genirq: Add generic msi irq domain support
Implement the basic functions for MSI interrupt support with
hierarchical interrupt domains.
[ tglx: Extracted and combined from several patches ]
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/linux/msi.h b/include/linux/msi.h
index e0d0851..b5ca245 100644
--- a/include/linux/msi.h
+++ b/include/linux/msi.h
@@ -114,4 +114,49 @@
void (*teardown_irq)(struct msi_controller *chip, unsigned int irq);
};
+#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
+struct irq_domain;
+struct irq_chip;
+struct device_node;
+struct msi_domain_info;
+
+/**
+ * struct msi_domain_ops - MSI interrupt domain callbacks
+ * @get_hwirq: Retrieve the resulting hw irq number
+ * @msi_init: Domain specific init function for MSI interrupts
+ * @msi_free: Domain specific function to free a MSI interrupts
+ */
+struct msi_domain_ops {
+ irq_hw_number_t (*get_hwirq)(struct msi_domain_info *info, void *arg);
+ int (*msi_init)(struct irq_domain *domain,
+ struct msi_domain_info *info,
+ unsigned int virq, irq_hw_number_t hwirq,
+ void *arg);
+ void (*msi_free)(struct irq_domain *domain,
+ struct msi_domain_info *info,
+ unsigned int virq);
+};
+
+/**
+ * struct msi_domain_info - MSI interrupt domain data
+ * @ops: The callback data structure
+ * @chip: The associated interrupt chip
+ * @data: Domain specific data
+ */
+struct msi_domain_info {
+ struct msi_domain_ops *ops;
+ struct irq_chip *chip;
+ void *data;
+};
+
+int msi_domain_set_affinity(struct irq_data *data, const struct cpumask *mask,
+ bool force);
+
+struct irq_domain *msi_create_irq_domain(struct device_node *of_node,
+ struct msi_domain_info *info,
+ struct irq_domain *parent);
+struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain);
+
+#endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */
+
#endif /* LINUX_MSI_H */
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
index 4f2eb2b..9a76e3b 100644
--- a/kernel/irq/Kconfig
+++ b/kernel/irq/Kconfig
@@ -60,6 +60,16 @@
bool
select IRQ_DOMAIN
+# Generic MSI interrupt support
+config GENERIC_MSI_IRQ
+ bool
+
+# Generic MSI hierarchical interrupt domain support
+config GENERIC_MSI_IRQ_DOMAIN
+ bool
+ select IRQ_DOMAIN_HIERARCHY
+ select GENERIC_MSI_IRQ
+
config HANDLE_DOMAIN_IRQ
bool
diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile
index fff1738..d121235 100644
--- a/kernel/irq/Makefile
+++ b/kernel/irq/Makefile
@@ -6,3 +6,4 @@
obj-$(CONFIG_PROC_FS) += proc.o
obj-$(CONFIG_GENERIC_PENDING_IRQ) += migration.o
obj-$(CONFIG_PM_SLEEP) += pm.o
+obj-$(CONFIG_GENERIC_MSI_IRQ) += msi.o
diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
new file mode 100644
index 0000000..5e0cef4
--- /dev/null
+++ b/kernel/irq/msi.c
@@ -0,0 +1,141 @@
+/*
+ * linux/kernel/irq/msi.c
+ *
+ * Copyright (C) 2014 Intel Corp.
+ * Author: Jiang Liu <jiang.liu@linux.intel.com>
+ *
+ * This file is licensed under GPLv2.
+ *
+ * This file contains common code to support Message Signalled Interrupt for
+ * PCI compatible and non PCI compatible devices.
+ */
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/msi.h>
+
+#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
+/**
+ * msi_domain_set_affinity - Generic affinity setter function for MSI domains
+ * @irq_data: The irq data associated to the interrupt
+ * @mask: The affinity mask to set
+ * @force: Flag to enforce setting (disable online checks)
+ *
+ * Intended to be used by MSI interrupt controllers which are
+ * implemented with hierarchical domains.
+ */
+int msi_domain_set_affinity(struct irq_data *irq_data,
+ const struct cpumask *mask, bool force)
+{
+ struct irq_data *parent = irq_data->parent_data;
+ struct msi_msg msg;
+ int ret;
+
+ ret = parent->chip->irq_set_affinity(parent, mask, force);
+ if (ret >= 0 && ret != IRQ_SET_MASK_OK_DONE) {
+ BUG_ON(irq_chip_compose_msi_msg(irq_data, &msg));
+ irq_chip_write_msi_msg(irq_data, &msg);
+ }
+
+ return ret;
+}
+
+static void msi_domain_activate(struct irq_domain *domain,
+ struct irq_data *irq_data)
+{
+ struct msi_msg msg;
+
+ BUG_ON(irq_chip_compose_msi_msg(irq_data, &msg));
+ irq_chip_write_msi_msg(irq_data, &msg);
+}
+
+static void msi_domain_deactivate(struct irq_domain *domain,
+ struct irq_data *irq_data)
+{
+ struct msi_msg msg;
+
+ memset(&msg, 0, sizeof(msg));
+ irq_chip_write_msi_msg(irq_data, &msg);
+}
+
+static int msi_domain_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *arg)
+{
+ struct msi_domain_info *info = domain->host_data;
+ struct msi_domain_ops *ops = info->ops;
+ irq_hw_number_t hwirq = ops->get_hwirq(info, arg);
+ int i, ret;
+
+ if (irq_find_mapping(domain, hwirq) > 0)
+ return -EEXIST;
+
+ ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg);
+ if (ret < 0)
+ return ret;
+
+ for (i = 0; i < nr_irqs; i++) {
+ ret = ops->msi_init(domain, info, virq + i, hwirq + i, arg);
+ if (ret < 0) {
+ if (ops->msi_free) {
+ for (i--; i > 0; i--)
+ ops->msi_free(domain, info, virq + i);
+ }
+ irq_domain_free_irqs_top(domain, virq, nr_irqs);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static void msi_domain_free(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs)
+{
+ struct msi_domain_info *info = domain->host_data;
+ int i;
+
+ if (info->ops->msi_free) {
+ for (i = 0; i < nr_irqs; i++)
+ info->ops->msi_free(domain, info, virq + i);
+ }
+ irq_domain_free_irqs_top(domain, virq, nr_irqs);
+}
+
+static struct irq_domain_ops msi_domain_ops = {
+ .alloc = msi_domain_alloc,
+ .free = msi_domain_free,
+ .activate = msi_domain_activate,
+ .deactivate = msi_domain_deactivate,
+};
+
+/**
+ * msi_create_irq_domain - Create a MSI interrupt domain
+ * @of_node: Optional device-tree node of the interrupt controller
+ * @info: MSI domain info
+ * @parent: Parent irq domain
+ */
+struct irq_domain *msi_create_irq_domain(struct device_node *of_node,
+ struct msi_domain_info *info,
+ struct irq_domain *parent)
+{
+ struct irq_domain *domain;
+
+ domain = irq_domain_add_tree(of_node, &msi_domain_ops, info);
+ if (domain)
+ domain->parent = parent;
+
+ return domain;
+}
+
+/**
+ * msi_get_domain_info - Get the MSI interrupt domain info for @domain
+ * @domain: The interrupt domain to retrieve data from
+ *
+ * Returns the pointer to the msi_domain_info stored in
+ * @domain->host_data.
+ */
+struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain)
+{
+ return (struct msi_domain_info *)domain->host_data;
+}
+
+#endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */