drv/intel/gma/opregion: Add function to set ASLS register
Add a new method to set ASLS register that holds the
ACPI OpRegion base address.
Change-Id: I4850500ac6d58f80b0eddc81514053c87774405c
Signed-off-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-on: https://review.coreboot.org/20281
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
diff --git a/src/drivers/intel/gma/opregion.c b/src/drivers/intel/gma/opregion.c
new file mode 100644
index 0000000..ab9093b
--- /dev/null
+++ b/src/drivers/intel/gma/opregion.c
@@ -0,0 +1,48 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2017 Patrick Rudolph <siro@das-labor.org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; version 2, or (at your option)
+ * any later verion of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <device/device.h>
+#include <device/pci.h>
+#include <device/pci_ids.h>
+#include <device/pci_ops.h>
+#include "opregion.h"
+
+/* Write ASLS PCI register and prepare SWSCI register. */
+void intel_gma_opregion_register(uintptr_t opregion)
+{
+ device_t igd;
+ u16 reg16;
+
+ igd = dev_find_slot(0, PCI_DEVFN(0x2, 0));
+ if (!igd || !igd->enabled)
+ return;
+
+ /*
+ * Intel BIOS Specification
+ * Chapter 5.3.7 "Initialize Hardware State"
+ */
+ pci_write_config32(igd, ASLS, opregion);
+
+ /*
+ * Intel's Windows driver relies on this:
+ * Intel BIOS Specification
+ * Chapter 5.4 "ASL Software SCI Handler"
+ */
+ reg16 = pci_read_config16(igd, SWSCI);
+ reg16 &= ~GSSCIE;
+ reg16 |= SMISCISEL;
+ pci_write_config16(igd, SWSCI, reg16);
+}