1 files changed, 339 insertions, 135 deletions

diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 084587d7cd13..1c7f6a8e69d1 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -19,19 +19,81 @@
 #include <linux/errno.h>
 #include <linux/io.h>
 #include <linux/slab.h>
+#include <linux/irqdomain.h>
 
 #include "pci.h"
 
 static int pci_msi_enable = 1;
+int pci_msi_ignore_mask;
 
 #define msix_table_size(flags)	((flags & PCI_MSIX_FLAGS_QSIZE) + 1)
 
+#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
+static struct irq_domain *pci_msi_default_domain;
+static DEFINE_MUTEX(pci_msi_domain_lock);
+
+struct irq_domain * __weak arch_get_pci_msi_domain(struct pci_dev *dev)
+{
+	return pci_msi_default_domain;
+}
+
+static struct irq_domain *pci_msi_get_domain(struct pci_dev *dev)
+{
+	struct irq_domain *domain;
+
+	domain = dev_get_msi_domain(&dev->dev);
+	if (domain)
+		return domain;
+
+	return arch_get_pci_msi_domain(dev);
+}
+
+static int pci_msi_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+{
+	struct irq_domain *domain;
+
+	domain = pci_msi_get_domain(dev);
+	if (domain)
+		return pci_msi_domain_alloc_irqs(domain, dev, nvec, type);
+
+	return arch_setup_msi_irqs(dev, nvec, type);
+}
+
+static void pci_msi_teardown_msi_irqs(struct pci_dev *dev)
+{
+	struct irq_domain *domain;
+
+	domain = pci_msi_get_domain(dev);
+	if (domain)
+		pci_msi_domain_free_irqs(domain, dev);
+	else
+		arch_teardown_msi_irqs(dev);
+}
+#else
+#define pci_msi_setup_msi_irqs		arch_setup_msi_irqs
+#define pci_msi_teardown_msi_irqs	arch_teardown_msi_irqs
+#endif
 
 /* Arch hooks */
 
+struct msi_controller * __weak pcibios_msi_controller(struct pci_dev *dev)
+{
+	return NULL;
+}
+
+static struct msi_controller *pci_msi_controller(struct pci_dev *dev)
+{
+	struct msi_controller *msi_ctrl = dev->bus->msi;
+
+	if (msi_ctrl)
+		return msi_ctrl;
+
+	return pcibios_msi_controller(dev);
+}
+
 int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
 {
-	struct msi_chip *chip = dev->bus->msi;
+	struct msi_controller *chip = pci_msi_controller(dev);
 	int err;
 
 	if (!chip || !chip->setup_irq)
@@ -48,7 +110,7 @@ int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
 
 void __weak arch_teardown_msi_irq(unsigned int irq)
 {
-	struct msi_chip *chip = irq_get_chip_data(irq);
+	struct msi_controller *chip = irq_get_chip_data(irq);
 
 	if (!chip || !chip->teardown_irq)
 		return;
@@ -85,19 +147,13 @@ int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
  */
 void default_teardown_msi_irqs(struct pci_dev *dev)
 {
+	int i;
 	struct msi_desc *entry;
 
-	list_for_each_entry(entry, &dev->msi_list, list) {
-		int i, nvec;
-		if (entry->irq == 0)
-			continue;
-		if (entry->nvec_used)
-			nvec = entry->nvec_used;
-		else
-			nvec = 1 << entry->msi_attrib.multiple;
-		for (i = 0; i < nvec; i++)
-			arch_teardown_msi_irq(entry->irq + i);
-	}
+	list_for_each_entry(entry, &dev->msi_list, list)
+		if (entry->irq)
+			for (i = 0; i < entry->nvec_used; i++)
+				arch_teardown_msi_irq(entry->irq + i);
 }
 
 void __weak arch_teardown_msi_irqs(struct pci_dev *dev)
@@ -120,7 +176,7 @@ static void default_restore_msi_irq(struct pci_dev *dev, int irq)
 	}
 
 	if (entry)
-		__write_msi_msg(entry, &entry->msg);
+		__pci_write_msi_msg(entry, &entry->msg);
 }
 
 void __weak arch_restore_msi_irqs(struct pci_dev *dev)
@@ -128,27 +184,6 @@ void __weak arch_restore_msi_irqs(struct pci_dev *dev)
 	return default_restore_msi_irqs(dev);
 }
 
