[patch RFC 19/38] irqdomain/msi: Provide DOMAIN_BUS_VMD_MSI

Thomas Gleixner
2020-08-21T02:19:08Z

[-- Attachment #1: genirq-msi--Provide-DOMAIN_BUS_VMD_MSI.patch --]
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PCI devices behind a VMD bus are not subject to interrupt remapping, but
the irq domain for VMD MSI cannot be distinguished from a regular PCI/MSI
irq domain.

Add a new domain bus token and allow it in the bus token check in
msi_check_reservation_mode() to keep the functionality the same once VMD
uses this token.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jon Derrick <jonathan.derrick@intel.com>
---
include/linux/irqdomain.h | 1 +
kernel/irq/msi.c | 7 ++++++-
2 files changed, 7 insertions(+), 1 deletion(-)

--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -84,6 +84,7 @@ enum irq_domain_bus_token {
DOMAIN_BUS_FSL_MC_MSI,
DOMAIN_BUS_TI_SCI_INTA_MSI,
DOMAIN_BUS_WAKEUP,
+ DOMAIN_BUS_VMD_MSI,
};

/**
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -370,8 +370,13 @@ static bool msi_check_reservation_mode(s
{
struct msi_desc *desc;

- if (domain->bus_token != DOMAIN_BUS_PCI_MSI)
+ switch(domain->bus_token) {
+ case DOMAIN_BUS_PCI_MSI:
+ case DOMAIN_BUS_VMD_MSI:
+ break;
+ default:
return false;
+ }

if (!(info->flags & MSI_FLAG_MUST_REACTIVATE))
return false;