// SPDX-License-Identifier: GPL-2.0-only
// Copyright (c) 2021 Intel Corporation

#include <linux/auxiliary_bus.h>
#include <linux/module.h>
#include <linux/peci.h>
#include <linux/peci-cpu.h>
#include <linux/slab.h>

#include "internal.h"

/**
 * peci_temp_read() - read the maximum die temperature from PECI target device
 * @device: PECI device to which request is going to be sent
 * @temp_raw: where to store the read temperature
 *
 * It uses GetTemp PECI command.
 *
 * Return: 0 if succeeded, other values in case errors.
 */
int peci_temp_read(struct peci_device *device, s16 *temp_raw)
{
	struct peci_request *req;

	req = peci_xfer_get_temp(device);
	if (IS_ERR(req))
		return PTR_ERR(req);

	*temp_raw = peci_request_temp_read(req);

	peci_request_free(req);

	return 0;
}
EXPORT_SYMBOL_NS_GPL(peci_temp_read, PECI_CPU);

/**
 * peci_pcs_read() - read PCS register
 * @device: PECI device to which request is going to be sent
 * @index: PCS index
 * @param: PCS parameter
 * @data: where to store the read data
 *
 * It uses RdPkgConfig PECI command.
 *
 * Return: 0 if succeeded, other values in case errors.
 */
int peci_pcs_read(struct peci_device *device, u8 index, u16 param, u32 *data)
{
	struct peci_request *req;
	int ret;

	req = peci_xfer_pkg_cfg_readl(device, index, param);
	if (IS_ERR(req))
		return PTR_ERR(req);

	ret = peci_request_status(req);
	if (ret)
		goto out_req_free;

	*data = peci_request_data_readl(req);
out_req_free:
	peci_request_free(req);

	return ret;
}
EXPORT_SYMBOL_NS_GPL(peci_pcs_read, PECI_CPU);

/**
 * peci_pci_local_read() - read 32-bit memory location using raw address
 * @device: PECI device to which request is going to be sent
 * @bus: bus
 * @dev: device
 * @func: function
 * @reg: register
 * @data: where to store the read data
 *
 * It uses RdPCIConfigLocal PECI command.
 *
 * Return: 0 if succeeded, other values in case errors.
 */
int peci_pci_local_read(struct peci_device *device, u8 bus, u8 dev, u8 func,
			u16 reg, u32 *data)
{
	struct peci_request *req;
	int ret;

	req = peci_xfer_pci_cfg_local_readl(device, bus, dev, func, reg);
	if (IS_ERR(req))
		return PTR_ERR(req);

	ret = peci_request_status(req);
	if (ret)
		goto out_req_free;

	*data = peci_request_data_readl(req);
out_req_free:
	peci_request_free(req);

	return ret;
}
EXPORT_SYMBOL_NS_GPL(peci_pci_local_read, PECI_CPU);

/**
 * peci_ep_pci_local_read() - read 32-bit memory location using raw address
 * @device: PECI device to which request is going to be sent
 * @seg: PCI segment
 * @bus: bus
 * @dev: device
 * @func: function
 * @reg: register
 * @data: where to store the read data
 *
 * Like &peci_pci_local_read, but it uses RdEndpointConfig PECI command.
 *
 * Return: 0 if succeeded, other values in case errors.
 */
int peci_ep_pci_local_read(struct peci_device *device, u8 seg,
			   u8 bus, u8 dev, u8 func, u16 reg, u32 *data)
{
	struct peci_request *req;
	int ret;

	req = peci_xfer_ep_pci_cfg_local_readl(device, seg, bus, dev, func, reg);
	if (IS_ERR(req))
		return PTR_ERR(req);

	ret = peci_request_status(req);
	if (ret)
		goto out_req_free;

	*data = peci_request_data_readl(req);
out_req_free:
	peci_request_free(req);

	return ret;
}
EXPORT_SYMBOL_NS_GPL(peci_ep_pci_local_read, PECI_CPU);

/**
 * peci_mmio_read() - read 32-bit memory location using 64-bit bar offset address
 * @device: PECI device to which request is going to be sent
 * @bar: PCI bar
 * @seg: PCI segment
 * @bus: bus
 * @dev: device
 * @func: function
 * @address: 64-bit MMIO address
 * @data: where to store the read data
 *
 * It uses RdEndpointConfig PECI command.
 *
 * Return: 0 if succeeded, other values in case errors.
 */
int peci_mmio_read(struct peci_device *device, u8 bar, u8 seg,
		   u8 bus, u8 dev, u8 func, u64 address, u32 *data)
{
	struct peci_request *req;
	int ret;

	req = peci_xfer_ep_mmio64_readl(device, bar, seg, bus, dev, func, address);
	if (IS_ERR(req))
		return PTR_ERR(req);

	ret = peci_request_status(req);
	if (ret)
		goto out_req_free;

