/*
 * 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 (reassign_irq_vector(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 irq;
}

void ia64_teardown_msi_irq(unsigned int irq)
{
	destroy_irq(irq);
}

static void ia64_ack_msi_irq(unsigned int 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);
}
