/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Copyright 2015, Cyril Bur, IBM Corp.
*/
#include "basic_asm.h"
#include "vsx_asm.h"
#long check_vsx(vector int *r3);
#This function wraps storeing VSX regs to the end of an array and a
#call to a comparison function in C which boils down to a memcmp()
FUNC_START(check_vsx)
PUSH_BASIC_STACK(32)
std r3,STACK_FRAME_PARAM(0)(sp)
addi r3, r3, 16 * 12 #Second half of array
bl store_vsx
ld r3,STACK_FRAME_PARAM(0)(sp)
bl vsx_memcmp
POP_BASIC_STACK(32)
blr
FUNC_END(check_vsx)
# int preempt_vmx(vector int *varray, int *threads_starting,
# int *running);
# On starting will (atomically) decrement threads_starting as a signal
# that the VMX have been loaded with varray. Will proceed to check the
# validity of the VMX registers while running is not zero.
FUNC_START(preempt_vsx)
PUSH_BASIC_STACK(512)
std r3,STACK_FRAME_PARAM(0)(sp) # vector int *varray
std r4,STACK_FRAME_PARAM(1)(sp) # int *threads_starting
std r5,STACK_FRAME_PARAM(2)(sp) # int *running
bl load_vsx
nop
sync
# Atomic DEC
ld r3,STACK_FRAME_PARAM(1)(sp)
1: lwarx r4,0,r3
addi r4,r4,-1
stwcx. r4,0,r3
bne- 1b
2: ld r3,STACK_FRAME_PARAM(0)(sp)
bl check_vsx
nop
cmpdi r3,0
bne 3f
ld r4,STACK_FRAME_PARAM(2)(sp)
ld r5,0(r4)
cmpwi r5,0
bne 2b
3: POP_BASIC_STACK(512)
blr
FUNC_END(preempt_vsx)