path: root/drivers/pci/controller/dwc/pcie-designware-host.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Synopsys DesignWare PCIe host controller driver
 *
 * Copyright (C) 2013 Samsung Electronics Co., Ltd.
 *		https://www.samsung.com
 *
 * Author: Jingoo Han <jg1.han@samsung.com>
 */

#include <linux/iopoll.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/irqdomain.h>
#include <linux/msi.h>
#include <linux/of_address.h>
#include <linux/of_pci.h>
#include <linux/pci_regs.h>
#include <linux/platform_device.h>

#include "../../pci.h"
#include "pcie-designware.h"

static struct pci_ops dw_pcie_ops;
static struct pci_ops dw_child_pcie_ops;

static void dw_msi_ack_irq(struct irq_data *d)
{
	irq_chip_ack_parent(d);
}

static void dw_msi_mask_irq(struct irq_data *d)
{
	pci_msi_mask_irq(d);
	irq_chip_mask_parent(d);
}

static void dw_msi_unmask_irq(struct irq_data *d)
{
	pci_msi_unmask_irq(d);
	irq_chip_unmask_parent(d);
}

static struct irq_chip dw_pcie_msi_irq_chip = {
	.name = "PCI-MSI",
	.irq_ack = dw_msi_ack_irq,
	.irq_mask = dw_msi_mask_irq,
	.irq_unmask = dw_msi_unmask_irq,
};

static struct msi_domain_info dw_pcie_msi_domain_info = {
	.flags	= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
		  MSI_FLAG_NO_AFFINITY | MSI_FLAG_PCI_MSIX |
		  MSI_FLAG_MULTI_PCI_MSI,
	.chip	= &dw_pcie_msi_irq_chip,
};

/* MSI int handler */
irqreturn_t dw_handle_msi_irq(struct dw_pcie_rp *pp)
{
	int i, pos;
	unsigned long val;
	u32 status, num_ctrls;
	irqreturn_t ret = IRQ_NONE;
	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);

	num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL;

	for (i = 0; i < num_ctrls; i++) {
		status = dw_pcie_readl_dbi(pci, PCIE_MSI_INTR0_STATUS +
					   (i * MSI_REG_CTRL_BLOCK_SIZE));
		if (!status)
			continue;

		ret = IRQ_HANDLED;
		val = status;
		pos = 0;
		while ((pos = find_next_bit(&val, MAX_MSI_IRQS_PER_CTRL,
					    pos)) != MAX_MSI_IRQS_PER_CTRL) {
			generic_handle_domain_irq(pp->irq_domain,
						  (i * MAX_MSI_IRQS_PER_CTRL) +
						  pos);
			pos++;
		}
	}

	return ret;
}

/* Chained MSI interrupt service routine */
static void dw_chained_msi_isr(struct irq_desc *desc)
{
	struct irq_chip *chip = irq_desc_get_chip(desc);
	struct dw_pcie_rp *pp;

	chained_irq_enter(chip, desc);

	pp = irq_desc_get_handler_data(desc);
	dw_handle_msi_irq(pp);

	chained_irq_exit(chip, desc);
}

static void dw_pci_setup_msi_msg(struct irq_data *d, struct msi_msg *msg)
{
	struct dw_pcie_rp *pp = irq_data_get_irq_chip_data(d);
	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
	u64 msi_target;

	msi_target = (u64)pp->msi_data;

	msg->address_lo = lower_32_bits(msi_target);
	msg->address_hi = upper_32_bits(msi_target);

	msg->data = d->hwirq;

	dev_dbg(pci->dev, "msi#%d address_hi %#x address_lo %#x\n",
		(int)d->hwirq, msg->address_hi, msg->address_lo);
}

static void dw_pci_bottom_mask(struct irq_data *d)
{
	struct dw_pcie_rp *pp = irq_data_get_irq_chip_data(d);
	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
	unsigned int res, bit, ctrl;
	unsigned long flags;

	raw_spin_lock_irqsave(&pp->lock, flags);

	ctrl = d->hwirq / MAX_MSI_IRQS_PER_CTRL;
	res = ctrl * MSI_REG_CTRL_BLOCK_SIZE;
	bit = d->hwirq % MAX_MSI_IRQS_PER_CTRL;

	pp->irq_mask[ctrl] |= BIT(bit);
	dw_pcie_writel_dbi(pci, PCIE_MSI_INTR0_MASK + res, pp->irq_mask[ctrl]);

	raw_spin_unlock_irqrestore(&pp->lock, flags);
}

static void dw_pci_bottom_unmask(struct irq_data *d)
{
	struct dw_pcie_rp *pp = irq_data_get_irq_chip_data(d);
	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
	unsigned int res, bit, ctrl;
	unsigned long flags;

	raw_spin_lock_irqsave(&pp->lock, flags);

	ctrl = d->hwirq / MAX_MSI_IRQS_PER_CTRL;
	res = ctrl * MSI_REG_CTRL_BLOCK_SIZE;
	bit = d->hwirq % MAX_MSI_IRQS_PER_CTRL;

	pp->irq_mask[ctrl] &= ~BIT(bit);
	dw_pcie_writel_dbi(pci, PCIE_MSI_INTR0_MASK + res, pp->irq_mask[ctrl]);

	raw_spin_unlock_irqrestore(&pp->lock, flags);
}

static void dw_pci_bottom_ack(struct irq_data *d)
{
	struct dw_pcie_rp *pp  = irq_data_get_irq_chip_data(d);
	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
	unsigned int res, bit, ctrl;

	ctrl = d->hwirq / MAX_MSI_IRQS_PER_CTRL;
	res = ctrl * MSI_REG_CTRL_BLOCK_SIZE;
	bit = d->hwirq % MAX_MSI_IRQS_PER_CTRL;

	dw_pcie_writel_dbi(pci, PCIE_MSI_INTR0_STATUS + res, BIT(bit));
}

static struct irq_chip dw_pci_msi_bottom_irq_chip = {
	.name = "DWPCI-MSI",
	.irq_ack = dw_pci_bottom_ack,
	.irq_compose_msi_msg = dw_pci_setup_msi_msg,
	.irq_mask = dw_pci_bottom_mask,
	.irq_unmask = dw_pci_bottom_unmask,
};

static int dw_pcie_irq_domain_alloc(struct irq_domain *domain,
				    unsigned int virq, unsigned int nr_irqs,
				    void *args)
{
	struct dw_pcie_rp *pp = domain->host_data;