// SPDX-License-Identifier: GPL-2.0-only
/*
* ARM GIC v2m MSI(-X) support
* Support for Message Signaled Interrupts for systems that
* implement ARM Generic Interrupt Controller: GICv2m.
*
* Copyright (C) 2014 Advanced Micro Devices, Inc.
* Authors: Suravee Suthikulpanit <[email protected]>
* Harish Kasiviswanathan <[email protected]>
* Brandon Anderson <[email protected]>
*/
#define pr_fmt(fmt) "GICv2m: " fmt
#include <linux/acpi.h>
#include <linux/iommu.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/kernel.h>
#include <linux/pci.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.h>
#include <linux/irqchip/arm-gic-common.h>
#include "irq-msi-lib.h"
/*
* MSI_TYPER:
* [31:26] Reserved
* [25:16] lowest SPI assigned to MSI
* [15:10] Reserved
* [9:0] Numer of SPIs assigned to MSI
*/
#define V2M_MSI_TYPER 0x008
#define V2M_MSI_TYPER_BASE_SHIFT 16
#define V2M_MSI_TYPER_BASE_MASK 0x3FF
#define V2M_MSI_TYPER_NUM_MASK 0x3FF
#define V2M_MSI_SETSPI_NS 0x040
#define V2M_MIN_SPI 32
#define V2M_MAX_SPI 1019
#define V2M_MSI_IIDR 0xFCC
#define V2M_MSI_TYPER_BASE_SPI(x) \
(((x) >> V2M_MSI_TYPER_BASE_SHIFT) & V2M_MSI_TYPER_BASE_MASK)
#define V2M_MSI_TYPER_NUM_SPI(x) ((x) & V2M_MSI_TYPER_NUM_MASK)
/* APM X-Gene with GICv2m MSI_IIDR register value */
#define XGENE_GICV2M_MSI_IIDR 0x06000170
/* Broadcom NS2 GICv2m MSI_IIDR register value */
#define BCM_NS2_GICV2M_MSI_IIDR 0x0000013f
/* List of flags for specific v2m implementation */
#define GICV2M_NEEDS_SPI_OFFSET 0x00000001
#define GICV2M_GRAVITON_ADDRESS_ONLY 0x00000002
static LIST_HEAD(v2m_nodes);
static DEFINE_SPINLOCK(v2m_lock);
struct v2m_data {
struct list_head entry;
struct fwnode_handle *fwnode;
struct resource res; /* GICv2m resource */
void __iomem *base; /* GICv2m virt address */
u32 spi_start; /* The SPI number that MSIs start */
u32 nr_spis; /* The number of SPIs for MSIs */
u32 spi_offset; /* offset to be subtracted from SPI number */
unsigned long *bm; /* MSI vector bitmap */
u32 flags; /* v2m flags for specific implementation */
};
static phys_addr_t gicv2m_get_msi_addr(struct v2m_data *v2m, int hwirq)
{
if (v2m->flags & GICV2M_GRAVITON_ADDRESS_ONLY)
return v2m->res.start | ((hwirq - 32) << 3);
else
return v2m->res.start + V2M_MSI_SETSPI_NS;
}
static void gicv2m_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
{
struct v2m_data *v2m = irq_data_get_irq_chip_data(data);
phys_addr_t addr = gicv2m_get_msi_addr(v2m, data->hwirq);
msg->address_hi = upper_32_bits(addr);
msg->address_lo = lower_32_bits(addr);
if (v2m->flags & GICV2M_GRAVITON_ADDRESS_ONLY)
msg->data = 0;
else
msg->data = data->hwirq;
if (v2m->flags & GICV2M_NEEDS_SPI_OFFSET)
msg->data -= v2m->spi_offset;
iommu_dma_compose_msi_msg(irq_data_get_msi_desc(data), msg);
}
static struct irq_chip gicv2m_irq_chip = {
.name = "GICv2m",
.irq_mask = irq_chip_mask_parent,
.irq_unmask = irq_chip_unmask_parent,
.irq_eoi = irq_chip_eoi_parent,
.irq_set_affinity = irq_chip_set_affinity_parent,
.irq_compose_msi_msg = gicv2m_compose_msi_msg,
};
static int gicv2m_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;
if (is_of_node(domain->parent->fwnode)) {
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;
