diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2025-03-19 11:56:57 +0100 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2025-04-09 20:47:30 +0200 |
| commit | d5124a9957b2a8d728a86ea8462e0c404acae016 (patch) | |
| tree | 597d92f7941b0f94f59c0380327fab54575391f6 /drivers/pci/pci.h | |
| parent | 6552e90e2a23b8861488653c76605f7aa1c77ad8 (diff) | |
PCI/MSI: Provide a sane mechanism for TPH
The PCI/TPH driver fiddles with the MSI-X control word of an active
interrupt completely unserialized against concurrent operations issued
from the interrupt core. It also brings the PCI/MSI-X internal cached
control word out of sync.
Provide a function, which has the required serialization and keeps the
control word cache in sync.
Unfortunately this requires to look up and lock the interrupt descriptor,
which should be only done in the interrupt core code. But confining this
particular oddity in the PCI/MSI core is the lesser of all evil. A
interrupt core implementation would require a larger pile of infrastructure
and indirections for dubious value.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/all/20250319105506.683663807@linutronix.de
Diffstat (limited to 'drivers/pci/pci.h')
| -rw-r--r-- | drivers/pci/pci.h | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index b81e99cd4b62..39f368d2f26d 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -1064,6 +1064,15 @@ int pcim_request_region_exclusive(struct pci_dev *pdev, int bar, const char *name); void pcim_release_region(struct pci_dev *pdev, int bar); +#ifdef CONFIG_PCI_MSI +int pci_msix_write_tph_tag(struct pci_dev *pdev, unsigned int index, u16 tag); +#else +static inline int pci_msix_write_tph_tag(struct pci_dev *pdev, unsigned int index, u16 tag) +{ + return -ENODEV; +} +#endif + /* * Config Address for PCI Configuration Mechanism #1 * |