2000-11-27 Joel Sherrill <joel@OARcorp.com>

* README, sim68000.setup, clock/clockdrv.c: Modified to add
	support for timer as clock tick source.  Compiles but untested.

c/src/lib/libbsp/m68k/sim68000/README

@@ -4,7 +4,10 @@
 
 BSP for the BSVC 68000 simulator.  This is definitely under construction. 
 The initialization/setup script for BSVC is the part that likely needs
-work.
+work.  I have written the timer based on the timer sample included with
+bsvc 2.1.  
+
+At this point, hello does not even print.
 
 --joel
 1 August 2000

c/src/lib/libbsp/m68k/sim68000/clock/clockdrv.c

@@ -6,17 +6,50 @@
 
 #include <bsp.h>
 
-#define CLOCK_VECTOR 0
+#define CLOCK_VECTOR 84
 
 #define Clock_driver_support_install_isr( _new, _old )  \
   do { _old = (rtems_isr_entry) set_vector( _new, CLOCK_VECTOR, 1 ); } while(0)
 
 
-#define Clock_driver_support_initialize_hardware()
+typedef struct {
+  volatile unsigned8  cr;       /*  0 -  0 : Timer Control Register */
+  volatile unsigned8  pad0;     /*  1 -  1 : pad */
+  volatile unsigned8  ivr;      /*  2 -  2 : Timer Interrupt Vector Register */
+  volatile unsigned8  pad1;     /*  3 -  3 : pad */ 
+  volatile unsigned32 cpr;      /*  4 -  7 : Timer Counter Preload Register */
+  volatile unsigned8  pad2[12]; /*  8 - 19 : pad */ 
+  volatile unsigned32 sr;       /* 20 - 23 : Timer Status Register */
+} timer_hw_t;
 
-#define Clock_driver_support_at_tick() \
+#define TIMER_BASE (timer_hw_t *)0x72001
-  Clock_driver_support_initialize_hardware()
 
-#define Clock_driver_support_shutdown_hardware()
+/* 8 microseconds per click, 125,000 per second */
+
+/* XXX should check that microseconds_per_tick is >= 8 */
+void Clock_driver_support_initialize_hardware()
+{
+  timer_hw_t *t = TIMER_BASE;
+
+  t->ivr = CLOCK_VECTOR;
+  t->cpr = rtems_configuration_get_microseconds_per_tick() / 8;
+  t->cr  = 0xA0;  /* initialize with timer disabled */
+  t->cr  = 0xA1;  /* enable timer */
+}
+
+void Clock_driver_support_at_tick()
+{
+  timer_hw_t *t = TIMER_BASE;
+  
+  t->sr  = 0xA0;  /* Negate timer interrupt request */
+}
+  
+
+void Clock_driver_support_shutdown_hardware()
+{
+  timer_hw_t *t = TIMER_BASE;
+
+  t->cr  = 0xA0;  /* initialize with timer disabled */
+}
 
 #include "../../../shared/clockdrv_shell.c"

c/src/lib/libbsp/m68k/sim68000/sim68000.setup

@@ -5,3 +5,4 @@ SIMULATOR {sim68000}
 COMMAND {AttachDevice 0 RAM {BaseAddress = 0 Size = 40000}}
 COMMAND {AttachDevice 0 RAM {BaseAddress = 40000 Size = 20000}}
 COMMAND {AttachDevice 0 M68681 {BaseAddress = 71001 OffsetToFirstRegister = 0 OffsetBetweenRegisters = 2 InterruptLevel = 4 PortAStandardInputOutputFlag = 0 PortBStandardInputOutputFlag = 0 PortACommand = xterm -T "M68681 Port A" -132 -fn fixed -e /usr3/tmp/bsvc-2.1/bin/xtermpipe PortBCommand = }}
+COMMAND {AttachDevice 0 Timer {BaseAddress = 72001 IRQ = 5}}