-static void msi_set_enable(struct pci_dev *dev, int enable)
-{
-	u16 control;
-
-	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
-	control &= ~PCI_MSI_FLAGS_ENABLE;
-	if (enable)
-		control |= PCI_MSI_FLAGS_ENABLE;
-	pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control);
-}
-
-static void msix_clear_and_set_ctrl(struct pci_dev *dev, u16 clear, u16 set)
-{
-	u16 ctrl;
-
-	pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &ctrl);
-	ctrl &= ~clear;
-	ctrl |= set;
-	pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, ctrl);
-}
-
 static inline __attribute_const__ u32 msi_mask(unsigned x)
 {
 	/* Don't shift by >= width of type */
@@ -163,28 +198,24 @@ static inline __attribute_const__ u32 msi_mask(unsigned x)
  * reliably as devices without an INTx disable bit will then generate a
  * level IRQ which will never be cleared.
  */
-u32 default_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
+u32 __pci_msi_desc_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
 {
 	u32 mask_bits = desc->masked;
 
-	if (!desc->msi_attrib.maskbit)
+	if (pci_msi_ignore_mask || !desc->msi_attrib.maskbit)
 		return 0;
 
 	mask_bits &= ~mask;
 	mask_bits |= flag;
-	pci_write_config_dword(desc->dev, desc->mask_pos, mask_bits);
+	pci_write_config_dword(msi_desc_to_pci_dev(desc), desc->mask_pos,
+			       mask_bits);
 
 	return mask_bits;
 }
 
-__weak u32 arch_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
-{
-	return default_msi_mask_irq(desc, mask, flag);
-}
-
 static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
 {
-	desc->masked = arch_msi_mask_irq(desc, mask, flag);
+	desc->masked = __pci_msi_desc_mask_irq(desc, mask, flag);
 }
 
 /*
@@ -194,11 +225,15 @@ static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
  * file.  This saves a few milliseconds when initialising devices with lots
  * of MSI-X interrupts.
  */
-u32 default_msix_mask_irq(struct msi_desc *desc, u32 flag)
+u32 __pci_msix_desc_mask_irq(struct msi_desc *desc, u32 flag)
 {
 	u32 mask_bits = desc->masked;
 	unsigned offset = desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
 						PCI_MSIX_ENTRY_VECTOR_CTRL;
+
+	if (pci_msi_ignore_mask)
+		return 0;
+
 	mask_bits &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT;
 	if (flag)
 		mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT;
@@ -207,19 +242,14 @@ u32 default_msix_mask_irq(struct msi_desc *desc, u32 flag)
 	return mask_bits;
 }
 
-__weak u32 arch_msix_mask_irq(struct msi_desc *desc, u32 flag)
-{
-	return default_msix_mask_irq(desc, flag);
-}
-
 static void msix_mask_irq(struct msi_desc *desc, u32 flag)
 {
-	desc->masked = arch_msix_mask_irq(desc, flag);
+	desc->masked = __pci_msix_desc_mask_irq(desc, flag);
 }
 
 static void msi_set_mask_bit(struct irq_data *data, u32 flag)
 {
-	struct msi_desc *desc = irq_data_get_msi(data);
+	struct msi_desc *desc = irq_data_get_msi_desc(data);
 
 	if (desc->msi_attrib.is_msix) {
 		msix_mask_irq(desc, flag);
@@ -230,12 +260,20 @@ static void msi_set_mask_bit(struct irq_data *data, u32 flag)
 	}
 }
 
-void mask_msi_irq(struct irq_data *data)
+/**
+ * pci_msi_mask_irq - Generic irq chip callback to mask PCI/MSI interrupts
+ * @data:	pointer to irqdata associated to that interrupt
+ */
+void pci_msi_mask_irq(struct irq_data *data)
 {
 	msi_set_mask_bit(data, 1);
 }
 
