// SPDX-License-Identifier: GPL-2.0
/*
 * Microsemi Switchtec(tm) PCIe Management Driver
 * Copyright (c) 2017, Microsemi Corporation
 */

#include <linux/switchtec.h>
#include <linux/switchtec_ioctl.h>

#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/uaccess.h>
#include <linux/poll.h>
#include <linux/wait.h>
#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/nospec.h>

MODULE_DESCRIPTION("Microsemi Switchtec(tm) PCIe Management Driver");
MODULE_VERSION("0.1");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Microsemi Corporation");

static int max_devices = 16;
module_param(max_devices, int, 0644);
MODULE_PARM_DESC(max_devices, "max number of switchtec device instances");

static bool use_dma_mrpc = 1;
module_param(use_dma_mrpc, bool, 0644);
MODULE_PARM_DESC(use_dma_mrpc,
		 "Enable the use of the DMA MRPC feature");

static dev_t switchtec_devt;
static DEFINE_IDA(switchtec_minor_ida);

struct class *switchtec_class;
EXPORT_SYMBOL_GPL(switchtec_class);

enum mrpc_state {
	MRPC_IDLE = 0,
	MRPC_QUEUED,
	MRPC_RUNNING,
	MRPC_DONE,
};

struct switchtec_user {
	struct switchtec_dev *stdev;

	enum mrpc_state state;

	struct completion comp;
	struct kref kref;
	struct list_head list;

	u32 cmd;
	u32 status;
	u32 return_code;
	size_t data_len;
	size_t read_len;
	unsigned char data[SWITCHTEC_MRPC_PAYLOAD_SIZE];
	int event_cnt;
};

static struct switchtec_user *stuser_create(struct switchtec_dev *stdev)
{
	struct switchtec_user *stuser;

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

	get_device(&stdev->dev);
	stuser->stdev = stdev;
	kref_init(&stuser->kref);
	INIT_LIST_HEAD(&stuser->list);
	init_completion(&stuser->comp);
	stuser->event_cnt = atomic_read(&stdev->event_cnt);

	dev_dbg(&stdev->dev, "%s: %p\n", __func__, stuser);

	return stuser;
}

static void stuser_free(struct kref *kref)
{
	struct switchtec_user *stuser;

	stuser = container_of(kref, struct switchtec_user, kref);

	dev_dbg(&stuser->stdev->dev, "%s: %p\n", __func__, stuser);

	put_device(&stuser->stdev->dev);
	kfree(stuser);
}

static void stuser_put(struct switchtec_user *stuser)
{
	kref_put(&stuser->kref, stuser_free);
}

static void stuser_set_state(struct switchtec_user *stuser,
			     enum mrpc_state state)
{
	/* requires the mrpc_mutex to already be held when called */

	const char * const state_names[] = {
		[MRPC_IDLE] = "IDLE",
		[MRPC_QUEUED] = "QUEUED",
		[MRPC_RUNNING] = "RUNNING",
		[MRPC_DONE] = "DONE",
	};

	stuser->state = state;

	dev_dbg(&stuser->stdev->dev, "stuser state %p -> %s",
		stuser, state_names[state]);
}

static void mrpc_complete_cmd(struct switchtec_dev *stdev);

static void flush_wc_buf(struct switchtec_dev *stdev)
{
	struct ntb_dbmsg_regs __iomem *mmio_dbmsg;

	/*
	 * odb (outbound doorbell) register is processed by low latency
	 * hardware and w/o side effect
	 */
	mmio_dbmsg = (void __iomem *)stdev->mmio_ntb +
		SWITCHTEC_NTB_REG_DBMSG_OFFSET;
	ioread32(&mmio_dbmsg->odb);
}

static void mrpc_cmd_submit(struct switchtec_dev *stdev)
{
	/* requires the mrpc_mutex to already be held when called */

	struct switchtec_user *stuser;

	if (stdev->mrpc_busy)
		return;

	if (list_empty(&stdev->mrpc_queue))
		return;

	stuser = list_entry(stdev->mrpc_queue.next, struct switchtec_user,
			    list);

	if (stdev->dma_mrpc) {
		stdev->dma_mrpc->status = SWITCHTEC_MRPC_STATUS_INPROGRESS;
		memset(stdev->dma_mrpc->data, 0xFF, SWITCHTEC_MRPC_PAYLOAD_SIZE);
	}

	stuser_set_state(stuser, MRPC_RUNNING);
	stdev->mrpc_busy = 1;
	memcpy_toio(&stdev->mmio_mrpc->input_data,
		    stuser->data, stuser->data_len);
	flush_wc_buf(stdev);
	iowrite32(stuser->cmd, &stdev->mmio_mrpc->cmd);

	schedule_delayed_work(&stdev->mrpc_timeout,
			      msecs_to_jiffies(500));
}

static int mrpc_queue_cmd(struct switchtec_user *stuser)
{
	/* requires the mrpc_mutex to already be held when called */

	struct switchtec_dev *stdev = stuser->stdev;

	kref_get(&stuser->kref);
	stuser->read_len = sizeof(stuser->data);
	stuser_set_state(stuser, MRPC_QUEUED);
	init_completion(&stuser->comp);
	list_add_tail(&stuser->list, &stdev->mrpc_queue);

	mrpc_cmd_submit(stdev);

	return 0;
}

static void mrpc_complete_cmd(struct switchtec_dev *stdev)
{
	/* requires the mrpc_mutex to already be held when called */
	struct switchtec_user *stuser;

	if (list_empty(&stdev->mrpc_queue))
		return;

	stuser = list_entry(stdev->mrpc_queue.next, struct switchtec_user,
			    list);

	if (stdev->dma_mrpc)
		stuser->status = stdev->dma_mrpc->status;
	else
		stuser->status = ioread32(&stdev->mmio_mrpc->status);

	if (stuser->status == SWITCHTEC_MRPC_STATUS_INPROGRESS)
		return;

	stuser_set_state(stuser, MRPC_DONE);
	stuser->return_code = 0;

	if (stuser->status != SWITCHTEC_MRPC_STATUS_DONE)
		goto out;

	if (stdev->dma_mrpc)
		stuser->return_code = stdev->dma_mrpc->rtn_code;
	else
		stuser->return_code = ioread32(&stdev->mmio_mrpc->ret_value);
	if (stuser->return_code != 0)
		goto out;

	if (stdev->dma_mrpc)
		memcpy(stuser->data, &stdev->dma_mrpc->data,
			      stuser->read_len);
	else
		memcpy_fromio(stuser->data, &stdev->mmio_mrpc->output_data,
			      stuser->read_len);
out:
	complete_all(&stuser->comp);
	list_del_init(&stuser->list);
	stuser_put(stuser);
	stdev->mrpc_busy = 0;

	mrpc_cmd_submit(stdev);
}

static void mrpc_event_work(struct work_struct *work)
{
	struct switchtec_dev *stdev;

	stdev = container_of(work, struct switchtec_dev, mrpc_work);

	dev_dbg(&stdev->dev, "%s\n", __func__);

	mutex_lock(&stdev->mrpc_mutex);
	cancel_delayed_work(&stdev->mrpc_timeout);
	mrpc_complete_cmd(stdev);
	mutex_unlock(&stdev->mrpc_mutex);
}

