// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2018 ARM Limited, All Rights Reserved.
* Author: Marc Zyngier <[email protected]>
*/
#define pr_fmt(fmt) "GICv3: " fmt
#include <linux/iommu.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/kernel.h>
#include <linux/msi.h>
#include <linux/of_address.h>
#include <linux/of_pci.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/irqchip/arm-gic-v3.h>
#include "irq-msi-lib.h"
struct mbi_range {
u32 spi_start;
u32 nr_spis;
unsigned long *bm;
};
static DEFINE_MUTEX(mbi_lock);
static phys_addr_t mbi_phys_base;
static struct mbi_range *mbi_ranges;
static unsigned int mbi_range_nr;
static struct irq_chip mbi_irq_chip = {
.name = "MBI",
.irq_mask = irq_chip_mask_parent,
.irq_unmask = irq_chip_unmask_parent,
.irq_eoi = irq_chip_eoi_parent,
.irq_set_type = irq_chip_set_type_parent,
.irq_set_affinity = irq_chip_set_affinity_parent,
};
static int mbi_irq_gic_domain_alloc(struct irq_domain *domain,
unsigned int virq,
irq_hw_number_t hwirq)
{
struct irq_fwspec fwspec;
struct irq_data *d;
int err;
/*
* Using ACPI? There is no MBI support in the spec, you
* shouldn't even be here.
*/
if (!is_of_node(domain->parent->fwnode))
return -EINVAL;
/*
* Let's default to edge. This is consistent with traditional
* MSIs, and systems requiring level signaling will just
* enforce the trigger on their own.
*/
fwspec.fwnode = domain->parent->fwnode;
fwspec.param_count = 3;
fwspec.param[0] = 0;
fwspec.param[1] = hwirq - 32;
fwspec.param[2] = IRQ_TYPE_EDGE_RISING;
err = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec);
if (err)
return err;
d = irq_domain_get_irq_data(domain->parent, virq);
return d->chip->irq_set_type(d, IRQ_TYPE_EDGE_RISING);
}
static void mbi_free_msi(struct mbi_range *mbi, unsigned int hwirq,
int nr_irqs)
{
mutex_lock(&mbi_lock);
bitmap_release_region(mbi->bm, hwirq - mbi->spi_start,
get_count_order(nr_irqs));
mutex_unlock(&mbi_lock);
}
static int mbi_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
unsigned int nr_irqs, void *args)
{
msi_alloc_info_t *info = args;
struct mbi_range *mbi = NULL;
int hwirq, offset, i, err = 0;
mutex_lock(&mbi_lock);
for (i = 0; i < mbi_range_nr; i++) {
offset = bitmap_find_free_region(mbi_ranges[i].bm,
mbi_ranges[i].nr_spis,
get_count_order(nr_irqs));
if (offset >= 0) {
mbi = &mbi_ranges[i];
break;
}
}
mutex_unlock(&mbi_lock);
if (!mbi)
return -ENOSPC;
hwirq = mbi->spi_start + offset;
err = iommu_dma_prepare_msi(info->desc,
mbi_phys_base + GICD_SETSPI_NSR);
if (err)
return err;
for (i = 0; i < nr_irqs; i++) {
err = mbi_irq_gic_domain_alloc(domain, virq + i, hwirq + i);
if (err)
goto fail;
irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
&mbi_irq_chip, mbi);
}
return 0;
fail:
irq_domain_free_irqs_parent(domain, virq, nr_irqs);
mbi_free_msi(mbi, hwirq, nr_irqs);
return err;
}
static void mbi_irq_domain_free(struct irq_domain *domain,
unsigned int virq, unsigned int nr_irqs)
{
struct irq_data *d = irq_domain_get_irq_data(domain, virq);
struct mbi_range *mbi = irq_data_get_irq_chip_data(d);
mbi_free_msi(mbi, d->hwirq, nr_irqs);
irq_domain_free_irqs_parent(domain, virq, nr_irqs);
}
static const struct irq_domain_ops mbi_domain_ops = {
.select = msi_lib_irq_domain_select,
.alloc = mbi_irq_domain_alloc,
.free = mbi_irq_domain_free,
};
static void mbi_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
{
msg[0].address_hi = upper_32_bits(mbi_phys_base + GICD_SETSPI_NSR);
msg[0].address_lo = lower_32_bits(mbi_phys_base + GICD_SETSPI_NSR);
msg[0].data = data->parent_data->hwirq;
iommu_dma_compose_msi_msg(irq_data_get_msi_desc(data), msg);
