text: #ifndef LINUX_MSI_H
  #define LINUX_MSI_H
  
  #include <linux/kobject.h>
  #include <linux/list.h>
  
  struct msi_msg {
  	u32	address_lo;	/* low 32 bits of msi message address */
  	u32	address_hi;	/* high 32 bits of msi message address */
  	u32	data;		/* 16 bits of msi message data */
  };
  
  /* Helper functions */
  struct irq_data;
  struct msi_desc;
  void mask_msi_irq(struct irq_data *data);
  void unmask_msi_irq(struct irq_data *data);
  void __read_msi_msg(struct msi_desc *entry, struct msi_msg *msg);
  void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg);
  void __write_msi_msg(struct msi_desc *entry, struct msi_msg *msg);
  void read_msi_msg(unsigned int irq, struct msi_msg *msg);
  void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg);
  void write_msi_msg(unsigned int irq, struct msi_msg *msg);
  
  struct msi_desc {
  	struct {
  		__u8	is_msix	: 1;
  		__u8	multiple: 3;	/* log2 num of messages allocated */
  		__u8	multi_cap : 3;	/* log2 num of messages supported */
  		__u8	maskbit	: 1;	/* mask-pending bit supported ? */
  		__u8	is_64	: 1;	/* Address size: 0=32bit 1=64bit */
  		__u16	entry_nr;	/* specific enabled entry */
  		unsigned default_irq;	/* default pre-assigned irq */
  	} msi_attrib;
  
  	u32 masked;			/* mask bits */
  	unsigned int irq;
  	unsigned int nvec_used;		/* number of messages */
  	struct list_head list;
  
  	union {
  		void __iomem *mask_base;
  		u8 mask_pos;
  	};
  	struct pci_dev *dev;
  
  	/* Last set MSI message */
  	struct msi_msg msg;
  };
  
  /*
   * The arch hooks to setup up msi irqs. Those functions are
   * implemented as weak symbols so that they /can/ be overriden by
   * architecture specific code if needed.
   */
  int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc);
  void arch_teardown_msi_irq(unsigned int irq);
  int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type);
  void arch_teardown_msi_irqs(struct pci_dev *dev);
  void arch_restore_msi_irqs(struct pci_dev *dev);
  
  void default_teardown_msi_irqs(struct pci_dev *dev);
  void default_restore_msi_irqs(struct pci_dev *dev);
  u32 default_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag);
  u32 default_msix_mask_irq(struct msi_desc *desc, u32 flag);
  
  struct msi_chip {
  	struct module *owner;
  	struct device *dev;
  	struct device_node *of_node;
  	struct list_head list;
  
  	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);
  };
  
  #endif /* LINUX_MSI_H */
  