rockbox/firmware/asm/mips/thread-mips32.c
Marcin Bukat 71dc1a789a Fix MIPS threading code to compile with older compiler
Official rockbox mips gcc is old and doesn't support
symbolic register names in inline assembly

Change-Id: If67230d06e28ccf31b0f8f8e1b622275fed3f6ff
2018-06-12 12:41:03 +02:00

112 lines
4.3 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2008 by Maurus Cuelenaere
*
* 32-bit MIPS 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
*---------------------------------------------------------------------------
*/
static void USED_ATTR start_thread(void *addr)
{
asm volatile (
".set noreorder \n"
".set noat \n"
"lw $25, 4(%0) \n" /* Fetch thread function pointer ($25 = t9) */
"lw $25, 40(%0) \n" /* Set initial sp(=$29) */
"jalr $25 \n" /* Start the thread */
"sw $0, 48(%0) \n" /* Clear start address */
".set at \n"
".set reorder \n"
: : "r" (addr) : "$25"
);
thread_exit();
}
/* Place context pointer in s0 slot, function pointer in s1 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 (
".set noreorder \n"
".set noat \n"
"sw $16, 0(%0) \n" /* s0 */
"sw $17, 4(%0) \n" /* s1 */
"sw $18, 8(%0) \n" /* s2 */
"sw $19, 12(%0) \n" /* s3 */
"sw $20, 16(%0) \n" /* s4 */
"sw $21, 20(%0) \n" /* s5 */
"sw $22, 24(%0) \n" /* s6 */
"sw $23, 28(%0) \n" /* s7 */
"sw $28, 32(%0) \n" /* gp */
"sw $30, 36(%0) \n" /* fp */
"sw $29, 40(%0) \n" /* sp */
"sw $31, 44(%0) \n" /* ra */
".set at \n"
".set reorder \n"
: : "r" (addr)
);
}
/*---------------------------------------------------------------------------
* Load non-volatile context.
*---------------------------------------------------------------------------
*/
static inline void load_context(const void* addr)
{
asm volatile (
".set noat \n"
".set noreorder \n"
"lw $25, 48(%0) \n" /* Get start address (t9 = $25) */
"beqz $25, running \n" /* NULL -> already running */
"nop \n"
"jr $25 \n"
"move $4, %0 \n" /* a0 = context branch delay slot anyway */
"running: \n"
"lw $16, 0(%0) \n" /* s0 */
"lw $17, 4(%0) \n" /* s1 */
"lw $18, 8(%0) \n" /* s2 */
"lw $19, 12(%0) \n" /* s3 */
"lw $20, 16(%0) \n" /* s4 */
"lw $21, 20(%0) \n" /* s5 */
"lw $22, 24(%0) \n" /* s6 */
"lw $23, 28(%0) \n" /* s7 */
"lw $28, 32(%0) \n" /* gp */
"lw $30, 36(%0) \n" /* fp */
"lw $29, 40(%0) \n" /* sp */
"lw $31, 44(%0) \n" /* ra */
".set at \n"
".set reorder \n"
: : "r" (addr) : "$25"
);
}