-void unmask_msi_irq(struct irq_data *data)
+/**
+ * pci_msi_unmask_irq - Generic irq chip callback to unmask PCI/MSI interrupts
+ * @data:	pointer to irqdata associated to that interrupt
+ */
+void pci_msi_unmask_irq(struct irq_data *data)
 {
 	msi_set_mask_bit(data, 0);
 }
@@ -244,14 +282,15 @@ void default_restore_msi_irqs(struct pci_dev *dev)
 {
 	struct msi_desc *entry;
 
-	list_for_each_entry(entry, &dev->msi_list, list) {
+	list_for_each_entry(entry, &dev->msi_list, list)
 		default_restore_msi_irq(dev, entry->irq);
-	}
 }
 
-void __read_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
+void __pci_read_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 {
-	BUG_ON(entry->dev->current_state != PCI_D0);
+	struct pci_dev *dev = msi_desc_to_pci_dev(entry);
+
+	BUG_ON(dev->current_state != PCI_D0);
 
 	if (entry->msi_attrib.is_msix) {
 		void __iomem *base = entry->mask_base +
@@ -261,7 +300,6 @@ void __read_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 		msg->address_hi = readl(base + PCI_MSIX_ENTRY_UPPER_ADDR);
 		msg->data = readl(base + PCI_MSIX_ENTRY_DATA);
 	} else {
-		struct pci_dev *dev = entry->dev;
 		int pos = dev->msi_cap;
 		u16 data;
 
@@ -279,34 +317,11 @@ void __read_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 	}
 }
 
-void read_msi_msg(unsigned int irq, struct msi_msg *msg)
-{
-	struct msi_desc *entry = irq_get_msi_desc(irq);
-
-	__read_msi_msg(entry, msg);
-}
-
-void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
+void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 {
-	/* Assert that the cache is valid, assuming that
-	 * valid messages are not all-zeroes. */
-	BUG_ON(!(entry->msg.address_hi | entry->msg.address_lo |
-		 entry->msg.data));
+	struct pci_dev *dev = msi_desc_to_pci_dev(entry);
 
-	*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);
-
-void __write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
-{
-	if (entry->dev->current_state != PCI_D0) {
+	if (dev->current_state != PCI_D0) {
 		/* Don't touch the hardware now */
 	} else if (entry->msi_attrib.is_msix) {
 		void __iomem *base;
@@ -317,7 +332,6 @@ void __write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 		writel(msg->address_hi, base + PCI_MSIX_ENTRY_UPPER_ADDR);
 		writel(msg->data, base + PCI_MSIX_ENTRY_DATA);
 	} else {
-		struct pci_dev *dev = entry->dev;
 		int pos = dev->msi_cap;
 		u16 msgctl;
 
@@ -341,34 +355,27 @@ void __write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 	entry->msg = *msg;
 }
 
-void write_msi_msg(unsigned int irq, struct msi_msg *msg)
+void pci_write_msi_msg(unsigned int irq, struct msi_msg *msg)
 {
 	struct msi_desc *entry = irq_get_msi_desc(irq);
 
-	__write_msi_msg(entry, msg);
+	__pci_write_msi_msg(entry, msg);
 }
-EXPORT_SYMBOL_GPL(write_msi_msg);
+EXPORT_SYMBOL_GPL(pci_write_msi_msg);
 
 static void free_msi_irqs(struct pci_dev *dev)
 {
 	struct msi_desc *entry, *tmp;
 	struct attribute **msi_attrs;
 	struct device_attribute *dev_attr;
-	int count = 0;
+	int i, count = 0;
 
-	list_for_each_entry(entry, &dev->msi_list, list) {
-		int i, nvec;
-		if (!entry->irq)
-			continue;
-		if (entry->nvec_used)
-			nvec = entry->nvec_used;
-		else
-			nvec = 1 << entry->msi_attrib.multiple;
-		for (i = 0; i < nvec; i++)
-			BUG_ON(irq_has_action(entry->irq + i));
-	}
+	list_for_each_entry(entry, &dev->msi_list, list)
+		if (entry->irq)
+			for (i = 0; i < entry->nvec_used; i++)
+				BUG_ON(irq_has_action(entry->irq + i));
 
