rockbox/firmware/asm/sh/thread.c
Thomas Martitz 991ae1e395 Create fimrware/asm directory for assembly optimized stuff.
This dir is suitable for stuff that doesn't fit the target tree, e.g. because
it also builds on hosted or otherwise. It also has a generic subfolder for
fallback C implementations so that not all archs need to provide asm files.

SOURCES should only contain "foo.c" where foo.c includes the specific
<arch>/foo.c files from the subdirs using the preprocessor. This way automatic
selection of asm versions or generic C verion is possible.

For the start, the thread support files are moved, since ASM threads can
be used on hosted platforms as well. Since core_sleep() remains platform
specific it's moved to the corresponding system.h headers.

Change-Id: Iebff272f3407a6eaafeb7656ceb0ae9eca3f7cb9
2012-01-22 18:46:44 +01:00

96 lines
3.6 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2002 by Ulf Ralberg
*
* SH 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)
{
/* r8 = context */
asm volatile (
"_start_thread: \n" /* Start here - no naked attribute */
"mov.l @(4, r8), r0 \n" /* Fetch thread function pointer */
"mov.l @(28, r8), r15 \n" /* Set initial sp */
"mov #0, r1 \n" /* Start the thread */
"jsr @r0 \n"
"mov.l r1, @(36, r8) \n" /* Clear start address */
);
thread_exit();
}
/* Place context pointer in r8 slot, function pointer in r9 slot, and
* start_thread pointer in context_start */
#define THREAD_STARTUP_INIT(core, thread, function) \
({ (thread)->context.r[0] = (uint32_t)&(thread)->context, \
(thread)->context.r[1] = (uint32_t)(function), \
(thread)->context.start = (uint32_t)start_thread; })
/*---------------------------------------------------------------------------
* Store non-volatile context.
*---------------------------------------------------------------------------
*/
static inline void store_context(void* addr)
{
asm volatile (
"add #36, %0 \n" /* Start at last reg. By the time routine */
"sts.l pr, @-%0 \n" /* is done, %0 will have the original value */
"mov.l r15,@-%0 \n"
"mov.l r14,@-%0 \n"
"mov.l r13,@-%0 \n"
"mov.l r12,@-%0 \n"
"mov.l r11,@-%0 \n"
"mov.l r10,@-%0 \n"
"mov.l r9, @-%0 \n"
"mov.l r8, @-%0 \n"
: : "r" (addr)
);
}
/*---------------------------------------------------------------------------
* Load non-volatile context.
*---------------------------------------------------------------------------
*/
static inline void load_context(const void* addr)
{
asm volatile (
"mov.l @(36, %0), r0 \n" /* Get start address */
"tst r0, r0 \n"
"bt .running \n" /* NULL -> already running */
"jmp @r0 \n" /* r8 = context */
".running: \n"
"mov.l @%0+, r8 \n" /* Executes in delay slot and outside it */
"mov.l @%0+, r9 \n"
"mov.l @%0+, r10 \n"
"mov.l @%0+, r11 \n"
"mov.l @%0+, r12 \n"
"mov.l @%0+, r13 \n"
"mov.l @%0+, r14 \n"
"mov.l @%0+, r15 \n"
"lds.l @%0+, pr \n"
: : "r" (addr) : "r0" /* only! */
);
}