https://github.com/torvalds/linux
Tip revision: ba4f184e126b751d1bffad5897f263108befc780 authored by Linus Torvalds on 20 September 2020, 23:33:55 UTC
Linux 5.9-rc6
Linux 5.9-rc6
Tip revision: ba4f184
msi.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* Support of MSI, HPET and DMAR interrupts.
*
* Copyright (C) 1997, 1998, 1999, 2000, 2009 Ingo Molnar, Hajnalka Szabo
* Moved from arch/x86/kernel/apic/io_apic.c.
* Jiang Liu <jiang.liu@linux.intel.com>
* Convert to hierarchical irqdomain
*/
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/pci.h>
#include <linux/dmar.h>
#include <linux/hpet.h>
#include <linux/msi.h>
#include <asm/irqdomain.h>
#include <asm/msidef.h>
#include <asm/hpet.h>
#include <asm/hw_irq.h>
#include <asm/apic.h>
#include <asm/irq_remapping.h>
static struct irq_domain *msi_default_domain;
static void __irq_msi_compose_msg(struct irq_cfg *cfg, struct msi_msg *msg)
{
msg->address_hi = MSI_ADDR_BASE_HI;
if (x2apic_enabled())
msg->address_hi |= MSI_ADDR_EXT_DEST_ID(cfg->dest_apicid);
msg->address_lo =
MSI_ADDR_BASE_LO |
((apic->irq_dest_mode == 0) ?
MSI_ADDR_DEST_MODE_PHYSICAL :
MSI_ADDR_DEST_MODE_LOGICAL) |
MSI_ADDR_REDIRECTION_CPU |
MSI_ADDR_DEST_ID(cfg->dest_apicid);
msg->data =
MSI_DATA_TRIGGER_EDGE |
MSI_DATA_LEVEL_ASSERT |
MSI_DATA_DELIVERY_FIXED |
MSI_DATA_VECTOR(cfg->vector);
}
static void irq_msi_compose_msg(struct irq_data *data, struct msi_msg *msg)
{
__irq_msi_compose_msg(irqd_cfg(data), msg);
}
static void irq_msi_update_msg(struct irq_data *irqd, struct irq_cfg *cfg)
{
struct msi_msg msg[2] = { [1] = { }, };
__irq_msi_compose_msg(cfg, msg);
irq_data_get_irq_chip(irqd)->irq_write_msi_msg(irqd, msg);
}
static int
msi_set_affinity(struct irq_data *irqd, const struct cpumask *mask, bool force)
{
struct irq_cfg old_cfg, *cfg = irqd_cfg(irqd);
struct irq_data *parent = irqd->parent_data;
unsigned int cpu;
int ret;
/* Save the current configuration */
cpu = cpumask_first(irq_data_get_effective_affinity_mask(irqd));
old_cfg = *cfg;
/* Allocate a new target vector */
ret = parent->chip->irq_set_affinity(parent, mask, force);
if (ret < 0 || ret == IRQ_SET_MASK_OK_DONE)
return ret;
/*
* For non-maskable and non-remapped MSI interrupts the migration
* to a different destination CPU and a different vector has to be
* done careful to handle the possible stray interrupt which can be
* caused by the non-atomic update of the address/data pair.
*
* Direct update is possible when:
* - The MSI is maskable (remapped MSI does not use this code path)).
* The quirk bit is not set in this case.
* - The new vector is the same as the old vector
* - The old vector is MANAGED_IRQ_SHUTDOWN_VECTOR (interrupt starts up)
* - The new destination CPU is the same as the old destination CPU
*/
if (!irqd_msi_nomask_quirk(irqd) ||
cfg->vector == old_cfg.vector ||
old_cfg.vector == MANAGED_IRQ_SHUTDOWN_VECTOR ||
cfg->dest_apicid == old_cfg.dest_apicid) {
irq_msi_update_msg(irqd, cfg);
return ret;
}
/*
* Paranoia: Validate that the interrupt target is the local
* CPU.
*/
if (WARN_ON_ONCE(cpu != smp_processor_id())) {
irq_msi_update_msg(irqd, cfg);
return ret;
}
/*
* Redirect the interrupt to the new vector on the current CPU
* first. This might cause a spurious interrupt on this vector if
* the device raises an interrupt right between this update and the
* update to the final destination CPU.