-	arch_teardown_msi_irqs(dev);
+	pci_msi_teardown_msi_irqs(dev);
 
 	list_for_each_entry_safe(entry, tmp, &dev->msi_list, list) {
 		if (entry->msi_attrib.is_msix) {
@@ -426,7 +433,7 @@ static void __pci_restore_msi_state(struct pci_dev *dev)
 	entry = irq_get_msi_desc(dev->irq);
 
 	pci_intx_for_msi(dev, 0);
-	msi_set_enable(dev, 0);
+	pci_msi_set_enable(dev, 0);
 	arch_restore_msi_irqs(dev);
 
 	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
@@ -447,15 +454,14 @@ static void __pci_restore_msix_state(struct pci_dev *dev)
 
 	/* route the table */
 	pci_intx_for_msi(dev, 0);
-	msix_clear_and_set_ctrl(dev, 0,
+	pci_msix_clear_and_set_ctrl(dev, 0,
 				PCI_MSIX_FLAGS_ENABLE | PCI_MSIX_FLAGS_MASKALL);
 
 	arch_restore_msi_irqs(dev);
-	list_for_each_entry(entry, &dev->msi_list, list) {
+	list_for_each_entry(entry, &dev->msi_list, list)
 		msix_mask_irq(entry, entry->masked);
-	}
 
-	msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0);
+	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0);
 }
 
 void pci_restore_msi_state(struct pci_dev *dev)
@@ -497,9 +503,8 @@ static int populate_msi_sysfs(struct pci_dev *pdev)
 	int count = 0;
 
 	/* Determine how many msi entries we have */
-	list_for_each_entry(entry, &pdev->msi_list, list) {
+	list_for_each_entry(entry, &pdev->msi_list, list)
 		++num_msi;
-	}
 	if (!num_msi)
 		return 0;
 
@@ -559,7 +564,7 @@ error_attrs:
 	return ret;
 }
 
-static struct msi_desc *msi_setup_entry(struct pci_dev *dev)
+static struct msi_desc *msi_setup_entry(struct pci_dev *dev, int nvec)
 {
 	u16 control;
 	struct msi_desc *entry;
@@ -577,6 +582,8 @@ static struct msi_desc *msi_setup_entry(struct pci_dev *dev)
 	entry->msi_attrib.maskbit	= !!(control & PCI_MSI_FLAGS_MASKBIT);
 	entry->msi_attrib.default_irq	= dev->irq;	/* Save IOAPIC IRQ */
 	entry->msi_attrib.multi_cap	= (control & PCI_MSI_FLAGS_QMASK) >> 1;
+	entry->msi_attrib.multiple	= ilog2(__roundup_pow_of_two(nvec));
+	entry->nvec_used		= nvec;
 
 	if (control & PCI_MSI_FLAGS_64BIT)
 		entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_64;
@@ -621,9 +628,9 @@ static int msi_capability_init(struct pci_dev *dev, int nvec)
 	int ret;
 	unsigned mask;
 
-	msi_set_enable(dev, 0);	/* Disable MSI during set up */
+	pci_msi_set_enable(dev, 0);	/* Disable MSI during set up */
 
-	entry = msi_setup_entry(dev);
+	entry = msi_setup_entry(dev, nvec);
 	if (!entry)
 		return -ENOMEM;
 
@@ -634,7 +641,7 @@ static int msi_capability_init(struct pci_dev *dev, int nvec)
 	list_add_tail(&entry->list, &dev->msi_list);
 
 	/* Configure MSI capability structure */
-	ret = arch_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSI);
+	ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSI);
 	if (ret) {
 		msi_mask_irq(entry, mask, ~mask);
 		free_msi_irqs(dev);
@@ -657,7 +664,7 @@ static int msi_capability_init(struct pci_dev *dev, int nvec)
 