static void mrpc_timeout_work(struct work_struct *work)
{
	struct switchtec_dev *stdev;
	u32 status;

	stdev = container_of(work, struct switchtec_dev, mrpc_timeout.work);

	dev_dbg(&stdev->dev, "%s\n", __func__);

	mutex_lock(&stdev->mrpc_mutex);

	if (stdev->dma_mrpc)
		status = stdev->dma_mrpc->status;
	else
		status = ioread32(&stdev->mmio_mrpc->status);
	if (status == SWITCHTEC_MRPC_STATUS_INPROGRESS) {
		schedule_delayed_work(&stdev->mrpc_timeout,
				      msecs_to_jiffies(500));
		goto out;
	}

	mrpc_complete_cmd(stdev);
out:
	mutex_unlock(&stdev->mrpc_mutex);
}

static ssize_t device_version_show(struct device *dev,
	struct device_attribute *attr, char *buf)
{
	struct switchtec_dev *stdev = to_stdev(dev);
	u32 ver;

	ver = ioread32(&stdev->mmio_sys_info->device_version);

	return sprintf(buf, "%x\n", ver);
}
static DEVICE_ATTR_RO(device_version);

static ssize_t fw_version_show(struct device *dev,
	struct device_attribute *attr, char *buf)
{
	struct switchtec_dev *stdev = to_stdev(dev);
	u32 ver;

	ver = ioread32(&stdev->mmio_sys_info->firmware_version);

	return sprintf(buf, "%08x\n", ver);
}
static DEVICE_ATTR_RO(fw_version);

static ssize_t io_string_show(char *buf, void __iomem *attr, size_t len)
{
	int i;

	memcpy_fromio(buf, attr, len);
	buf[len] = '\n';
	buf[len + 1] = 0;

	for (i = len - 1; i > 0; i--) {
		if (buf[i] != ' ')
			break;
		buf[i] = '\n';
		buf[i + 1] = 0;
	}

	return strlen(buf);
}

#define DEVICE_ATTR_SYS_INFO_STR(field) \
static ssize_t field ## _show(struct device *dev, \
	struct device_attribute *attr, char *buf) \
{ \
	struct switchtec_dev *stdev = to_stdev(dev); \
	return io_string_show(buf, &stdev->mmio_sys_info->field, \
			    sizeof(stdev->mmio_sys_info->field)); \
} \
\
static DEVICE_ATTR_RO(field)

DEVICE_ATTR_SYS_INFO_STR(vendor_id);
DEVICE_ATTR_SYS_INFO_STR(product_id);
DEVICE_ATTR_SYS_INFO_STR(product_revision);
DEVICE_ATTR_SYS_INFO_STR(component_vendor);

static ssize_t component_id_show(struct device *dev,
	struct device_attribute *attr, char *buf)
{
	struct switchtec_dev *stdev = to_stdev(dev);
	int id = ioread16(&stdev->mmio_sys_info->component_id);

	return sprintf(buf, "PM%04X\n", id);
}
static DEVICE_ATTR_RO(component_id);

static ssize_t component_revision_show(struct device *dev,
	struct device_attribute *attr, char *buf)
{
	struct switchtec_dev *stdev = to_stdev(dev);
	int rev = ioread8(&stdev->mmio_sys_info->component_revision);

	return sprintf(buf, "%d\n", rev);
}
static DEVICE_ATTR_RO(component_revision);

static ssize_t partition_show(struct device *dev,
	struct device_attribute *attr, char *buf)
{
	struct switchtec_dev *stdev = to_stdev(dev);

	return sprintf(buf, "%d\n", stdev->partition);
}
static DEVICE_ATTR_RO(partition);

static ssize_t partition_count_show(struct device *dev,
	struct device_attribute *attr, char *buf)
{
	struct switchtec_dev *stdev = to_stdev(dev);

	return sprintf(buf, "%d\n", stdev->partition_count);
}
static DEVICE_ATTR_RO(partition_count);

static struct attribute *switchtec_device_attrs[] = {
	&dev_attr_device_version.attr,
	&dev_attr_fw_version.attr,
	&dev_attr_vendor_id.attr,
	&dev_attr_product_id.attr,
	&dev_attr_product_revision.attr,
	&dev_attr_component_vendor.attr,
	&dev_attr_component_id.attr,
	&dev_attr_component_revision.attr,
	&dev_attr_partition.attr,
	&dev_attr_partition_count.attr,
	NULL,
};

ATTRIBUTE_GROUPS(switchtec_device);

static int switchtec_dev_open(struct inode *inode, struct file *filp)
{
	struct switchtec_dev *stdev;
	struct switchtec_user *stuser;

	stdev = container_of(inode->i_cdev, struct switchtec_dev, cdev);

	stuser = stuser_create(stdev);
	if (IS_ERR(stuser))
		return PTR_ERR(stuser);

	filp->private_data = stuser;
	nonseekable_open(inode, filp);

	dev_dbg(&stdev->dev, "%s: %p\n", __func__, stuser);

	return 0;
}

static int switchtec_dev_release(struct inode *inode, struct file *filp)
{
	struct switchtec_user *stuser = filp->private_data;

	stuser_put(stuser);

	return 0;
}

static int lock_mutex_and_test_alive(struct switchtec_dev *stdev)
{
	if (mutex_lock_interruptible(&stdev->mrpc_mutex))
		return -EINTR;

	if (!stdev->alive) {
		mutex_unlock(&stdev->mrpc_mutex);
		return -ENODEV;
	}

	return 0;
}

static ssize_t switchtec_dev_write(struct file *filp, const char __user *data,
				   size_t size, loff_t *off)
{
	struct switchtec_user *stuser = filp->private_data;
	struct switchtec_dev *stdev = stuser->stdev;
	int rc;

	if (size < sizeof(stuser->cmd) ||
	    size > sizeof(stuser->cmd) + sizeof(stuser->data))
		return -EINVAL;

	stuser->data_len = size - sizeof(stuser->cmd);

	rc = lock_mutex_and_test_alive(stdev);
	if (rc)
		return rc;

	if (stuser->state != MRPC_IDLE) {
		rc = -EBADE;
		goto out;
	}

	rc = copy_from_user(&stuser->cmd, data, sizeof(stuser->cmd));
	if (rc) {
		rc = -EFAULT;
		goto out;
	}

	data += sizeof(stuser->cmd);
	rc = copy_from_user(&stuser->data, data, size - sizeof(stuser->cmd));
	if (rc) {
		rc = -EFAULT;
		goto out;
	}

	rc = mrpc_queue_cmd(stuser);

out:
	mutex_unlock(&stdev->mrpc_mutex);

	if (rc)
		return rc;

	return size;
}

static ssize_t switchtec_dev_read(struct file *filp, char __user *data,
				  size_t size, loff_t *off)
{
	struct switchtec_user *stuser = filp->private_data;
	struct switchtec_dev *stdev = stuser->stdev;
	int rc;

	if (size < sizeof(stuser->cmd) ||
	    size > sizeof(stuser->cmd) + sizeof(stuser->data))
		return -EINVAL;

	rc = lock_mutex_and_test_alive(stdev);
	if (rc)
		return rc;

