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authorLinus Torvalds <torvalds@linux-foundation.org>2014-12-10 09:01:01 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2014-12-10 09:01:01 -0800
commit9e66645d72d3c395da92b0f8855c787f4b5f0e89 (patch)
tree61b94adb6c32340c45b6d984837556b6b845e983 /kernel/irq/msi.c
parentecb50f0afd35a51ef487e8a54b976052eb03d729 (diff)
parent74faaf7aa64c76b60db0f5c994fd43a46be772ce (diff)
downloadlinux-9e66645d72d3c395da92b0f8855c787f4b5f0e89.tar.bz2
Merge branch 'irq-irqdomain-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq domain updates from Thomas Gleixner: "The real interesting irq updates: - Support for hierarchical irq domains: For complex interrupt routing scenarios where more than one interrupt related chip is involved we had no proper representation in the generic interrupt infrastructure so far. That made people implement rather ugly constructs in their nested irq chip implementations. The main offenders are x86 and arm/gic. To distangle that mess we have now hierarchical irqdomains which seperate the various interrupt chips and connect them via the hierarchical domains. That keeps the domain specific details internal to the particular hierarchy level and removes the criss/cross referencing of chip internals. The resulting hierarchy for a complex x86 system will look like this: vector mapped: 74 msi-0 mapped: 2 dmar-ir-1 mapped: 69 ioapic-1 mapped: 4 ioapic-0 mapped: 20 pci-msi-2 mapped: 45 dmar-ir-0 mapped: 3 ioapic-2 mapped: 1 pci-msi-1 mapped: 2 htirq mapped: 0 Neither ioapic nor pci-msi know about the dmar interrupt remapping between themself and the vector domain. If interrupt remapping is disabled ioapic and pci-msi become direct childs of the vector domain. In hindsight we should have done that years ago, but in hindsight we always know better :) - Support for generic MSI interrupt domain handling We have more and more non PCI related MSI interrupts, so providing a generic infrastructure for this is better than having all affected architectures implementing their own private hacks. - Support for PCI-MSI interrupt domain handling, based on the generic MSI support. This part carries the pci/msi branch from Bjorn Helgaas pci tree to avoid a massive conflict. The PCI/MSI parts are acked by Bjorn. I have two more branches on top of this. The full conversion of x86 to hierarchical domains and a partial conversion of arm/gic" * 'irq-irqdomain-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits) genirq: Move irq_chip_write_msi_msg() helper to core PCI/MSI: Allow an msi_controller to be associated to an irq domain PCI/MSI: Provide mechanism to alloc/free MSI/MSIX interrupt from irqdomain PCI/MSI: Enhance core to support hierarchy irqdomain PCI/MSI: Move cached entry functions to irq core genirq: Provide default callbacks for msi_domain_ops genirq: Introduce msi_domain_alloc/free_irqs() asm-generic: Add msi.h genirq: Add generic msi irq domain support genirq: Introduce callback irq_chip.irq_write_msi_msg genirq: Work around __irq_set_handler vs stacked domains ordering issues irqdomain: Introduce helper function irq_domain_add_hierarchy() irqdomain: Implement a method to automatically call parent domains alloc/free genirq: Introduce helper irq_domain_set_info() to reduce duplicated code genirq: Split out flow handler typedefs into seperate header file genirq: Add IRQ_SET_MASK_OK_DONE to support stacked irqchip genirq: Introduce irq_chip.irq_compose_msi_msg() to support stacked irqchip genirq: Add more helper functions to support stacked irq_chip genirq: Introduce helper functions to support stacked irq_chip irqdomain: Do irq_find_mapping and set_type for hierarchy irqdomain in case OF ...
Diffstat (limited to 'kernel/irq/msi.c')
-rw-r--r--kernel/irq/msi.c330
1 files changed, 330 insertions, 0 deletions
diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
new file mode 100644
index 000000000000..3e18163f336f
--- /dev/null
+++ b/kernel/irq/msi.c
@@ -0,0 +1,330 @@
+/*
+ * 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/types.h>
+#include <linux/device.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/msi.h>
+
+/* Temparory solution for building, will be removed later */
+#include <linux/pci.h>
+
+void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
+{
+ *msg = entry->msg;
+}
+
+void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg)
+{
+ struct msi_desc *entry = irq_get_msi_desc(irq);
+
+ __get_cached_msi_msg(entry, msg);
+}
+EXPORT_SYMBOL_GPL(get_cached_msi_msg);
+
+#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
+static inline void irq_chip_write_msi_msg(struct irq_data *data,
+ struct msi_msg *msg)
+{
+ data->chip->irq_write_msi_msg(data, msg);
+}
+
+/**
+ * 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,
+};
+
+#ifdef GENERIC_MSI_DOMAIN_OPS