	*data = peci_request_data_readl(req);
out_req_free:
	peci_request_free(req);

	return ret;
}
EXPORT_SYMBOL_NS_GPL(peci_mmio_read, PECI_CPU);

static const char * const peci_adev_types[] = {
	"cputemp",
	"dimmtemp",
};

struct peci_cpu {
	struct peci_device *device;
	const struct peci_device_id *id;
};

static void adev_release(struct device *dev)
{
	struct auxiliary_device *adev = to_auxiliary_dev(dev);

	kfree(adev->name);
	kfree(adev);
}

static struct auxiliary_device *adev_alloc(struct peci_cpu *priv, int idx)
{
	struct peci_controller *controller = to_peci_controller(priv->device->dev.parent);
	struct auxiliary_device *adev;
	const char *name;
	int ret;

	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
	if (!adev)
		return ERR_PTR(-ENOMEM);

	name = kasprintf(GFP_KERNEL, "%s.%s", peci_adev_types[idx], (const char *)priv->id->data);
	if (!name) {
		ret = -ENOMEM;
		goto free_adev;
	}

	adev->name = name;
	adev->dev.parent = &priv->device->dev;
	adev->dev.release = adev_release;
	adev->id = (controller->id << 16) | (priv->device->addr);

	ret = auxiliary_device_init(adev);
	if (ret)
		goto free_name;

	return adev;

free_name:
	kfree(name);
free_adev:
	kfree(adev);
	return ERR_PTR(ret);
}

static void unregister_adev(void *_adev)
{
	struct auxiliary_device *adev = _adev;

	auxiliary_device_delete(adev);
	auxiliary_device_uninit(adev);
}

static int devm_adev_add(struct device *dev, int idx)
{
	struct peci_cpu *priv = dev_get_drvdata(dev);
	struct auxiliary_device *adev;
	int ret;

	adev = adev_alloc(priv, idx);
	if (IS_ERR(adev))
		return PTR_ERR(adev);

	ret = auxiliary_device_add(adev);
	if (ret) {
		auxiliary_device_uninit(adev);
		return ret;
	}

	ret = devm_add_action_or_reset(&priv->device->dev, unregister_adev, adev);
	if (ret)
		return ret;

	return 0;
}

static void peci_cpu_add_adevices(struct peci_cpu *priv)
{
	struct device *dev = &priv->device->dev;
	int ret, i;

	for (i = 0; i < ARRAY_SIZE(peci_adev_types); i++) {
		ret = devm_adev_add(dev, i);
		if (ret) {
			dev_warn(dev, "Failed to register PECI auxiliary: %s, ret = %d\n",
				 peci_adev_types[i], ret);
			continue;
		}
	}
}

static int
peci_cpu_probe(struct peci_device *device, const struct peci_device_id *id)
{
	struct device *dev = &device->dev;
	struct peci_cpu *priv;

	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;

	dev_set_drvdata(dev, priv);
	priv->device = device;
	priv->id = id;

	peci_cpu_add_adevices(priv);

	return 0;
}

static const struct peci_device_id peci_cpu_device_ids[] = {
	{ /* Haswell Xeon */
		.family	= 6,
		.model	= INTEL_FAM6_HASWELL_X,
		.data	= "hsx",
	},
	{ /* Broadwell Xeon */
		.family	= 6,
		.model	= INTEL_FAM6_BROADWELL_X,
		.data	= "bdx",
	},
	{ /* Broadwell Xeon D */
		.family	= 6,
		.model	= INTEL_FAM6_BROADWELL_D,
		.data	= "bdxd",
	},
	{ /* Skylake Xeon */
		.family	= 6,
		.model	= INTEL_FAM6_SKYLAKE_X,
		.data	= "skx",
	},
	{ /* Icelake Xeon */
		.family	= 6,
		.model	= INTEL_FAM6_ICELAKE_X,
		.data	= "icx",
	},
	{ /* Icelake Xeon D */
		.family	= 6,
		.model	= INTEL_FAM6_ICELAKE_D,
		.data	= "icxd",
	},
	{ }
};
MODULE_DEVICE_TABLE(peci, peci_cpu_device_ids);

static struct peci_driver peci_cpu_driver = {
	.probe		= peci_cpu_probe,
	.id_table	= peci_cpu_device_ids,
	.driver		= {
		.name		= "peci-cpu",
	},
};
module_peci_driver(peci_cpu_driver);

MODULE_AUTHOR("Iwona Winiarska <iwona.winiarska@intel.com>");
MODULE_DESCRIPTION("PECI CPU driver");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS(PECI);