// SPDX-License-Identifier: (BSD-3-Clause OR GPL-2.0-only)
/* Copyright(c) 2014 - 2020 Intel Corporation */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include "adf_accel_devices.h"
#include "adf_common_drv.h"
#include "adf_cfg.h"
#include "adf_cfg_strings.h"
#include "adf_cfg_common.h"
#include "adf_transport_access_macros.h"
#include "adf_transport_internal.h"

#define ADF_MAX_NUM_VFS	32
static struct workqueue_struct *adf_misc_wq;

static int adf_enable_msix(struct adf_accel_dev *accel_dev)
{
	struct adf_accel_pci *pci_dev_info = &accel_dev->accel_pci_dev;
	struct adf_hw_device_data *hw_data = accel_dev->hw_device;
	u32 msix_num_entries = hw_data->num_banks + 1;
	int ret;

	if (hw_data->set_msix_rttable)
		hw_data->set_msix_rttable(accel_dev);

	ret = pci_alloc_irq_vectors(pci_dev_info->pci_dev, msix_num_entries,
				    msix_num_entries, PCI_IRQ_MSIX);
	if (unlikely(ret < 0)) {
		dev_err(&GET_DEV(accel_dev),
			"Failed to allocate %d MSI-X vectors\n",
			msix_num_entries);
		return ret;
	}
	return 0;
}

static void adf_disable_msix(struct adf_accel_pci *pci_dev_info)
{
	pci_free_irq_vectors(pci_dev_info->pci_dev);
}

static irqreturn_t adf_msix_isr_bundle(int irq, void *bank_ptr)
{
	struct adf_etr_bank_data *bank = bank_ptr;
	struct adf_hw_csr_ops *csr_ops = GET_CSR_OPS(bank->accel_dev);

	csr_ops->write_csr_int_flag_and_col(bank->csr_addr, bank->bank_number,
					    0);
	tasklet_hi_schedule(&bank->resp_handler);
	return IRQ_HANDLED;
}

#ifdef CONFIG_PCI_IOV
void adf_enable_vf2pf_interrupts(struct adf_accel_dev *accel_dev, u32 vf_mask)
{
	void __iomem *pmisc_addr = adf_get_pmisc_base(accel_dev);
	unsigned long flags;

	spin_lock_irqsave(&accel_dev->pf.vf2pf_ints_lock, flags);
	GET_PFVF_OPS(accel_dev)->enable_vf2pf_interrupts(pmisc_addr, vf_mask);
	spin_unlock_irqrestore(&accel_dev->pf.vf2pf_ints_lock, flags);
}

void adf_disable_vf2pf_interrupts(struct adf_accel_dev *accel_dev, u32 vf_mask)
{
	void __iomem *pmisc_addr = adf_get_pmisc_base(accel_dev);
	unsigned long flags;

	spin_lock_irqsave(&accel_dev->pf.vf2pf_ints_lock, flags);
	GET_PFVF_OPS(accel_dev)->disable_vf2pf_interrupts(pmisc_addr, vf_mask);
	spin_unlock_irqrestore(&accel_dev->pf.vf2pf_ints_lock, flags);
}

static void adf_disable_vf2pf_interrupts_irq(struct adf_accel_dev *accel_dev,
					     u32 vf_mask)
{
	void __iomem *pmisc_addr = adf_get_pmisc_base(accel_dev);

	spin_lock(&accel_dev->pf.vf2pf_ints_lock);
	GET_PFVF_OPS(accel_dev)->disable_vf2pf_interrupts(pmisc_addr, vf_mask);
	spin_unlock(&accel_dev->pf.vf2pf_ints_lock);
}

static bool adf_handle_vf2pf_int(struct adf_accel_dev *accel_dev)
{
	void __iomem *pmisc_addr = adf_get_pmisc_base(accel_dev);
	bool irq_handled = false;
	unsigned long vf_mask;

	/* Get the interrupt sources triggered by VFs */
	vf_mask = GET_PFVF_OPS(accel_dev)->get_vf2pf_sources(pmisc_addr);

	if (vf_mask) {
		struct adf_accel_vf_info *vf_info;
		int i;

		/* Disable VF2PF interrupts for VFs with pending ints */
		adf_disable_vf2pf_interrupts_irq(accel_dev, vf_mask);

