linux-imx

/*

 * Annapurna Labs MSIX support services

 *

 * Copyright (C) 2016, Amazon.com, Inc. or its affiliates. All Rights Reserved.

 *

 * Antoine Tenart <antoine.tenart@free-electrons.com>

 *

 * This file is licensed under the terms of the GNU General Public

 * License version 2. This program is licensed "as is" without any

 * warranty of any kind, whether express or implied.

 */

​

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

​

#include <linux/irqchip.h>

#include <linux/irqchip/arm-gic.h>

#include <linux/msi.h>

#include <linux/of.h>

#include <linux/of_address.h>

#include <linux/of_irq.h>

#include <linux/of_pci.h>

#include <linux/pci.h>

#include <linux/slab.h>

​

#include <asm/irq.h>

#include <asm/msi.h>

​

/* MSIX message address format: local GIC target */

#define ALPINE_MSIX_SPI_TARGET_CLUSTER0     BIT(16)

​

struct alpine_msix_data {

    spinlock_t msi_map_lock;

    phys_addr_t addr;

    u32 spi_first;      /* The SGI number that MSIs start */

    u32 num_spis;       /* The number of SGIs for MSIs */

    unsigned long *msi_map;

};

​

static void alpine_msix_mask_msi_irq(struct irq_data *d)

{

    pci_msi_mask_irq(d);

    irq_chip_mask_parent(d);

}

​

static void alpine_msix_unmask_msi_irq(struct irq_data *d)

{

    pci_msi_unmask_irq(d);

    irq_chip_unmask_parent(d);

}

​

static struct irq_chip alpine_msix_irq_chip = {

    .name           = "MSIx",

    .irq_mask       = alpine_msix_mask_msi_irq,

    .irq_unmask     = alpine_msix_unmask_msi_irq,

    .irq_eoi        = irq_chip_eoi_parent,

    .irq_set_affinity   = irq_chip_set_affinity_parent,

};

​

static int alpine_msix_allocate_sgi(struct alpine_msix_data *priv, int num_req)

{

    int first;

​

    spin_lock(&priv->msi_map_lock);

​

    first = bitmap_find_next_zero_area(priv->msi_map, priv->num_spis, 0,

                       num_req, 0);

    if (first >= priv->num_spis) {

        spin_unlock(&priv->msi_map_lock);

        return -ENOSPC;

    }

​

    bitmap_set(priv->msi_map, first, num_req);

​

    spin_unlock(&priv->msi_map_lock);

​

    return priv->spi_first + first;

}

​

static void alpine_msix_free_sgi(struct alpine_msix_data *priv, unsigned sgi,

                 int num_req)

{

    int first = sgi - priv->spi_first;

​

    spin_lock(&priv->msi_map_lock);

​

    bitmap_clear(priv->msi_map, first, num_req);

​

    spin_unlock(&priv->msi_map_lock);

}

​

static void alpine_msix_compose_msi_msg(struct irq_data *data,

                    struct msi_msg *msg)