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Diffstat (limited to 'src/drivers/intel/gma/opregion.c')
| -rw-r--r-- | src/drivers/intel/gma/opregion.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/src/drivers/intel/gma/opregion.c b/src/drivers/intel/gma/opregion.c new file mode 100644 index 0000000000..ab9093b82f --- /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); +} |