diff options
Diffstat (limited to 'src/soc/intel/sch/early_smbus.c')
-rw-r--r-- | src/soc/intel/sch/early_smbus.c | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/src/soc/intel/sch/early_smbus.c b/src/soc/intel/sch/early_smbus.c new file mode 100644 index 0000000000..2f9cdeb060 --- /dev/null +++ b/src/soc/intel/sch/early_smbus.c @@ -0,0 +1,57 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2008-2009 coresystems GmbH + * + * 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 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 <arch/io.h> +#include <console/console.h> +#include <device/pci_ids.h> +#include <device/pci_def.h> +#include "i82801gx.h" +#include "smbus.h" + +void enable_smbus(void) +{ + device_t dev; + + /* Set the SMBus device statically. */ + dev = PCI_DEV(0x0, 0x1f, 0x3); + + /* Check to make sure we've got the right device. */ + if (pci_read_config16(dev, 0x2) != 0x27da) { + die("SMBus controller not found!"); + } + + /* Set SMBus I/O base. */ + pci_write_config32(dev, SMB_BASE, + SMBUS_IO_BASE | PCI_BASE_ADDRESS_SPACE_IO); + + /* Set SMBus enable. */ + pci_write_config8(dev, HOSTC, HST_EN); + + /* Set SMBus I/O space enable. */ + pci_write_config16(dev, PCI_COMMAND, PCI_COMMAND_IO); + + /* Disable interrupt generation. */ + outb(0, SMBUS_IO_BASE + SMBHSTCTL); + + /* Clear any lingering errors, so transactions can run. */ + outb(inb(SMBUS_IO_BASE + SMBHSTSTAT), SMBUS_IO_BASE + SMBHSTSTAT); + printk(BIOS_DEBUG, "SMBus controller enabled.\n"); +} + +int smbus_read_byte(unsigned device, unsigned address) +{ + return do_smbus_read_byte(SMBUS_IO_BASE, device, address); +} |