Add QEMU interrupt handling (incomplete)

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3339 42af7a65-404d-4744-a932-0658087f49c3

arch/x86/include/i486/arch.h

@@ -81,6 +81,42 @@
 #define X86_EFLAGS_VIP       (1 << 20) /* Bit 20: Virtual Interrupt Pending (Pentium+) */
 #define X86_EFLAGS_ID        (1 << 21) /* Bit 21: CPUID detection flag (Pentium+) */
 
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+/* GDT data structures
+ *
+ * The Global Descriptor Table or GDT is a data structure used by Intel x86-
+ * family processors starting with the 80286 in order to define the
+ * characteristics of the various memory areas used during program execution, 
+ * for example the base address, the size and access privileges like
+ * executability and writability. These memory areas are called segments in
+ * Intel terminology.
+ */
+
+/* This structure defines one segment */
+
+struct gdt_entry_s
+{
+  uint16_t lowlimit;           /* The lower 16 bits of the limit */
+  uint16_t lowbase;            /* The lower 16 bits of the base */
+  uint8_t  midbase;            /* The next 8 bits of the base */
+  uint8_t  access;             /* Access flags, determine ring segment can be used in */
+  uint8_t  granularity;
+  uint8_t  hibase;             /* The last 8 bits of the base */
+} __attribute__((packed));
+
+/* This structure refers to the array of GDT entries, and is in the format
+ * required by the lgdt instruction.
+ */
+
+struct gdt_ptr_s
+{
+  uint16_t limit;               /* The upper 16 bits of all selector limits */
+  uint32_t base;                /* The address of the first gdt_entry_t struct */
+} __attribute__((packed));
+
 /****************************************************************************
  * Inline functions
  ****************************************************************************/

arch/x86/include/qemu/irq.h

@@ -48,7 +48,57 @@
  * Definitions
  ****************************************************************************/
 
-#define NR_IRQS 0
+#define ISR0     0
+#define ISR1     1
+#define ISR2     2
+#define ISR3     3
+#define ISR4     4
+#define ISR5     5
+#define ISR6     6
+#define ISR7     7
+#define ISR8     8
+#define ISR9     9
+#define ISR10   10
+#define ISR11   11
+#define ISR12   12
+#define ISR13   13
+#define ISR14   14
+#define ISR15   15
+#define ISR16   16
+#define ISR17   17
+#define ISR18   18
+#define ISR19   19
+#define ISR20   20
+#define ISR21   21
+#define ISR22   22
+#define ISR23   23
+#define ISR24   24
+#define ISR25   25
+#define ISR26   26
+#define ISR27   27
+#define ISR28   28
+#define ISR29   29
+#define ISR30   30
+#define ISR31   31
+
+#define IRQ0    32
+#define IRQ1    33
+#define IRQ2    34
+#define IRQ3    35
+#define IRQ4    36
+#define IRQ5    37
+#define IRQ6    38
+#define IRQ7    39
+#define IRQ8    40
+#define IRQ9    41
+#define IRQ10   42
+#define IRQ11   43
+#define IRQ12   44
+#define IRQ13   45
+#define IRQ14   46
+#define IRQ15   47
+
+#define NR_IRQS 48
 
 /****************************************************************************
  * Public Types