[patch V2 18/36] genirq/msi: Add msi_device_data::properties

Thomas Gleixner
2021-12-06T22:40:25Z

Add a properties field which allows core code to store information for easy
retrieval in order to replace MSI descriptor fiddling.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
V2: Add a setter function to prepare for future changes
---
include/linux/msi.h | 17 +++++++++++++++++
kernel/irq/msi.c | 24 ++++++++++++++++++++++++
2 files changed, 41 insertions(+)

--- a/include/linux/msi.h
+++ b/include/linux/msi.h
@@ -4,6 +4,7 @@

#include <linux/cpumask.h>
#include <linux/list.h>
+#include <linux/bits.h>
#include <asm/msi.h>

/* Dummy shadow structures if an architecture does not define them */
@@ -153,6 +154,22 @@ struct msi_device_data {

int msi_setup_device_data(struct device *dev);

+/* MSI device properties */
+#define MSI_PROP_PCI_MSI BIT(0)
+#define MSI_PROP_PCI_MSIX BIT(1)
+#define MSI_PROP_64BIT BIT(2)
+
+#ifdef CONFIG_GENERIC_MSI_IRQ
+bool msi_device_has_property(struct device *dev, unsigned long prop);
+void msi_device_set_properties(struct device *dev, unsigned long prop);
+#else
+static inline bool msi_device_has_property(struct device *dev, unsigned long prop)
+{
+ return false;
+}
+static inline void msi_device_set_properties(struct device *dev, unsigned long prop) { }
+#endif
+
/* Helpers to hide struct msi_desc implementation details */
#define msi_desc_to_dev(desc) ((desc)->dev)
#define dev_to_msi_list(dev) (&(dev)->msi_list)
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -60,6 +60,30 @@ void free_msi_entry(struct msi_desc *ent
kfree(entry);
}

+/**
+ * msi_device_set_properties - Set device specific MSI properties
+ * @dev: Pointer to the device which is queried
+ * @prop: Properties to set
+ */
+void msi_device_set_properties(struct device *dev, unsigned long prop)
+{
+ if (WARN_ON_ONCE(!dev->msi.data))
+ return ;
+ dev->msi.data->properties = 0;
+}
+
+/**
+ * msi_device_has_property - Check whether a device has a specific MSI property
+ * @dev: Pointer to the device which is queried
+ * @prop: Property to check for
+ */
+bool msi_device_has_property(struct device *dev, unsigned long prop)
+{
+ if (!dev->msi.data)
+ return false;
+ return !!(dev->msi.data->properties & prop);
+}
+
void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
{
*msg = entry->msg;