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-rw-r--r--firmware/asm/m68k/thread.c101
1 files changed, 101 insertions, 0 deletions
diff --git a/firmware/asm/m68k/thread.c b/firmware/asm/m68k/thread.c
new file mode 100644
index 0000000000..7df89001d7
--- /dev/null
+++ b/firmware/asm/m68k/thread.c
@@ -0,0 +1,101 @@
+/***************************************************************************
+ * __________ __ ___.
+ * Open \______ \ ____ ____ | | _\_ |__ _______ ___
+ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
+ * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
+ * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
+ * \/ \/ \/ \/ \/
+ * $Id$
+ *
+ * Copyright (C) 2004 by Linus Nielsen Feltzing
+ *
+ * Coldfire processor threading support
+ *
+ * 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.
+ *
+ ****************************************************************************/
+
+/*---------------------------------------------------------------------------
+ * Start the thread running and terminate it if it returns
+ *---------------------------------------------------------------------------
+ */
+void start_thread(void); /* Provide C access to ASM label */
+static void USED_ATTR __start_thread(void)
+{
+ /* a0=macsr, a1=context */
+ asm volatile (
+ "start_thread: \n" /* Start here - no naked attribute */
+ "move.l %a0, %macsr \n" /* Set initial mac status reg */
+ "lea.l 48(%a1), %a1 \n"
+ "move.l (%a1)+, %sp \n" /* Set initial stack */
+ "move.l (%a1), %a2 \n" /* Fetch thread function pointer */
+ "clr.l (%a1) \n" /* Mark thread running */
+ "jsr (%a2) \n" /* Call thread function */
+ );
+ thread_exit();
+}
+
+/* Set EMAC unit to fractional mode with saturation for each new thread,
+ * since that's what'll be the most useful for most things which the dsp
+ * will do. Codecs should still initialize their preferred modes
+ * explicitly. Context pointer is placed in d2 slot and start_thread
+ * pointer in d3 slot. thread function pointer is placed in context.start.
+ * See load_context for what happens when thread is initially going to
+ * run.
+ */
+#define THREAD_STARTUP_INIT(core, thread, function) \
+ ({ (thread)->context.macsr = EMAC_FRACTIONAL | EMAC_SATURATE, \
+ (thread)->context.d[0] = (uint32_t)&(thread)->context, \
+ (thread)->context.d[1] = (uint32_t)start_thread, \
+ (thread)->context.start = (uint32_t)(function); })
+
+/*---------------------------------------------------------------------------
+ * Store non-volatile context.
+ *---------------------------------------------------------------------------
+ */
+static inline void store_context(void* addr)
+{
+ asm volatile (
+ "move.l %%macsr,%%d0 \n"
+ "movem.l %%d0/%%d2-%%d7/%%a2-%%a7,(%0) \n"
+ : : "a" (addr) : "d0" /* only! */
+ );
+}
+
+/*---------------------------------------------------------------------------
+ * Load non-volatile context.
+ *---------------------------------------------------------------------------
+ */
+static inline void load_context(const void* addr)
+{
+ asm volatile (
+ "move.l 52(%0), %%d0 \n" /* Get start address */
+ "beq.b 1f \n" /* NULL -> already running */
+ "movem.l (%0), %%a0-%%a2 \n" /* a0=macsr, a1=context, a2=start_thread */
+ "jmp (%%a2) \n" /* Start the thread */
+ "1: \n"
+ "movem.l (%0), %%d0/%%d2-%%d7/%%a2-%%a7 \n" /* Load context */
+ "move.l %%d0, %%macsr \n"
+ : : "a" (addr) : "d0" /* only! */
+ );
+}
+
+/*---------------------------------------------------------------------------
+ * Call this from asm to make sure the sp is pointing to the
+ * correct place before the context is saved.
+ *---------------------------------------------------------------------------
+ */
+static inline void _profile_thread_stopped(int current_thread)
+{
+ asm volatile ("move.l %[id], -(%%sp)\n\t"
+ "jsr profile_thread_stopped\n\t"
+ "addq.l #4, %%sp\n\t"
+ :: [id] "r" (current_thread)
+ : "cc", "memory");
+}