 	/* Set MSI enabled bits	 */
 	pci_intx_for_msi(dev, 0);
-	msi_set_enable(dev, 1);
+	pci_msi_set_enable(dev, 1);
 	dev->msi_enabled = 1;
 
 	dev->irq = entry->irq;
@@ -701,6 +708,7 @@ static int msix_setup_entries(struct pci_dev *dev, void __iomem *base,
 		entry->msi_attrib.entry_nr	= entries[i].entry;
 		entry->msi_attrib.default_irq	= dev->irq;
 		entry->mask_base		= base;
+		entry->nvec_used		= 1;
 
 		list_add_tail(&entry->list, &dev->msi_list);
 	}
@@ -719,7 +727,6 @@ static void msix_program_entries(struct pci_dev *dev,
 						PCI_MSIX_ENTRY_VECTOR_CTRL;
 
 		entries[i].vector = entry->irq;
-		irq_set_msi_desc(entry->irq, entry);
 		entry->masked = readl(entry->mask_base + offset);
 		msix_mask_irq(entry, 1);
 		i++;
@@ -744,7 +751,7 @@ static int msix_capability_init(struct pci_dev *dev,
 	void __iomem *base;
 
 	/* Ensure MSI-X is disabled while it is set up */
-	msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
+	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
 
 	pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control);
 	/* Request & Map MSI-X table region */
@@ -756,7 +763,7 @@ static int msix_capability_init(struct pci_dev *dev,
 	if (ret)
 		return ret;
 
-	ret = arch_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX);
+	ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX);
 	if (ret)
 		goto out_avail;
 
@@ -770,7 +777,7 @@ static int msix_capability_init(struct pci_dev *dev,
 	 * MSI-X registers.  We need to mask all the vectors to prevent
 	 * interrupts coming in before they're fully set up.
 	 */
-	msix_clear_and_set_ctrl(dev, 0,
+	pci_msix_clear_and_set_ctrl(dev, 0,
 				PCI_MSIX_FLAGS_MASKALL | PCI_MSIX_FLAGS_ENABLE);
 
 	msix_program_entries(dev, entries);
@@ -783,7 +790,7 @@ static int msix_capability_init(struct pci_dev *dev,
 	pci_intx_for_msi(dev, 0);
 	dev->msix_enabled = 1;
 
-	msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0);
+	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0);
 
 	return 0;
 
@@ -888,14 +895,14 @@ void pci_msi_shutdown(struct pci_dev *dev)
 	BUG_ON(list_empty(&dev->msi_list));
 	desc = list_first_entry(&dev->msi_list, struct msi_desc, list);
 
-	msi_set_enable(dev, 0);
+	pci_msi_set_enable(dev, 0);
 	pci_intx_for_msi(dev, 1);
 	dev->msi_enabled = 0;
 
 	/* Return the device with MSI unmasked as initial states */
 	mask = msi_mask(desc->msi_attrib.multi_cap);
 	/* Keep cached state to be restored */
-	arch_msi_mask_irq(desc, mask, ~mask);
+	__pci_msi_desc_mask_irq(desc, mask, ~mask);
 
 	/* Restore dev->irq to its default pin-assertion irq */
 	dev->irq = desc->msi_attrib.default_irq;
@@ -993,10 +1000,10 @@ void pci_msix_shutdown(struct pci_dev *dev)
 	/* Return the device with MSI-X masked as initial states */
 	list_for_each_entry(entry, &dev->msi_list, list) {
 		/* Keep cached states to be restored */
-		arch_msix_mask_irq(entry, 1);
+		__pci_msix_desc_mask_irq(entry, 1);
 	}
 
-	msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
+	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
 	pci_intx_for_msi(dev, 1);
 	dev->msix_enabled = 0;
 }
@@ -1031,18 +1038,6 @@ EXPORT_SYMBOL(pci_msi_enabled);
 void pci_msi_init_pci_dev(struct pci_dev *dev)
 {
 	INIT_LIST_HEAD(&dev->msi_list);
-
-	/* Disable the msi hardware to avoid screaming interrupts
-	 * during boot.  This is the power on reset default so
-	 * usually this should be a noop.
-	 */
-	dev->msi_cap = pci_find_capability(dev, PCI_CAP_ID_MSI);
-	if (dev->msi_cap)
-		msi_set_enable(dev, 0);
-
-	dev->msix_cap = pci_find_capability(dev, PCI_CAP_ID_MSIX);
-	if (dev->msix_cap)
-		msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
 }
 
