[PATCH v6 03/29] x86/apic/msi: Set the delivery mode individually for each IRQ

[Ricardo Neri]

There are no restrictions in hardware to set  MSI messages with its
own delivery mode. Use the mode specified in the provided IRQ hardware
configuration data. Since most of the IRQs are configured to use the
delivery mode of the APIC driver in use (set in all of them to
APIC_DELIVERY_MODE_FIXED), the only functional changes are where
IRQs are configured to use a specific delivery mode.

Changing the utility function __irq_msi_compose_msg() takes care of
implementing the change in the in the local APIC, PCI-MSI, and DMAR-MSI
irq_chips.

The IO-APIC irq_chip configures the entries in the interrupt redirection
table using the delivery mode specified in the corresponding MSI message.
Since the MSI message is composed by a higher irq_chip in the hierarchy,
it does not need to be updated.

Cc: Andi Kleen <ak at linux.intel.com>
Cc: "Ravi V. Shankar" <ravi.v.shankar at intel.com>
Cc: Stephane Eranian <eranian at google.com>
Cc: iommu at lists.linux-foundation.org
Cc: linuxppc-dev at lists.ozlabs.org
Cc: x86 at kernel.org
Reviewed-by: Tony Luck <tony.luck at intel.com>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon at linux.intel.com>
---
Changes since v5:
 * Introduced this patch

Changes since v4:
 * N/A

Changes since v3:
 * N/A

Changes since v2:
 * N/A

Changes since v1:
 * N/A
---
 arch/x86/kernel/apic/apic.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 189d3a5e471a..d1e12da1e9af 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -2528,7 +2528,7 @@ void __irq_msi_compose_msg(struct irq_cfg *cfg, struct msi_msg *msg,
 	msg->arch_addr_lo.dest_mode_logical = apic->dest_mode_logical;
 	msg->arch_addr_lo.destid_0_7 = cfg->dest_apicid & 0xFF;
 
-	msg->arch_data.delivery_mode = APIC_DELIVERY_MODE_FIXED;
+	msg->arch_data.delivery_mode = cfg->delivery_mode;
 	msg->arch_data.vector = cfg->vector;
 
 	msg->address_hi = X86_MSI_BASE_ADDRESS_HIGH;
-- 
2.17.1