*
* If the vector is in use then the installed device handler will
* denote it as spurious which is no harm as this is a rare event
* and interrupt handlers have to cope with spurious interrupts
* anyway. If the vector is unused, then it is marked so it won't
* trigger the 'No irq handler for vector' warning in
* common_interrupt().
*
* This requires to hold vector lock to prevent concurrent updates to
* the affected vector.
*/
lock_vector_lock();
/*
* Mark the new target vector on the local CPU if it is currently
* unused. Reuse the VECTOR_RETRIGGERED state which is also used in
* the CPU hotplug path for a similar purpose. This cannot be
* undone here as the current CPU has interrupts disabled and
* cannot handle the interrupt before the whole set_affinity()
* section is done. In the CPU unplug case, the current CPU is
* about to vanish and will not handle any interrupts anymore. The
* vector is cleaned up when the CPU comes online again.
*/
if (IS_ERR_OR_NULL(this_cpu_read(vector_irq[cfg->vector])))
this_cpu_write(vector_irq[cfg->vector], VECTOR_RETRIGGERED);
/* Redirect it to the new vector on the local CPU temporarily */
old_cfg.vector = cfg->vector;
irq_msi_update_msg(irqd, &old_cfg);
/* Now transition it to the target CPU */
irq_msi_update_msg(irqd, cfg);
/*
* All interrupts after this point are now targeted at the new
* vector/CPU.
*
* Drop vector lock before testing whether the temporary assignment
* to the local CPU was hit by an interrupt raised in the device,
* because the retrigger function acquires vector lock again.
*/
unlock_vector_lock();
/*
* Check whether the transition raced with a device interrupt and
* is pending in the local APICs IRR. It is safe to do this outside
* of vector lock as the irq_desc::lock of this interrupt is still
* held and interrupts are disabled: The check is not accessing the
* underlying vector store. It's just checking the local APIC's
* IRR.
*/
if (lapic_vector_set_in_irr(cfg->vector))
irq_data_get_irq_chip(irqd)->irq_retrigger(irqd);
return ret;
}
/*
* IRQ Chip for MSI PCI/PCI-X/PCI-Express Devices,
* which implement the MSI or MSI-X Capability Structure.
*/
static struct irq_chip pci_msi_controller = {
.name = "PCI-MSI",
.irq_unmask = pci_msi_unmask_irq,
.irq_mask = pci_msi_mask_irq,
.irq_ack = irq_chip_ack_parent,
.irq_retrigger = irq_chip_retrigger_hierarchy,
.irq_compose_msi_msg = irq_msi_compose_msg,
.irq_set_affinity = msi_set_affinity,
.flags = IRQCHIP_SKIP_SET_WAKE,
};
int native_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
{
struct irq_domain *domain;
struct irq_alloc_info info;
init_irq_alloc_info(&info, NULL);
info.type = X86_IRQ_ALLOC_TYPE_MSI;
info.msi_dev = dev;
domain = irq_remapping_get_irq_domain(&info);
if (domain == NULL)
domain = msi_default_domain;
if (domain == NULL)
return -ENOSYS;
return msi_domain_alloc_irqs(domain, &dev->dev, nvec);
}
void native_teardown_msi_irq(unsigned int irq)
{
irq_domain_free_irqs(irq, 1);
}
static irq_hw_number_t pci_msi_get_hwirq(struct msi_domain_info *info,
msi_alloc_info_t *arg)
{
return arg->msi_hwirq;
}
int pci_msi_prepare(struct irq_domain *domain, struct device *dev, int nvec,
msi_alloc_info_t *arg)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct msi_desc *desc = first_pci_msi_entry(pdev);
init_irq_alloc_info(arg, NULL);
arg->msi_dev = pdev;
if (desc->msi_attrib.is_msix) {
arg->type = X86_IRQ_ALLOC_TYPE_MSIX;
} else {