 /**
@@ -1138,3 +1133,212 @@ int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries,
 	return nvec;
 }
 EXPORT_SYMBOL(pci_enable_msix_range);
+
+void *msi_desc_to_pci_sysdata(struct msi_desc *desc)
+{
+	struct pci_dev *dev = msi_desc_to_pci_dev(desc);
+
+	return dev->bus->sysdata;
+}
+EXPORT_SYMBOL_GPL(msi_desc_to_pci_sysdata);
+
+#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
+/**
+ * pci_msi_domain_write_msg - Helper to write MSI message to PCI config space
+ * @irq_data:	Pointer to interrupt data of the MSI interrupt
+ * @msg:	Pointer to the message
+ */
+void pci_msi_domain_write_msg(struct irq_data *irq_data, struct msi_msg *msg)
+{
+	struct msi_desc *desc = irq_data->msi_desc;
+
+	/*
+	 * For MSI-X desc->irq is always equal to irq_data->irq. For
+	 * MSI only the first interrupt of MULTI MSI passes the test.
+	 */
+	if (desc->irq == irq_data->irq)
+		__pci_write_msi_msg(desc, msg);
+}
+
+/**
+ * pci_msi_domain_calc_hwirq - Generate a unique ID for an MSI source
+ * @dev:	Pointer to the PCI device
+ * @desc:	Pointer to the msi descriptor
+ *
+ * The ID number is only used within the irqdomain.
+ */
+irq_hw_number_t pci_msi_domain_calc_hwirq(struct pci_dev *dev,
+					  struct msi_desc *desc)
+{
+	return (irq_hw_number_t)desc->msi_attrib.entry_nr |
+		PCI_DEVID(dev->bus->number, dev->devfn) << 11 |
+		(pci_domain_nr(dev->bus) & 0xFFFFFFFF) << 27;
+}
+
+static inline bool pci_msi_desc_is_multi_msi(struct msi_desc *desc)
+{
+	return !desc->msi_attrib.is_msix && desc->nvec_used > 1;
+}
+
+/**
+ * pci_msi_domain_check_cap - Verify that @domain supports the capabilities for @dev
+ * @domain:	The interrupt domain to check
+ * @info:	The domain info for verification
+ * @dev:	The device to check
+ *
+ * Returns:
+ *  0 if the functionality is supported
+ *  1 if Multi MSI is requested, but the domain does not support it
+ *  -ENOTSUPP otherwise
+ */
+int pci_msi_domain_check_cap(struct irq_domain *domain,
+			     struct msi_domain_info *info, struct device *dev)
+{
+	struct msi_desc *desc = first_pci_msi_entry(to_pci_dev(dev));
+
+	/* Special handling to support pci_enable_msi_range() */
+	if (pci_msi_desc_is_multi_msi(desc) &&
+	    !(info->flags & MSI_FLAG_MULTI_PCI_MSI))
+		return 1;
+	else if (desc->msi_attrib.is_msix && !(info->flags & MSI_FLAG_PCI_MSIX))
+		return -ENOTSUPP;
+
+	return 0;
+}
+
+static int pci_msi_domain_handle_error(struct irq_domain *domain,
+				       struct msi_desc *desc, int error)
+{
+	/* Special handling to support pci_enable_msi_range() */
+	if (pci_msi_desc_is_multi_msi(desc) && error == -ENOSPC)
+		return 1;
+
+	return error;
+}
+
+#ifdef GENERIC_MSI_DOMAIN_OPS
+static void pci_msi_domain_set_desc(msi_alloc_info_t *arg,
+				    struct msi_desc *desc)
+{
+	arg->desc = desc;
+	arg->hwirq = pci_msi_domain_calc_hwirq(msi_desc_to_pci_dev(desc),
+					       desc);
+}
+#else
+#define pci_msi_domain_set_desc		NULL
+#endif
+
+static struct msi_domain_ops pci_msi_domain_ops_default = {
+	.set_desc	= pci_msi_domain_set_desc,
+	.msi_check	= pci_msi_domain_check_cap,
+	.handle_error	= pci_msi_domain_handle_error,
+};
+
+static void pci_msi_domain_update_dom_ops(struct msi_domain_info *info)
+{
