1 files changed, 310 insertions, 0 deletions
diff --git a/arch/m68k/mac/macboing.c b/arch/m68k/mac/macboing.c
new file mode 100644
index 000000000..388780797
--- /dev/null
+++ b/arch/m68k/mac/macboing.c
@@ -0,0 +1,310 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *	Mac bong noise generator. Note - we ought to put a boingy noise
+ *	here 8)
+ *
+ *	----------------------------------------------------------------------
+ *	16.11.98:
+ *	rewrote some functions, added support for Enhanced ASC (Quadras)
+ *	after the NetBSD asc.c console bell patch by Colin Wood/Frederick Bruck
+ *	Juergen Mellinger (juergen.mellinger@t-online.de)
+ */
+
+#include <linux/sched.h>
+#include <linux/timer.h>
+
+#include <asm/macintosh.h>
+#include <asm/mac_asc.h>
+
+static int mac_asc_inited;
+/*
+ * dumb triangular wave table
+ */
+static __u8 mac_asc_wave_tab[ 0x800 ];
+
+/*
+ * Alan's original sine table; needs interpolating to 0x800
+ * (hint: interpolate or hardwire [0 -> Pi/2[, it's symmetric)
+ */
+static const signed char sine_data[] = {
+	0,  39,  75,  103,  121,  127,  121,  103,  75,  39,
+	0, -39, -75, -103, -121, -127, -121, -103, -75, -39
+};
+
+/*
+ * where the ASC hides ...
+ */
+static volatile __u8* mac_asc_regs = ( void* )0x50F14000;
+
+/*
+ * sample rate; is this a good default value?
+ */
+static unsigned long mac_asc_samplespersec = 11050;
+static int mac_bell_duration;
+static unsigned long mac_bell_phase; /* 0..2*Pi -> 0..0x800 (wavetable size) */
+static unsigned long mac_bell_phasepersample;
+
+/*
+ * some function protos
+ */
+static void mac_init_asc( void );
+static void mac_nosound(struct timer_list *);
+static void mac_quadra_start_bell( unsigned int, unsigned int, unsigned int );
+static void mac_quadra_ring_bell(struct timer_list *);
+static void mac_av_start_bell( unsigned int, unsigned int, unsigned int );
+static void ( *mac_special_bell )( unsigned int, unsigned int, unsigned int );
+
+/*
+ * our timer to start/continue/stop the bell
+ */
+static DEFINE_TIMER(mac_sound_timer, mac_nosound);
+
+/*
+ * Sort of initialize the sound chip (called from mac_mksound on the first
+ * beep).
+ */
+static void mac_init_asc( void )
+{
+	int i;
+
+	/*
+	 * do some machine specific initialization
+	 * BTW:
+	 * the NetBSD Quadra patch identifies the Enhanced Apple Sound Chip via
+	 *	mac_asc_regs[ 0x800 ] & 0xF0 != 0
+	 * this makes no sense here, because we have to set the default sample
+	 * rate anyway if we want correct frequencies
+	 */
+	switch ( macintosh_config->ident )
+	{
+		case MAC_MODEL_IIFX:
+			/*
+			 * The IIfx is always special ...
+			 */
+			mac_asc_regs = ( void* )0x50010000;
+			break;
+			/*
+			 * not sure about how correct this list is
+			 * machines with the EASC enhanced apple sound chip
+			 */
+		case MAC_MODEL_Q630:
+		case MAC_MODEL_P475:
+			mac_special_bell = mac_quadra_start_bell;
+			mac_asc_samplespersec = 22150;
+			break;
+		case MAC_MODEL_C660:
+		case MAC_MODEL_Q840:
+			/*
+			 * The Quadra 660AV and 840AV use the "Singer" custom ASIC for sound I/O.
+			 * It appears to be similar to the "AWACS" custom ASIC in the Power Mac
+			 * [678]100.  Because Singer and AWACS may have a similar hardware
+			 * interface, this would imply that the code in drivers/sound/dmasound.c
+			 * for AWACS could be used as a basis for Singer support.  All we have to
+			 * do is figure out how to do DMA on the 660AV/840AV through the PSC and
+			 * figure out where the Singer hardware sits in memory. (I'd look in the
+			 * vicinity of the AWACS location in a Power Mac [678]100 first, or the
+			 * current location of the Apple Sound Chip--ASC--in other Macs.)  The
+			 * Power Mac [678]100 info can be found in MkLinux Mach kernel sources.
+			 *
+			 * Quoted from Apple's Tech Info Library, article number 16405:
+			 *   "Among desktop Macintosh computers, only the 660AV, 840AV, and Power
+			 *   Macintosh models have 16-bit audio input and output capability
+			 *   because of the AT&T DSP3210 hardware circuitry and the 16-bit Singer
+			 *   codec circuitry in the AVs.  The Audio Waveform Amplifier and
+			 *   Converter (AWAC) chip in the Power Macintosh performs the same
+			 *   16-bit I/O functionality.  The PowerBook 500 series computers
+			 *   support 16-bit stereo output, but only mono input."
+			 *
+			 *   Technical Information Library (TIL) article number 16405. 
+			 *   http://support.apple.com/kb/TA32601 
+			 *
+			 * --David Kilzer
+			 */
+			mac_special_bell = mac_av_start_bell;
+			break;
+		case MAC_MODEL_Q650:
+		case MAC_MODEL_Q700:
+		case MAC_MODEL_Q800:
+		case MAC_MODEL_Q900:
+		case MAC_MODEL_Q950:
+			/*
+			 * Currently not implemented!
+			 */
+			mac_special_bell = NULL;
+			break;
+		default:
+			/*
+			 * Every switch needs a default
+			 */
+			mac_special_bell = NULL;
+			break;
+	}
+
+	/*
+	 * init the wave table with a simple triangular wave
+	 * A sine wave would sure be nicer here ...