arg->type = X86_IRQ_ALLOC_TYPE_MSI;
arg->flags |= X86_IRQ_ALLOC_CONTIGUOUS_VECTORS;
}
return 0;
}
EXPORT_SYMBOL_GPL(pci_msi_prepare);
void pci_msi_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
{
arg->msi_hwirq = pci_msi_domain_calc_hwirq(arg->msi_dev, desc);
}
EXPORT_SYMBOL_GPL(pci_msi_set_desc);
static struct msi_domain_ops pci_msi_domain_ops = {
.get_hwirq = pci_msi_get_hwirq,
.msi_prepare = pci_msi_prepare,
.set_desc = pci_msi_set_desc,
};
static struct msi_domain_info pci_msi_domain_info = {
.flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
MSI_FLAG_PCI_MSIX,
.ops = &pci_msi_domain_ops,
.chip = &pci_msi_controller,
.handler = handle_edge_irq,
.handler_name = "edge",
};
void __init arch_init_msi_domain(struct irq_domain *parent)
{
struct fwnode_handle *fn;
if (disable_apic)
return;
fn = irq_domain_alloc_named_fwnode("PCI-MSI");
if (fn) {
msi_default_domain =
pci_msi_create_irq_domain(fn, &pci_msi_domain_info,
parent);
}
if (!msi_default_domain) {
irq_domain_free_fwnode(fn);
pr_warn("failed to initialize irqdomain for MSI/MSI-x.\n");
} else {
msi_default_domain->flags |= IRQ_DOMAIN_MSI_NOMASK_QUIRK;
}
}
#ifdef CONFIG_IRQ_REMAP
static struct irq_chip pci_msi_ir_controller = {
.name = "IR-PCI-MSI",
.irq_unmask = pci_msi_unmask_irq,
.irq_mask = pci_msi_mask_irq,
.irq_ack = irq_chip_ack_parent,
.irq_retrigger = irq_chip_retrigger_hierarchy,
.irq_set_vcpu_affinity = irq_chip_set_vcpu_affinity_parent,
.flags = IRQCHIP_SKIP_SET_WAKE,
};
static struct msi_domain_info pci_msi_ir_domain_info = {
.flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX,
.ops = &pci_msi_domain_ops,
.chip = &pci_msi_ir_controller,
.handler = handle_edge_irq,
.handler_name = "edge",
};
struct irq_domain *arch_create_remap_msi_irq_domain(struct irq_domain *parent,
const char *name, int id)
{
struct fwnode_handle *fn;
struct irq_domain *d;
fn = irq_domain_alloc_named_id_fwnode(name, id);
if (!fn)
return NULL;
d = pci_msi_create_irq_domain(fn, &pci_msi_ir_domain_info, parent);
if (!d)
irq_domain_free_fwnode(fn);
return d;
}
#endif
#ifdef CONFIG_DMAR_TABLE
static void dmar_msi_write_msg(struct irq_data *data, struct msi_msg *msg)
{
dmar_msi_write(data->irq, msg);
}
static struct irq_chip dmar_msi_controller = {
.name = "DMAR-MSI",
.irq_unmask = dmar_msi_unmask,
.irq_mask = dmar_msi_mask,
.irq_ack = irq_chip_ack_parent,
.irq_set_affinity = msi_domain_set_affinity,
.irq_retrigger = irq_chip_retrigger_hierarchy,
.irq_compose_msi_msg = irq_msi_compose_msg,
.irq_write_msi_msg = dmar_msi_write_msg,
.flags = IRQCHIP_SKIP_SET_WAKE,
};
static irq_hw_number_t dmar_msi_get_hwirq(struct msi_domain_info *info,
msi_alloc_info_t *arg)
{
return arg->dmar_id;
}
static int dmar_msi_init(struct irq_domain *domain,
struct msi_domain_info *info, unsigned int virq,
irq_hw_number_t hwirq, msi_alloc_info_t *arg)
{
irq_domain_set_info(domain, virq, arg->dmar_id, info->chip, NULL,
handle_edge_irq, arg->dmar_data, "edge");
return 0;
}
static struct msi_domain_ops dmar_msi_domain_ops = {
.get_hwirq = dmar_msi_get_hwirq,
.msi_init = dmar_msi_init,
};
static struct msi_domain_info dmar_msi_domain_info = {
.ops = &dmar_msi_domain_ops,
.chip = &dmar_msi_controller,
};
static struct irq_domain *dmar_get_irq_domain(void)
{
static struct irq_domain *dmar_domain;
static DEFINE_MUTEX(dmar_lock);
struct fwnode_handle *fn;
mutex_lock(&dmar_lock);
if (dmar_domain)
goto out;
fn = irq_domain_alloc_named_fwnode("DMAR-MSI");