	if (stuser->state == MRPC_IDLE) {
		mutex_unlock(&stdev->mrpc_mutex);
		return -EBADE;
	}

	stuser->read_len = size - sizeof(stuser->return_code);

	mutex_unlock(&stdev->mrpc_mutex);

	if (filp->f_flags & O_NONBLOCK) {
		if (!try_wait_for_completion(&stuser->comp))
			return -EAGAIN;
	} else {
		rc = wait_for_completion_interruptible(&stuser->comp);
		if (rc < 0)
			return rc;
	}

	rc = lock_mutex_and_test_alive(stdev);
	if (rc)
		return rc;

	if (stuser->state != MRPC_DONE) {
		mutex_unlock(&stdev->mrpc_mutex);
		return -EBADE;
	}

	rc = copy_to_user(data, &stuser->return_code,
			  sizeof(stuser->return_code));
	if (rc) {
		rc = -EFAULT;
		goto out;
	}

	data += sizeof(stuser->return_code);
	rc = copy_to_user(data, &stuser->data,
			  size - sizeof(stuser->return_code));
	if (rc) {
		rc = -EFAULT;
		goto out;
	}

	stuser_set_state(stuser, MRPC_IDLE);

out:
	mutex_unlock(&stdev->mrpc_mutex);

	if (stuser->status == SWITCHTEC_MRPC_STATUS_DONE)
		return size;
	else if (stuser->status == SWITCHTEC_MRPC_STATUS_INTERRUPTED)
		return -ENXIO;
	else
		return -EBADMSG;
}

static __poll_t switchtec_dev_poll(struct file *filp, poll_table *wait)
{
	struct switchtec_user *stuser = filp->private_data;
	struct switchtec_dev *stdev = stuser->stdev;
	__poll_t ret = 0;

	poll_wait(filp, &stuser->comp.wait, wait);
	poll_wait(filp, &stdev->event_wq, wait);

	if (lock_mutex_and_test_alive(stdev))
		return EPOLLIN | EPOLLRDHUP | EPOLLOUT | EPOLLERR | EPOLLHUP;

	mutex_unlock(&stdev->mrpc_mutex);

	if (try_wait_for_completion(&stuser->comp))
		ret |= EPOLLIN | EPOLLRDNORM;

	if (stuser->event_cnt != atomic_read(&stdev->event_cnt))
		ret |= EPOLLPRI | EPOLLRDBAND;

	return ret;
}

static int ioctl_flash_info(struct switchtec_dev *stdev,
			    struct switchtec_ioctl_flash_info __user *uinfo)
{
	struct switchtec_ioctl_flash_info info = {0};
	struct flash_info_regs __iomem *fi = stdev->mmio_flash_info;

	info.flash_length = ioread32(&fi->flash_length);
	info.num_partitions = SWITCHTEC_IOCTL_NUM_PARTITIONS;

	if (copy_to_user(uinfo, &info, sizeof(info)))
		return -EFAULT;

	return 0;
}

static void set_fw_info_part(struct switchtec_ioctl_flash_part_info *info,
			     struct partition_info __iomem *pi)
{
	info->address = ioread32(&pi->address);
	info->length = ioread32(&pi->length);
}

static int ioctl_flash_part_info(struct switchtec_dev *stdev,
	struct switchtec_ioctl_flash_part_info __user *uinfo)
{
	struct switchtec_ioctl_flash_part_info info = {0};
	struct flash_info_regs __iomem *fi = stdev->mmio_flash_info;
	struct sys_info_regs __iomem *si = stdev->mmio_sys_info;
	u32 active_addr = -1;

	if (copy_from_user(&info, uinfo, sizeof(info)))
		return -EFAULT;

	switch (info.flash_partition) {
	case SWITCHTEC_IOCTL_PART_CFG0:
		active_addr = ioread32(&fi->active_cfg);
		set_fw_info_part(&info, &fi->cfg0);
		if (ioread16(&si->cfg_running) == SWITCHTEC_CFG0_RUNNING)
			info.active |= SWITCHTEC_IOCTL_PART_RUNNING;
		break;
	case SWITCHTEC_IOCTL_PART_CFG1:
		active_addr = ioread32(&fi->active_cfg);
		set_fw_info_part(&info, &fi->cfg1);
		if (ioread16(&si->cfg_running) == SWITCHTEC_CFG1_RUNNING)
			info.active |= SWITCHTEC_IOCTL_PART_RUNNING;
		break;
	case SWITCHTEC_IOCTL_PART_IMG0:
		active_addr = ioread32(&fi->active_img);
		set_fw_info_part(&info, &fi->img0);
		if (ioread16(&si->img_running) == SWITCHTEC_IMG0_RUNNING)
			info.active |= SWITCHTEC_IOCTL_PART_RUNNING;
		break;
	case SWITCHTEC_IOCTL_PART_IMG1:
		active_addr = ioread32(&fi->active_img);
		set_fw_info_part(&info, &fi->img1);
		if (ioread16(&si->img_running) == SWITCHTEC_IMG1_RUNNING)
			info.active |= SWITCHTEC_IOCTL_PART_RUNNING;
		break;
	case SWITCHTEC_IOCTL_PART_NVLOG:
		set_fw_info_part(&info, &fi->nvlog);
		break;
	case SWITCHTEC_IOCTL_PART_VENDOR0:
		set_fw_info_part(&info, &fi->vendor[0]);
		break;
	case SWITCHTEC_IOCTL_PART_VENDOR1:
		set_fw_info_part(&info, &fi->vendor[1]);
		break;
	case SWITCHTEC_IOCTL_PART_VENDOR2:
		set_fw_info_part(&info, &fi->vendor[2]);
		break;
	case SWITCHTEC_IOCTL_PART_VENDOR3:
		set_fw_info_part(&info, &fi->vendor[3]);
		break;
	case SWITCHTEC_IOCTL_PART_VENDOR4:
		set_fw_info_part(&info, &fi->vendor[4]);
		break;
	case SWITCHTEC_IOCTL_PART_VENDOR5:
		set_fw_info_part(&info, &fi->vendor[5]);
		break;
	case SWITCHTEC_IOCTL_PART_VENDOR6:
		set_fw_info_part(&info, &fi->vendor[6]);
		break;
	case SWITCHTEC_IOCTL_PART_VENDOR7:
		set_fw_info_part(&info, &fi->vendor[7]);
		break;
	default:
		return -EINVAL;
	}

	if (info.address == active_addr)
		info.active |= SWITCHTEC_IOCTL_PART_ACTIVE;

	if (copy_to_user(uinfo, &info, sizeof(info)))
		return -EFAULT;

	return 0;
}

static int ioctl_event_summary(struct switchtec_dev *stdev,
	struct switchtec_user *stuser,
	struct switchtec_ioctl_event_summary __user *usum,
	size_t size)
{
	struct switchtec_ioctl_event_summary *s;
	int i;
	u32 reg;
	int ret = 0;

