xen: map MSIs into pirqs

Map MSIs into pirqs, writing 0 in the MSI vector data field and the pirq
number in the MSI destination id field.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This commit is contained in:
Stefano Stabellini 2010-07-01 17:10:39 +01:00
parent 3942b740e5
commit 809f9267bb
3 changed files with 81 additions and 0 deletions

View File

@ -64,10 +64,62 @@ static int acpi_register_gsi_xen_hvm(struct device *dev, u32 gsi,
#if defined(CONFIG_PCI_MSI)
#include <linux/msi.h>
#include <asm/msidef.h>
struct xen_pci_frontend_ops *xen_pci_frontend;
EXPORT_SYMBOL_GPL(xen_pci_frontend);
static void xen_msi_compose_msg(struct pci_dev *pdev, unsigned int pirq,
struct msi_msg *msg)
{
/* We set vector == 0 to tell the hypervisor we don't care about it,
* but we want a pirq setup instead.
* We use the dest_id field to pass the pirq that we want. */
msg->address_hi = MSI_ADDR_BASE_HI | MSI_ADDR_EXT_DEST_ID(pirq);
msg->address_lo =
MSI_ADDR_BASE_LO |
MSI_ADDR_DEST_MODE_PHYSICAL |
MSI_ADDR_REDIRECTION_CPU |
MSI_ADDR_DEST_ID(pirq);
msg->data =
MSI_DATA_TRIGGER_EDGE |
MSI_DATA_LEVEL_ASSERT |
/* delivery mode reserved */
(3 << 8) |
MSI_DATA_VECTOR(0);
}
static int xen_hvm_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
{
int irq, pirq, ret = 0;
struct msi_desc *msidesc;
struct msi_msg msg;
list_for_each_entry(msidesc, &dev->msi_list, list) {
xen_allocate_pirq_msi((type == PCI_CAP_ID_MSIX) ?
"msi-x" : "msi", &irq, &pirq);
if (irq < 0 || pirq < 0)
goto error;
printk(KERN_DEBUG "xen: msi --> irq=%d, pirq=%d\n", irq, pirq);
xen_msi_compose_msg(dev, pirq, &msg);
ret = set_irq_msi(irq, msidesc);
if (ret < 0)
goto error_while;
write_msi_msg(irq, &msg);
}
return 0;
error_while:
unbind_from_irqhandler(irq, NULL);
error:
if (ret == -ENODEV)
dev_err(&dev->dev, "Xen PCI frontend has not registered" \
" MSI/MSI-X support!\n");
return ret;
}
/*
* For MSI interrupts we have to use drivers/xen/event.s functions to
* allocate an irq_desc and setup the right */
@ -198,5 +250,10 @@ int __init pci_xen_hvm_init(void)
*/
__acpi_register_gsi = acpi_register_gsi_xen_hvm;
#endif
#ifdef CONFIG_PCI_MSI
x86_msi.setup_msi_irqs = xen_hvm_setup_msi_irqs;
x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
#endif
return 0;
}

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@ -656,6 +656,28 @@ int xen_map_pirq_gsi(unsigned pirq, unsigned gsi, int shareable, char *name)
return irq;
}
void xen_allocate_pirq_msi(char *name, int *irq, int *pirq)
{
spin_lock(&irq_mapping_update_lock);
*irq = find_unbound_irq();
if (*irq == -1)
goto out;
*pirq = find_unbound_pirq();
if (*pirq == -1)
goto out;
set_irq_chip_and_handler_name(*irq, &xen_pirq_chip,
handle_level_irq, name);
irq_info[*irq] = mk_pirq_info(0, *pirq, 0, 0);
pirq_to_irq[*pirq] = *irq;
out:
spin_unlock(&irq_mapping_update_lock);
}
int xen_destroy_irq(int irq)
{
struct irq_desc *desc;

View File

@ -72,6 +72,8 @@ void xen_hvm_evtchn_do_upcall(void);
* usual. */
int xen_allocate_pirq(unsigned gsi, int shareable, char *name);
int xen_map_pirq_gsi(unsigned pirq, unsigned gsi, int shareable, char *name);
/* Allocate an irq and a pirq to be used with MSIs. */
void xen_allocate_pirq_msi(char *name, int *irq, int *pirq);
/* De-allocates the above mentioned physical interrupt. */
int xen_destroy_irq(int irq);