2007-12-02 Till Straumann <strauman@slac.stanford.edu>

	* shared/irq/i8259.c, shared/irq/irq.h, shared/irq/irq_supp.h,
	shared/irq/openpic_i8259_irq.c: BSP_disable_irq_at_pic(),
	openpic_disable_irq(), BSP_irq_disable_at_i8259s() now return
	0/1 if irq was disabled/enabled prior to disabling.
	irq_supp.h now exports a inline helper routine for scanning
	a list of shared handlers; to be used by PIC drivers.

5 files changed, 60 insertions, 33 deletions

diff --git a/c/src/lib/libbsp/powerpc/ChangeLog b/c/src/lib/libbsp/powerpc/ChangeLog
index 0398ef54a2..f830286056 100644
--- a/c/src/lib/libbsp/powerpc/ChangeLog
+++ b/c/src/lib/libbsp/powerpc/ChangeLog
@@ -1,5 +1,14 @@
 2007-12-02	Till Straumann <strauman@slac.stanford.edu>
 
+	* shared/irq/i8259.c, shared/irq/irq.h, shared/irq/irq_supp.h,
+	shared/irq/openpic_i8259_irq.c: BSP_disable_irq_at_pic(),
+	openpic_disable_irq(), BSP_irq_disable_at_i8259s() now return
+	0/1 if irq was disabled/enabled prior to disabling.
+	irq_supp.h now exports a inline helper routine for scanning
+	a list of shared handlers; to be used by PIC drivers.
+
+2007-12-02	Till Straumann <strauman@slac.stanford.edu>
+
 	* shared/openpic/openpic.c shared/openpic/openpic.h,
 	shared/irq/irq_init.c: added more parameters to 
 	openpic_init() so that more details of the configuration
diff --git a/c/src/lib/libbsp/powerpc/shared/irq/i8259.c b/c/src/lib/libbsp/powerpc/shared/irq/i8259.c
index a133d16898..2e700b006d 100644
--- a/c/src/lib/libbsp/powerpc/shared/irq/i8259.c
+++ b/c/src/lib/libbsp/powerpc/shared/irq/i8259.c
@@ -29,21 +29,23 @@ volatile rtems_i8259_masks i8259s_cache = 0xfffb;
 |      Description: Mask IRQ line in appropriate PIC chip.
 | Global Variables: i8259s_cache
 |        Arguments: vector_offset - number of IRQ line to mask.
-|          Returns: Nothing.
+|          Returns: original state or -1 on error.
 +--------------------------------------------------------------------------*/
 int BSP_irq_disable_at_i8259s    (const rtems_irq_number irqLine)
 {
   unsigned short        mask;
   rtems_interrupt_level level;
+  int                   rval;
 
   if ( ((int)irqLine < BSP_ISA_IRQ_LOWEST_OFFSET) ||
        ((int)irqLine > BSP_ISA_IRQ_MAX_OFFSET)
        )
-    return 1;
+    return -1;
 
   rtems_interrupt_disable(level);
 
   mask = 1 << irqLine;
+  rval = i8259s_cache & mask ? 0 : 1;
   i8259s_cache |= mask;
 
   if (irqLine < 8)
@@ -56,7 +58,7 @@ int BSP_irq_disable_at_i8259s    (const rtems_irq_number irqLine)
   }
   rtems_interrupt_enable(level);
 
-  return 0;
+  return rval;
 }
 
 /*-------------------------------------------------------------------------+
diff --git a/c/src/lib/libbsp/powerpc/shared/irq/irq.h b/c/src/lib/libbsp/powerpc/shared/irq/irq.h
index 78ac3b7def..c27c459388 100644
--- a/c/src/lib/libbsp/powerpc/shared/irq/irq.h
+++ b/c/src/lib/libbsp/powerpc/shared/irq/irq.h
@@ -157,6 +157,9 @@ void BSP_i8259s_init(void);
  * function to disable a particular irq at 8259 level. After calling
  * this function, even if the device asserts the interrupt line it will
  * not be propagated further to the processor
+ *
+ * RETURNS: 1/0 if the interrupt was enabled/disabled originally or
+ *          a value < 0 on error.
  */
 int BSP_irq_disable_at_i8259s        (const rtems_irq_number irqLine);
 /*
diff --git a/c/src/lib/libbsp/powerpc/shared/irq/irq_supp.h b/c/src/lib/libbsp/powerpc/shared/irq/irq_supp.h
index c64d587c9f..3a0cd9a866 100644
--- a/c/src/lib/libbsp/powerpc/shared/irq/irq_supp.h
+++ b/c/src/lib/libbsp/powerpc/shared/irq/irq_supp.h
@@ -30,7 +30,11 @@ extern "C" {
  *       PIC(s).
  */
 extern void BSP_enable_irq_at_pic		(const rtems_irq_number irqLine);
-extern void BSP_disable_irq_at_pic		(const rtems_irq_number irqLine);
+/*
+ * RETURNS: nonzero (> 0 ) if irq was enabled originally, zero if irq
+ *          was off and negative value if there was an error.
+ */
+extern int  BSP_disable_irq_at_pic		(const rtems_irq_number irqLine);
 