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

	s->global = ioread32(&stdev->mmio_sw_event->global_summary);
	s->part_bitmap = ioread32(&stdev->mmio_sw_event->part_event_bitmap);
	s->local_part = ioread32(&stdev->mmio_part_cfg->part_event_summary);

	for (i = 0; i < stdev->partition_count; i++) {
		reg = ioread32(&stdev->mmio_part_cfg_all[i].part_event_summary);
		s->part[i] = reg;
	}

	for (i = 0; i < SWITCHTEC_MAX_PFF_CSR; i++) {
		reg = ioread16(&stdev->mmio_pff_csr[i].vendor_id);
		if (reg != PCI_VENDOR_ID_MICROSEMI)
			break;

		reg = ioread32(&stdev->mmio_pff_csr[i].pff_event_summary);
		s->pff[i] = reg;
	}

	if (copy_to_user(usum, s, size)) {
		ret = -EFAULT;
		goto error_case;
	}

	stuser->event_cnt = atomic_read(&stdev->event_cnt);

error_case:
	kfree(s);
	return ret;
}

static u32 __iomem *global_ev_reg(struct switchtec_dev *stdev,
				  size_t offset, int index)
{
	return (void __iomem *)stdev->mmio_sw_event + offset;
}

static u32 __iomem *part_ev_reg(struct switchtec_dev *stdev,
				size_t offset, int index)
{
	return (void __iomem *)&stdev->mmio_part_cfg_all[index] + offset;
}

static u32 __iomem *pff_ev_reg(struct switchtec_dev *stdev,
			       size_t offset, int index)
{
	return (void __iomem *)&stdev->mmio_pff_csr[index] + offset;
}

#define EV_GLB(i, r)[i] = {offsetof(struct sw_event_regs, r), global_ev_reg}
#define EV_PAR(i, r)[i] = {offsetof(struct part_cfg_regs, r), part_ev_reg}
#define EV_PFF(i, r)[i] = {offsetof(struct pff_csr_regs, r), pff_ev_reg}

static const struct event_reg {
	size_t offset;
	u32 __iomem *(*map_reg)(struct switchtec_dev *stdev,
				size_t offset, int index);
} event_regs[] = {
	EV_GLB(SWITCHTEC_IOCTL_EVENT_STACK_ERROR, stack_error_event_hdr),
	EV_GLB(SWITCHTEC_IOCTL_EVENT_PPU_ERROR, ppu_error_event_hdr),
	EV_GLB(SWITCHTEC_IOCTL_EVENT_ISP_ERROR, isp_error_event_hdr),
	EV_GLB(SWITCHTEC_IOCTL_EVENT_SYS_RESET, sys_reset_event_hdr),
	EV_GLB(SWITCHTEC_IOCTL_EVENT_FW_EXC, fw_exception_hdr),
	EV_GLB(SWITCHTEC_IOCTL_EVENT_FW_NMI, fw_nmi_hdr),
	EV_GLB(SWITCHTEC_IOCTL_EVENT_FW_NON_FATAL, fw_non_fatal_hdr),
	EV_GLB(SWITCHTEC_IOCTL_EVENT_FW_FATAL, fw_fatal_hdr),
	EV_GLB(SWITCHTEC_IOCTL_EVENT_TWI_MRPC_COMP, twi_mrpc_comp_hdr),
	EV_GLB(SWITCHTEC_IOCTL_EVENT_TWI_MRPC_COMP_ASYNC,
	       twi_mrpc_comp_async_hdr),
	EV_GLB(SWITCHTEC_IOCTL_EVENT_CLI_MRPC_COMP, cli_mrpc_comp_hdr),
	EV_GLB(SWITCHTEC_IOCTL_EVENT_CLI_MRPC_COMP_ASYNC,
	       cli_mrpc_comp_async_hdr),
	EV_GLB(SWITCHTEC_IOCTL_EVENT_GPIO_INT, gpio_interrupt_hdr),
	EV_GLB(SWITCHTEC_IOCTL_EVENT_GFMS, gfms_event_hdr),
	EV_PAR(SWITCHTEC_IOCTL_EVENT_PART_RESET, part_reset_hdr),
	EV_PAR(SWITCHTEC_IOCTL_EVENT_MRPC_COMP, mrpc_comp_hdr),
	EV_PAR(SWITCHTEC_IOCTL_EVENT_MRPC_COMP_ASYNC, mrpc_comp_async_hdr),
	EV_PAR(SWITCHTEC_IOCTL_EVENT_DYN_PART_BIND_COMP, dyn_binding_hdr),
	EV_PFF(SWITCHTEC_IOCTL_EVENT_AER_IN_P2P, aer_in_p2p_hdr),
	EV_PFF(SWITCHTEC_IOCTL_EVENT_AER_IN_VEP, aer_in_vep_hdr),
	EV_PFF(SWITCHTEC_IOCTL_EVENT_DPC, dpc_hdr),
	EV_PFF(SWITCHTEC_IOCTL_EVENT_CTS, cts_hdr),
	EV_PFF(SWITCHTEC_IOCTL_EVENT_HOTPLUG, hotplug_hdr),
	EV_PFF(SWITCHTEC_IOCTL_EVENT_IER, ier_hdr),
	EV_PFF(SWITCHTEC_IOCTL_EVENT_THRESH, threshold_hdr),
	EV_PFF(SWITCHTEC_IOCTL_EVENT_POWER_MGMT, power_mgmt_hdr),
	EV_PFF(SWITCHTEC_IOCTL_EVENT_TLP_THROTTLING, tlp_throttling_hdr),
	EV_PFF(SWITCHTEC_IOCTL_EVENT_FORCE_SPEED, force_speed_hdr),
	EV_PFF(SWITCHTEC_IOCTL_EVENT_CREDIT_TIMEOUT, credit_timeout_hdr),
	EV_PFF(SWITCHTEC_IOCTL_EVENT_LINK_STATE, link_state_hdr),
};

static u32 __iomem *event_hdr_addr(struct switchtec_dev *stdev,
				   int event_id, int index)
{
	size_t off;

	if (event_id < 0 || event_id >= SWITCHTEC_IOCTL_MAX_EVENTS)
		return ERR_PTR(-EINVAL);

	off = event_regs[event_id].offset;

	if (event_regs[event_id].map_reg == part_ev_reg) {
		if (index == SWITCHTEC_IOCTL_EVENT_LOCAL_PART_IDX)
			index = stdev->partition;
		else if (index < 0 || index >= stdev->partition_count)
			return ERR_PTR(-EINVAL);
	} else if (event_regs[event_id].map_reg == pff_ev_reg) {
		if (index < 0 || index >= stdev->pff_csr_count)
			return ERR_PTR(-EINVAL);
	}

	return event_regs[event_id].map_reg(stdev, off, index);
}

static int event_ctl(struct switchtec_dev *stdev,
		     struct switchtec_ioctl_event_ctl *ctl)
{
	int i;
	u32 __iomem *reg;
	u32 hdr;

	reg = event_hdr_addr(stdev, ctl->event_id, ctl->index);
	if (IS_ERR(reg))
		return PTR_ERR(reg);

	hdr = ioread32(reg);
	for (i = 0; i < ARRAY_SIZE(ctl->data); i++)
		ctl->data[i] = ioread32(&reg[i + 1]);

	ctl->occurred = hdr & SWITCHTEC_EVENT_OCCURRED;
	ctl->count = (hdr >> 5) & 0xFF;

