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From: Jacob Pan <jacob.jun.pan@linux.intel.com>
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	Jacob Pan <jacob.jun.pan@linux.intel.com>
Subject: [PATCH v3  05/12] x86/irq: Reserve a per CPU IDT vector for posted MSIs
Date: Tue, 23 Apr 2024 10:41:07 -0700
Message-Id: <20240423174114.526704-6-jacob.jun.pan@linux.intel.com>
In-Reply-To: <20240423174114.526704-1-jacob.jun.pan@linux.intel.com>
References: <20240423174114.526704-1-jacob.jun.pan@linux.intel.com>
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When posted MSI is enabled, all device MSIs are multiplexed into a single
notification vector. MSI handlers will be de-multiplexed at run-time by
system software without IDT delivery.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>

---
v2:
 - Add missing CONFIG_ in #ifdef
 - Extend changes to x86 tools
---
 arch/x86/include/asm/irq_vectors.h | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/irq_vectors.h b/arch/x86/include/asm/irq_vectors.h
index d18bfb238f66..13aea8fc3d45 100644
--- a/arch/x86/include/asm/irq_vectors.h
+++ b/arch/x86/include/asm/irq_vectors.h
@@ -97,10 +97,16 @@
 
 #define LOCAL_TIMER_VECTOR		0xec
 
+/*
+ * Posted interrupt notification vector for all device MSIs delivered to
+ * the host kernel.
+ */
+#define POSTED_MSI_NOTIFICATION_VECTOR	0xeb
+
 #define NR_VECTORS			 256
 
 #ifdef CONFIG_X86_LOCAL_APIC
-#define FIRST_SYSTEM_VECTOR		LOCAL_TIMER_VECTOR
+#define FIRST_SYSTEM_VECTOR		POSTED_MSI_NOTIFICATION_VECTOR
 #else
 #define FIRST_SYSTEM_VECTOR		NR_VECTORS
 #endif
-- 
2.25.1