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		30da552428
		
	
	
	
	
		
			
			commit 2ca1af9aa3285c6a5f103ed31ad09f7399fc65d7 "PCI: MSI: Remove
unsafe and unnecessary hardware access" changed read_msi_msg_desc() to
return the last MSI message written instead of reading it from the
device, since it may be called while the device is in a reduced
power state.
However, the pSeries platform code really does need to read messages
from the device, since they are initially written by firmware.
Therefore:
- Restore the previous behaviour of read_msi_msg_desc()
- Add new functions get_cached_msi_msg{,_desc}() which return the
  last MSI message written
- Use the new functions where appropriate
Acked-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
		
	
			
		
			
				
	
	
		
			212 lines
		
	
	
		
			4.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			212 lines
		
	
	
		
			4.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * MSI hooks for standard x86 apic
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|  */
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| 
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| #include <linux/pci.h>
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| #include <linux/irq.h>
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| #include <linux/msi.h>
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| #include <linux/dmar.h>
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| #include <asm/smp.h>
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| #include <asm/msidef.h>
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| 
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| static struct irq_chip	ia64_msi_chip;
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| 
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| #ifdef CONFIG_SMP
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| static int ia64_set_msi_irq_affinity(unsigned int irq,
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| 				      const cpumask_t *cpu_mask)
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| {
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| 	struct msi_msg msg;
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| 	u32 addr, data;
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| 	int cpu = first_cpu(*cpu_mask);
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| 
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| 	if (!cpu_online(cpu))
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| 		return -1;
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| 
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| 	if (irq_prepare_move(irq, cpu))
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| 		return -1;
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| 
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| 	get_cached_msi_msg(irq, &msg);
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| 
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| 	addr = msg.address_lo;
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| 	addr &= MSI_ADDR_DEST_ID_MASK;
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| 	addr |= MSI_ADDR_DEST_ID_CPU(cpu_physical_id(cpu));
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| 	msg.address_lo = addr;
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| 
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| 	data = msg.data;
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| 	data &= MSI_DATA_VECTOR_MASK;
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| 	data |= MSI_DATA_VECTOR(irq_to_vector(irq));
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| 	msg.data = data;
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| 
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| 	write_msi_msg(irq, &msg);
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| 	cpumask_copy(irq_desc[irq].affinity, cpumask_of(cpu));
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| 
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| 	return 0;
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| }
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| #endif /* CONFIG_SMP */
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| 
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| int ia64_setup_msi_irq(struct pci_dev *pdev, struct msi_desc *desc)
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| {
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| 	struct msi_msg	msg;
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| 	unsigned long	dest_phys_id;
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| 	int	irq, vector;
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| 	cpumask_t mask;
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| 
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| 	irq = create_irq();
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| 	if (irq < 0)
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| 		return irq;
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| 
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| 	set_irq_msi(irq, desc);
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| 	cpus_and(mask, irq_to_domain(irq), cpu_online_map);
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| 	dest_phys_id = cpu_physical_id(first_cpu(mask));
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| 	vector = irq_to_vector(irq);
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| 
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| 	msg.address_hi = 0;
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| 	msg.address_lo =
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| 		MSI_ADDR_HEADER |
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| 		MSI_ADDR_DEST_MODE_PHYS |
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| 		MSI_ADDR_REDIRECTION_CPU |
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| 		MSI_ADDR_DEST_ID_CPU(dest_phys_id);
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| 
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| 	msg.data =
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| 		MSI_DATA_TRIGGER_EDGE |
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| 		MSI_DATA_LEVEL_ASSERT |
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| 		MSI_DATA_DELIVERY_FIXED |
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| 		MSI_DATA_VECTOR(vector);
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| 
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| 	write_msi_msg(irq, &msg);
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| 	set_irq_chip_and_handler(irq, &ia64_msi_chip, handle_edge_irq);
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| 
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| 	return 0;
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| }
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| 
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| void ia64_teardown_msi_irq(unsigned int irq)
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| {
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| 	destroy_irq(irq);
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| }
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| 
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| static void ia64_ack_msi_irq(unsigned int irq)
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| {
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| 	irq_complete_move(irq);
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| 	move_native_irq(irq);
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| 	ia64_eoi();
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| }
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| 
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| static int ia64_msi_retrigger_irq(unsigned int irq)
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| {
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| 	unsigned int vector = irq_to_vector(irq);
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| 	ia64_resend_irq(vector);
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| 
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| 	return 1;
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| }
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| 
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| /*
