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linux/arch/ia64/kernel/msi_ia64.c
Kenji Kaneshige a6cd6322d5 [IA64] Fix irq migration in multiple vector domain
Fix the problem that the following error message is sometimes displayed
at irq migration when vector domain is enabled.

    "Unexpected interrupt vector %d on CPU %d is not mapped to any IRQ!"

The cause of this problem is an interrupt is sent to the previous
target CPU after cleaning up vector to irq mapping table. To clean up
vector to irq map on the previous target CPU safty, change the irq
migration in multiple vector domain as follows. The original idea is
from x86 interrupt management code.

    - Delay vector to irq table cleanup until the interrupts are sent
      to new target CPUs. By this, it is ensured that target CPU is
      completely changed on the interrupt controller side.

    - Even after the interrupts are sent to new target CPUs, there can
      be pended interrupts remaining on the previous target CPU. So we
      need to delay clearning up vector to irq table until the pended
      interrupt is handled. For this, send IPI to the previous target
      CPU with lower priority vector and clean up vector to irq table
      in its handler.

This patch affects only to irq migration code with multiple vector
domain is enabled.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2008-03-04 14:16:20 -08:00

165 lines
3.7 KiB
C

/*
* MSI hooks for standard x86 apic
*/
#include <linux/pci.h>
#include <linux/irq.h>
#include <linux/msi.h>
#include <asm/smp.h>
/*
* Shifts for APIC-based data
*/
#define MSI_DATA_VECTOR_SHIFT 0
#define MSI_DATA_VECTOR(v) (((u8)v) << MSI_DATA_VECTOR_SHIFT)
#define MSI_DATA_VECTOR_MASK 0xffffff00
#define MSI_DATA_DELIVERY_SHIFT 8
#define MSI_DATA_DELIVERY_FIXED (0 << MSI_DATA_DELIVERY_SHIFT)
#define MSI_DATA_DELIVERY_LOWPRI (1 << MSI_DATA_DELIVERY_SHIFT)
#define MSI_DATA_LEVEL_SHIFT 14
#define MSI_DATA_LEVEL_DEASSERT (0 << MSI_DATA_LEVEL_SHIFT)
#define MSI_DATA_LEVEL_ASSERT (1 << MSI_DATA_LEVEL_SHIFT)
#define MSI_DATA_TRIGGER_SHIFT 15
#define MSI_DATA_TRIGGER_EDGE (0 << MSI_DATA_TRIGGER_SHIFT)
#define MSI_DATA_TRIGGER_LEVEL (1 << MSI_DATA_TRIGGER_SHIFT)
/*
* Shift/mask fields for APIC-based bus address
*/
#define MSI_TARGET_CPU_SHIFT 4
#define MSI_ADDR_HEADER 0xfee00000
#define MSI_ADDR_DESTID_MASK 0xfff0000f
#define MSI_ADDR_DESTID_CPU(cpu) ((cpu) << MSI_TARGET_CPU_SHIFT)
#define MSI_ADDR_DESTMODE_SHIFT 2
#define MSI_ADDR_DESTMODE_PHYS (0 << MSI_ADDR_DESTMODE_SHIFT)
#define MSI_ADDR_DESTMODE_LOGIC (1 << MSI_ADDR_DESTMODE_SHIFT)
#define MSI_ADDR_REDIRECTION_SHIFT 3
#define MSI_ADDR_REDIRECTION_CPU (0 << MSI_ADDR_REDIRECTION_SHIFT)
#define MSI_ADDR_REDIRECTION_LOWPRI (1 << MSI_ADDR_REDIRECTION_SHIFT)
static struct irq_chip ia64_msi_chip;
#ifdef CONFIG_SMP
static void ia64_set_msi_irq_affinity(unsigned int irq, cpumask_t cpu_mask)
{
struct msi_msg msg;
u32 addr, data;
int cpu = first_cpu(cpu_mask);
if (!cpu_online(cpu))
return;
if (irq_prepare_move(irq, cpu))
return;
read_msi_msg(irq, &msg);
addr = msg.address_lo;
addr &= MSI_ADDR_DESTID_MASK;
addr |= MSI_ADDR_DESTID_CPU(cpu_physical_id(cpu));
msg.address_lo = addr;
data = msg.data;
data &= MSI_DATA_VECTOR_MASK;
data |= MSI_DATA_VECTOR(irq_to_vector(irq));
msg.data = data;
write_msi_msg(irq, &msg);
irq_desc[irq].affinity = cpumask_of_cpu(cpu);
}
#endif /* CONFIG_SMP */
int ia64_setup_msi_irq(struct pci_dev *pdev, struct msi_desc *desc)
{
struct msi_msg msg;
unsigned long dest_phys_id;
int irq, vector;
cpumask_t mask;
irq = create_irq();
if (irq < 0)
return irq;
set_irq_msi(irq, desc);
cpus_and(mask, irq_to_domain(irq), cpu_online_map);
dest_phys_id = cpu_physical_id(first_cpu(mask));
vector = irq_to_vector(irq);
msg.address_hi = 0;
msg.address_lo =
MSI_ADDR_HEADER |
MSI_ADDR_DESTMODE_PHYS |
MSI_ADDR_REDIRECTION_CPU |
MSI_ADDR_DESTID_CPU(dest_phys_id);
msg.data =
MSI_DATA_TRIGGER_EDGE |
MSI_DATA_LEVEL_ASSERT |
MSI_DATA_DELIVERY_FIXED |
MSI_DATA_VECTOR(vector);
write_msi_msg(irq, &msg);
set_irq_chip_and_handler(irq, &ia64_msi_chip, handle_edge_irq);
return 0;
}
void ia64_teardown_msi_irq(unsigned int irq)
{
destroy_irq(irq);
}
static void ia64_ack_msi_irq(unsigned int irq)
{
irq_complete_move(irq);
move_native_irq(irq);
ia64_eoi();
}
static int ia64_msi_retrigger_irq(unsigned int irq)
{
unsigned int vector = irq_to_vector(irq);
ia64_resend_irq(vector);
return 1;
}
/*
* Generic ops used on most IA64 platforms.
*/
static struct irq_chip ia64_msi_chip = {
.name = "PCI-MSI",
.mask = mask_msi_irq,
.unmask = unmask_msi_irq,
.ack = ia64_ack_msi_irq,
#ifdef CONFIG_SMP
.set_affinity = ia64_set_msi_irq_affinity,
#endif
.retrigger = ia64_msi_retrigger_irq,
};
int arch_setup_msi_irq(struct pci_dev *pdev, struct msi_desc *desc)
{
if (platform_setup_msi_irq)
return platform_setup_msi_irq(pdev, desc);
return ia64_setup_msi_irq(pdev, desc);
}
void arch_teardown_msi_irq(unsigned int irq)
{
if (platform_teardown_msi_irq)
return platform_teardown_msi_irq(irq);
return ia64_teardown_msi_irq(irq);
}