	if (!(ctl->flags & SWITCHTEC_IOCTL_EVENT_FLAG_CLEAR))
		hdr &= ~SWITCHTEC_EVENT_CLEAR;
	if (ctl->flags & SWITCHTEC_IOCTL_EVENT_FLAG_EN_POLL)
		hdr |= SWITCHTEC_EVENT_EN_IRQ;
	if (ctl->flags & SWITCHTEC_IOCTL_EVENT_FLAG_DIS_POLL)
		hdr &= ~SWITCHTEC_EVENT_EN_IRQ;
	if (ctl->flags & SWITCHTEC_IOCTL_EVENT_FLAG_EN_LOG)
		hdr |= SWITCHTEC_EVENT_EN_LOG;
	if (ctl->flags & SWITCHTEC_IOCTL_EVENT_FLAG_DIS_LOG)
		hdr &= ~SWITCHTEC_EVENT_EN_LOG;
	if (ctl->flags & SWITCHTEC_IOCTL_EVENT_FLAG_EN_CLI)
		hdr |= SWITCHTEC_EVENT_EN_CLI;
	if (ctl->flags & SWITCHTEC_IOCTL_EVENT_FLAG_DIS_CLI)
		hdr &= ~SWITCHTEC_EVENT_EN_CLI;
	if (ctl->flags & SWITCHTEC_IOCTL_EVENT_FLAG_EN_FATAL)
		hdr |= SWITCHTEC_EVENT_FATAL;
	if (ctl->flags & SWITCHTEC_IOCTL_EVENT_FLAG_DIS_FATAL)
		hdr &= ~SWITCHTEC_EVENT_FATAL;

	if (ctl->flags)
		iowrite32(hdr, reg);

	ctl->flags = 0;
	if (hdr & SWITCHTEC_EVENT_EN_IRQ)
		ctl->flags |= SWITCHTEC_IOCTL_EVENT_FLAG_EN_POLL;
	if (hdr & SWITCHTEC_EVENT_EN_LOG)
		ctl->flags |= SWITCHTEC_IOCTL_EVENT_FLAG_EN_LOG;
	if (hdr & SWITCHTEC_EVENT_EN_CLI)
		ctl->flags |= SWITCHTEC_IOCTL_EVENT_FLAG_EN_CLI;
	if (hdr & SWITCHTEC_EVENT_FATAL)
		ctl->flags |= SWITCHTEC_IOCTL_EVENT_FLAG_EN_FATAL;

	return 0;
}

static int ioctl_event_ctl(struct switchtec_dev *stdev,
	struct switchtec_ioctl_event_ctl __user *uctl)
{
	int ret;
	int nr_idxs;
	unsigned int event_flags;
	struct switchtec_ioctl_event_ctl ctl;

	if (copy_from_user(&ctl, uctl, sizeof(ctl)))
		return -EFAULT;

	if (ctl.event_id >= SWITCHTEC_IOCTL_MAX_EVENTS)
		return -EINVAL;

	if (ctl.flags & SWITCHTEC_IOCTL_EVENT_FLAG_UNUSED)
		return -EINVAL;

	if (ctl.index == SWITCHTEC_IOCTL_EVENT_IDX_ALL) {
		if (event_regs[ctl.event_id].map_reg == global_ev_reg)
			nr_idxs = 1;
		else if (event_regs[ctl.event_id].map_reg == part_ev_reg)
			nr_idxs = stdev->partition_count;
		else if (event_regs[ctl.event_id].map_reg == pff_ev_reg)
			nr_idxs = stdev->pff_csr_count;
		else
			return -EINVAL;

		event_flags = ctl.flags;
		for (ctl.index = 0; ctl.index < nr_idxs; ctl.index++) {
			ctl.flags = event_flags;
			ret = event_ctl(stdev, &ctl);
			if (ret < 0)
				return ret;
		}
	} else {
		ret = event_ctl(stdev, &ctl);
		if (ret < 0)
			return ret;
	}

	if (copy_to_user(uctl, &ctl, sizeof(ctl)))
		return -EFAULT;

	return 0;
}

static int ioctl_pff_to_port(struct switchtec_dev *stdev,
			     struct switchtec_ioctl_pff_port *up)
{
	int i, part;
	u32 reg;
	struct part_cfg_regs *pcfg;
	struct switchtec_ioctl_pff_port p;

	if (copy_from_user(&p, up, sizeof(p)))
		return -EFAULT;

	p.port = -1;
	for (part = 0; part < stdev->partition_count; part++) {
		pcfg = &stdev->mmio_part_cfg_all[part];
		p.partition = part;

		reg = ioread32(&pcfg->usp_pff_inst_id);
		if (reg == p.pff) {
			p.port = 0;
			break;
		}

		reg = ioread32(&pcfg->vep_pff_inst_id);
		if (reg == p.pff) {
			p.port = SWITCHTEC_IOCTL_PFF_VEP;
			break;
		}

		for (i = 0; i < ARRAY_SIZE(pcfg->dsp_pff_inst_id); i++) {
			reg = ioread32(&pcfg->dsp_pff_inst_id[i]);
			if (reg != p.pff)
				continue;

			p.port = i + 1;
			break;
		}

		if (p.port != -1)
			break;
	}

	if (copy_to_user(up, &p, sizeof(p)))
		return -EFAULT;

	return 0;
}

static int ioctl_port_to_pff(struct switchtec_dev *stdev,
			     struct switchtec_ioctl_pff_port *up)
{
	struct switchtec_ioctl_pff_port p;
	struct part_cfg_regs *pcfg;

	if (copy_from_user(&p, up, sizeof(p)))
		return -EFAULT;

	if (p.partition == SWITCHTEC_IOCTL_EVENT_LOCAL_PART_IDX)
		pcfg = stdev->mmio_part_cfg;
	else if (p.partition < stdev->partition_count)
		pcfg = &stdev->mmio_part_cfg_all[p.partition];
	else
		return -EINVAL;

	switch (p.port) {
	case 0:
		p.pff = ioread32(&pcfg->usp_pff_inst_id);
		break;
	case SWITCHTEC_IOCTL_PFF_VEP:
		p.pff = ioread32(&pcfg->vep_pff_inst_id);
		break;
	default:
		if (p.port > ARRAY_SIZE(pcfg->dsp_pff_inst_id))
			return -EINVAL;
		p.port = array_index_nospec(p.port,
					ARRAY_SIZE(pcfg->dsp_pff_inst_id) + 1);
		p.pff = ioread32(&pcfg->dsp_pff_inst_id[p.port - 1]);
		break;
	}

	if (copy_to_user(up, &p, sizeof(p)))
		return -EFAULT;

	return 0;
}

static long switchtec_dev_ioctl(struct file *filp, unsigned int cmd,
				unsigned long arg)
{
	struct switchtec_user *stuser = filp->private_data;
	struct switchtec_dev *stdev = stuser->stdev;
	int rc;
	void __user *argp = (void __user *)arg;

	rc = lock_mutex_and_test_alive(stdev);
	if (rc)
		return rc;

