i386/pc386: Fix interrupt support.

Fix the interrupt and stop the spurious interrupt from happening.

The fix moves the EOI to C code and cleans that functionality out
of the asm part of the ISR handler.

The code checks the ISR and IRR registers on the enable.

Only ack the master for a slave IRQ if the slave has no other pending
requests.

1 files changed, 31 insertions, 24 deletions

diff --git a/c/src/lib/libbsp/i386/shared/irq/irq.h b/c/src/lib/libbsp/i386/shared/irq/irq.h
index 095af423cf..953774e0ab 100644
--- a/c/src/lib/libbsp/i386/shared/irq/irq.h
+++ b/c/src/lib/libbsp/i386/shared/irq/irq.h
@@ -50,30 +50,37 @@ extern "C" {
 | Constants
 +--------------------------------------------------------------------------*/
 
-    /** @brief Base vector for our IRQ handlers. */
+/** @brief Base vector for our IRQ handlers. */
 #define BSP_IRQ_VECTOR_BASE		BSP_ASM_IRQ_VECTOR_BASE
-#define BSP_IRQ_LINES_NUMBER    	17
-#define BSP_LOWEST_OFFSET		0
-#define BSP_MAX_ON_i8259S		(BSP_IRQ_LINES_NUMBER - 2)
-#define BSP_MAX_OFFSET		 	(BSP_IRQ_LINES_NUMBER - 1)
-    /** @brief
-     * Interrupt offset in comparison to BSP_ASM_IRQ_VECTOR_BASE
-     * NB : 1) Interrupt vector number in IDT = offset + BSP_ASM_IRQ_VECTOR_BASE
-     * 	    2) The same name should be defined on all architecture
-     *	       so that handler connection can be unchanged.
-     */
-#define BSP_PERIODIC_TIMER      0
-#define BSP_KEYBOARD          	1
-#define BSP_UART_COM2_IRQ	3
-#define BSP_UART_COM1_IRQ	4
+#define BSP_IRQ_LINES_NUMBER    	16
+#define BSP_IRQ_MAX_ON_i8259A		(BSP_IRQ_LINES_NUMBER - 1)
+
+/*
+ * Define the number of valid vectors. This is different to the number of IRQ
+ * signals supported. Use this value to allocation vector data or range check.
+ */
+#define BSP_IRQ_VECTOR_NUMBER        17
+#define BSP_IRQ_VECTOR_LOWEST_OFFSET 0
+#define BSP_IRQ_VECTOR_MAX_OFFSET    (BSP_IRQ_VECTOR_NUMBER - 1)
+
+/** @brief
+ * Interrupt offset in comparison to BSP_ASM_IRQ_VECTOR_BASE
+ * NB : 1) Interrupt vector number in IDT = offset + BSP_ASM_IRQ_VECTOR_BASE
+ * 	    2) The same name should be defined on all architecture
+ *	       so that handler connection can be unchanged.
+ */
+#define BSP_PERIODIC_TIMER      0 /* fixed on all builds of PC */
+#define BSP_KEYBOARD          	1 /* fixed on all builds of PC */
+#define BSP_UART_COM2_IRQ	3 /* fixed for ISA bus */
+#define BSP_UART_COM1_IRQ	4 /* fixed for ISA bus */
 #define BSP_UART_COM3_IRQ	5
 #define BSP_UART_COM4_IRQ	6
 #define BSP_RT_TIMER1	      	8
 #define BSP_RT_TIMER3		10
-#define BSP_SMP_IPI   		16
+#define BSP_SMP_IPI   		16 /* not part of the ATPIC */
 
-#define BSP_INTERRUPT_VECTOR_MIN BSP_LOWEST_OFFSET
-#define BSP_INTERRUPT_VECTOR_MAX BSP_MAX_OFFSET
+#define BSP_INTERRUPT_VECTOR_MIN BSP_IRQ_VECTOR_LOWEST_OFFSET
+#define BSP_INTERRUPT_VECTOR_MAX BSP_IRQ_VECTOR_MAX_OFFSET
 
 /** @brief
  * Type definition for RTEMS managed interrupts
@@ -83,7 +90,7 @@ typedef unsigned short rtems_i8259_masks;
 /**
  * @brief Contains the current IMR of both i8259s.
  */
-extern rtems_i8259_masks i8259s_cache;
+//extern rtems_i8259_masks i8259s_cache;
 
 /**
  * @brief Contains the super IMR of both i8259s to overrule i8259s_cache during
@@ -92,7 +99,7 @@ extern rtems_i8259_masks i8259s_cache;
  * This enables a bsp_interrupt_vector_disable() in interrupt handlers.  This
  * is required for the interrupt server support used by the new network stack.
  */
-extern rtems_i8259_masks i8259s_super_imr;
+//extern rtems_i8259_masks i8259s_super_imr;
 
 /*-------------------------------------------------------------------------+
 | Function Prototypes.
@@ -106,13 +113,13 @@ extern rtems_i8259_masks i8259s_super_imr;
  * this function, even if the device asserts the interrupt line it will
  * not be propagated further to the processor
  */
-int BSP_irq_disable_at_i8259s        (const rtems_irq_number irqLine);
+//int BSP_irq_disable_at_i8259s        (const rtems_irq_number irqLine);
 /** @brief
  * function to enable a particular irq at 8259 level. After calling
  * this function, if the device asserts the interrupt line it will
  * be propagated further to the processor
  */
-int BSP_irq_enable_at_i8259s		(const rtems_irq_number irqLine);
+//int BSP_irq_enable_at_i8259s		(const rtems_irq_number irqLine);
 /** @brief
  * function to acknoledge a particular irq at 8259 level. After calling
  * this function, if a device asserts an enabled interrupt line it will
@@ -120,11 +127,11 @@ int BSP_irq_enable_at_i8259s		(const rtems_irq_number irqLine);
  * writting raw handlers as this is automagically done for rtems managed
  * handlers.
  */
-int BSP_irq_ack_at_i8259s           	(const rtems_irq_number irqLine);
+//int BSP_irq_ack_at_i8259s           	(const rtems_irq_number irqLine);
 /** @brief
  * function to check if a particular irq is enabled at 8259 level. After calling
  */
-int BSP_irq_enabled_at_i8259s        	(const rtems_irq_number irqLine);
+//int BSP_irq_enabled_at_i8259s        	(const rtems_irq_number irqLine);
 
 /** @} */