linux-stable/arch/x86/kernel/apic/msi.c
Thomas Gleixner b3f8236411 x86/apic/msi: Use PCI device MSI property
instead of fiddling with MSI descriptors.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20211210221813.372357371@linutronix.de
2021-12-16 22:16:37 +01:00

350 lines
9.9 KiB
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/hpet.h>
#include <asm/hw_irq.h>
#include <asm/apic.h>
#include <asm/irq_remapping.h>
#include <asm/xen/hypervisor.h>
struct irq_domain *x86_pci_msi_default_domain __ro_after_init;
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, false);
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 interrupt is not yet started 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 ||
!irqd_is_started(irqd) ||
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_set_affinity = msi_set_affinity,
.flags = IRQCHIP_SKIP_SET_WAKE |
IRQCHIP_AFFINITY_PRE_STARTUP,
};
int pci_msi_prepare(struct irq_domain *domain, struct device *dev, int nvec,
msi_alloc_info_t *arg)
{
init_irq_alloc_info(arg, NULL);
if (to_pci_dev(dev)->msix_enabled) {
arg->type = X86_IRQ_ALLOC_TYPE_PCI_MSIX;
} else {
arg->type = X86_IRQ_ALLOC_TYPE_PCI_MSI;
arg->flags |= X86_IRQ_ALLOC_CONTIGUOUS_VECTORS;
}
return 0;
}
EXPORT_SYMBOL_GPL(pci_msi_prepare);
static struct msi_domain_ops pci_msi_domain_ops = {
.msi_prepare = pci_msi_prepare,
};
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",
};
struct irq_domain * __init native_create_pci_msi_domain(void)
{
struct fwnode_handle *fn;
struct irq_domain *d;
if (disable_apic)
return NULL;
fn = irq_domain_alloc_named_fwnode("PCI-MSI");
if (!fn)
return NULL;
d = pci_msi_create_irq_domain(fn, &pci_msi_domain_info,
x86_vector_domain);
if (!d) {
irq_domain_free_fwnode(fn);
pr_warn("Failed to initialize PCI-MSI irqdomain.\n");
} else {
d->flags |= IRQ_DOMAIN_MSI_NOMASK_QUIRK;
}
return d;
}
void __init x86_create_pci_msi_domain(void)
{
x86_pci_msi_default_domain = x86_init.irqs.create_pci_msi_domain();
}
#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,
.flags = IRQCHIP_SKIP_SET_WAKE |
IRQCHIP_AFFINITY_PRE_STARTUP,
};
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
/*
* The Intel IOMMU (ab)uses the high bits of the MSI address to contain the
* high bits of the destination APIC ID. This can't be done in the general
* case for MSIs as it would be targeting real memory above 4GiB not the
* APIC.
*/
static void dmar_msi_compose_msg(struct irq_data *data, struct msi_msg *msg)
{
__irq_msi_compose_msg(irqd_cfg(data), msg, true);
}
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 = dmar_msi_compose_msg,
.irq_write_msi_msg = dmar_msi_write_msg,
.flags = IRQCHIP_SKIP_SET_WAKE |
IRQCHIP_AFFINITY_PRE_STARTUP,
};
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->devid, info->chip, NULL,
handle_edge_irq, arg->data, "edge");
return 0;
}
static struct msi_domain_ops dmar_msi_domain_ops = {
.msi_init = dmar_msi_init,
};
static struct msi_domain_info dmar_msi_domain_info = {
.ops = &dmar_msi_domain_ops,
.chip = &dmar_msi_controller,
.flags = MSI_FLAG_USE_DEF_DOM_OPS,
};
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.devid = id;
info.hwirq = id;
info.data = arg;
return irq_domain_alloc_irqs(domain, 1, node, &info);
}
void dmar_free_hwirq(int irq)
{
irq_domain_free_irqs(irq, 1);
}
#endif
bool arch_restore_msi_irqs(struct pci_dev *dev)
{
return xen_initdom_restore_msi(dev);
}