From 9c6ddccbbfaf789beccc6a1d87abe9bc60dc570f Mon Sep 17 00:00:00 2001 From: Thierry Reding Date: Thu, 6 Jun 2013 18:20:29 +0200 Subject: [PATCH 072/203] PCI: Introduce new MSI chip infrastructure The new struct msi_chip is used to associated an MSI controller with a PCI bus. It is automatically handed down from the root to its children during bus enumeration. This patch provides default (weak) implementations for the architecture- specific MSI functions (arch_setup_msi_irq(), arch_teardown_msi_irq() and arch_msi_check_device()) which check if a PCI device's bus has an attached MSI chip and forward the call appropriately. Signed-off-by: Thierry Reding Signed-off-by: Thomas Petazzoni Acked-by: Bjorn Helgaas Tested-by: Daniel Price Tested-by: Thierry Reding --- drivers/pci/msi.c | 27 +++++++++++++++++++++++++-- drivers/pci/probe.c | 1 + include/linux/msi.h | 11 +++++++++++ include/linux/pci.h | 1 + 4 files changed, 38 insertions(+), 2 deletions(-) --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -32,16 +32,39 @@ static int pci_msi_enable = 1; int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc) { - return -EINVAL; + struct msi_chip *chip = dev->bus->msi; + int err; + + if (!chip || !chip->setup_irq) + return -EINVAL; + + err = chip->setup_irq(chip, dev, desc); + if (err < 0) + return err; + + irq_set_chip_data(desc->irq, chip); + + return 0; } void __weak arch_teardown_msi_irq(unsigned int irq) { + struct msi_chip *chip = irq_get_chip_data(irq); + + if (!chip || !chip->teardown_irq) + return; + + chip->teardown_irq(chip, irq); } int __weak arch_msi_check_device(struct pci_dev *dev, int nvec, int type) { - return 0; + struct msi_chip *chip = dev->bus->msi; + + if (!chip || !chip->check_device) + return 0; + + return chip->check_device(chip, dev, nvec, type); } int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -634,6 +634,7 @@ static struct pci_bus *pci_alloc_child_b child->parent = parent; child->ops = parent->ops; + child->msi = parent->msi; child->sysdata = parent->sysdata; child->bus_flags = parent->bus_flags; --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -64,4 +64,15 @@ void arch_restore_msi_irqs(struct pci_de void default_teardown_msi_irqs(struct pci_dev *dev); void default_restore_msi_irqs(struct pci_dev *dev, int irq); +struct msi_chip { + struct module *owner; + struct device *dev; + + int (*setup_irq)(struct msi_chip *chip, struct pci_dev *dev, + struct msi_desc *desc); + void (*teardown_irq)(struct msi_chip *chip, unsigned int irq); + int (*check_device)(struct msi_chip *chip, struct pci_dev *dev, + int nvec, int type); +}; + #endif /* LINUX_MSI_H */ --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -432,6 +432,7 @@ struct pci_bus { struct resource busn_res; /* bus numbers routed to this bus */ struct pci_ops *ops; /* configuration access functions */ + struct msi_chip *msi; /* MSI controller */ void *sysdata; /* hook for sys-specific extension */ struct proc_dir_entry *procdir; /* directory entry in /proc/bus/pci */