	switch (cmd) {
	case SWITCHTEC_IOCTL_FLASH_INFO:
		rc = ioctl_flash_info(stdev, argp);
		break;
	case SWITCHTEC_IOCTL_FLASH_PART_INFO:
		rc = ioctl_flash_part_info(stdev, argp);
		break;
	case SWITCHTEC_IOCTL_EVENT_SUMMARY_LEGACY:
		rc = ioctl_event_summary(stdev, stuser, argp,
					 sizeof(struct switchtec_ioctl_event_summary_legacy));
		break;
	case SWITCHTEC_IOCTL_EVENT_CTL:
		rc = ioctl_event_ctl(stdev, argp);
		break;
	case SWITCHTEC_IOCTL_PFF_TO_PORT:
		rc = ioctl_pff_to_port(stdev, argp);
		break;
	case SWITCHTEC_IOCTL_PORT_TO_PFF:
		rc = ioctl_port_to_pff(stdev, argp);
		break;
	case SWITCHTEC_IOCTL_EVENT_SUMMARY:
		rc = ioctl_event_summary(stdev, stuser, argp,
					 sizeof(struct switchtec_ioctl_event_summary));
		break;
	default:
		rc = -ENOTTY;
		break;
	}

	mutex_unlock(&stdev->mrpc_mutex);
	return rc;
}

static const struct file_operations switchtec_fops = {
	.owner = THIS_MODULE,
	.open = switchtec_dev_open,
	.release = switchtec_dev_release,
	.write = switchtec_dev_write,
	.read = switchtec_dev_read,
	.poll = switchtec_dev_poll,
	.unlocked_ioctl = switchtec_dev_ioctl,
	.compat_ioctl = switchtec_dev_ioctl,
};

static void link_event_work(struct work_struct *work)
{
	struct switchtec_dev *stdev;

	stdev = container_of(work, struct switchtec_dev, link_event_work);

	if (stdev->link_notifier)
		stdev->link_notifier(stdev);
}

static void check_link_state_events(struct switchtec_dev *stdev)
{
	int idx;
	u32 reg;
	int count;
	int occurred = 0;

	for (idx = 0; idx < stdev->pff_csr_count; idx++) {
		reg = ioread32(&stdev->mmio_pff_csr[idx].link_state_hdr);
		dev_dbg(&stdev->dev, "link_state: %d->%08x\n", idx, reg);
		count = (reg >> 5) & 0xFF;

		if (count != stdev->link_event_count[idx]) {
			occurred = 1;
			stdev->link_event_count[idx] = count;
		}
	}

	if (occurred)
		schedule_work(&stdev->link_event_work);
}

static void enable_link_state_events(struct switchtec_dev *stdev)
{
	int idx;

	for (idx = 0; idx < stdev->pff_csr_count; idx++) {
		iowrite32(SWITCHTEC_EVENT_CLEAR |
			  SWITCHTEC_EVENT_EN_IRQ,
			  &stdev->mmio_pff_csr[idx].link_state_hdr);
	}
}

static void enable_dma_mrpc(struct switchtec_dev *stdev)
{
	writeq(stdev->dma_mrpc_dma_addr, &stdev->mmio_mrpc->dma_addr);
	flush_wc_buf(stdev);
	iowrite32(SWITCHTEC_DMA_MRPC_EN, &stdev->mmio_mrpc->dma_en);
}

static void stdev_release(struct device *dev)
{
	struct switchtec_dev *stdev = to_stdev(dev);

	if (stdev->dma_mrpc) {
		iowrite32(0, &stdev->mmio_mrpc->dma_en);
		flush_wc_buf(stdev);
		writeq(0, &stdev->mmio_mrpc->dma_addr);
		dma_free_coherent(&stdev->pdev->dev, sizeof(*stdev->dma_mrpc),
				stdev->dma_mrpc, stdev->dma_mrpc_dma_addr);
	}
	kfree(stdev);
}

static void stdev_kill(struct switchtec_dev *stdev)
{
	struct switchtec_user *stuser, *tmpuser;

	pci_clear_master(stdev->pdev);

	cancel_delayed_work_sync(&stdev->mrpc_timeout);

	/* Mark the hardware as unavailable and complete all completions */
	mutex_lock(&stdev->mrpc_mutex);
	stdev->alive = false;

	/* Wake up and kill any users waiting on an MRPC request */
	list_for_each_entry_safe(stuser, tmpuser, &stdev->mrpc_queue, list) {
		complete_all(&stuser->comp);
		list_del_init(&stuser->list);
		stuser_put(stuser);
	}

	mutex_unlock(&stdev->mrpc_mutex);

	/* Wake up any users waiting on event_wq */
	wake_up_interruptible(&stdev->event_wq);
}

static struct switchtec_dev *stdev_create(struct pci_dev *pdev)
{
	struct switchtec_dev *stdev;
	int minor;
	struct device *dev;
	struct cdev *cdev;
	int rc;

	stdev = kzalloc_node(sizeof(*stdev), GFP_KERNEL,
			     dev_to_node(&pdev->dev));
	if (!stdev)
		return ERR_PTR(-ENOMEM);

	stdev->alive = true;
	stdev->pdev = pdev;
	INIT_LIST_HEAD(&stdev->mrpc_queue);
	mutex_init(&stdev->mrpc_mutex);
	stdev->mrpc_busy = 0;
	INIT_WORK(&stdev->mrpc_work, mrpc_event_work);
	INIT_DELAYED_WORK(&stdev->mrpc_timeout, mrpc_timeout_work);
	INIT_WORK(&stdev->link_event_work, link_event_work);
	init_waitqueue_head(&stdev->event_wq);
	atomic_set(&stdev->event_cnt, 0);

	dev = &stdev->dev;
	device_initialize(dev);
	dev->class = switchtec_class;
	dev->parent = &pdev->dev;
	dev->groups = switchtec_device_groups;
	dev->release = stdev_release;

	minor = ida_simple_get(&switchtec_minor_ida, 0, 0,
			       GFP_KERNEL);
	if (minor < 0) {
		rc = minor;
		goto err_put;
	}

	dev->devt = MKDEV(MAJOR(switchtec_devt), minor);
	dev_set_name(dev, "switchtec%d", minor);

	cdev = &stdev->cdev;
	cdev_init(cdev, &switchtec_fops);
	cdev->owner = THIS_MODULE;

	return stdev;

err_put:
	put_device(&stdev->dev);
	return ERR_PTR(rc);
}

static int mask_event(struct switchtec_dev *stdev, int eid, int idx)
{
	size_t off = event_regs[eid].offset;
	u32 __iomem *hdr_reg;
	u32 hdr;

	hdr_reg = event_regs[eid].map_reg(stdev, off, idx);
	hdr = ioread32(hdr_reg);

	if (!(hdr & SWITCHTEC_EVENT_OCCURRED && hdr & SWITCHTEC_EVENT_EN_IRQ))
		return 0;

	if (eid == SWITCHTEC_IOCTL_EVENT_LINK_STATE)
		return 0;

	dev_dbg(&stdev->dev, "%s: %d %d %x\n", __func__, eid, idx, hdr);
	hdr &= ~(SWITCHTEC_EVENT_EN_IRQ | SWITCHTEC_EVENT_OCCURRED);
	iowrite32(hdr, hdr_reg);

	return 1;
}

static int mask_all_events(struct switchtec_dev *stdev, int eid)
{
	int idx;
	int count = 0;

