/*
* Copyright (c) 2005 Jakub Jermar
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - 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.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
*/
#include <abi/asmtool.h>
#include <arch/register.h>
.text
/** Copy memory from/to userspace.
*
* This memcpy() has been taken from the assembler output of
* a plain C implementation of memcpy() modified to have the
* failover part.
*
* @param in0 Destination address.
* @param in1 Source address.
* @param in2 Number of byte to copy.
*
*/
FUNCTION_BEGIN(memcpy_from_uspace)
FUNCTION_BEGIN(memcpy_to_uspace)
alloc loc0 = ar.pfs, 3, 1, 0, 0
adds r14 = 7, in1
mov r2 = ar.lc
mov r8 = in0 ;;
and r14 = -8, r14 ;;
cmp.ne p6, p7 = r14, in1
(p7) br.cond.dpnt 3f ;;
0:
cmp.ne p6, p7 = 0, in2
(p7) br.cond.dpnt 2f ;;
(p6) adds r14 = -1, in2
(p6) mov r16 = r0
(p6) mov r17 = r0 ;;
(p6) mov ar.lc = r14
1:
add r14 = r16, in1
add r15 = r16, in0
adds r17 = 1, r17 ;;
ld1 r14 = [r14]
mov r16 = r17 ;;
st1 [r15] = r14
br.cloop.sptk.few 1b ;;
2:
mov ar.lc = r2
mov ar.pfs = loc0
br.ret.sptk.many rp
3:
adds r14 = 7, in0 ;;
and r14 = -8, r14 ;;
cmp.eq p6, p7 = r14, in0
(p7) br.cond.dptk 0b
shr.u r18 = in2, 3 ;;
cmp.ne p6, p7 = 0, r18
(p7) br.cond.dpnt 5f ;;
(p6) adds r14 = -1, r18
(p6) mov r16 = r0
(p6) mov r17 = r0 ;;
(p6) mov ar.lc = r14
4:
shladd r14 = r16, 3, r0
adds r16 = 1, r17 ;;
add r15 = in1, r14
add r14 = in0, r14
mov r17 = r16 ;;
ld8 r15 = [r15] ;;
st8 [r14] = r15
br.cloop.sptk.few 4b
5:
and r15 = 7, in2
shladd r14 = r18, 3, r0
mov r16 = r0
mov r18 = r0 ;;
cmp.eq p6, p7 = 0, r15
add in0 = r14, in0
adds r15 = -1, r15
add r17 = r14, in1
(p6) br.cond.dpnt 2b ;;
mov ar.lc = r15
6:
add r14 = r16, r17
add r15 = r16, in0
adds r16 = 1, r18 ;;
ld1 r14 = [r14]
mov r18 = r16 ;;
st1 [r15] = r14
br.cloop.sptk.few 6b ;;
mov ar.lc = r2
mov ar.pfs = loc0
br.ret.sptk.many rp
FUNCTION_END(memcpy_from_uspace)
FUNCTION_END(memcpy_to_uspace)
SYMBOL(memcpy_from_uspace_failover_address)
SYMBOL(memcpy_to_uspace_failover_address)
/* Return 0 on failure */
mov r8 = r0
mov ar.pfs = loc0
br.ret.sptk.many rp
FUNCTION_BEGIN(cpu_halt)
br cpu_halt
FUNCTION_END(cpu_halt)
/** Switch to userspace - low level code.
*
* @param in0 Userspace entry point address.
* @param in1 Userspace stack pointer address.
* @param in2 Userspace register stack pointer address.
* @param in3 Userspace address of thread uspace_arg_t structure.
* @param in4 Value to be stored in IPSR.
* @param in5 Value to be stored in RSC.
*
*/
FUNCTION_BEGIN(switch_to_userspace)
alloc loc0 = ar.pfs, 6, 3, 0, 0
/* Disable interruption collection and interrupts */
rsm (PSR_IC_MASK | PSR_I_MASK)
srlz.d ;;
srlz.i ;;
mov cr.ipsr = in4
mov cr.iip = in0
mov r12 = in1
xor r1 = r1, r1
/* r2 is defined to hold pcb_ptr - set it to 0 */
xor r2 = r2, r2
mov loc1 = cr.ifs
movl loc2 = PFM_MASK ;;
and loc1 = loc2, loc1 ;;
mov cr.ifs = loc1 ;; /* prevent decrementing BSP by rfi */
invala
mov loc1 = ar.rsc ;;
and loc1 = ~3, loc1 ;;
mov ar.rsc = loc1 ;; /* put RSE into enforced lazy mode */
flushrs ;;
mov ar.bspstore = in2 ;;
mov ar.rsc = in5 ;;
mov r8 = in3
rfi ;;
FUNCTION_END(switch_to_userspace)
FUNCTION_BEGIN(early_putuchar)
br.ret.sptk.many b0
FUNCTION_END(early_putuchar)