Hi Eric, On 19/04/16 18:13, Eric Auger wrote:
Let's introduce a new msi_domain_info flag value, MSI_FLAG_IRQ_REMAPPING meant to tell the domain supports IRQ REMAPPING, also known as Interrupt Translation Service. On Intel HW this IRQ remapping capability is abstracted on IOMMU side while on ARM it is abstracted on MSI controller side. This flag will be used to know whether the MSI passthrough is safe.
Perhaps a nitpick, but given the earlier confusion about what the IOMMU flag actually meant this prompts me to wonder if it's worth adjusting the general terminology before we propagate it further. What I think we actually care about is that one thing or the other "provides MSI isolation" rather than "supports MSI remapping", since the latter is all to easy to misinterpret the way we did in the SMMU drivers.
Robin.
Signed-off-by: Eric Auger <[email protected]> --- v4 -> v5: - seperate flag introduction from first user addition (ITS) --- include/linux/msi.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/include/linux/msi.h b/include/linux/msi.h index 8b425c6..08441b1 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -270,6 +270,8 @@ enum { MSI_FLAG_MULTI_PCI_MSI = (1 << 3), /* Support PCI MSIX interrupts */ MSI_FLAG_PCI_MSIX = (1 << 4), + /* Support MSI IRQ remapping service */ + MSI_FLAG_IRQ_REMAPPING = (1 << 5), }; int msi_domain_set_affinity(struct irq_data *data, const struct cpumask *mask,
