Currently special(system) irq definition layout is a bit random, due to quite
a long period of code shuffle and refactorization, making native_init_IRQ()
quit hard to follow.
Besides, there are also some leftovers on the vector layout comment.
For example, INVALIDATE_TLB_VECTOR_START vectors have gone by using generic IPI
mechanism(see commit 52aec3308db8). VSYSCALL_EMU_VECTOR is also gone because
vsyscalls are emulated by instruction fault traps(see commit 3ae36655b97a).
So this patch aims at refactoring the special(system) irq vector layout and
cleanup.
New system irq vectors layout are now look like:
0xff, 0xfe:
Two highest vectors, assigned to spurious vector and error vector.
Also add sanity check for error vector definition:
SPURIOUS_APIC_VECTOR 0xff
ERROR_APIC_VECTOR 0xfe
0xfd - 0xf9:
CONFIG_SMP dependent vectors. On morden machines these are achieved
via local APIC, but not neccessary:
RESCHEDULE_VECTOR 0xfd
CALL_FUNCTION_VECTOR 0xfc
CALL_FUNCTION_SINGLE_VECTOR 0xfb
REBOOT_VECTOR 0xfa
X86_PLATFORM_IPI_VECTOR 0xf9
0xf8 - 0xf0:
Local APIC dependent vectors. Some are only depending on Local ACPI,
but some are depending on more.
IRQ_WORK is not neccessarily depending on SMP, but currently it depends
on X86_LOCAL_APIC. Werid, just leav it as-is:
IRQ_WORK_VECTOR 0xf8
Below are all depending on X86_LOCAL_APIC, some depend on more(MCE,
Virt, etc):
THERMAL_APIC_VECTOR 0xf7
THRESHOLD_APIC_VECTOR 0xf6
UV_BAU_MESSAGE 0xf5
DEFERRED_ERROR_VECTOR 0xf4
HYPERVISOR_CALLBACK_VECTOR 0xf3
POSTED_INTR_VECTOR 0xf2
POSTED_INTR_WAKEUP_VECTOR 0xf1
/* 0xf0 is currently not used */
0xef:
Local APIC timer vector 0xef
Once this layout is applied, next patch will arrange native_init_IRQ() per this
layout.
Signed-off-by: Jianyu Zhan <[email protected]>
---
arch/x86/include/asm/irq_vectors.h | 72 +++++++++++++++++++++++++++++---------
1 file changed, 55 insertions(+), 17 deletions(-)
diff --git a/arch/x86/include/asm/irq_vectors.h
b/arch/x86/include/asm/irq_vectors.h
index 6ca9fd6..b785a19 100644
--- a/arch/x86/include/asm/irq_vectors.h
+++ b/arch/x86/include/asm/irq_vectors.h
@@ -17,8 +17,9 @@
* Vectors 0 ... 31 : system traps and exceptions - hardcoded events
* Vectors 32 ... 127 : device interrupts
* Vector 128 : legacy int80 syscall interface
- * Vectors 129 ... INVALIDATE_TLB_VECTOR_START-1 except 204 : device
interrupts
- * Vectors INVALIDATE_TLB_VECTOR_START ... 255 : special interrupts
+ * Vectors 129 ... 238 : device interrupts
+ * Vectors 239(0xef) : special(system) interrupt LOCAL_TIMER_VECTOR
+ * Vectors 240 ... 255 : special(system) interrupts, see definition below for
details.
*
* 64-bit x86 has per CPU IDT tables, 32-bit has one shared IDT table.
*
@@ -55,40 +56,71 @@
#define ISA_IRQ_VECTOR(irq) (((FIRST_EXTERNAL_VECTOR + 16) & ~15) +
irq)
/*
- * Special IRQ vectors used by the SMP architecture, 0xf0-0xff
+ * Special IRQ vectors: 0xef - 0xff, for system vectors.
*
* some of the following vectors are 'rare', they are merged
* into a single vector (CALL_FUNCTION_VECTOR) to save vector space.
* TLB, reschedule and local APIC vectors are performance-critical.
+ *
+ * Layout:
+ * 0xff, 0xfe:
+ * Two highest vectors, granted for spurious vector and error vector.
+ * 0xfd - 0xf9:
+ * CONFIG_SMP dependent vectors. On morden machines these are achieved
+ * via local APIC, but not neccessary.
+ * 0xf8 - 0xf0:
+ * Local APIC dependent vectors. Some are only depending on Local ACPI,
+ * but some are depending on more.
+ * 0xef:
+ * Local APIC timer vector.
*/
-#define SPURIOUS_APIC_VECTOR 0xff
/*
- * Sanity check
+ * Grant highest 2 vectors for two special vectors:
+ * Spurious Vector and Error Vector.
*/
-#if ((SPURIOUS_APIC_VECTOR & 0x0F) != 0x0F)
-# error SPURIOUS_APIC_VECTOR definition error
+#define SPURIOUS_APIC_VECTOR 0xff
+#define ERROR_APIC_VECTOR 0xfe
+
+#if SPURIOUS_APIC_VECTOR != 0xff
+# error SPURIOUS_APIC_VECTOR definition error, should grant it: 0xff
#endif
-#define ERROR_APIC_VECTOR 0xfe
+#if ERROR_APIC_VECTOR != 0xfe
+# error ERROR_APIC_VECTOR definition error, should grant it: 0xfe
+#endif
+
+
+/*
+ * SMP dependent vectors
+ */
+/* CPU-to-CPU reschedule-helper IPI, driven by wakeup.*/
#define RESCHEDULE_VECTOR 0xfd
+
+/* IPI for generic function call */
#define CALL_FUNCTION_VECTOR 0xfc
+
+/* IPI for generic single function call */
#define CALL_FUNCTION_SINGLE_VECTOR 0xfb
-#define THERMAL_APIC_VECTOR 0xfa
-#define THRESHOLD_APIC_VECTOR 0xf9
-#define REBOOT_VECTOR 0xf8
+
+/* IPI used for rebooting/stopping */
+#define REBOOT_VECTOR 0xfa
+
+/* IPI for X86 platform specific use */
+#define X86_PLATFORM_IPI_VECTOR 0xf9
/*
- * Generic system vector for platform specific use
+ * Local APCI dependent only vectors, these may or may not depend on SMP.
*/
-#define X86_PLATFORM_IPI_VECTOR 0xf7
+/* IRQ work vector: a mechanism that allows running code in IRQ context */
+#define IRQ_WORK_VECTOR 0xf8
-#define POSTED_INTR_WAKEUP_VECTOR 0xf1
/*
- * IRQ work vector:
+ * Local APCI dependent vectors, but also depend on other configurations
+ * (MCE, virtualization, etc)
*/
-#define IRQ_WORK_VECTOR 0xf6
-
+#define THERMAL_APIC_VECTOR 0xf7
+#define THRESHOLD_APIC_VECTOR 0xf6
#define UV_BAU_MESSAGE 0xf5
#define DEFERRED_ERROR_VECTOR 0xf4
@@ -99,6 +131,9 @@
#ifdef CONFIG_HAVE_KVM
#define POSTED_INTR_VECTOR 0xf2
#endif
+#define POSTED_INTR_WAKEUP_VECTOR 0xf1
+
+/* Vector 0xf0 is not used yet, reserved */
/*
* Local APIC timer IRQ vector is on a different priority level,
@@ -107,6 +142,9 @@
*/
#define LOCAL_TIMER_VECTOR 0xef
+/* --- end of special vectors definitions --- */
+
+
#define NR_VECTORS 256
#ifdef CONFIG_X86_LOCAL_APIC
--
2.4.3