} else if (is_fwnode_irqchip(domain->parent->fwnode)) {
fwspec.fwnode = domain->parent->fwnode;
fwspec.param_count = 2;
fwspec.param[0] = hwirq;
fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
} else {
return -EINVAL;
}
err = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec);
if (err)
return err;
/* Configure the interrupt line to be edge */
d = irq_domain_get_irq_data(domain->parent, virq);
d->chip->irq_set_type(d, IRQ_TYPE_EDGE_RISING);
return 0;
}
static void gicv2m_unalloc_msi(struct v2m_data *v2m, unsigned int hwirq,
int nr_irqs)
{
spin_lock(&v2m_lock);
bitmap_release_region(v2m->bm, hwirq - v2m->spi_start,
get_count_order(nr_irqs));
spin_unlock(&v2m_lock);
}
static int gicv2m_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
unsigned int nr_irqs, void *args)
{
msi_alloc_info_t *info = args;
struct v2m_data *v2m = NULL, *tmp;
int hwirq, offset, i, err = 0;
spin_lock(&v2m_lock);
list_for_each_entry(tmp, &v2m_nodes, entry) {
offset = bitmap_find_free_region(tmp->bm, tmp->nr_spis,
get_count_order(nr_irqs));
if (offset >= 0) {
v2m = tmp;
break;
}
}
spin_unlock(&v2m_lock);
if (!v2m)
return -ENOSPC;
hwirq = v2m->spi_start + offset;
err = iommu_dma_prepare_msi(info->desc,
gicv2m_get_msi_addr(v2m, hwirq));
if (err)
return err;
for (i = 0; i < nr_irqs; i++) {
err = gicv2m_irq_gic_domain_alloc(domain, virq + i, hwirq + i);
if (err)
goto fail;
irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
&gicv2m_irq_chip, v2m);
}
return 0;
fail:
irq_domain_free_irqs_parent(domain, virq, nr_irqs);
gicv2m_unalloc_msi(v2m, hwirq, nr_irqs);
return err;
}
static void gicv2m_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 v2m_data *v2m = irq_data_get_irq_chip_data(d);
gicv2m_unalloc_msi(v2m, d->hwirq, nr_irqs);
irq_domain_free_irqs_parent(domain, virq, nr_irqs);
}
static const struct irq_domain_ops gicv2m_domain_ops = {
.select = msi_lib_irq_domain_select,
.alloc = gicv2m_irq_domain_alloc,
.free = gicv2m_irq_domain_free,
};
static bool is_msi_spi_valid(u32 base, u32 num)
{
if (base < V2M_MIN_SPI) {
pr_err("Invalid MSI base SPI (base:%u)\n", base);
return false;
}
if ((num == 0) || (base + num > V2M_MAX_SPI)) {
pr_err("Number of SPIs (%u) exceed maximum (%u)\n",
num, V2M_MAX_SPI - V2M_MIN_SPI + 1);
return false;
}
return true;
}
static void __init gicv2m_teardown(void)
{
struct v2m_data *v2m, *tmp;
list_for_each_entry_safe(v2m, tmp, &v2m_nodes, entry) {
list_del(&v2m->entry);
bitmap_free(v2m->bm);
iounmap(v2m->base);
of_node_put(to_of_node(v2m->fwnode));
if (is_fwnode_irqchip(v2m->fwnode))
irq_domain_free_fwnode(v2m->fwnode);
kfree(v2m);
}
}
#define GICV2M_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS | \
MSI_FLAG_USE_DEF_CHIP_OPS | \
MSI_FLAG_PCI_MSI_MASK_PARENT)
#define GICV2M_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK | \
MSI_FLAG_PCI_MSIX | \
MSI_FLAG_MULTI_PCI_MSI)
static struct msi_parent_ops gicv2m_msi_parent_ops = {
.supported_flags = GICV2M_MSI_FLAGS_SUPPORTED,
.required_flags = GICV2M_MSI_FLAGS_REQUIRED,
.bus_select_token = DOMAIN_BUS_NEXUS,
.bus_select_mask = MATCH_PCI_MSI | MATCH_PLATFORM_MSI,
.prefix = "GICv2m-",
.init_dev_msi_info = msi_lib_init_dev_msi_info,
};
static __init int gicv2m_allocate_domains(struct irq_domain *parent)
