diff options
Diffstat (limited to 'src/soc/intel/common/block/i2c/i2c_early.c')
-rw-r--r-- | src/soc/intel/common/block/i2c/i2c_early.c | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/src/soc/intel/common/block/i2c/i2c_early.c b/src/soc/intel/common/block/i2c/i2c_early.c new file mode 100644 index 0000000000..7c9ce60513 --- /dev/null +++ b/src/soc/intel/common/block/i2c/i2c_early.c @@ -0,0 +1,97 @@ +/* + * This file is part of the coreboot project. + * + * Copyright 2016 Google Inc. + * Copyright 2017 Intel Corporation. + * + * 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/device.h> +#include <device/i2c.h> +#include <device/pci.h> +#include <device/pci_def.h> +#include <intelblocks/lpss.h> +#include <intelblocks/lpss_i2c.h> +#include "lpss_i2c.h" + +static int lpss_i2c_early_init_bus(unsigned int bus) +{ + const struct lpss_i2c_bus_config *config; + const struct device *tree_dev; + pci_devfn_t dev; + int devfn; + uintptr_t base; + + /* Find the PCI device for this bus controller */ + devfn = i2c_soc_bus_to_devfn(bus); + if (devfn < 0) { + printk(BIOS_ERR, "I2C%u device not found\n", bus); + return -1; + } + + /* Look up the controller device in the devicetree */ + dev = PCI_DEV(0, PCI_SLOT(devfn), PCI_FUNC(devfn)); + tree_dev = dev_find_slot(0, devfn); + if (!tree_dev || !tree_dev->enabled) { + printk(BIOS_ERR, "I2C%u device not enabled\n", bus); + return -1; + } + + /* Skip if not enabled for early init */ + config = i2c_get_soc_cfg(bus, tree_dev); + if (!config || !config->early_init) { + printk(BIOS_DEBUG, "I2C%u not enabled for early init\n", bus); + return -1; + } + + /* Prepare early base address for access before memory */ + base = i2c_get_soc_early_base(bus); + pci_write_config32(dev, PCI_BASE_ADDRESS_0, base); + pci_write_config32(dev, PCI_COMMAND, + PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER); + + /* Take device out of reset */ + lpss_reset_release(base); + + /* Initialize the controller */ + if (lpss_i2c_init(bus, config) < 0) { + printk(BIOS_ERR, "I2C%u failed to initialize\n", bus); + return -1; + } + + return 0; +} + +uintptr_t lpss_i2c_base_address(unsigned int bus) +{ + int devfn; + pci_devfn_t dev; + uintptr_t base; + + /* Find device+function for this controller */ + devfn = i2c_soc_bus_to_devfn(bus); + if (devfn < 0) + return (uintptr_t)NULL; + + /* Form a PCI address for this device */ + dev = PCI_DEV(0, PCI_SLOT(devfn), PCI_FUNC(devfn)); + + /* Read the first base address for this device */ + base = ALIGN_DOWN(pci_read_config32(dev, PCI_BASE_ADDRESS_0), 16); + + /* Attempt to initialize bus if base is not set yet */ + if (!base && !lpss_i2c_early_init_bus(bus)) + base = ALIGN_DOWN(pci_read_config32(dev, PCI_BASE_ADDRESS_0), + 16); + return base; +} |