Commit a52e2e35 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki Committed by Jesse Barnes
Browse files

PCI/MSI: Introduce pci_msix_table_size() 



Introduce new function pci_msix_table_size() returning the size of
the MSI-X table of given PCI device or 0 if the device doesn't
support MSI-X.

Signed-off-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: default avatarHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: default avatarJesse Barnes <jbarnes@virtuousgeek.org>
parent a447b772

drivers/pci/msi.c

+19 −5
Original line number Diff line number Diff line
@@ -674,6 +674,23 @@ static int msi_free_irqs(struct pci_dev* dev) 
	return 0;

}



/**

 * pci_msix_table_size - return the number of device's MSI-X table entries

 * @dev: pointer to the pci_dev data structure of MSI-X device function

 */

int pci_msix_table_size(struct pci_dev *dev)

{

	int pos;

	u16 control;



	pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);

	if (!pos)

		return 0;



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

	return multi_msix_capable(control);

}



/**

 * pci_enable_msix - configure device's MSI-X capability structure

 * @dev: pointer to the pci_dev data structure of MSI-X device function
@@ -691,9 +708,8 @@ static int msi_free_irqs(struct pci_dev* dev) 
 **/

int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec)

{

	int status, pos, nr_entries;

	int status, nr_entries;

	int i, j;

	u16 control;



	if (!entries)

 		return -EINVAL;
@@ -702,9 +718,7 @@ int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec) 
	if (status)

		return status;



	pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);

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

	nr_entries = multi_msix_capable(control);

	nr_entries = pci_msix_table_size(dev);

	if (nvec > nr_entries)

		return -EINVAL;

include/linux/pci.h

+5 −0
Original line number Diff line number Diff line
@@ -799,6 +799,10 @@ static inline void pci_msi_shutdown(struct pci_dev *dev) 
static inline void pci_disable_msi(struct pci_dev *dev)

{ }



static inline int pci_msix_table_size(struct pci_dev *dev)

{

	return 0;

}

static inline int pci_enable_msix(struct pci_dev *dev,

				  struct msix_entry *entries, int nvec)

{
@@ -823,6 +827,7 @@ static inline int pci_msi_enabled(void) 
extern int pci_enable_msi(struct pci_dev *dev);

extern void pci_msi_shutdown(struct pci_dev *dev);

extern void pci_disable_msi(struct pci_dev *dev);

extern int pci_msix_table_size(struct pci_dev *dev);

extern int pci_enable_msix(struct pci_dev *dev,

	struct msix_entry *entries, int nvec);

extern void pci_msix_shutdown(struct pci_dev *dev);

CRA Git | Maintained and supported by SUSTech CRA and CCSE