{
struct irq_domain *inner_domain;
struct v2m_data *v2m;
v2m = list_first_entry_or_null(&v2m_nodes, struct v2m_data, entry);
if (!v2m)
return 0;
inner_domain = irq_domain_create_hierarchy(parent, 0, 0, v2m->fwnode,
&gicv2m_domain_ops, v2m);
if (!inner_domain) {
pr_err("Failed to create GICv2m domain\n");
return -ENOMEM;
}
irq_domain_update_bus_token(inner_domain, DOMAIN_BUS_NEXUS);
inner_domain->flags |= IRQ_DOMAIN_FLAG_MSI_PARENT;
inner_domain->msi_parent_ops = &gicv2m_msi_parent_ops;
return 0;
}
static int __init gicv2m_init_one(struct fwnode_handle *fwnode,
u32 spi_start, u32 nr_spis,
struct resource *res, u32 flags)
{
int ret;
struct v2m_data *v2m;
v2m = kzalloc(sizeof(struct v2m_data), GFP_KERNEL);
if (!v2m)
return -ENOMEM;
INIT_LIST_HEAD(&v2m->entry);
v2m->fwnode = fwnode;
v2m->flags = flags;
memcpy(&v2m->res, res, sizeof(struct resource));
v2m->base = ioremap(v2m->res.start, resource_size(&v2m->res));
if (!v2m->base) {
pr_err("Failed to map GICv2m resource\n");
ret = -ENOMEM;
goto err_free_v2m;
}
if (spi_start && nr_spis) {
v2m->spi_start = spi_start;
v2m->nr_spis = nr_spis;
} else {
u32 typer;
/* Graviton should always have explicit spi_start/nr_spis */
if (v2m->flags & GICV2M_GRAVITON_ADDRESS_ONLY) {
ret = -EINVAL;
goto err_iounmap;
}
typer = readl_relaxed(v2m->base + V2M_MSI_TYPER);
v2m->spi_start = V2M_MSI_TYPER_BASE_SPI(typer);
v2m->nr_spis = V2M_MSI_TYPER_NUM_SPI(typer);
}
if (!is_msi_spi_valid(v2m->spi_start, v2m->nr_spis)) {
ret = -EINVAL;
goto err_iounmap;
}
/*
* APM X-Gene GICv2m implementation has an erratum where
* the MSI data needs to be the offset from the spi_start
* in order to trigger the correct MSI interrupt. This is
* different from the standard GICv2m implementation where
* the MSI data is the absolute value within the range from
* spi_start to (spi_start + num_spis).
*
* Broadcom NS2 GICv2m implementation has an erratum where the MSI data
* is 'spi_number - 32'
*
* Reading that register fails on the Graviton implementation
*/
if (!(v2m->flags & GICV2M_GRAVITON_ADDRESS_ONLY)) {
switch (readl_relaxed(v2m->base + V2M_MSI_IIDR)) {
case XGENE_GICV2M_MSI_IIDR:
v2m->flags |= GICV2M_NEEDS_SPI_OFFSET;
v2m->spi_offset = v2m->spi_start;
break;
case BCM_NS2_GICV2M_MSI_IIDR:
v2m->flags |= GICV2M_NEEDS_SPI_OFFSET;
v2m->spi_offset = 32;
break;
}
}
v2m->bm = bitmap_zalloc(v2m->nr_spis, GFP_KERNEL);
if (!v2m->bm) {
ret = -ENOMEM;
goto err_iounmap;
}
list_add_tail(&v2m->entry, &v2m_nodes);
pr_info("range%pR, SPI[%d:%d]\n", res,
v2m->spi_start, (v2m->spi_start + v2m->nr_spis - 1));
return 0;
err_iounmap:
iounmap(v2m->base);
err_free_v2m:
kfree(v2m);
return ret;
}
static __initconst struct of_device_id gicv2m_device_id[] = {
{ .compatible = "arm,gic-v2m-frame", },
{},
};
static int __init gicv2m_of_init(struct fwnode_handle *parent_handle,
struct irq_domain *parent)
{
int ret = 0;
struct device_node *node = to_of_node(parent_handle);
struct device_node *child;
for (child = of_find_matching_node(node, gicv2m_device_id); child;
child = of_find_matching_node(child, gicv2m_device_id)) {
u32 spi_start = 0, nr_spis = 0;
struct resource res;
if (!of_property_read_bool(child, "msi-controller"))
continue;
