// 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 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 = 1;

	/* If SR-IOV is disabled, add entries for each bank */
	if (!accel_dev->pf.vf_info) {
		int i;

		msix_num_entries += hw_data->num_banks;
		for (i = 0; i < msix_num_entries; i++)
			pci_dev_info->msix_entries.entries[i].entry = i;
	} else {
		pci_dev_info->msix_entries.entries[0].entry =
			hw_data->num_banks;
	}

	if (pci_enable_msix_exact(pci_dev_info->pci_dev,
				  pci_dev_info->msix_entries.entries,
				  msix_num_entries)) {
		dev_err(&GET_DEV(accel_dev), "Failed to enable MSI-X IRQ(s)\n");
		return -EFAULT;
	}
	return 0;
}

static void adf_disable_msix(struct adf_accel_pci *pci_dev_info)
{
	pci_disable_msix(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;

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

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) {
		struct adf_hw_device_data *hw_data = accel_dev->hw_device;
		struct adf_bar *pmisc =
			&GET_BARS(accel_dev)[hw_data->get_misc_bar_id(hw_data)];
		void __iomem *pmisc_bar_addr = pmisc->virt_addr;
		unsigned long vf_mask;

		/* Get the interrupt sources triggered by VFs */
		vf_mask = ((ADF_CSR_RD(pmisc_bar_addr, ADF_ERRSOU5) &
			    0x0000FFFF) << 16) |
			  ((ADF_CSR_RD(pmisc_bar_addr, ADF_ERRSOU3) &
			    0x01FFFE00) >> 9);

		if (vf_mask) {
			struct adf_accel_vf_info *vf_info;
			bool irq_handled = false;
			int i;

			/* Disable VF2PF interrupts for VFs with pending ints */
			adf_disable_vf2pf_interrupts(accel_dev, vf_mask);

			/*
			 * Schedule tasklets to handle VF2PF interrupt BHs
			 * 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 + 1);
					continue;
				}

				/* Tasklet will re-enable ints from this VF */
				tasklet_hi_schedule(&vf_info->vf2pf_bh_tasklet);
				irq_handled = true;
			}

			if (irq_handled)
				return IRQ_HANDLED;
		}
	}
#endif /* CONFIG_PCI_IOV */

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

	return IRQ_NONE;
}

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 msix_entry *msixe = pci_dev_info->msix_entries.entries;
	struct adf_etr_data *etr_data = accel_dev->transport;
	int ret, 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 = *(pci_dev_info->msix_entries.names + i);
			snprintf(name, ADF_MAX_MSIX_VECTOR_NAME,
				 "qat%d-bundle%d", accel_dev->accel_id, i);
			ret = request_irq(msixe[i].vector,
					  adf_msix_isr_bundle, 0, name, bank);
			if (ret) {
				dev_err(&GET_DEV(accel_dev),
					"failed to enable irq %d for %s\n",
					msixe[i].vector, name);
				return ret;
			}

			cpu = ((accel_dev->accel_id * hw_data->num_banks) +
			       i) % cpus;
			irq_set_affinity_hint(msixe[i].vector,
					      get_cpu_mask(cpu));
		}
	}

	/* Request msix irq for AE */
	name = *(pci_dev_info->msix_entries.names + i);
	snprintf(name, ADF_MAX_MSIX_VECTOR_NAME,
		 "qat%d-ae-cluster", accel_dev->accel_id);
	ret = request_irq(msixe[i].vector, adf_msix_isr_ae, 0, name, accel_dev);
	if (ret) {
		dev_err(&GET_DEV(accel_dev),
			"failed to enable irq %d, for %s\n",
			msixe[i].vector, name);
		return ret;
	}
	return ret;
}

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 msix_entry *msixe = pci_dev_info->msix_entries.entries;
	struct adf_etr_data *etr_data = accel_dev->transport;
	int i = 0;

	if (pci_dev_info->msix_entries.num_entries > 1) {
		for (i = 0; i < hw_data->num_banks; i++) {
			irq_set_affinity_hint(msixe[i].vector, NULL);
			free_irq(msixe[i].vector, &etr_data->banks[i]);
		}
	}
	irq_set_affinity_hint(msixe[i].vector, NULL);
	free_irq(msixe[i].vector, accel_dev);
}

static int adf_isr_alloc_msix_entry_table(struct adf_accel_dev *accel_dev)
{
	int i;
	char **names;
	struct msix_entry *entries;
	struct adf_hw_device_data *hw_data = accel_dev->hw_device;
	u32 msix_num_entries = 1;

	/* 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;

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

	names = kcalloc(msix_num_entries, sizeof(char *), GFP_KERNEL);
	if (!names) {
		kfree(entries);
		return -ENOMEM;
	}
	for (i = 0; i < msix_num_entries; i++) {
		*(names + i) = kzalloc(ADF_MAX_MSIX_VECTOR_NAME, GFP_KERNEL);
		if (!(*(names + i)))
			goto err;
	}
	accel_dev->accel_pci_dev.msix_entries.num_entries = msix_num_entries;
	accel_dev->accel_pci_dev.msix_entries.entries = entries;
	accel_dev->accel_pci_dev.msix_entries.names = names;
	return 0;
err:
	for (i = 0; i < msix_num_entries; i++)
		kfree(*(names + i));
	kfree(entries);
	kfree(names);
	return -ENOMEM;
}

static void adf_isr_free_msix_entry_table(struct adf_accel_dev *accel_dev)
{
	char **names = accel_dev->accel_pci_dev.msix_entries.names;
	int i;

	kfree(accel_dev->accel_pci_dev.msix_entries.entries);
	for (i = 0; i < accel_dev->accel_pci_dev.msix_entries.num_entries; i++)
		kfree(*(names + i));
	kfree(names);
}

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_entry_table(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_entry_table(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_entry_table(accel_dev);

err_out:
	return ret;
}
EXPORT_SYMBOL_GPL(adf_isr_resource_alloc);