Split CPU-optimized beep code into the firmware/asm tree.

For now due to current lack of an apps/asm, place the ASM/generic code in the
firmware/asm directory.

Additionally, make generic beep code more generic.

Change-Id: I4a69b6ffcbb97d9e6dfde2209c5a118de19e5638

4 files changed, 151 insertions, 61 deletions

diff --git a/apps/beep.c b/apps/beep.c
index a6244d9..79c7f1d 100644
--- a/apps/beep.c
+++ b/apps/beep.c
@@ -26,71 +26,22 @@
 #include "pcm_mixer.h"
 #include "misc.h"
 
-static int32_t beep_phase;      /* Phase of square wave generator */
+/** Beep generation, CPU optimized **/
+#include "../firmware/asm/beep.c"
+
+static uint32_t beep_phase;     /* Phase of square wave generator */
 static uint32_t beep_step;      /* Step of square wave generator on each sample */
+#ifdef BEEP_GENERIC
+static int16_t  beep_amplitude; /* Amplitude of square wave generator */
+#else
+/* Optimized routines do XOR with phase sign bit in both channels at once */
 static uint32_t beep_amplitude; /* Amplitude of square wave generator */
+#endif
 static int beep_count;          /* Number of samples remaining to generate */
 
 /* Reserve enough static space for keyclick to fit */
 #define BEEP_BUF_COUNT (NATIVE_FREQUENCY / 1000 * KEYCLICK_DURATION)
-static uint32_t beep_buf[BEEP_BUF_COUNT] IBSS_ATTR;
-
-/* Actually output samples into beep_buf */
-#if defined(CPU_ARM)
-static FORCE_INLINE void beep_generate(int count)
-{
-    uint32_t *out = beep_buf;
-    uint32_t s;
-
-    asm volatile (
-    "1:                            \n"
-        "eor   %3, %5, %1, asr #31 \n"
-        "subs  %2, %2, #1          \n"
-        "str   %3, [%0], #4        \n"
-        "add   %1, %1, %4          \n"
-        "bgt   1b                  \n"
-        : "+r"(out), "+r"(beep_phase), "+r"(count),
-          "=&r"(s)
-        : "r"(beep_step), "r"(beep_amplitude));
-}
-#elif defined (CPU_COLDFIRE)
-static FORCE_INLINE void beep_generate(int count)
-{
-    uint32_t *out = beep_buf;
-    uint32_t s;
-
-    asm volatile (
-    "1:                   \n"
-        "move.l %1, %3    \n"
-        "add.l  %4, %1    \n"
-        "add.l  %3, %3    \n"
-        "subx.l %3, %3    \n"
-        "eor.l  %5, %3    \n"
-        "move.l %3, (%0)+ \n"
-        "subq.l #1, %2    \n"
-        "bgt.b  1b        \n"
-        : "+a"(out), "+d"(beep_phase), "+d"(count),
-          "=&d"(s)
-        : "r"(beep_step), "d"(beep_amplitude));
-}
-#else
-static FORCE_INLINE void beep_generate(int count)
-{
-    uint32_t *out = beep_buf;
-    uint32_t amplitude = beep_amplitude;
-    uint32_t step = beep_step;
-    int32_t phase = beep_phase;
-
-    do
-    {
-        *out++ = (phase >> 31) ^ amplitude;
-        phase += step;
-    }
-    while (--count > 0);
-
-    beep_phase = phase;
-}
-#endif
+static int16_t beep_buf[BEEP_BUF_COUNT*2] IBSS_ATTR __attribute__((aligned(4)));
 
 /* Callback to generate the beep frames - also don't want inlining of
    call below in beep_play */
@@ -104,8 +55,9 @@ beep_get_more(unsigned char **start, size_t *size)
         count = MIN(count, BEEP_BUF_COUNT);
         beep_count -= count;
         *start = (unsigned char *)beep_buf;
-        *size = count * sizeof(uint32_t);
-        beep_generate(count);
+        *size = count * 2 * sizeof (int16_t);
+        beep_generate((void *)beep_buf, count, &beep_phase,
+                      beep_step, beep_amplitude);
     }
 }
 