	if (event_regs[eid].map_reg == part_ev_reg) {
		for (idx = 0; idx < stdev->partition_count; idx++)
			count += mask_event(stdev, eid, idx);
	} else if (event_regs[eid].map_reg == pff_ev_reg) {
		for (idx = 0; idx < stdev->pff_csr_count; idx++) {
			if (!stdev->pff_local[idx])
				continue;

			count += mask_event(stdev, eid, idx);
		}
	} else {
		count += mask_event(stdev, eid, 0);
	}

	return count;
}

static irqreturn_t switchtec_event_isr(int irq, void *dev)
{
	struct switchtec_dev *stdev = dev;
	u32 reg;
	irqreturn_t ret = IRQ_NONE;
	int eid, event_count = 0;

	reg = ioread32(&stdev->mmio_part_cfg->mrpc_comp_hdr);
	if (reg & SWITCHTEC_EVENT_OCCURRED) {
		dev_dbg(&stdev->dev, "%s: mrpc comp\n", __func__);
		ret = IRQ_HANDLED;
		schedule_work(&stdev->mrpc_work);
		iowrite32(reg, &stdev->mmio_part_cfg->mrpc_comp_hdr);
	}

	check_link_state_events(stdev);

	for (eid = 0; eid < SWITCHTEC_IOCTL_MAX_EVENTS; eid++)
		event_count += mask_all_events(stdev, eid);

	if (event_count) {
		atomic_inc(&stdev->event_cnt);
		wake_up_interruptible(&stdev->event_wq);
		dev_dbg(&stdev->dev, "%s: %d events\n", __func__,
			event_count);
		return IRQ_HANDLED;
	}

	return ret;
}


static irqreturn_t switchtec_dma_mrpc_isr(int irq, void *dev)
{
	struct switchtec_dev *stdev = dev;
	irqreturn_t ret = IRQ_NONE;

	iowrite32(SWITCHTEC_EVENT_CLEAR |
		  SWITCHTEC_EVENT_EN_IRQ,
		  &stdev->mmio_part_cfg->mrpc_comp_hdr);
	schedule_work(&stdev->mrpc_work);

	ret = IRQ_HANDLED;
	return ret;
}

static int switchtec_init_isr(struct switchtec_dev *stdev)
{
	int nvecs;
	int event_irq;
	int dma_mrpc_irq;
	int rc;

	nvecs = pci_alloc_irq_vectors(stdev->pdev, 1, 4,
				      PCI_IRQ_MSIX | PCI_IRQ_MSI);
	if (nvecs < 0)
		return nvecs;

	event_irq = ioread32(&stdev->mmio_part_cfg->vep_vector_number);
	if (event_irq < 0 || event_irq >= nvecs)
		return -EFAULT;

	event_irq = pci_irq_vector(stdev->pdev, event_irq);
	if (event_irq < 0)
		return event_irq;

	rc = devm_request_irq(&stdev->pdev->dev, event_irq,
				switchtec_event_isr, 0,
				KBUILD_MODNAME, stdev);

	if (rc)
		return rc;

	if (!stdev->dma_mrpc)
		return rc;

	dma_mrpc_irq = ioread32(&stdev->mmio_mrpc->dma_vector);
	if (dma_mrpc_irq < 0 || dma_mrpc_irq >= nvecs)
		return -EFAULT;

	dma_mrpc_irq  = pci_irq_vector(stdev->pdev, dma_mrpc_irq);
	if (dma_mrpc_irq < 0)
		return dma_mrpc_irq;

	rc = devm_request_irq(&stdev->pdev->dev, dma_mrpc_irq,
				switchtec_dma_mrpc_isr, 0,
				KBUILD_MODNAME, stdev);

	return rc;
}

static void init_pff(struct switchtec_dev *stdev)
{
	int i;
	u32 reg;
	struct part_cfg_regs *pcfg = stdev->mmio_part_cfg;

	for (i = 0; i < SWITCHTEC_MAX_PFF_CSR; i++) {
		reg = ioread16(&stdev->mmio_pff_csr[i].vendor_id);
		if (reg != PCI_VENDOR_ID_MICROSEMI)
			break;
	}

	stdev->pff_csr_count = i;

	reg = ioread32(&pcfg->usp_pff_inst_id);
	if (reg < SWITCHTEC_MAX_PFF_CSR)
		stdev->pff_local[reg] = 1;

	reg = ioread32(&pcfg->vep_pff_inst_id);
	if (reg < SWITCHTEC_MAX_PFF_CSR)
		stdev->pff_local[reg] = 1;

	for (i = 0; i < ARRAY_SIZE(pcfg->dsp_pff_inst_id); i++) {
		reg = ioread32(&pcfg->dsp_pff_inst_id[i]);
		if (reg < SWITCHTEC_MAX_PFF_CSR)
			stdev->pff_local[reg] = 1;
	}
}

static int switchtec_init_pci(struct switchtec_dev *stdev,
			      struct pci_dev *pdev)
{
	int rc;
	void __iomem *map;
	unsigned long res_start, res_len;

	rc = pcim_enable_device(pdev);
	if (rc)
		return rc;

	rc = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64));
	if (rc)
		return rc;

	pci_set_master(pdev);

	res_start = pci_resource_start(pdev, 0);
	res_len = pci_resource_len(pdev, 0);

	if (!devm_request_mem_region(&pdev->dev, res_start,
				     res_len, KBUILD_MODNAME))
		return -EBUSY;

	stdev->mmio_mrpc = devm_ioremap_wc(&pdev->dev, res_start,
					   SWITCHTEC_GAS_TOP_CFG_OFFSET);
	if (!stdev->mmio_mrpc)
		return -ENOMEM;

	map = devm_ioremap(&pdev->dev,
			   res_start + SWITCHTEC_GAS_TOP_CFG_OFFSET,
			   res_len - SWITCHTEC_GAS_TOP_CFG_OFFSET);
	if (!map)
		return -ENOMEM;

	stdev->mmio = map - SWITCHTEC_GAS_TOP_CFG_OFFSET;
	stdev->mmio_sw_event = stdev->mmio + SWITCHTEC_GAS_SW_EVENT_OFFSET;
	stdev->mmio_sys_info = stdev->mmio + SWITCHTEC_GAS_SYS_INFO_OFFSET;
	stdev->mmio_flash_info = stdev->mmio + SWITCHTEC_GAS_FLASH_INFO_OFFSET;
	stdev->mmio_ntb = stdev->mmio + SWITCHTEC_GAS_NTB_OFFSET;
	stdev->partition = ioread8(&stdev->mmio_sys_info->partition_id);
	stdev->partition_count = ioread8(&stdev->mmio_ntb->partition_count);
	stdev->mmio_part_cfg_all = stdev->mmio + SWITCHTEC_GAS_PART_CFG_OFFSET;
	stdev->mmio_part_cfg = &stdev->mmio_part_cfg_all[stdev->partition];
	stdev->mmio_pff_csr = stdev->mmio + SWITCHTEC_GAS_PFF_CSR_OFFSET;

	if (stdev->partition_count < 1)
		stdev->partition_count = 1;

	init_pff(stdev);

	pci_set_drvdata(pdev, stdev);

	if (!use_dma_mrpc)
		return 0;

	if (ioread32(&stdev->mmio_mrpc->dma_ver) == 0)
		return 0;