+	 */
+	for ( i = 0; i < 0x400; i++ )
+	{
+		mac_asc_wave_tab[ i ] = i / 4;
+		mac_asc_wave_tab[ i + 0x400 ] = 0xFF - i / 4;
+	}
+	mac_asc_inited = 1;
+}
+
+/*
+ * Called to make noise; current single entry to the boing driver.
+ * Does the job for simple ASC, calls other routines else.
+ * XXX Fixme:
+ * Should be split into asc_mksound, easc_mksound, av_mksound and
+ * function pointer set in mac_init_asc which would be called at
+ * init time.
+ * _This_ is rather ugly ...
+ */
+void mac_mksound( unsigned int freq, unsigned int length )
+{
+	__u32 cfreq = ( freq << 5 ) / 468;
+	unsigned long flags;
+	int i;
+
+	if ( mac_special_bell == NULL )
+	{
+		/* Do nothing */
+		return;
+	}
+
+	if ( !mac_asc_inited )
+		mac_init_asc();
+
+	if ( mac_special_bell )
+	{
+		mac_special_bell( freq, length, 128 );
+		return;
+	}
+
+	if ( freq < 20 || freq > 20000 || length == 0 )
+	{
+		mac_nosound( 0 );
+		return;
+	}
+
+	local_irq_save(flags);
+
+	del_timer( &mac_sound_timer );
+
+	for ( i = 0; i < 0x800; i++ )
+		mac_asc_regs[ i ] = 0;
+	for ( i = 0; i < 0x800; i++ )
+		mac_asc_regs[ i ] = mac_asc_wave_tab[ i ];
+
+	for ( i = 0; i < 8; i++ )
+		*( __u32* )( ( __u32 )mac_asc_regs + ASC_CONTROL + 0x814 + 8 * i ) = cfreq;
+
+	mac_asc_regs[ 0x807 ] = 0;
+	mac_asc_regs[ ASC_VOLUME ] = 128;
+	mac_asc_regs[ 0x805 ] = 0;
+	mac_asc_regs[ 0x80F ] = 0;
+	mac_asc_regs[ ASC_MODE ] = ASC_MODE_SAMPLE;
+	mac_asc_regs[ ASC_ENABLE ] = ASC_ENABLE_SAMPLE;
+
+	mac_sound_timer.expires = jiffies + length;
+	add_timer( &mac_sound_timer );
+
+	local_irq_restore(flags);
+}
+
+/*
+ * regular ASC: stop whining ..
+ */
+static void mac_nosound(struct timer_list *unused)
+{
+	mac_asc_regs[ ASC_ENABLE ] = 0;
+}
+
+/*
+ * EASC entry; init EASC, don't load wavetable, schedule 'start whining'.
+ */
+static void mac_quadra_start_bell( unsigned int freq, unsigned int length, unsigned int volume )
+{
+	unsigned long flags;
+
+	/* if the bell is already ringing, ring longer */
+	if ( mac_bell_duration > 0 )
+	{
+		mac_bell_duration += length;
+		return;
+	}
+
+	mac_bell_duration = length;
+	mac_bell_phase = 0;
+	mac_bell_phasepersample = ( freq * sizeof( mac_asc_wave_tab ) ) / mac_asc_samplespersec;
+	/* this is reasonably big for small frequencies */
+
+	local_irq_save(flags);
+
+	/* set the volume */
+	mac_asc_regs[ 0x806 ] = volume;
+
+	/* set up the ASC registers */
+	if ( mac_asc_regs[ 0x801 ] != 1 )
+	{
+		/* select mono mode */
+		mac_asc_regs[ 0x807 ] = 0;
+		/* select sampled sound mode */
+		mac_asc_regs[ 0x802 ] = 0;
+		/* ??? */
+		mac_asc_regs[ 0x801 ] = 1;
+		mac_asc_regs[ 0x803 ] |= 0x80;
+		mac_asc_regs[ 0x803 ] &= 0x7F;
+	}
+
+	mac_sound_timer.function = mac_quadra_ring_bell;
+	mac_sound_timer.expires = jiffies + 1;
+	add_timer( &mac_sound_timer );
+
+	local_irq_restore(flags);
+}
+
+/*
+ * EASC 'start/continue whining'; I'm not sure why the above function didn't
+ * already load the wave table, or at least call this one...
+ * This piece keeps reloading the wave table until done.
+ */
+static void mac_quadra_ring_bell(struct timer_list *unused)
+{
+	int	i, count = mac_asc_samplespersec / HZ;
+	unsigned long flags;
+
+	/*
+	 * we neither want a sound buffer overflow nor underflow, so we need to match
+	 * the number of samples per timer interrupt as exactly as possible.
+	 * using the asc interrupt will give better results in the future
+	 * ...and the possibility to use a real sample (a boingy noise, maybe...)
+	 */
+
+	local_irq_save(flags);
+
+	del_timer( &mac_sound_timer );
+
+	if ( mac_bell_duration-- > 0 )
+	{
+		for ( i = 0; i < count; i++ )
+		{
+			mac_bell_phase += mac_bell_phasepersample;
+			mac_asc_regs[ 0 ] = mac_asc_wave_tab[ mac_bell_phase & ( sizeof( mac_asc_wave_tab ) - 1 ) ];
+		}
+		mac_sound_timer.expires = jiffies + 1;
+		add_timer( &mac_sound_timer );
+	}
+	else
+		mac_asc_regs[ 0x801 ] = 0;
+
+	local_irq_restore(flags);
+}
+
+/*
+ * AV code - please fill in.
+ */
+static void mac_av_start_bell( unsigned int freq, unsigned int length, unsigned int volume )
+{
+}