@@ -126,7 +78,13 @@ void beep_play(unsigned int frequency, unsigned int duration,
     beep_phase = 0;
     beep_step = 0xffffffffu / NATIVE_FREQUENCY * frequency;
     beep_count = NATIVE_FREQUENCY / 1000 * duration;
+
+#ifdef BEEP_GENERIC
+    beep_amplitude = amplitude;
+#else
+    /* Optimized routines do XOR with phase sign bit in both channels at once */
     beep_amplitude = amplitude | (amplitude << 16); /* Word:|AMP16|AMP16| */
+#endif
 
     /* If it fits - avoid cb overhead */
     unsigned char *start;
diff --git a/firmware/asm/arm/beep.c b/firmware/asm/arm/beep.c
new file mode 100644
index 0000000..f3c3e2e
--- /dev/null
+++ b/firmware/asm/arm/beep.c
@@ -0,0 +1,39 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (c) 2011 Michael Sevakis
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+/* Actually output samples into beep_buf */
+static FORCE_INLINE void beep_generate(uint32_t *out, int count,
+                                       int32_t *phase, uint32_t step,
+                                       uint32_t amplitude)
+{
+    uint32_t s;
+
+    asm volatile (
+    "1:                            \n"
+        "eor   %3, %5, %1, asr #31 \n"
+        "subs  %2, %2, #1          \n"
+        "str   %3, [%0], #4        \n"
+        "add   %1, %1, %4          \n"
+        "bgt   1b                  \n"
+        : "+r"(out), "+r"(*phase), "+r"(count),
+          "=&r"(s)
+        : "r"(step), "r"(amplitude));
+}
diff --git a/firmware/asm/beep.c b/firmware/asm/beep.c
new file mode 100644
index 0000000..0314e32
--- /dev/null
+++ b/firmware/asm/beep.c
@@ -0,0 +1,51 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (c) 2011 Michael Sevakis
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#if defined(CPU_ARM)
+#include "arm/beep.c"
+#elif defined (CPU_COLDFIRE)
+#include "m68k/beep.c"
+#else /* Generic */
+
+static FORCE_INLINE void beep_generate(int16_t *out, int count,
+                                       uint32_t *phase, uint32_t step,
+                                       int16_t amplitude)
+{
+    uint32_t ph = *phase;
+
+    do
+    {
+        int16_t amp = amplitude;
+
+        if (ph > UINT32_MAX / 2)
+            amp = -amp;
+
+        *out++ = amp;
+        *out++ = amp;
+
+        ph += step;
+    }
+    while (--count > 0);
+
+    *phase = ph;
+}
+
+#define BEEP_GENERIC
+#endif /* CPU_* */
diff --git a/firmware/asm/m68k/beep.c b/firmware/asm/m68k/beep.c
new file mode 100644
index 0000000..5461a4e
--- /dev/null
+++ b/firmware/asm/m68k/beep.c
@@ -0,0 +1,42 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (c) 2011 Michael Sevakis
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+/* Actually output samples into beep_buf */
+static FORCE_INLINE void beep_generate(uint32_t *out, int count,
+                                       int32_t *phase, uint32_t step,
+                                       uint32_t amplitude)
+{
+    uint32_t s;
+
+    asm volatile (
+    "1:                   \n"
+        "move.l %1, %3    \n"
+        "add.l  %4, %1    \n"
+        "add.l  %3, %3    \n"
+        "subx.l %3, %3    \n"
+        "eor.l  %5, %3    \n"
+        "move.l %3, (%0)+ \n"
+        "subq.l #1, %2    \n"
+        "bgt.b  1b        \n"
+        : "+a"(out), "+d"(*phase), "+d"(count),
+          "=&d"(s)
+        : "r"(step), "d"(amplitude));
+}