}
static void mbi_compose_mbi_msg(struct irq_data *data, struct msi_msg *msg)
{
mbi_compose_msi_msg(data, msg);
msg[1].address_hi = upper_32_bits(mbi_phys_base + GICD_CLRSPI_NSR);
msg[1].address_lo = lower_32_bits(mbi_phys_base + GICD_CLRSPI_NSR);
msg[1].data = data->parent_data->hwirq;
iommu_dma_compose_msi_msg(irq_data_get_msi_desc(data), &msg[1]);
}
static bool mbi_init_dev_msi_info(struct device *dev, struct irq_domain *domain,
struct irq_domain *real_parent, struct msi_domain_info *info)
{
if (!msi_lib_init_dev_msi_info(dev, domain, real_parent, info))
return false;
switch (info->bus_token) {
case DOMAIN_BUS_PCI_DEVICE_MSI:
case DOMAIN_BUS_PCI_DEVICE_MSIX:
info->chip->irq_compose_msi_msg = mbi_compose_msi_msg;
return true;
case DOMAIN_BUS_DEVICE_MSI:
info->chip->irq_compose_msi_msg = mbi_compose_mbi_msg;
info->chip->irq_set_type = irq_chip_set_type_parent;
info->chip->flags |= IRQCHIP_SUPPORTS_LEVEL_MSI;
info->flags |= MSI_FLAG_LEVEL_CAPABLE;
return true;
default:
WARN_ON_ONCE(1);
return false;
}
}
#define MBI_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS | \
MSI_FLAG_USE_DEF_CHIP_OPS | \
MSI_FLAG_PCI_MSI_MASK_PARENT)
#define MBI_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK | \
MSI_FLAG_PCI_MSIX | \
MSI_FLAG_MULTI_PCI_MSI)
static const struct msi_parent_ops gic_v3_mbi_msi_parent_ops = {
.supported_flags = MBI_MSI_FLAGS_SUPPORTED,
.required_flags = MBI_MSI_FLAGS_REQUIRED,
.bus_select_token = DOMAIN_BUS_NEXUS,
.bus_select_mask = MATCH_PCI_MSI | MATCH_PLATFORM_MSI,
.prefix = "MBI-",
.init_dev_msi_info = mbi_init_dev_msi_info,
};
static int mbi_allocate_domain(struct irq_domain *parent)
{
struct irq_domain *nexus_domain;
nexus_domain = irq_domain_create_hierarchy(parent, 0, 0, parent->fwnode,
&mbi_domain_ops, NULL);
if (!nexus_domain)
return -ENOMEM;
irq_domain_update_bus_token(nexus_domain, DOMAIN_BUS_NEXUS);
nexus_domain->flags |= IRQ_DOMAIN_FLAG_MSI_PARENT;
nexus_domain->msi_parent_ops = &gic_v3_mbi_msi_parent_ops;
return 0;
}
int __init mbi_init(struct fwnode_handle *fwnode, struct irq_domain *parent)
{
struct device_node *np;
const __be32 *reg;
int ret, n;
np = to_of_node(fwnode);
if (!of_property_read_bool(np, "msi-controller"))
return 0;
n = of_property_count_elems_of_size(np, "mbi-ranges", sizeof(u32));
if (n <= 0 || n % 2)
return -EINVAL;
mbi_range_nr = n / 2;
mbi_ranges = kcalloc(mbi_range_nr, sizeof(*mbi_ranges), GFP_KERNEL);
if (!mbi_ranges)
return -ENOMEM;
for (n = 0; n < mbi_range_nr; n++) {
ret = of_property_read_u32_index(np, "mbi-ranges", n * 2,
&mbi_ranges[n].spi_start);
if (ret)
goto err_free_mbi;
ret = of_property_read_u32_index(np, "mbi-ranges", n * 2 + 1,
&mbi_ranges[n].nr_spis);
if (ret)
goto err_free_mbi;
mbi_ranges[n].bm = bitmap_zalloc(mbi_ranges[n].nr_spis, GFP_KERNEL);
if (!mbi_ranges[n].bm) {
ret = -ENOMEM;
goto err_free_mbi;
}
pr_info("MBI range [%d:%d]\n", mbi_ranges[n].spi_start,
mbi_ranges[n].spi_start + mbi_ranges[n].nr_spis - 1);
}
reg = of_get_property(np, "mbi-alias", NULL);
if (reg) {
mbi_phys_base = of_translate_address(np, reg);
if (mbi_phys_base == (phys_addr_t)OF_BAD_ADDR) {
ret = -ENXIO;
goto err_free_mbi;
}
} else {
struct resource res;
if (of_address_to_resource(np, 0, &res)) {
ret = -ENXIO;
goto err_free_mbi;
}
mbi_phys_base = res.start;
}
pr_info("Using MBI frame %pa\n", &mbi_phys_base);
ret = mbi_allocate_domain(parent);
if (ret)
goto err_free_mbi;
return 0;
err_free_mbi:
if (mbi_ranges) {
for (n = 0; n < mbi_range_nr; n++)
bitmap_free(mbi_ranges[n].bm);
kfree(mbi_ranges);
}
return ret;
}
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