/*
* Copyright (c) 2018 embedded brains GmbH
*
* Copyright (c) 2015 University of York.
* Hesham ALmatary <hesham@alumni.york.ac.uk>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <rtems/asm.h>
#include <rtems/score/percpu.h>
.section .text, "ax", @progbits
.align 2
PUBLIC(_CPU_Context_switch)
PUBLIC(_CPU_Context_switch_no_return)
PUBLIC(_CPU_Context_restore)
SYM(_CPU_Context_switch):
SYM(_CPU_Context_switch_no_return):
GET_SELF_CPU_CONTROL a2
lw a3, PER_CPU_ISR_DISPATCH_DISABLE(a2)
#if __riscv_flen > 0
frcsr a4
#endif
SREG ra, RISCV_CONTEXT_RA(a0)
SREG sp, RISCV_CONTEXT_SP(a0)
SREG s0, RISCV_CONTEXT_S0(a0)
SREG s1, RISCV_CONTEXT_S1(a0)
SREG s2, RISCV_CONTEXT_S2(a0)
SREG s3, RISCV_CONTEXT_S3(a0)
SREG s4, RISCV_CONTEXT_S4(a0)
SREG s5, RISCV_CONTEXT_S5(a0)
SREG s6, RISCV_CONTEXT_S6(a0)
SREG s7, RISCV_CONTEXT_S7(a0)
SREG s8, RISCV_CONTEXT_S8(a0)
SREG s9, RISCV_CONTEXT_S9(a0)
SREG s10, RISCV_CONTEXT_S10(a0)
SREG s11, RISCV_CONTEXT_S11(a0)
#if __riscv_flen > 0
sw a4, RISCV_CONTEXT_FCSR(a0)
FSREG fs0, RISCV_CONTEXT_FS0(a0)
FSREG fs1, RISCV_CONTEXT_FS1(a0)
FSREG fs2, RISCV_CONTEXT_FS2(a0)
FSREG fs3, RISCV_CONTEXT_FS3(a0)
FSREG fs4, RISCV_CONTEXT_FS4(a0)
FSREG fs5, RISCV_CONTEXT_FS5(a0)
FSREG fs6, RISCV_CONTEXT_FS6(a0)
FSREG fs7, RISCV_CONTEXT_FS7(a0)
FSREG fs8, RISCV_CONTEXT_FS8(a0)
FSREG fs9, RISCV_CONTEXT_FS9(a0)
FSREG fs10, RISCV_CONTEXT_FS10(a0)
FSREG fs11, RISCV_CONTEXT_FS11(a0)
#endif
sw a3, RISCV_CONTEXT_ISR_DISPATCH_DISABLE(a0)
#ifdef RTEMS_SMP
/*
* The executing thread no longer executes on this processor. Switch
* the stack to the temporary interrupt stack of this processor. Mark
* the context of the executing thread as not executing.
*/
addi sp, a2, PER_CPU_INTERRUPT_FRAME_AREA + CPU_INTERRUPT_FRAME_SIZE
amoswap.w.rl zero, zero, RISCV_CONTEXT_IS_EXECUTING(a0)
.Ltry_update_is_executing:
/* Try to update the is executing indicator of the heir context */
li a3, 1
amoswap.w.aq a3, a3, RISCV_CONTEXT_IS_EXECUTING(a1)
bnez a3, .Lcheck_is_executing
#endif
.Lrestore:
lw a3, RISCV_CONTEXT_ISR_DISPATCH_DISABLE(a1)
LREG ra, RISCV_CONTEXT_RA(a1)
LREG sp, RISCV_CONTEXT_SP(a1)
LREG tp, RISCV_CONTEXT_TP(a1)
LREG s0, RISCV_CONTEXT_S0(a1)
LREG s1, RISCV_CONTEXT_S1(a1)
LREG s2, RISCV_CONTEXT_S2(a1)
LREG s3, RISCV_CONTEXT_S3(a1)
LREG s4, RISCV_CONTEXT_S4(a1)
LREG s5, RISCV_CONTEXT_S5(a1)
LREG s6, RISCV_CONTEXT_S6(a1)
LREG s7, RISCV_CONTEXT_S7(a1)
LREG s8, RISCV_CONTEXT_S8(a1)
LREG s9, RISCV_CONTEXT_S9(a1)
LREG s10, RISCV_CONTEXT_S10(a1)
LREG s11, RISCV_CONTEXT_S11(a1)
#if __riscv_flen > 0
lw a4, RISCV_CONTEXT_FCSR(a1)
FLREG fs0, RISCV_CONTEXT_FS0(a1)
FLREG fs1, RISCV_CONTEXT_FS1(a1)
FLREG fs2, RISCV_CONTEXT_FS2(a1)
FLREG fs3, RISCV_CONTEXT_FS3(a1)
FLREG fs4, RISCV_CONTEXT_FS4(a1)
FLREG fs5, RISCV_CONTEXT_FS5(a1)
FLREG fs6, RISCV_CONTEXT_FS6(a1)
FLREG fs7, RISCV_CONTEXT_FS7(a1)
FLREG fs8, RISCV_CONTEXT_FS8(a1)
FLREG fs9, RISCV_CONTEXT_FS9(a1)
FLREG fs10, RISCV_CONTEXT_FS10(a1)
FLREG fs11, RISCV_CONTEXT_FS11(a1)
fscsr a4
#endif
sw a3, PER_CPU_ISR_DISPATCH_DISABLE(a2)
CLEAR_RESERVATIONS a2
ret
SYM(_CPU_Context_restore):
mv a1, a0
GET_SELF_CPU_CONTROL a2
j .Lrestore
#ifdef RTEMS_SMP
.Lcheck_is_executing:
/* Check the is executing indicator of the heir context */
lw a3, RISCV_CONTEXT_IS_EXECUTING(a1)
beqz a3, .Ltry_update_is_executing
/* We may have a new heir */
/* Read the executing and heir */
LREG a4, PER_CPU_OFFSET_EXECUTING(a2)
LREG a5, PER_CPU_OFFSET_HEIR(a2)
/*
* Update the executing only if necessary to avoid cache line
* monopolization.
*/
beq a4, a5, .Ltry_update_is_executing
/* Calculate the heir context pointer */
sub a4, a1, a4
add a1, a5, a4
/* Update the executing */
sw a5, PER_CPU_OFFSET_EXECUTING(a2)
j .Ltry_update_is_executing
#endif
