[tip:irq/irqdomain] genirq: Introduce msi_domain_alloc/free_irqs( )

tip-bot for Jiang Liu
2014-11-24T20:21:55Z

Commit-ID: d9109698be6e7439e6082aa00d79d4556114739b
Gitweb: http://git.kernel.org/tip/d9109698be6e7439e6082aa00d79d4556114739b
Author: Jiang Liu <jiang.liu@linux.intel.com>
AuthorDate: Sat, 15 Nov 2014 22:24:04 +0800
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitDate: Sun, 23 Nov 2014 13:01:47 +0100

genirq: Introduce msi_domain_alloc/free_irqs()

Introduce msi_domain_{alloc|free}_irqs() to alloc/free interrupts
from generic MSI irqdomain.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Alexander Gordeev <agordeev@redhat.com>
Link: http://lkml.kernel.org/r/1416061447-9472-7-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
include/linux/msi.h | 29 +++++++++++++++++++++
kernel/irq/msi.c | 75 +++++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 104 insertions(+)

diff --git a/include/linux/msi.h b/include/linux/msi.h
index b5ca245..7a93a98 100644
--- a/include/linux/msi.h
+++ b/include/linux/msi.h
@@ -115,6 +115,9 @@ struct msi_controller {
};

#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
+
+#include <asm/msi.h>
+
struct irq_domain;
struct irq_chip;
struct device_node;
@@ -125,6 +128,18 @@ struct msi_domain_info;
* @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
+ * @msi_check: Callback for verification of the domain/info/dev data
+ * @msi_prepare: Prepare the allocation of the interrupts in the domain
+ * @msi_finish: Optional callbacl to finalize the allocation
+ * @set_desc: Set the msi descriptor for an interrupt
+ * @handle_error: Optional error handler if the allocation fails
+ *
+ * @get_hwirq, @msi_init and @msi_free are callbacks used by
+ * msi_create_irq_domain() and related interfaces
+ *
+ * @msi_check, @msi_prepare, @msi_finish, @set_desc and @handle_error
+ * are callbacks used by msi_irq_domain_alloc_irqs() and related
+ * interfaces which are based on msi_desc.
*/
struct msi_domain_ops {
irq_hw_number_t (*get_hwirq)(struct msi_domain_info *info, void *arg);
@@ -135,6 +150,17 @@ struct msi_domain_ops {
void (*msi_free)(struct irq_domain *domain,
struct msi_domain_info *info,
unsigned int virq);
+ int (*msi_check)(struct irq_domain *domain,
+ struct msi_domain_info *info,
+ struct device *dev);
+ int (*msi_prepare)(struct irq_domain *domain,
+ struct device *dev, int nvec,
+ msi_alloc_info_t *arg);
+ void (*msi_finish)(msi_alloc_info_t *arg, int retval);
+ void (*set_desc)(msi_alloc_info_t *arg,
+ struct msi_desc *desc);
+ int (*handle_error)(struct irq_domain *domain,
+ struct msi_desc *desc, int error);
};

/**
@@ -155,6 +181,9 @@ int msi_domain_set_affinity(struct irq_data *data, const struct cpumask *mask,
struct irq_domain *msi_create_irq_domain(struct device_node *of_node,
struct msi_domain_info *info,
struct irq_domain *parent);
+int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
+ int nvec);
+void msi_domain_free_irqs(struct irq_domain *domain, struct device *dev);
struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain);

#endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */
diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
index 5e0cef4..23111aa 100644
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -13,6 +13,9 @@
#include <linux/irqdomain.h>
#include <linux/msi.h>

+/* Temparory solution for building, will be removed later */
+#include <linux/pci.h>
+
#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
/**
* msi_domain_set_affinity - Generic affinity setter function for MSI domains
@@ -127,6 +130,78 @@ struct irq_domain *msi_create_irq_domain(struct device_node *of_node,
}

/**
+ * 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);
+
+ virq = __irq_domain_alloc_irqs(domain, -1, 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
*