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Diffstat (limited to 'trunk/src/emu/cpu/psx/rcnt.c')
-rw-r--r--trunk/src/emu/cpu/psx/rcnt.c237
1 files changed, 237 insertions, 0 deletions
diff --git a/trunk/src/emu/cpu/psx/rcnt.c b/trunk/src/emu/cpu/psx/rcnt.c
new file mode 100644
index 00000000000..779943b346b
--- /dev/null
+++ b/trunk/src/emu/cpu/psx/rcnt.c
@@ -0,0 +1,237 @@
+/*
+ * PlayStation Root Counter emulator
+ *
+ * Copyright 2003-2011 smf
+ *
+ */
+
+#include "rcnt.h"
+#include "includes/psx.h"
+
+#define VERBOSE_LEVEL ( 0 )
+
+INLINE void ATTR_PRINTF(3,4) verboselog( running_machine& machine, int n_level, const char *s_fmt, ... )
+{
+ if( VERBOSE_LEVEL >= n_level )
+ {
+ va_list v;
+ char buf[ 32768 ];
+ va_start( v, s_fmt );
+ vsprintf( buf, s_fmt, v );
+ va_end( v );
+ logerror( "%s: %s", machine.describe_context(), buf );
+ }
+}
+
+const device_type PSX_RCNT = &device_creator<psxrcnt_device>;
+
+psxrcnt_device::psxrcnt_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+ : device_t(mconfig, PSX_RCNT, "PSX RCNT", tag, owner, clock)
+{
+}
+
+void psxrcnt_device::device_reset()
+{
+}
+
+void psxrcnt_device::device_post_load()
+{
+ int n;
+ for( n = 0; n < 3; n++ )
+ {
+ root_timer_adjust( n );
+ }
+}
+
+void psxrcnt_device::device_start()
+{
+ int n;
+
+ for( n = 0; n < 3; n++ )
+ {
+ root_counter[ n ].timer = machine().scheduler().timer_alloc( timer_expired_delegate( FUNC( psxrcnt_device::root_finished ), this ) );
+ state_save_register_item( machine(), "psxroot", NULL, n, root_counter[ n ].n_count );
+ state_save_register_item( machine(), "psxroot", NULL, n, root_counter[ n ].n_mode );
+ state_save_register_item( machine(), "psxroot", NULL, n, root_counter[ n ].n_target );
+ state_save_register_item( machine(), "psxroot", NULL, n, root_counter[ n ].n_start );
+ }
+}
+
+WRITE32_MEMBER( psxrcnt_device::write )
+{
+ int n_counter = offset / 4;
+ psx_root *root = &root_counter[ n_counter ];
+
+ verboselog( machine(), 1, "psx_counter_w ( %08x, %08x, %08x )\n", offset, data, mem_mask );
+
+ switch( offset % 4 )
+ {
+ case 0:
+ root->n_count = data;
+ root->n_start = gettotalcycles();
+ break;
+ case 1:
+ root->n_count = root_current( n_counter );
+ root->n_start = gettotalcycles();
+
+ if( ( data & PSX_RC_RESET ) != 0 )
+ {
+ data &= ~( PSX_RC_RESET | PSX_RC_STOP );
+ root->n_count = 0;
+ }
+
+ root->n_mode = data;
+
+#if 0
+ if( ( data & 0xfca6 ) != 0 ||
+ ( ( data & 0x0100 ) != 0 && n_counter != 0 && n_counter != 1 ) ||
+ ( ( data & 0x0200 ) != 0 && n_counter != 2 ) )
+ {
+ mame_printf_debug( "mode %d 0x%04x\n", n_counter, data & 0xfca6 );
+ }
+#endif
+ break;
+ case 2:
+ root->n_target = data;
+ break;
+ default:
+ verboselog( machine(), 0, "psx_counter_w( %08x, %08x, %08x ) unknown register\n", offset, mem_mask, data );
+ return;
+ }
+
+ root_timer_adjust( n_counter );
+}
+
+READ32_MEMBER( psxrcnt_device::read )
+{
+ int n_counter = offset / 4;
+ psx_root *root = &root_counter[ n_counter ];
+ UINT32 data;
+
