irqchip/gicv3-its: Split PCI/MSI code from the core ITS driver

It is becoming obvious that having the PCI/MSI code in the same
file as the the core ITS code is giving people implementing non-PCI
MSI support the wrong kind of idea.

In order to make things a bit clearer, let's move the PCI/MSI code
out to its own file. Hopefully it will make it clear that whoever
thinks of hooking into the core ITS better have a very strong point.

We use a temporary entry point that will get removed in a subsequent
patch, once the proper infrastructure is added.

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/1438091186-10244-12-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 11 insertions, 83 deletions

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 1df956afb937..7f995d876029 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -642,26 +642,6 @@ static struct irq_chip its_irq_chip = {
 	.irq_compose_msi_msg	= its_irq_compose_msi_msg,
 };
 
-static void its_mask_msi_irq(struct irq_data *d)
-{
-	pci_msi_mask_irq(d);
-	irq_chip_mask_parent(d);
-}
-
-static void its_unmask_msi_irq(struct irq_data *d)
-{
-	pci_msi_unmask_irq(d);
-	irq_chip_unmask_parent(d);
-}
-
-static struct irq_chip its_msi_irq_chip = {
-	.name			= "ITS-MSI",
-	.irq_unmask		= its_unmask_msi_irq,
-	.irq_mask		= its_mask_msi_irq,
-	.irq_eoi		= irq_chip_eoi_parent,
-	.irq_write_msi_msg	= pci_msi_domain_write_msg,
-};
-
 /*
  * How we allocate LPIs:
  *
@@ -1208,85 +1188,34 @@ static int its_alloc_device_irq(struct its_device *dev, irq_hw_number_t *hwirq)
 	return 0;
 }
 
-struct its_pci_alias {
-	struct pci_dev	*pdev;
-	u32		dev_id;
-	u32		count;
-};
-
-static int its_pci_msi_vec_count(struct pci_dev *pdev)
-{
-	int msi, msix;
-
-	msi = max(pci_msi_vec_count(pdev), 0);
-	msix = max(pci_msix_vec_count(pdev), 0);
-
-	return max(msi, msix);
-}
-
-static int its_get_pci_alias(struct pci_dev *pdev, u16 alias, void *data)
+int its_msi_prepare(struct irq_domain *domain, u32 dev_id,
+		    int nvec, msi_alloc_info_t *info)
 {
-	struct its_pci_alias *dev_alias = data;
-
-	dev_alias->dev_id = alias;
-	if (pdev != dev_alias->pdev)
-		dev_alias->count += its_pci_msi_vec_count(dev_alias->pdev);
-
-	return 0;
-}
-
-static int its_msi_prepare(struct irq_domain *domain, struct device *dev,
-			   int nvec, msi_alloc_info_t *info)
-{
-	struct pci_dev *pdev;
 	struct its_node *its;
 	struct its_device *its_dev;
-	struct its_pci_alias dev_alias;
-
-	if (!dev_is_pci(dev))
-		return -EINVAL;
-
-	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);
 	its = domain->parent->host_data;
-
-	its_dev = its_find_device(its, dev_alias.dev_id);
+	its_dev = its_find_device(its, dev_id);
 	if (its_dev) {
 		/*
 		 * We already have seen this ID, probably through
 		 * another alias (PCI bridge of some sort). No need to
 		 * create the device.
 		 */
-		dev_dbg(dev, "Reusing ITT for devID %x\n", dev_alias.dev_id);
+		pr_debug("Reusing ITT for devID %x\n", dev_id);
 		goto out;
 	}
 
-	its_dev = its_create_device(its, dev_alias.dev_id, dev_alias.count);
+	its_dev = its_create_device(its, dev_id, nvec);
 	if (!its_dev)
 		return -ENOMEM;
 
-	dev_dbg(&pdev->dev, "ITT %d entries, %d bits\n",
-		dev_alias.count, ilog2(dev_alias.count));
+	pr_debug("ITT %d entries, %d bits\n", nvec, ilog2(nvec));
 out:
 	info->scratchpad[0].ptr = its_dev;
-	info->scratchpad[1].ptr = dev;
 	return 0;
 }
 
-static struct msi_domain_ops its_pci_msi_ops = {
-	.msi_prepare	= its_msi_prepare,
-};
-
-static struct msi_domain_info its_pci_msi_domain_info = {
-	.flags	= (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-		   MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX),
-	.ops	= &its_pci_msi_ops,
-	.chip	= &its_msi_irq_chip,
-};
-
 static int its_irq_gic_domain_alloc(struct irq_domain *domain,
 				    unsigned int virq,
 				    irq_hw_number_t hwirq)
@@ -1322,9 +1251,9 @@ static int its_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
 
 		irq_domain_set_hwirq_and_chip(domain, virq + i,
 					      hwirq, &its_irq_chip, its_dev);
-		dev_dbg(info->scratchpad[1].ptr, "ID:%d pID:%d vID:%d\n",
-			(int)(hwirq - its_dev->event_map.lpi_base),
-			(int)hwirq, virq + i);
+		pr_debug("ID:%d pID:%d vID:%d\n",
+			 (int)(hwirq - its_dev->event_map.lpi_base),
+			 (int) hwirq, virq + i);
 	}
 
 	return 0;
@@ -1523,9 +1452,8 @@ static int its_probe(struct device_node *node, struct irq_domain *parent)
 
 		its->domain->parent = parent;
 
-		its->msi_chip.domain = pci_msi_create_irq_domain(node,
-								 &its_pci_msi_domain_info,
-								 its->domain);
+		its->msi_chip.domain = its_pci_msi_alloc_domain(node,
+								its->domain);
 		if (!its->msi_chip.domain) {
 			err = -ENOMEM;
 			goto out_free_domains;