Merge branch 'pci/msi' into next

* pci/msi:
  PCI/MSI: Remove unnecessary temporary variable
  PCI/MSI: Use __write_msi_msg() instead of write_msi_msg()
  MSI/powerpc: Use __read_msi_msg() instead of read_msi_msg()
  PCI/MSI: Use __get_cached_msi_msg() instead of get_cached_msi_msg()
  PCI/MSI: Add "msi_bus" sysfs MSI/MSI-X control for endpoints
  PCI/MSI: Remove "pos" from the struct msi_desc msi_attrib
  PCI/MSI: Remove unused kobject from struct msi_desc
  PCI/MSI: Rename pci_msi_check_device() to pci_msi_supported()
  PCI/MSI: Move D0 check into pci_msi_check_device()
  PCI/MSI: Remove arch_msi_check_device()
  irqchip: armada-370-xp: Remove arch_msi_check_device()
  PCI/MSI/PPC: Remove arch_msi_check_device()

Conflicts:
	drivers/pci/host/pcie-designware.c

3 files changed, 39 insertions, 80 deletions

diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
index 34e736601259..f72744599d12 100644
--- a/drivers/pci/host/pcie-designware.c
+++ b/drivers/pci/host/pcie-designware.c
@@ -343,9 +343,8 @@ static int dw_msi_setup_irq(struct msi_chip *chip, struct pci_dev *pdev,
 	struct msi_msg msg;
 	struct pcie_port *pp = sys_to_pcie(pdev->bus->sysdata);
 
-	pci_read_config_word(pdev, desc->msi_attrib.pos+PCI_MSI_FLAGS,
-				&msg_ctr);
-	msgvec = (msg_ctr&PCI_MSI_FLAGS_QSIZE) >> 4;
+	pci_read_config_word(pdev, pdev->msi_cap + PCI_MSI_FLAGS, &msg_ctr);
+	msgvec = (msg_ctr & PCI_MSI_FLAGS_QSIZE) >> 4;
 	if (msgvec == 0)
 		msgvec = (msg_ctr & PCI_MSI_FLAGS_QMASK) >> 1;
 	if (msgvec > 5)
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 5a40516444f3..2f7c92c4757a 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -56,16 +56,6 @@ void __weak arch_teardown_msi_irq(unsigned int irq)
 	chip->teardown_irq(chip, irq);
 }
 
-int __weak arch_msi_check_device(struct pci_dev *dev, int nvec, int type)
-{
-	struct msi_chip *chip = dev->bus->msi;
-
-	if (!chip || !chip->check_device)
-		return 0;
-
-	return chip->check_device(chip, dev, nvec, type);
-}
-
 int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 {
 	struct msi_desc *entry;
@@ -130,7 +120,7 @@ static void default_restore_msi_irq(struct pci_dev *dev, int irq)
 	}
 
 	if (entry)
-		write_msi_msg(irq, &entry->msg);
+		__write_msi_msg(entry, &entry->msg);
 }
 
 void __weak arch_restore_msi_irqs(struct pci_dev *dev)
@@ -384,17 +374,6 @@ static void free_msi_irqs(struct pci_dev *dev)
 				iounmap(entry->mask_base);
 		}
 
-		/*
-		 * Its possible that we get into this path
-		 * When populate_msi_sysfs fails, which means the entries
-		 * were not registered with sysfs.  In that case don't
-		 * unregister them.
-		 */
-		if (entry->kobj.parent) {
-			kobject_del(&entry->kobj);
-			kobject_put(&entry->kobj);
-		}
-
 		list_del(&entry->list);
 		kfree(entry);
 	}
@@ -595,7 +574,6 @@ static struct msi_desc *msi_setup_entry(struct pci_dev *dev)
 	entry->msi_attrib.entry_nr	= 0;
 	entry->msi_attrib.maskbit	= !!(control & PCI_MSI_FLAGS_MASKBIT);
 	entry->msi_attrib.default_irq	= dev->irq;	/* Save IOAPIC IRQ */
-	entry->msi_attrib.pos		= dev->msi_cap;
 	entry->msi_attrib.multi_cap	= (control & PCI_MSI_FLAGS_QMASK) >> 1;
 
 	if (control & PCI_MSI_FLAGS_64BIT)
@@ -699,7 +677,6 @@ static int msix_setup_entries(struct pci_dev *dev, void __iomem *base,
 		entry->msi_attrib.is_64		= 1;
 		entry->msi_attrib.entry_nr	= entries[i].entry;
 		entry->msi_attrib.default_irq	= dev->irq;
-		entry->msi_attrib.pos		= dev->msix_cap;
 		entry->mask_base		= base;
 
 		list_add_tail(&entry->list, &dev->msi_list);
@@ -806,23 +783,24 @@ out_free:
 }
 
 /**
- * pci_msi_check_device - check whether MSI may be enabled on a device
+ * pci_msi_supported - check whether MSI may be enabled on a device
  * @dev: pointer to the pci_dev data structure of MSI device function
  * @nvec: how many MSIs have been requested ?
- * @type: are we checking for MSI or MSI-X ?
  *
  * Look at global flags, the device itself, and its parent buses
  * to determine if MSI/-X are supported for the device. If MSI/-X is
- * supported return 0, else return an error code.
+ * supported return 1, else return 0.
  **/
-static int pci_msi_check_device(struct pci_dev *dev, int nvec, int type)
+static int pci_msi_supported(struct pci_dev *dev, int nvec)
 {
 	struct pci_bus *bus;
-	int ret;
 