if (fn) {
dmar_domain = msi_create_irq_domain(fn, &dmar_msi_domain_info,
x86_vector_domain);
if (!dmar_domain)
irq_domain_free_fwnode(fn);
}
out:
mutex_unlock(&dmar_lock);
return dmar_domain;
}
int dmar_alloc_hwirq(int id, int node, void *arg)
{
struct irq_domain *domain = dmar_get_irq_domain();
struct irq_alloc_info info;
if (!domain)
return -1;
init_irq_alloc_info(&info, NULL);
info.type = X86_IRQ_ALLOC_TYPE_DMAR;
info.dmar_id = id;
info.dmar_data = arg;
return irq_domain_alloc_irqs(domain, 1, node, &info);
}
void dmar_free_hwirq(int irq)
{
irq_domain_free_irqs(irq, 1);
}
#endif
/*
* MSI message composition
*/
#ifdef CONFIG_HPET_TIMER
static inline int hpet_dev_id(struct irq_domain *domain)
{
struct msi_domain_info *info = msi_get_domain_info(domain);
return (int)(long)info->data;
}
static void hpet_msi_write_msg(struct irq_data *data, struct msi_msg *msg)
{
hpet_msi_write(irq_data_get_irq_handler_data(data), msg);
}
static struct irq_chip hpet_msi_controller __ro_after_init = {
.name = "HPET-MSI",
.irq_unmask = hpet_msi_unmask,
.irq_mask = hpet_msi_mask,
.irq_ack = irq_chip_ack_parent,
.irq_set_affinity = msi_domain_set_affinity,
.irq_retrigger = irq_chip_retrigger_hierarchy,
.irq_compose_msi_msg = irq_msi_compose_msg,
.irq_write_msi_msg = hpet_msi_write_msg,
.flags = IRQCHIP_SKIP_SET_WAKE,
};
static irq_hw_number_t hpet_msi_get_hwirq(struct msi_domain_info *info,
msi_alloc_info_t *arg)
{
return arg->hpet_index;
}
static int hpet_msi_init(struct irq_domain *domain,
struct msi_domain_info *info, unsigned int virq,
irq_hw_number_t hwirq, msi_alloc_info_t *arg)
{
irq_set_status_flags(virq, IRQ_MOVE_PCNTXT);
irq_domain_set_info(domain, virq, arg->hpet_index, info->chip, NULL,
handle_edge_irq, arg->hpet_data, "edge");
return 0;
}
static void hpet_msi_free(struct irq_domain *domain,
struct msi_domain_info *info, unsigned int virq)
{
irq_clear_status_flags(virq, IRQ_MOVE_PCNTXT);
}
static struct msi_domain_ops hpet_msi_domain_ops = {
.get_hwirq = hpet_msi_get_hwirq,
.msi_init = hpet_msi_init,
.msi_free = hpet_msi_free,
};
static struct msi_domain_info hpet_msi_domain_info = {
.ops = &hpet_msi_domain_ops,
.chip = &hpet_msi_controller,
};
struct irq_domain *hpet_create_irq_domain(int hpet_id)
{
struct msi_domain_info *domain_info;
struct irq_domain *parent, *d;
struct irq_alloc_info info;
struct fwnode_handle *fn;
if (x86_vector_domain == NULL)
return NULL;
domain_info = kzalloc(sizeof(*domain_info), GFP_KERNEL);
if (!domain_info)
return NULL;
*domain_info = hpet_msi_domain_info;
domain_info->data = (void *)(long)hpet_id;
init_irq_alloc_info(&info, NULL);
info.type = X86_IRQ_ALLOC_TYPE_HPET;
info.hpet_id = hpet_id;
parent = irq_remapping_get_ir_irq_domain(&info);
if (parent == NULL)
parent = x86_vector_domain;
else
hpet_msi_controller.name = "IR-HPET-MSI";
fn = irq_domain_alloc_named_id_fwnode(hpet_msi_controller.name,
hpet_id);
if (!fn) {
kfree(domain_info);
return NULL;
}
d = msi_create_irq_domain(fn, domain_info, parent);
if (!d) {
irq_domain_free_fwnode(fn);
kfree(domain_info);
}
return d;
}
int hpet_assign_irq(struct irq_domain *domain, struct hpet_channel *hc,
int dev_num)
{
struct irq_alloc_info info;
init_irq_alloc_info(&info, NULL);
info.type = X86_IRQ_ALLOC_TYPE_HPET;
info.hpet_data = hc;
info.hpet_id = hpet_dev_id(domain);
info.hpet_index = dev_num;
return irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, &info);
}
#endif