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|  * Generic ops used on most IA64 platforms.
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|  */
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| static struct irq_chip ia64_msi_chip = {
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| 	.name		= "PCI-MSI",
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| 	.mask		= mask_msi_irq,
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| 	.unmask		= unmask_msi_irq,
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| 	.ack		= ia64_ack_msi_irq,
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| #ifdef CONFIG_SMP
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| 	.set_affinity	= ia64_set_msi_irq_affinity,
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| #endif
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| 	.retrigger	= ia64_msi_retrigger_irq,
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| };
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| 
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| 
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| int arch_setup_msi_irq(struct pci_dev *pdev, struct msi_desc *desc)
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| {
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| 	if (platform_setup_msi_irq)
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| 		return platform_setup_msi_irq(pdev, desc);
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| 
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| 	return ia64_setup_msi_irq(pdev, desc);
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| }
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| 
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| void arch_teardown_msi_irq(unsigned int irq)
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| {
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| 	if (platform_teardown_msi_irq)
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| 		return platform_teardown_msi_irq(irq);
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| 
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| 	return ia64_teardown_msi_irq(irq);
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| }
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| 
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| #ifdef CONFIG_DMAR
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| #ifdef CONFIG_SMP
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| static int dmar_msi_set_affinity(unsigned int irq, const struct cpumask *mask)
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| {
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| 	struct irq_cfg *cfg = irq_cfg + irq;
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| 	struct msi_msg msg;
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| 	int cpu = cpumask_first(mask);
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| 
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| 	if (!cpu_online(cpu))
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| 		return -1;
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| 
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| 	if (irq_prepare_move(irq, cpu))
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| 		return -1;
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| 
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| 	dmar_msi_read(irq, &msg);
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| 
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| 	msg.data &= ~MSI_DATA_VECTOR_MASK;
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| 	msg.data |= MSI_DATA_VECTOR(cfg->vector);
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| 	msg.address_lo &= ~MSI_ADDR_DEST_ID_MASK;
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| 	msg.address_lo |= MSI_ADDR_DEST_ID_CPU(cpu_physical_id(cpu));
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| 
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| 	dmar_msi_write(irq, &msg);
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| 	cpumask_copy(irq_desc[irq].affinity, mask);
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| 
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| 	return 0;
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| }
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| #endif /* CONFIG_SMP */
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| 
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| static struct irq_chip dmar_msi_type = {
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| 	.name = "DMAR_MSI",
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| 	.unmask = dmar_msi_unmask,
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| 	.mask = dmar_msi_mask,
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| 	.ack = ia64_ack_msi_irq,
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| #ifdef CONFIG_SMP
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| 	.set_affinity = dmar_msi_set_affinity,
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| #endif
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| 	.retrigger = ia64_msi_retrigger_irq,
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| };
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| 
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| static int
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| msi_compose_msg(struct pci_dev *pdev, unsigned int irq, struct msi_msg *msg)
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| {
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| 	struct irq_cfg *cfg = irq_cfg + irq;
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| 	unsigned dest;
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| 	cpumask_t mask;
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| 
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| 	cpus_and(mask, irq_to_domain(irq), cpu_online_map);
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| 	dest = cpu_physical_id(first_cpu(mask));
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| 
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| 	msg->address_hi = 0;
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| 	msg->address_lo =
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| 		MSI_ADDR_HEADER |
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| 		MSI_ADDR_DEST_MODE_PHYS |
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| 		MSI_ADDR_REDIRECTION_CPU |
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| 		MSI_ADDR_DEST_ID_CPU(dest);
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| 
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| 	msg->data =
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| 		MSI_DATA_TRIGGER_EDGE |
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| 		MSI_DATA_LEVEL_ASSERT |
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| 		MSI_DATA_DELIVERY_FIXED |
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| 		MSI_DATA_VECTOR(cfg->vector);
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| 	return 0;
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| }
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| 
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| int arch_setup_dmar_msi(unsigned int irq)
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| {
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| 	int ret;
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| 	struct msi_msg msg;
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| 
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| 	ret = msi_compose_msg(NULL, irq, &msg);
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| 	if (ret < 0)
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| 		return ret;
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| 	dmar_msi_write(irq, &msg);
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| 	set_irq_chip_and_handler_name(irq, &dmar_msi_type, handle_edge_irq,
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| 		"edge");
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| 	return 0;
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| }
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| #endif /* CONFIG_DMAR */
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| 
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