		/*
		 * Handle VF2PF interrupt unless the VF is malicious and
		 * is attempting to flood the host OS with VF2PF interrupts.
		 */
		for_each_set_bit(i, &vf_mask, ADF_MAX_NUM_VFS) {
			vf_info = accel_dev->pf.vf_info + i;

			if (!__ratelimit(&vf_info->vf2pf_ratelimit)) {
				dev_info(&GET_DEV(accel_dev),
					 "Too many ints from VF%d\n",
					  vf_info->vf_nr);
				continue;
			}

			adf_schedule_vf2pf_handler(vf_info);
			irq_handled = true;
		}
	}
	return irq_handled;
}
#endif /* CONFIG_PCI_IOV */

static bool adf_handle_pm_int(struct adf_accel_dev *accel_dev)
{
	struct adf_hw_device_data *hw_data = accel_dev->hw_device;

	if (hw_data->handle_pm_interrupt &&
	    hw_data->handle_pm_interrupt(accel_dev))
		return true;

	return false;
}

static irqreturn_t adf_msix_isr_ae(int irq, void *dev_ptr)
{
	struct adf_accel_dev *accel_dev = dev_ptr;

#ifdef CONFIG_PCI_IOV
	/* If SR-IOV is enabled (vf_info is non-NULL), check for VF->PF ints */
	if (accel_dev->pf.vf_info && adf_handle_vf2pf_int(accel_dev))
		return IRQ_HANDLED;
#endif /* CONFIG_PCI_IOV */

	if (adf_handle_pm_int(accel_dev))
		return IRQ_HANDLED;

	dev_dbg(&GET_DEV(accel_dev), "qat_dev%d spurious AE interrupt\n",
		accel_dev->accel_id);

	return IRQ_NONE;
}

static void adf_free_irqs(struct adf_accel_dev *accel_dev)
{
	struct adf_accel_pci *pci_dev_info = &accel_dev->accel_pci_dev;
	struct adf_hw_device_data *hw_data = accel_dev->hw_device;
	struct adf_irq *irqs = pci_dev_info->msix_entries.irqs;
	struct adf_etr_data *etr_data = accel_dev->transport;
	int clust_irq = hw_data->num_banks;
	int irq, i = 0;

	if (pci_dev_info->msix_entries.num_entries > 1) {
		for (i = 0; i < hw_data->num_banks; i++) {
			if (irqs[i].enabled) {
				irq = pci_irq_vector(pci_dev_info->pci_dev, i);
				irq_set_affinity_hint(irq, NULL);
				free_irq(irq, &etr_data->banks[i]);
			}
		}
	}

	if (irqs[i].enabled) {
		irq = pci_irq_vector(pci_dev_info->pci_dev, clust_irq);
		free_irq(irq, accel_dev);
	}
}

static int adf_request_irqs(struct adf_accel_dev *accel_dev)
{
	struct adf_accel_pci *pci_dev_info = &accel_dev->accel_pci_dev;
	struct adf_hw_device_data *hw_data = accel_dev->hw_device;
	struct adf_irq *irqs = pci_dev_info->msix_entries.irqs;
	struct adf_etr_data *etr_data = accel_dev->transport;
	int clust_irq = hw_data->num_banks;
	int ret, irq, i = 0;
	char *name;

	/* Request msix irq for all banks unless SR-IOV enabled */
	if (!accel_dev->pf.vf_info) {
		for (i = 0; i < hw_data->num_banks; i++) {
			struct adf_etr_bank_data *bank = &etr_data->banks[i];
			unsigned int cpu, cpus = num_online_cpus();

			name = irqs[i].name;
			snprintf(name, ADF_MAX_MSIX_VECTOR_NAME,
				 "qat%d-bundle%d", accel_dev->accel_id, i);
			irq = pci_irq_vector(pci_dev_info->pci_dev, i);
			if (unlikely(irq < 0)) {
				dev_err(&GET_DEV(accel_dev),
					"Failed to get IRQ number of device vector %d - %s\n",
					i, name);
				ret = irq;
				goto err;
			}
			ret = request_irq(irq, adf_msix_isr_bundle, 0,
					  &name[0], bank);
			if (ret) {
				dev_err(&GET_DEV(accel_dev),
					"Failed to allocate IRQ %d for %s\n",
					irq, name);
				goto err;
			}

			cpu = ((accel_dev->accel_id * hw_data->num_banks) +
			       i) % cpus;
			irq_set_affinity_hint(irq, get_cpu_mask(cpu));
			irqs[i].enabled = true;
		}
	}

	/* Request msix irq for AE */
	name = irqs[i].name;
	snprintf(name, ADF_MAX_MSIX_VECTOR_NAME,
		 "qat%d-ae-cluster", accel_dev->accel_id);
	irq = pci_irq_vector(pci_dev_info->pci_dev, clust_irq);
	if (unlikely(irq < 0)) {
		dev_err(&GET_DEV(accel_dev),
			"Failed to get IRQ number of device vector %d - %s\n",
			i, name);
		ret = irq;
		goto err;
	}
	ret = request_irq(irq, adf_msix_isr_ae, 0, &name[0], accel_dev);
	if (ret) {
		dev_err(&GET_DEV(accel_dev),
			"Failed to allocate IRQ %d for %s\n", irq, name);
		goto err;
	}
	irqs[i].enabled = true;
	return ret;
err:
	adf_free_irqs(accel_dev);
	return ret;
}

static int adf_isr_alloc_msix_vectors_data(struct adf_accel_dev *accel_dev)
{
	struct adf_hw_device_data *hw_data = accel_dev->hw_device;
	u32 msix_num_entries = 1;
	struct adf_irq *irqs;