+	struct msi_domain_ops *ops = info->ops;
+
+	if (ops == NULL) {
+		info->ops = &pci_msi_domain_ops_default;
+	} else {
+		if (ops->set_desc == NULL)
+			ops->set_desc = pci_msi_domain_set_desc;
+		if (ops->msi_check == NULL)
+			ops->msi_check = pci_msi_domain_check_cap;
+		if (ops->handle_error == NULL)
+			ops->handle_error = pci_msi_domain_handle_error;
+	}
+}
+
+static void pci_msi_domain_update_chip_ops(struct msi_domain_info *info)
+{
+	struct irq_chip *chip = info->chip;
+
+	BUG_ON(!chip);
+	if (!chip->irq_write_msi_msg)
+		chip->irq_write_msi_msg = pci_msi_domain_write_msg;
+}
+
+/**
+ * pci_msi_create_irq_domain - Creat a MSI interrupt domain
+ * @node:	Optional device-tree node of the interrupt controller
+ * @info:	MSI domain info
+ * @parent:	Parent irq domain
+ *
+ * Updates the domain and chip ops and creates a MSI interrupt domain.
+ *
+ * Returns:
+ * A domain pointer or NULL in case of failure.
+ */
+struct irq_domain *pci_msi_create_irq_domain(struct device_node *node,
+					     struct msi_domain_info *info,
+					     struct irq_domain *parent)
+{
+	struct irq_domain *domain;
+
+	if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS)
+		pci_msi_domain_update_dom_ops(info);
+	if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
+		pci_msi_domain_update_chip_ops(info);
+
+	domain = msi_create_irq_domain(node, info, parent);
+	if (!domain)
+		return NULL;
+
+	domain->bus_token = DOMAIN_BUS_PCI_MSI;
+	return domain;
+}
+
+/**
+ * pci_msi_domain_alloc_irqs - Allocate interrupts for @dev in @domain
+ * @domain:	The interrupt domain to allocate from
+ * @dev:	The device for which to allocate
+ * @nvec:	The number of interrupts to allocate
+ * @type:	Unused to allow simpler migration from the arch_XXX interfaces
+ *
+ * Returns:
+ * A virtual interrupt number or an error code in case of failure
+ */
+int pci_msi_domain_alloc_irqs(struct irq_domain *domain, struct pci_dev *dev,
+			      int nvec, int type)
+{
+	return msi_domain_alloc_irqs(domain, &dev->dev, nvec);
+}
+
+/**
+ * pci_msi_domain_free_irqs - Free interrupts for @dev in @domain
+ * @domain:	The interrupt domain
+ * @dev:	The device for which to free interrupts
+ */
+void pci_msi_domain_free_irqs(struct irq_domain *domain, struct pci_dev *dev)
+{
+	msi_domain_free_irqs(domain, &dev->dev);
+}
+
+/**
+ * pci_msi_create_default_irq_domain - Create a default MSI interrupt domain
+ * @node:	Optional device-tree node of the interrupt controller
+ * @info:	MSI domain info
+ * @parent:	Parent irq domain
+ *
+ * Returns: A domain pointer or NULL in case of failure. If successful
+ * the default PCI/MSI irqdomain pointer is updated.
+ */
+struct irq_domain *pci_msi_create_default_irq_domain(struct device_node *node,
+		struct msi_domain_info *info, struct irq_domain *parent)
+{
+	struct irq_domain *domain;
+
+	mutex_lock(&pci_msi_domain_lock);
+	if (pci_msi_default_domain) {
+		pr_err("PCI: default irq domain for PCI MSI has already been created.\n");
+		domain = NULL;
+	} else {
+		domain = pci_msi_create_irq_domain(node, info, parent);
+		pci_msi_default_domain = domain;
+	}
+	mutex_unlock(&pci_msi_domain_lock);
+
+	return domain;
+}
+#endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */