on: http://review.coreboot.org/11704 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc Reviewed-by: Paul Menzel Reviewed-by: Vladimir Serbinenko --- src/drivers/intel/gma/acpi/brightness_levels.asl | 23 +++++++++++++++++------ src/drivers/intel/gma/acpi/non-pch.asl | 2 -- src/drivers/intel/gma/acpi/pch.asl | 2 -- 3 files changed, 17 insertions(+), 10 deletions(-) (limited to 'src') diff --git a/src/drivers/intel/gma/acpi/brightness_levels.asl b/src/drivers/intel/gma/acpi/brightness_levels.asl index c186989fda..d0e70a9418 100644 --- a/src/drivers/intel/gma/acpi/brightness_levels.asl +++ b/src/drivers/intel/gma/acpi/brightness_levels.asl @@ -22,14 +22,25 @@ Method (XBCM, 1, NotSerialized) { - Store (ShiftLeft (Arg0, 4), BCLV) - Store (0x80000000, CR1) - Store (0x0610, BCLM) + Store (Divide (Multiply (Arg0, BCLM), 100), BCLV) } Method (XBQC, 0, NotSerialized) { - Store (BCLV, Local0) - ShiftRight (Local0, 4, Local0) - Return (Local0) + /* Find value close to BCLV in BRIG (which must be ordered) */ + Store (BCLV, Local0) // Current value + Store (BCLM, Local1) // For calculations + Store (2, Local2) // Loop index + While (LLess (Local2, Subtract (SizeOf (BRIG), 1))) { + Store (DeRefOf (Index (BRIG, Local2)), Local3) + /* Use same calculation as XBCM, to get exact matches */ + Store (Divide (Multiply (Local3, Local1), 100), Local3) + + If (LLessEqual (Local0, Local3)) { + Return (DeRefOf (Index (BRIG, Local2))) + } + Add (Local2, 1, Local2) + } + /* Didn't find greater/equal value: use the last */ + Return (DeRefOf (Index (BRIG, Local2))) } diff --git a/src/drivers/intel/gma/acpi/non-pch.asl b/src/drivers/intel/gma/acpi/non-pch.asl index c445c97c8c..0e156272b1 100644 --- a/src/drivers/intel/gma/acpi/non-pch.asl +++ b/src/drivers/intel/gma/acpi/non-pch.asl @@ -32,8 +32,6 @@ Device (GFX0) OperationRegion (GFRG, SystemMemory, And (BAR0, 0xfffffffffffffff0), 0x400000) Field (GFRG, DWordAcc, NoLock, Preserve) { - Offset (0x61250), - CR1, 32, Offset (0x61254), BCLV, 16, BCLM, 16, diff --git a/src/drivers/intel/gma/acpi/pch.asl b/src/drivers/intel/gma/acpi/pch.asl index 0a6b5834b9..98746e809d 100644 --- a/src/drivers/intel/gma/acpi/pch.asl +++ b/src/drivers/intel/gma/acpi/pch.asl @@ -34,8 +34,6 @@ Device (GFX0) { Offset (0x48254), BCLV, 16, - Offset (0xc8250), - CR1, 32, Offset (0xc8256), BCLM, 16 } -- cgit v1.2.3