 /*
  * Initialize the PIC.
@@ -48,6 +52,38 @@ struct _BSP_Exception_frame;
  */
 void C_dispatch_irq_handler (struct _BSP_Exception_frame *frame, unsigned int excNum);
 
+/*
+ * Snippet to be used by PIC drivers;
+ * enables interrupts, traverses list of
+ * shared handlers for a given interrupt
+ * and restores original irq level
+ */
+
+static inline void
+bsp_irq_dispatch_list(rtems_irq_connect_data *tbl, unsigned irq, rtems_irq_hdl sentinel)
+{
+register uint32_t	l_orig;
+
+	l_orig = _ISR_Get_level();
+
+	/* Enable all interrupts */
+	_ISR_Set_level(0);
+
+  /* rtems_hdl_tbl[irq].hdl(rtems_hdl_tbl[irq].handle); */
+  {
+     rtems_irq_connect_data* vchain;
+     for( vchain = &tbl[irq];
+          ((int)vchain != -1 && vchain->hdl != sentinel);
+          vchain = (rtems_irq_connect_data*)vchain->next_handler )
+     {
+        vchain->hdl(vchain->handle);
+     }
+  }
+
+  /* Restore original level */
+  _ISR_Set_level(l_orig);
+}
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/c/src/lib/libbsp/powerpc/shared/irq/openpic_i8259_irq.c b/c/src/lib/libbsp/powerpc/shared/irq/openpic_i8259_irq.c
index edbe581db8..dcc3b645f5 100644
--- a/c/src/lib/libbsp/powerpc/shared/irq/openpic_i8259_irq.c
+++ b/c/src/lib/libbsp/powerpc/shared/irq/openpic_i8259_irq.c
@@ -118,7 +118,7 @@ BSP_enable_irq_at_pic(const rtems_irq_number name)
     }
 }
 
-void
+int
 BSP_disable_irq_at_pic(const rtems_irq_number name)
 {
 #ifdef BSP_PCI_ISA_BRIDGE_IRQ
@@ -126,15 +126,16 @@ BSP_disable_irq_at_pic(const rtems_irq_number name)
       /*
        * disable interrupt at PIC level
        */
-      BSP_irq_disable_at_i8259s ((int) name - BSP_ISA_IRQ_LOWEST_OFFSET);
+      return BSP_irq_disable_at_i8259s ((int) name - BSP_ISA_IRQ_LOWEST_OFFSET);
     }
 #endif
     if (is_pci_irq(name)) {
       /*
        * disable interrupt at OPENPIC level
        */
-      openpic_disable_irq ((int) name - BSP_PCI_IRQ_LOWEST_OFFSET);
+      return openpic_disable_irq ((int) name - BSP_PCI_IRQ_LOWEST_OFFSET);
     }
+	return -1;
 }
 
 /*
@@ -209,30 +210,6 @@ int _BSP_vme_bridge_irq = -1;
 
 unsigned BSP_spuriousIntr = 0;
 
-static inline void
-dispatch_list(unsigned int irq)
-{
-register uint32_t	l_orig;
-
-	l_orig = _ISR_Get_level();
-
-	/* Enable all interrupts */
-	_ISR_Set_level(0);
-
-  /* rtems_hdl_tbl[irq].hdl(rtems_hdl_tbl[irq].handle); */
-  {
-     rtems_irq_connect_data* vchain;
-     for( vchain = &rtems_hdl_tbl[irq];
-          ((int)vchain != -1 && vchain->hdl != default_rtems_entry.hdl);
-          vchain = (rtems_irq_connect_data*)vchain->next_handler )
-     {
-        vchain->hdl(vchain->handle);
-     }
-  }
-
-  /* Restore original level */
-  _ISR_Set_level(l_orig);
-}
 /*
  * High level IRQ handler called from shared_raw_irq_code_entry
  */
@@ -247,7 +224,7 @@ void C_dispatch_irq_handler (BSP_Exception_frame *frame, unsigned int excNum)
 
   if (excNum == ASM_DEC_VECTOR) {
 
-  	dispatch_list(BSP_DECREMENTER);
+  	bsp_irq_dispatch_list(rtems_hdl_tbl, BSP_DECREMENTER, default_rtems_entry.hdl);
 
     return;
 
@@ -282,7 +259,7 @@ void C_dispatch_irq_handler (BSP_Exception_frame *frame, unsigned int excNum)
 #endif
 
   /* dispatch handlers */
-  dispatch_list(irq);
+  bsp_irq_dispatch_list(rtems_hdl_tbl, irq, default_rtems_entry.hdl);
 
 #ifdef BSP_PCI_ISA_BRIDGE_IRQ
   if (isaIntr)  {