irqchip/gicv3-its: Make the PCI/MSI code standalone

We can now lookup the base ITS domain, making it possible to
initialize the PCI/MSI code independently from the main ITS
subsystem.

This allows us to remove all the previously add hooks.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: Yijing Wang <wangyijing@huawei.com>
Cc: Ma Jun <majun258@huawei.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Duc Dang <dhdang@apm.com>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1438091186-10244-15-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/drivers/irqchip/irq-gic-v3-its-pci-msi.c b/drivers/irqchip/irq-gic-v3-its-pci-msi.c
index 76147219da7f4a1a9386f184683dfd651e6117d0..cf351c6374645e7b0e4fe982a937d49b4904cfe9 100644 (file)
--- a/drivers/irqchip/irq-gic-v3-its-pci-msi.c
+++ b/drivers/irqchip/irq-gic-v3-its-pci-msi.c
@@ -20,8 +20,6 @@
 #include <linux/of_irq.h>
 #include <linux/of_pci.h>
 
-#include <linux/irqchip/arm-gic-v3.h>
-
 static void its_mask_msi_irq(struct irq_data *d)
 {
        pci_msi_mask_irq(d);
@@ -74,17 +72,24 @@ static int its_pci_msi_prepare(struct irq_domain *domain, struct device *dev,
 {
        struct pci_dev *pdev;
        struct its_pci_alias dev_alias;
+       struct msi_domain_info *msi_info;
 
        if (!dev_is_pci(dev))
                return -EINVAL;
 
+       msi_info = msi_get_domain_info(domain->parent);
+
        pdev = to_pci_dev(dev);
        dev_alias.pdev = pdev;
        dev_alias.count = nvec;
 
        pci_for_each_dma_alias(pdev, its_get_pci_alias, &dev_alias);
 
-       return its_msi_prepare(domain, dev_alias.dev_id, dev_alias.count, info);
+       /* ITS specific DeviceID, as the core ITS ignores dev. */
+       info->scratchpad[0].ul = dev_alias.dev_id;
+
+       return msi_info->ops->msi_prepare(domain->parent,
+                                         dev, dev_alias.count, info);
 }
 
 static struct msi_domain_ops its_pci_msi_ops = {
@@ -98,8 +103,38 @@ static struct msi_domain_info its_pci_msi_domain_info = {
        .chip   = &its_msi_irq_chip,
 };
 
-struct irq_domain *its_pci_msi_alloc_domain(struct device_node *np,
-                                           struct irq_domain *parent)
+static struct of_device_id its_device_id[] = {
+       {       .compatible     = "arm,gic-v3-its",     },
+       {},
+};
+
+static int __init its_pci_msi_init(void)
 {
-       return pci_msi_create_irq_domain(np, &its_pci_msi_domain_info, parent);
+       struct device_node *np;
+       struct irq_domain *parent;
+
+       for (np = of_find_matching_node(NULL, its_device_id); np;
+            np = of_find_matching_node(np, its_device_id)) {
+               if (!of_property_read_bool(np, "msi-controller"))
+                       continue;
+
+               parent = irq_find_matching_host(np, DOMAIN_BUS_NEXUS);
+               if (!parent || !msi_get_domain_info(parent)) {
+                       pr_err("%s: unable to locate ITS domain\n",
+                              np->full_name);
+                       continue;
+               }
+
+               if (!pci_msi_create_irq_domain(np, &its_pci_msi_domain_info,
+                                              parent)) {
+                       pr_err("%s: unable to create PCI domain\n",
+                              np->full_name);
+                       continue;
+               }
+
+               pr_info("PCI/MSI: %s domain created\n", np->full_name);
+       }
+
+       return 0;
 }
+early_initcall(its_pci_msi_init);

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index dc4fbbfa0212d121b1afeaa419212d20094142a8..26b55c53755f0db82c5b4cbcd1c16a9beb5c5109 100644 (file)
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -59,7 +59,6 @@ struct its_collection {
 struct its_node {
        raw_spinlock_t          lock;
        struct list_head        entry;
-       struct irq_domain       *domain;
        void __iomem            *base;
        unsigned long           phys_base;
        struct its_cmd_block    *cmd_base;
@@ -1187,13 +1186,25 @@ static int its_alloc_device_irq(struct its_device *dev, irq_hw_number_t *hwirq)
        return 0;
 }
 