	/* If SR-IOV is disabled (vf_info is NULL), add entries for each bank */
	if (!accel_dev->pf.vf_info)
		msix_num_entries += hw_data->num_banks;

	irqs = kzalloc_node(msix_num_entries * sizeof(*irqs),
			    GFP_KERNEL, dev_to_node(&GET_DEV(accel_dev)));
	if (!irqs)
		return -ENOMEM;

	accel_dev->accel_pci_dev.msix_entries.num_entries = msix_num_entries;
	accel_dev->accel_pci_dev.msix_entries.irqs = irqs;
	return 0;
}

static void adf_isr_free_msix_vectors_data(struct adf_accel_dev *accel_dev)
{
	kfree(accel_dev->accel_pci_dev.msix_entries.irqs);
	accel_dev->accel_pci_dev.msix_entries.irqs = NULL;
}

static int adf_setup_bh(struct adf_accel_dev *accel_dev)
{
	struct adf_etr_data *priv_data = accel_dev->transport;
	struct adf_hw_device_data *hw_data = accel_dev->hw_device;
	int i;

	for (i = 0; i < hw_data->num_banks; i++)
		tasklet_init(&priv_data->banks[i].resp_handler,
			     adf_response_handler,
			     (unsigned long)&priv_data->banks[i]);
	return 0;
}

static void adf_cleanup_bh(struct adf_accel_dev *accel_dev)
{
	struct adf_etr_data *priv_data = accel_dev->transport;
	struct adf_hw_device_data *hw_data = accel_dev->hw_device;
	int i;

	for (i = 0; i < hw_data->num_banks; i++) {
		tasklet_disable(&priv_data->banks[i].resp_handler);
		tasklet_kill(&priv_data->banks[i].resp_handler);
	}
}

/**
 * adf_isr_resource_free() - Free IRQ for acceleration device
 * @accel_dev:  Pointer to acceleration device.
 *
 * Function frees interrupts for acceleration device.
 */
void adf_isr_resource_free(struct adf_accel_dev *accel_dev)
{
	adf_free_irqs(accel_dev);
	adf_cleanup_bh(accel_dev);
	adf_disable_msix(&accel_dev->accel_pci_dev);
	adf_isr_free_msix_vectors_data(accel_dev);
}
EXPORT_SYMBOL_GPL(adf_isr_resource_free);

/**
 * adf_isr_resource_alloc() - Allocate IRQ for acceleration device
 * @accel_dev:  Pointer to acceleration device.
 *
 * Function allocates interrupts for acceleration device.
 *
 * Return: 0 on success, error code otherwise.
 */
int adf_isr_resource_alloc(struct adf_accel_dev *accel_dev)
{
	int ret;

	ret = adf_isr_alloc_msix_vectors_data(accel_dev);
	if (ret)
		goto err_out;

	ret = adf_enable_msix(accel_dev);
	if (ret)
		goto err_free_msix_table;

	ret = adf_setup_bh(accel_dev);
	if (ret)
		goto err_disable_msix;

	ret = adf_request_irqs(accel_dev);
	if (ret)
		goto err_cleanup_bh;

	return 0;

err_cleanup_bh:
	adf_cleanup_bh(accel_dev);

err_disable_msix:
	adf_disable_msix(&accel_dev->accel_pci_dev);

err_free_msix_table:
	adf_isr_free_msix_vectors_data(accel_dev);

err_out:
	return ret;
}
EXPORT_SYMBOL_GPL(adf_isr_resource_alloc);

/**
 * adf_init_misc_wq() - Init misc workqueue
 *
 * Function init workqueue 'qat_misc_wq' for general purpose.
 *
 * Return: 0 on success, error code otherwise.
 */
int __init adf_init_misc_wq(void)
{
	adf_misc_wq = alloc_workqueue("qat_misc_wq", WQ_MEM_RECLAIM, 0);

	return !adf_misc_wq ? -ENOMEM : 0;
}

void adf_exit_misc_wq(void)
{
	if (adf_misc_wq)
		destroy_workqueue(adf_misc_wq);

	adf_misc_wq = NULL;
}

bool adf_misc_wq_queue_work(struct work_struct *work)
{
	return queue_work(adf_misc_wq, work);
}