+static irq_hw_number_t msi_domain_ops_get_hwirq(struct msi_domain_info *info,
+ msi_alloc_info_t *arg)
+{
+ return arg->hwirq;
+}
+
+static int msi_domain_ops_prepare(struct irq_domain *domain, struct device *dev,
+ int nvec, msi_alloc_info_t *arg)
+{
+ memset(arg, 0, sizeof(*arg));
+ return 0;
+}
+
+static void msi_domain_ops_set_desc(msi_alloc_info_t *arg,
+ struct msi_desc *desc)
+{
+ arg->desc = desc;
+}
+#else
+#define msi_domain_ops_get_hwirq NULL
+#define msi_domain_ops_prepare NULL
+#define msi_domain_ops_set_desc NULL
+#endif /* !GENERIC_MSI_DOMAIN_OPS */
+
+static int msi_domain_ops_init(struct irq_domain *domain,
+ struct msi_domain_info *info,
+ unsigned int virq, irq_hw_number_t hwirq,
+ msi_alloc_info_t *arg)
+{
+ irq_domain_set_hwirq_and_chip(domain, virq, hwirq, info->chip,
+ info->chip_data);
+ if (info->handler && info->handler_name) {
+ __irq_set_handler(virq, info->handler, 0, info->handler_name);
+ if (info->handler_data)
+ irq_set_handler_data(virq, info->handler_data);
+ }
+ return 0;
+}
+
+static int msi_domain_ops_check(struct irq_domain *domain,
+ struct msi_domain_info *info,
+ struct device *dev)
+{
+ return 0;
+}
+
+static struct msi_domain_ops msi_domain_ops_default = {
+ .get_hwirq = msi_domain_ops_get_hwirq,
+ .msi_init = msi_domain_ops_init,
+ .msi_check = msi_domain_ops_check,
+ .msi_prepare = msi_domain_ops_prepare,
+ .set_desc = msi_domain_ops_set_desc,
+};
+
+static void msi_domain_update_dom_ops(struct msi_domain_info *info)
+{
+ struct msi_domain_ops *ops = info->ops;
+
+ if (ops == NULL) {
+ info->ops = &msi_domain_ops_default;
+ return;
+ }
+
+ if (ops->get_hwirq == NULL)
+ ops->get_hwirq = msi_domain_ops_default.get_hwirq;
+ if (ops->msi_init == NULL)
+ ops->msi_init = msi_domain_ops_default.msi_init;
+ if (ops->msi_check == NULL)
+ ops->msi_check = msi_domain_ops_default.msi_check;
+ if (ops->msi_prepare == NULL)
+ ops->msi_prepare = msi_domain_ops_default.msi_prepare;
+ if (ops->set_desc == NULL)
+ ops->set_desc = msi_domain_ops_default.set_desc;
+}
+
+static void msi_domain_update_chip_ops(struct msi_domain_info *info)
+{
+ struct irq_chip *chip = info->chip;
+
+ BUG_ON(!chip);
+ if (!chip->irq_mask)
+ chip->irq_mask = pci_msi_mask_irq;
+ if (!chip->irq_unmask)
+ chip->irq_unmask = pci_msi_unmask_irq;
+ if (!chip->irq_set_affinity)
+ chip->irq_set_affinity = msi_domain_set_affinity;
+}
+
+/**
+ * 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 *node,
+ struct msi_domain_info *info,
+ struct irq_domain *parent)
+{
+ if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS)
+ msi_domain_update_dom_ops(info);
+ if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
+ msi_domain_update_chip_ops(info);
+
+ return irq_domain_add_hierarchy(parent, 0, 0, node, &msi_domain_ops,
+ info);
+}
+
+/**
+ * msi_domain_alloc_irqs - Allocate interrupts from a MSI interrupt domain
+ * @domain: The domain to allocate from
+ * @dev: Pointer to device struct of the device for which the interrupts
+ * are allocated
+ * @nvec: The number of interrupts to allocate
+ *
+ * Returns 0 on success or an error code.
+ */
+int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
+ int nvec)
+{
+ struct msi_domain_info *info = domain->host_data;
+ struct msi_domain_ops *ops = info->ops;
+ msi_alloc_info_t arg;
+ struct msi_desc *desc;
+ int i, ret, virq = -1;
+
+ ret = ops->msi_check(domain, info, dev);
+ if (ret == 0)
+ ret = ops->msi_prepare(domain, dev, nvec, &arg);
+ if (ret)
+ return ret;
+
+ for_each_msi_entry(desc, dev) {
+ ops->set_desc(&arg, desc);
+ if (info->flags & MSI_FLAG_IDENTITY_MAP)
+ virq = (int)ops->get_hwirq(info, &arg);
+ else
+ virq = -1;
+
+ virq = __irq_domain_alloc_irqs(domain, virq, desc->nvec_used,
+ dev_to_node(dev), &arg, false);
+ if (virq < 0) {
+ ret = -ENOSPC;
+ if (ops->handle_error)
+ ret = ops->handle_error(domain, desc, ret);
+ if (ops->msi_finish)
+ ops->msi_finish(&arg, ret);
+ return ret;
+ }
+
+ for (i = 0; i < desc->nvec_used; i++)
+ irq_set_msi_desc_off(virq, i, desc);
+ }
+
+ if (ops->msi_finish)
+ ops->msi_finish(&arg, 0);
+
+ for_each_msi_entry(desc, dev) {
+ if (desc->nvec_used == 1)
+ dev_dbg(dev, "irq %d for MSI\n", virq);
+ else
+ dev_dbg(dev, "irq [%d-%d] for MSI\n",
+ virq, virq + desc->nvec_used - 1);
+ }
+
+ return 0;
+}
+
+/**
+ * msi_domain_free_irqs - Free interrupts from a MSI interrupt @domain associated tp @dev
+ * @domain: The domain to managing the interrupts
+ * @dev: Pointer to device struct of the device for which the interrupts
+ * are free
+ */
+void msi_domain_free_irqs(struct irq_domain *domain, struct device *dev)
+{
+ struct msi_desc *desc;
+
+ for_each_msi_entry(desc, dev) {
+ irq_domain_free_irqs(desc->irq, desc->nvec_used);
+ desc->irq = 0;
+ }
+}
+
+/**
+ * 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 */