-int its_msi_prepare(struct irq_domain *domain, u32 dev_id,
-                   int nvec, msi_alloc_info_t *info)
+static int its_msi_prepare(struct irq_domain *domain, struct device *dev,
+                          int nvec, msi_alloc_info_t *info)
 {
        struct its_node *its;
        struct its_device *its_dev;
+       struct msi_domain_info *msi_info;
+       u32 dev_id;
+
+       /*
+        * We ignore "dev" entierely, and rely on the dev_id that has
+        * been passed via the scratchpad. This limits this domain's
+        * usefulness to upper layers that definitely know that they
+        * are built on top of the ITS.
+        */
+       dev_id = info->scratchpad[0].ul;
+
+       msi_info = msi_get_domain_info(domain);
+       its = msi_info->data;
 
-       its = domain->parent->host_data;
        its_dev = its_find_device(its, dev_id);
        if (its_dev) {
                /*
@@ -1215,6 +1226,10 @@ out:
        return 0;
 }
 
+static struct msi_domain_ops its_msi_domain_ops = {
+       .msi_prepare    = its_msi_prepare,
+};
+
 static int its_irq_gic_domain_alloc(struct irq_domain *domain,
                                    unsigned int virq,
                                    irq_hw_number_t hwirq)
@@ -1353,7 +1368,7 @@ static int its_probe(struct device_node *node, struct irq_domain *parent)
        struct resource res;
        struct its_node *its;
        void __iomem *its_base;
-       struct irq_domain *inner_domain = NULL;
+       struct irq_domain *inner_domain;
        u32 val;
        u64 baser, tmp;
        int err;
@@ -1443,20 +1458,26 @@ static int its_probe(struct device_node *node, struct irq_domain *parent)
        writel_relaxed(GITS_CTLR_ENABLE, its->base + GITS_CTLR);
 
        if (of_property_read_bool(node, "msi-controller")) {
+               struct msi_domain_info *info;
+
+               info = kzalloc(sizeof(*info), GFP_KERNEL);
+               if (!info) {
+                       err = -ENOMEM;
+                       goto out_free_tables;
+               }
+
                inner_domain = irq_domain_add_tree(node, &its_domain_ops, its);
                if (!inner_domain) {
                        err = -ENOMEM;
+                       kfree(info);
                        goto out_free_tables;
                }
 
                inner_domain->parent = parent;
                inner_domain->bus_token = DOMAIN_BUS_NEXUS;
-
-               its->domain = its_pci_msi_alloc_domain(node, inner_domain);
-               if (!its->domain) {
-                       err = -ENOMEM;
-                       goto out_free_domains;
-               }
+               info->ops = &its_msi_domain_ops;
+               info->data = its;
+               inner_domain->host_data = info;
        }
 
        spin_lock(&its_lock);
@@ -1465,11 +1486,6 @@ static int its_probe(struct device_node *node, struct irq_domain *parent)
 
        return 0;
 
-out_free_domains:
-       if (its->domain)
-               irq_domain_remove(its->domain);
-       if (inner_domain)
-               irq_domain_remove(inner_domain);
 out_free_tables:
        its_free_tables(its);
 out_free_cmd:

diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h
index d6149baaf643849eda1451e68e03faee87559b93..bf982e021fbd043f8fddf0903a6926f3558a679b 100644 (file)
--- a/include/linux/irqchip/arm-gic-v3.h
+++ b/include/linux/irqchip/arm-gic-v3.h
@@ -389,11 +389,6 @@ struct irq_domain;
 int its_cpu_init(void);
 int its_init(struct device_node *node, struct rdists *rdists,
             struct irq_domain *domain);
-int its_msi_prepare(struct irq_domain *domain, u32 dev_id,
-                   int nvec, msi_alloc_info_t *info);
-
-struct irq_domain *its_pci_msi_alloc_domain(struct device_node *node,
-                                           struct irq_domain *parent);
 
 #endif