From 809f9267bbaba7765cdb86a47f2e6e4bf4951b69 Mon Sep 17 00:00:00 2001 From: Stefano Stabellini Date: Thu, 1 Jul 2010 17:10:39 +0100 Subject: 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 Reviewed-by: Konrad Rzeszutek Wilk --- arch/x86/pci/xen.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++++ drivers/xen/events.c | 22 ++++++++++++++++++++ include/xen/events.h | 2 ++ 3 files changed, 81 insertions(+) diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c index d5284c491aef..b5bd6420851e 100644 --- a/arch/x86/pci/xen.c +++ b/arch/x86/pci/xen.c @@ -64,10 +64,62 @@ static int acpi_register_gsi_xen_hvm(struct device *dev, u32 gsi, #if defined(CONFIG_PCI_MSI) #include +#include 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; } diff --git a/drivers/xen/events.c b/drivers/xen/events.c index 32269bcbd88c..efa683ee8840 100644 --- a/drivers/xen/events.c +++ b/drivers/xen/events.c @@ -656,6 +656,28 @@ out: 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; diff --git a/include/xen/events.h b/include/xen/events.h index deec8faace22..0c58db6ea3f4 100644 --- a/include/xen/events.h +++ b/include/xen/events.h @@ -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); -- cgit v1.2.3-59-g8ed1b