From c48d883d8bf488c1a5dc22583094e77ff53d3589 Mon Sep 17 00:00:00 2001 From: Nico Huber Date: Thu, 23 Aug 2018 22:36:09 +0200 Subject: drivers/intel/gma: Fix OpRegion Mailbox3 synchronization Make XBCM `Serialized` (obvious), and check for the callee clearing the request bit (we checked only the status for 0 which we potentially wrote ourselves). Change-Id: Ic92d525eda8d0a159fa5ddaacf230658d71c1578 Signed-off-by: Nico Huber Reviewed-on: https://review.coreboot.org/28302 Tested-by: build bot (Jenkins) Reviewed-by: Felix Held --- src/drivers/intel/gma/acpi/configure_brightness_levels.asl | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/src/drivers/intel/gma/acpi/configure_brightness_levels.asl b/src/drivers/intel/gma/acpi/configure_brightness_levels.asl index dfd878cb26..23637b0612 100644 --- a/src/drivers/intel/gma/acpi/configure_brightness_levels.asl +++ b/src/drivers/intel/gma/acpi/configure_brightness_levels.asl @@ -55,7 +55,7 @@ * * Driver not loaded or not ready * * Driver reported an error during ASLE IRQ */ - Method (XBCM, 1, NotSerialized) + Method (XBCM, 1, Serialized) { If (LEqual(ASLS, Zero)) { @@ -89,9 +89,14 @@ While (LGreater(Local0, Zero)) { Sleep (1) - If (LEqual(And(ShiftRight(ASLC, 12), 0x3), Zero)) - { - Return (Zero) + If (LEqual (And (ASLC, 0x2), 0)) { + /* Request has been processed, check status: */ + And (ShiftRight (ASLC, 12), 0x3, Local1) + If (LEqual (Local1, 0)) { + Return (Zero) + } Else { + Return (Ones) + } } Decrement (Local0) } -- cgit v1.2.3