	stdev->dma_mrpc = dma_alloc_coherent(&stdev->pdev->dev,
					     sizeof(*stdev->dma_mrpc),
					     &stdev->dma_mrpc_dma_addr,
					     GFP_KERNEL);
	if (stdev->dma_mrpc == NULL)
		return -ENOMEM;

	return 0;
}

static int switchtec_pci_probe(struct pci_dev *pdev,
			       const struct pci_device_id *id)
{
	struct switchtec_dev *stdev;
	int rc;

	if (pdev->class == (PCI_CLASS_BRIDGE_OTHER << 8))
		request_module_nowait("ntb_hw_switchtec");

	stdev = stdev_create(pdev);
	if (IS_ERR(stdev))
		return PTR_ERR(stdev);

	rc = switchtec_init_pci(stdev, pdev);
	if (rc)
		goto err_put;

	rc = switchtec_init_isr(stdev);
	if (rc) {
		dev_err(&stdev->dev, "failed to init isr.\n");
		goto err_put;
	}

	iowrite32(SWITCHTEC_EVENT_CLEAR |
		  SWITCHTEC_EVENT_EN_IRQ,
		  &stdev->mmio_part_cfg->mrpc_comp_hdr);
	enable_link_state_events(stdev);

	if (stdev->dma_mrpc)
		enable_dma_mrpc(stdev);

	rc = cdev_device_add(&stdev->cdev, &stdev->dev);
	if (rc)
		goto err_devadd;

	dev_info(&stdev->dev, "Management device registered.\n");

	return 0;

err_devadd:
	stdev_kill(stdev);
err_put:
	ida_simple_remove(&switchtec_minor_ida, MINOR(stdev->dev.devt));
	put_device(&stdev->dev);
	return rc;
}

static void switchtec_pci_remove(struct pci_dev *pdev)
{
	struct switchtec_dev *stdev = pci_get_drvdata(pdev);

	pci_set_drvdata(pdev, NULL);

	cdev_device_del(&stdev->cdev, &stdev->dev);
	ida_simple_remove(&switchtec_minor_ida, MINOR(stdev->dev.devt));
	dev_info(&stdev->dev, "unregistered.\n");
	stdev_kill(stdev);
	put_device(&stdev->dev);
}

#define SWITCHTEC_PCI_DEVICE(device_id) \
	{ \
		.vendor     = PCI_VENDOR_ID_MICROSEMI, \
		.device     = device_id, \
		.subvendor  = PCI_ANY_ID, \
		.subdevice  = PCI_ANY_ID, \
		.class      = (PCI_CLASS_MEMORY_OTHER << 8), \
		.class_mask = 0xFFFFFFFF, \
	}, \
	{ \
		.vendor     = PCI_VENDOR_ID_MICROSEMI, \
		.device     = device_id, \
		.subvendor  = PCI_ANY_ID, \
		.subdevice  = PCI_ANY_ID, \
		.class      = (PCI_CLASS_BRIDGE_OTHER << 8), \
		.class_mask = 0xFFFFFFFF, \
	}

static const struct pci_device_id switchtec_pci_tbl[] = {
	SWITCHTEC_PCI_DEVICE(0x8531),  //PFX 24xG3
	SWITCHTEC_PCI_DEVICE(0x8532),  //PFX 32xG3
	SWITCHTEC_PCI_DEVICE(0x8533),  //PFX 48xG3
	SWITCHTEC_PCI_DEVICE(0x8534),  //PFX 64xG3
	SWITCHTEC_PCI_DEVICE(0x8535),  //PFX 80xG3
	SWITCHTEC_PCI_DEVICE(0x8536),  //PFX 96xG3
	SWITCHTEC_PCI_DEVICE(0x8541),  //PSX 24xG3
	SWITCHTEC_PCI_DEVICE(0x8542),  //PSX 32xG3
	SWITCHTEC_PCI_DEVICE(0x8543),  //PSX 48xG3
	SWITCHTEC_PCI_DEVICE(0x8544),  //PSX 64xG3
	SWITCHTEC_PCI_DEVICE(0x8545),  //PSX 80xG3
	SWITCHTEC_PCI_DEVICE(0x8546),  //PSX 96xG3
	SWITCHTEC_PCI_DEVICE(0x8551),  //PAX 24XG3
	SWITCHTEC_PCI_DEVICE(0x8552),  //PAX 32XG3
	SWITCHTEC_PCI_DEVICE(0x8553),  //PAX 48XG3
	SWITCHTEC_PCI_DEVICE(0x8554),  //PAX 64XG3
	SWITCHTEC_PCI_DEVICE(0x8555),  //PAX 80XG3
	SWITCHTEC_PCI_DEVICE(0x8556),  //PAX 96XG3
	SWITCHTEC_PCI_DEVICE(0x8561),  //PFXL 24XG3
	SWITCHTEC_PCI_DEVICE(0x8562),  //PFXL 32XG3
	SWITCHTEC_PCI_DEVICE(0x8563),  //PFXL 48XG3
	SWITCHTEC_PCI_DEVICE(0x8564),  //PFXL 64XG3
	SWITCHTEC_PCI_DEVICE(0x8565),  //PFXL 80XG3
	SWITCHTEC_PCI_DEVICE(0x8566),  //PFXL 96XG3
	SWITCHTEC_PCI_DEVICE(0x8571),  //PFXI 24XG3
	SWITCHTEC_PCI_DEVICE(0x8572),  //PFXI 32XG3
	SWITCHTEC_PCI_DEVICE(0x8573),  //PFXI 48XG3
	SWITCHTEC_PCI_DEVICE(0x8574),  //PFXI 64XG3
	SWITCHTEC_PCI_DEVICE(0x8575),  //PFXI 80XG3
	SWITCHTEC_PCI_DEVICE(0x8576),  //PFXI 96XG3
	{0}
};
MODULE_DEVICE_TABLE(pci, switchtec_pci_tbl);

static struct pci_driver switchtec_pci_driver = {
	.name		= KBUILD_MODNAME,
	.id_table	= switchtec_pci_tbl,
	.probe		= switchtec_pci_probe,
	.remove		= switchtec_pci_remove,
};

static int __init switchtec_init(void)
{
	int rc;

	rc = alloc_chrdev_region(&switchtec_devt, 0, max_devices,
				 "switchtec");
	if (rc)
		return rc;

	switchtec_class = class_create(THIS_MODULE, "switchtec");
	if (IS_ERR(switchtec_class)) {
		rc = PTR_ERR(switchtec_class);
		goto err_create_class;
	}

	rc = pci_register_driver(&switchtec_pci_driver);
	if (rc)
		goto err_pci_register;

	pr_info(KBUILD_MODNAME ": loaded.\n");

	return 0;

err_pci_register:
	class_destroy(switchtec_class);

err_create_class:
	unregister_chrdev_region(switchtec_devt, max_devices);

	return rc;
}
module_init(switchtec_init);

static void __exit switchtec_exit(void)
{
	pci_unregister_driver(&switchtec_pci_driver);
	class_destroy(switchtec_class);
	unregister_chrdev_region(switchtec_devt, max_devices);
	ida_destroy(&switchtec_minor_ida);

	pr_info(KBUILD_MODNAME ": unloaded.\n");
}
module_exit(switchtec_exit);