ret = of_address_to_resource(child, 0, &res);
if (ret) {
pr_err("Failed to allocate v2m resource.\n");
break;
}
if (!of_property_read_u32(child, "arm,msi-base-spi",
&spi_start) &&
!of_property_read_u32(child, "arm,msi-num-spis", &nr_spis))
pr_info("DT overriding V2M MSI_TYPER (base:%u, num:%u)\n",
spi_start, nr_spis);
ret = gicv2m_init_one(&child->fwnode, spi_start, nr_spis,
&res, 0);
if (ret) {
of_node_put(child);
break;
}
}
if (!ret)
ret = gicv2m_allocate_domains(parent);
if (ret)
gicv2m_teardown();
return ret;
}
#ifdef CONFIG_ACPI
static int acpi_num_msi;
static __init struct fwnode_handle *gicv2m_get_fwnode(struct device *dev)
{
struct v2m_data *data;
if (WARN_ON(acpi_num_msi <= 0))
return NULL;
/* We only return the fwnode of the first MSI frame. */
data = list_first_entry_or_null(&v2m_nodes, struct v2m_data, entry);
if (!data)
return NULL;
return data->fwnode;
}
static __init bool acpi_check_amazon_graviton_quirks(void)
{
static struct acpi_table_madt *madt;
acpi_status status;
bool rc = false;
#define ACPI_AMZN_OEM_ID "AMAZON"
status = acpi_get_table(ACPI_SIG_MADT, 0,
(struct acpi_table_header **)&madt);
if (ACPI_FAILURE(status) || !madt)
return rc;
rc = !memcmp(madt->header.oem_id, ACPI_AMZN_OEM_ID, ACPI_OEM_ID_SIZE);
acpi_put_table((struct acpi_table_header *)madt);
return rc;
}
static int __init
acpi_parse_madt_msi(union acpi_subtable_headers *header,
const unsigned long end)
{
int ret;
struct resource res;
u32 spi_start = 0, nr_spis = 0;
struct acpi_madt_generic_msi_frame *m;
struct fwnode_handle *fwnode;
u32 flags = 0;
m = (struct acpi_madt_generic_msi_frame *)header;
if (BAD_MADT_ENTRY(m, end))
return -EINVAL;
res.start = m->base_address;
res.end = m->base_address + SZ_4K - 1;
res.flags = IORESOURCE_MEM;
if (acpi_check_amazon_graviton_quirks()) {
pr_info("applying Amazon Graviton quirk\n");
res.end = res.start + SZ_8K - 1;
flags |= GICV2M_GRAVITON_ADDRESS_ONLY;
gicv2m_msi_parent_ops.supported_flags &= ~MSI_FLAG_MULTI_PCI_MSI;
}
if (m->flags & ACPI_MADT_OVERRIDE_SPI_VALUES) {
spi_start = m->spi_base;
nr_spis = m->spi_count;
pr_info("ACPI overriding V2M MSI_TYPER (base:%u, num:%u)\n",
spi_start, nr_spis);
}
fwnode = irq_domain_alloc_fwnode(&res.start);
if (!fwnode) {
pr_err("Unable to allocate GICv2m domain token\n");
return -EINVAL;
}
ret = gicv2m_init_one(fwnode, spi_start, nr_spis, &res, flags);
if (ret)
irq_domain_free_fwnode(fwnode);
return ret;
}
static int __init gicv2m_acpi_init(struct irq_domain *parent)
{
int ret;
if (acpi_num_msi > 0)
return 0;
acpi_num_msi = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_MSI_FRAME,
acpi_parse_madt_msi, 0);
if (acpi_num_msi <= 0)
goto err_out;
ret = gicv2m_allocate_domains(parent);
if (ret)
goto err_out;
pci_msi_register_fwnode_provider(&gicv2m_get_fwnode);
return 0;
err_out:
gicv2m_teardown();
return -EINVAL;
}
#else /* CONFIG_ACPI */
static int __init gicv2m_acpi_init(struct irq_domain *parent)
{
return -EINVAL;
}
#endif /* CONFIG_ACPI */
int __init gicv2m_init(struct fwnode_handle *parent_handle,
struct irq_domain *parent)
{
if (is_of_node(parent_handle))
return gicv2m_of_init(parent_handle, parent);
return gicv2m_acpi_init(parent);
}
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