+ switch( offset % 4 )
+ {
+ case 0:
+ data = root_current( n_counter );
+ break;
+ case 1:
+ data = root->n_mode;
+ break;
+ case 2:
+ data = root->n_target;
+ break;
+ default:
+ verboselog( machine(), 0, "psx_counter_r( %08x, %08x ) unknown register\n", offset, mem_mask );
+ return 0;
+ }
+ verboselog( machine(), 1, "psx_counter_r ( %08x, %08x ) %08x\n", offset, mem_mask, data );
+ return data;
+}
+
+UINT64 psxrcnt_device::gettotalcycles( void )
+{
+ /* TODO: should return the start of the current tick. */
+ return machine().firstcpu->total_cycles() * 2;
+}
+
+int psxrcnt_device::root_divider( int n_counter )
+{
+ psx_root *root = &root_counter[ n_counter ];
+
+ if( n_counter == 0 && ( root->n_mode & PSX_RC_CLC ) != 0 )
+ {
+ /* TODO: pixel clock, probably based on resolution */
+ return 5;
+ }
+ else if( n_counter == 1 && ( root->n_mode & PSX_RC_CLC ) != 0 )
+ {
+ return 2150;
+ }
+ else if( n_counter == 2 && ( root->n_mode & PSX_RC_DIV ) != 0 )
+ {
+ return 8;
+ }
+ return 1;
+}
+
+UINT16 psxrcnt_device::root_current( int n_counter )
+{
+ psx_root *root = &root_counter[ n_counter ];
+
+ if( ( root->n_mode & PSX_RC_STOP ) != 0 )
+ {
+ return root->n_count;
+ }
+ else
+ {
+ UINT64 n_current;
+ n_current = gettotalcycles() - root->n_start;
+ n_current /= root_divider( n_counter );
+ n_current += root->n_count;
+ if( n_current > 0xffff )
+ {
+ /* TODO: use timer for wrap on 0x10000. */
+ root->n_count = n_current;
+ root->n_start = gettotalcycles();
+ }
+ return n_current;
+ }
+}
+
+int psxrcnt_device::root_target( int n_counter )
+{
+ psx_root *root = &root_counter[ n_counter ];
+
+ if( ( root->n_mode & PSX_RC_COUNTTARGET ) != 0 ||
+ ( root->n_mode & PSX_RC_IRQTARGET ) != 0 )
+ {
+ return root->n_target;
+ }
+ return 0x10000;
+}
+
+void psxrcnt_device::root_timer_adjust( int n_counter )
+{
+ psx_root *root = &root_counter[ n_counter ];
+
+ if( ( root->n_mode & PSX_RC_STOP ) != 0 )
+ {
+ root->timer->adjust( attotime::never, n_counter);
+ }
+ else
+ {
+ int n_duration;
+
+ n_duration = root_target( n_counter ) - root_current( n_counter );
+ if( n_duration < 1 )
+ {
+ n_duration += 0x10000;
+ }
+
+ n_duration *= root_divider( n_counter );
+
+ root->timer->adjust( attotime::from_hz(33868800) * n_duration, n_counter);
+ }
+}
+
+void psxrcnt_device::root_finished( void *ptr, int param )
+{
+ int n_counter = param;
+ psx_root *root = &root_counter[ n_counter ];
+
+ verboselog( machine(), 2, "root_finished( %d ) %04x\n", n_counter, root_current( n_counter ) );
+ //if( ( root->n_mode & PSX_RC_COUNTTARGET ) != 0 )
+ {
+ /* TODO: wrap should be handled differently as PSX_RC_COUNTTARGET & PSX_RC_IRQTARGET don't have to be the same. */
+ root->n_count = 0;
+ root->n_start = gettotalcycles();
+ }
+ if( ( root->n_mode & PSX_RC_REPEAT ) != 0 )
+ {
+ root_timer_adjust( n_counter );
+ }
+ if( ( root->n_mode & PSX_RC_IRQOVERFLOW ) != 0 ||
+ ( root->n_mode & PSX_RC_IRQTARGET ) != 0 )
+ {
+ psx_irq_set( machine(), PSX_IRQ_ROOTCOUNTER0 << n_counter );
+ }
+}