 	/* MSI must be globally enabled and supported by the device */
-	if (!pci_msi_enable || !dev || dev->no_msi)
-		return -EINVAL;
+	if (!pci_msi_enable)
+		return 0;
+
+	if (!dev || dev->no_msi || dev->current_state != PCI_D0)
+		return 0;
 
 	/*
 	 * You can't ask to have 0 or less MSIs configured.
@@ -830,7 +808,7 @@ static int pci_msi_check_device(struct pci_dev *dev, int nvec, int type)
 	 *  b) the list manipulation code assumes nvec >= 1.
 	 */
 	if (nvec < 1)
-		return -ERANGE;
+		return 0;
 
 	/*
 	 * Any bridge which does NOT route MSI transactions from its
@@ -841,13 +819,9 @@ static int pci_msi_check_device(struct pci_dev *dev, int nvec, int type)
 	 */
 	for (bus = dev->bus; bus; bus = bus->parent)
 		if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI)
-			return -EINVAL;
-
-	ret = arch_msi_check_device(dev, nvec, type);
-	if (ret)
-		return ret;
+			return 0;
 
-	return 0;
+	return 1;
 }
 
 /**
@@ -946,15 +920,14 @@ EXPORT_SYMBOL(pci_msix_vec_count);
  **/
 int pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, int nvec)
 {
-	int status, nr_entries;
+	int nr_entries;
 	int i, j;
 
-	if (!entries || !dev->msix_cap || dev->current_state != PCI_D0)
+	if (!pci_msi_supported(dev, nvec))
 		return -EINVAL;
 
-	status = pci_msi_check_device(dev, nvec, PCI_CAP_ID_MSIX);
-	if (status)
-		return status;
+	if (!entries)
+		return -EINVAL;
 
 	nr_entries = pci_msix_vec_count(dev);
 	if (nr_entries < 0)
@@ -978,8 +951,7 @@ int pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, int nvec)
 		dev_info(&dev->dev, "can't enable MSI-X (MSI IRQ already assigned)\n");
 		return -EINVAL;
 	}
-	status = msix_capability_init(dev, entries, nvec);
-	return status;
+	return msix_capability_init(dev, entries, nvec);
 }
 EXPORT_SYMBOL(pci_enable_msix);
 
@@ -1062,7 +1034,7 @@ int pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec)
 	int nvec;
 	int rc;
 
-	if (dev->current_state != PCI_D0)
+	if (!pci_msi_supported(dev, minvec))
 		return -EINVAL;
 
 	WARN_ON(!!dev->msi_enabled);
@@ -1086,17 +1058,6 @@ int pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec)
 		nvec = maxvec;
 
 	do {
-		rc = pci_msi_check_device(dev, nvec, PCI_CAP_ID_MSI);
-		if (rc < 0) {
-			return rc;
-		} else if (rc > 0) {
-			if (rc < minvec)
-				return -ENOSPC;
-			nvec = rc;
-		}
-	} while (rc);
-
-	do {
 		rc = msi_capability_init(dev, nvec);
 		if (rc < 0) {
 			return rc;
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 76ef7914c9aa..92b6d9ab00e4 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -250,46 +250,45 @@ static ssize_t msi_bus_show(struct device *dev, struct device_attribute *attr,
 			    char *buf)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
+	struct pci_bus *subordinate = pdev->subordinate;
 
-	if (!pdev->subordinate)
-		return 0;
-
-	return sprintf(buf, "%u\n",
-		       !(pdev->subordinate->bus_flags & PCI_BUS_FLAGS_NO_MSI));
+	return sprintf(buf, "%u\n", subordinate ?
+		       !(subordinate->bus_flags & PCI_BUS_FLAGS_NO_MSI)
+			   : !pdev->no_msi);
 }
 
 static ssize_t msi_bus_store(struct device *dev, struct device_attribute *attr,
 			     const char *buf, size_t count)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
+	struct pci_bus *subordinate = pdev->subordinate;
 	unsigned long val;
 
 	if (kstrtoul(buf, 0, &val) < 0)
 		return -EINVAL;
 
-	/*
-	 * Bad things may happen if the no_msi flag is changed
-	 * while drivers are loaded.
-	 */
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
 
 	/*
-	 * Maybe devices without subordinate buses shouldn't have this
-	 * attribute in the first place?
+	 * "no_msi" and "bus_flags" only affect what happens when a driver
+	 * requests MSI or MSI-X.  They don't affect any drivers that have
+	 * already requested MSI or MSI-X.
 	 */
-	if (!pdev->subordinate)
+	if (!subordinate) {
+		pdev->no_msi = !val;
+		dev_info(&pdev->dev, "MSI/MSI-X %s for future drivers\n",
+			 val ? "allowed" : "disallowed");
 		return count;
-
-	/* Is the flag going to change, or keep the value it already had? */
-	if (!(pdev->subordinate->bus_flags & PCI_BUS_FLAGS_NO_MSI) ^
-	    !!val) {
-		pdev->subordinate->bus_flags ^= PCI_BUS_FLAGS_NO_MSI;
-
-		dev_warn(&pdev->dev, "forced subordinate bus to%s support MSI, bad things could happen\n",
-			 val ? "" : " not");
 	}
 
+	if (val)
+		subordinate->bus_flags &= ~PCI_BUS_FLAGS_NO_MSI;
+	else
+		subordinate->bus_flags |= PCI_BUS_FLAGS_NO_MSI;
+
+	dev_info(&subordinate->dev, "MSI/MSI-X %s for future drivers of devices on this bus\n",
+		 val ? "allowed" : "disallowed");
 	return count;
 }
 static DEVICE_ATTR_RW(msi_bus);