early_smbus.c

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/* SPDX-License-Identifier: GPL-2.0-only */
 
#include <device/pci_def.h>
#include <device/pci_ids.h>
#include <device/pci_ops.h>
#include <device/smbus_host.h>
#include "early_smbus.h"
 
uintptr_t smbus_base(void)
{
        return CONFIG_FIXED_SMBUS_IO_BASE;
}
 
int smbus_enable_iobar(uintptr_t base)
{
        /* Set the SMBus device statically. */
        const pci_devfn_t dev = PCI_DEV_SMBUS;
 
        /* Check to make sure we've got the right device. */
        if (pci_read_config16(dev, PCI_VENDOR_ID) != PCI_VID_INTEL)
                return -1;
 
        /* Set SMBus I/O base. */
        pci_write_config32(dev, SMB_BASE, 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);
 
        return 0;
}