Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 520fe9dc authored by Gavin Shan's avatar Gavin Shan Committed by Bjorn Helgaas
Browse files

PCI: Use cached MSI-X cap while enabling MSI-X 



The patch uses the cached MSI-X capability offset in
pci_dev instead of reading it from config space when enabling
MSI-X interrupts.

Signed-off-by: default avatarGavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent f465136d

drivers/pci/msi.c

+16 −20
Original line number Diff line number Diff line
@@ -598,14 +598,14 @@ static int msi_capability_init(struct pci_dev *dev, int nvec) 
	return 0;

}



static void __iomem *msix_map_region(struct pci_dev *dev, unsigned pos,

							unsigned nr_entries)

static void __iomem *msix_map_region(struct pci_dev *dev, unsigned nr_entries)

{

	resource_size_t phys_addr;

	u32 table_offset;

	u8 bir;



	pci_read_config_dword(dev, msix_table_offset_reg(pos), &table_offset);

	pci_read_config_dword(dev,

		msix_table_offset_reg(dev->msix_cap), &table_offset);

	bir = (u8)(table_offset & PCI_MSIX_FLAGS_BIRMASK);

	table_offset &= ~PCI_MSIX_FLAGS_BIRMASK;

	phys_addr = pci_resource_start(dev, bir) + table_offset;
@@ -613,9 +613,8 @@ static void __iomem *msix_map_region(struct pci_dev *dev, unsigned pos, 
	return ioremap_nocache(phys_addr, nr_entries * PCI_MSIX_ENTRY_SIZE);

}



static int msix_setup_entries(struct pci_dev *dev, unsigned pos,

				void __iomem *base, struct msix_entry *entries,

				int nvec)

static int msix_setup_entries(struct pci_dev *dev, void __iomem *base,

			      struct msix_entry *entries, int nvec)

{

	struct msi_desc *entry;

	int i;
@@ -635,7 +634,7 @@ static int msix_setup_entries(struct pci_dev *dev, unsigned pos, 
		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		= pos;

		entry->msi_attrib.pos		= dev->msix_cap;

		entry->mask_base		= base;



		list_add_tail(&entry->list, &dev->msi_list);
@@ -675,23 +674,22 @@ static void msix_program_entries(struct pci_dev *dev, 
static int msix_capability_init(struct pci_dev *dev,

				struct msix_entry *entries, int nvec)

{

	int pos, ret;

	int ret;

	u16 control;

	void __iomem *base;



	pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);

	pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);

	pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control);



	/* Ensure MSI-X is disabled while it is set up */

	control &= ~PCI_MSIX_FLAGS_ENABLE;

	pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);

	pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control);



	/* Request & Map MSI-X table region */

	base = msix_map_region(dev, pos, multi_msix_capable(control));

	base = msix_map_region(dev, multi_msix_capable(control));

	if (!base)

		return -ENOMEM;



	ret = msix_setup_entries(dev, pos, base, entries, nvec);

	ret = msix_setup_entries(dev, base, entries, nvec);

	if (ret)

		return ret;
@@ -705,7 +703,7 @@ static int msix_capability_init(struct pci_dev *dev, 
	 * interrupts coming in before they're fully set up.

	 */

	control |= PCI_MSIX_FLAGS_MASKALL | PCI_MSIX_FLAGS_ENABLE;

	pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);

	pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control);



	msix_program_entries(dev, entries);
@@ -720,7 +718,7 @@ static int msix_capability_init(struct pci_dev *dev, 
	dev->msix_enabled = 1;



	control &= ~PCI_MSIX_FLAGS_MASKALL;

	pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);

	pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control);



	return 0;
@@ -906,14 +904,12 @@ EXPORT_SYMBOL(pci_disable_msi); 
 */

int pci_msix_table_size(struct pci_dev *dev)

{

	int pos;

	u16 control;



	pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);

	if (!pos)

	if (!dev->msix_cap)

		return 0;



	pci_read_config_word(dev, msi_control_reg(pos), &control);

	pci_read_config_word(dev, msi_control_reg(dev->msix_cap), &control);

	return multi_msix_capable(control);

}