diff options
Diffstat (limited to 'drivers/pci/msi.c')
| -rw-r--r-- | drivers/pci/msi.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 896a15d70f5..44f15ff70c1 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -103,6 +103,16 @@ static void msix_set_enable(struct pci_dev *dev, int enable) } } +/* + * Essentially, this is ((1 << (1 << x)) - 1), but without the + * undefinedness of a << 32. + */ +static inline __attribute_const__ u32 msi_mask(unsigned x) +{ + static const u32 mask[] = { 1, 2, 4, 0xf, 0xff, 0xffff, 0xffffffff }; + return mask[x]; +} + static void msix_flush_writes(struct irq_desc *desc) { struct msi_desc *entry; @@ -407,8 +417,7 @@ static int msi_capability_init(struct pci_dev *dev) /* All MSIs are unmasked by default, Mask them all */ pci_read_config_dword(dev, base, &maskbits); - temp = (1 << multi_msi_capable(control)); - temp = ((temp - 1) & ~temp); + temp = msi_mask((control & PCI_MSI_FLAGS_QMASK) >> 1); maskbits |= temp; pci_write_config_dword(dev, base, maskbits); entry->msi_attrib.maskbits_mask = temp; |