newlib/libgloss/sparc_leon/rtrap_fast.S

159 lines
3.8 KiB
ArmAsm

/*
* Copyright (c) 2011 Aeroflex Gaisler
*
* BSD license:
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <asm-leon/leonstack.h>
#include <asm-leon/winmacros.h>
/* Registers to not touch at all. */
#define t_psr l0
#define t_pc l1
#define t_npc l2
#define t_wim l3
#define twin_tmp1 l4
#define glob_tmp g4
#define curptr g6
/* Number of register windows */
.global _nwindows_min1, _nwindows
.text
.align 4
.globl leonbare_trapreturn_fast, schedule_callback
/* rtap return special for irqtrap.S */
leonbare_trapreturn_fast:
/* a optional scheduler can be called here */
set schedule_callback, %g2
ld [%g2], %g2
cmp %g2,%g0
beq 3f
nop
jmpl %g2,%o7
#ifndef _SOFT_FLOAT
add %sp, FW_REGS_SZ + 8 + SF_REGS_SZ , %o1 ! pt_regs ptr
#else
add %sp, SF_REGS_SZ , %o1 ! pt_regs ptr
#endif
3:
#ifndef _SOFT_FLOAT
ld [%sp + (SF_REGS_SZ + PT_REGS_SZ + FW_REGS_SZ - 4)],%g2
sethi %hi(fpustate_current), %g3
st %g2, [%g3+%lo(fpustate_current)]
sethi %hi(fpustate_owner), %g3
ld [%g3+%lo(fpustate_owner)], %g3
cmp %g2, %g3
bne didusefpu
nop
/* avoid fpu exception */
ld [%sp + (SF_REGS_SZ + PT_REGS_SZ + FW_REGS_SZ - 8)], %g2
set SPARC_PSR_EF_MASK, %g3
and %g2, %g3, %g2
andn %t_psr, %g3, %t_psr
or %t_psr, %g2, %t_psr
ba,a 1f
didusefpu:
add %sp,SF_REGS_SZ + PT_REGS_SZ,%g2
cmp %g2, %g3
bne 1f
sethi %hi(fpustate_owner), %g3
st %g0, [%g3+%lo(fpustate_owner)]
1:
#endif
wr %t_psr, 0x0, %psr ! enable nesting again, clear ET
#ifndef _FLAT
/* Will the rett land us in the invalid window? */
mov 2, %g1
sll %g1, %t_psr, %g1
sethi %hi(_nwindows), %g2 !NWINDOWS
ld [%g2+%lo(_nwindows)], %g2
srl %g1, %g2, %g2
or %g1, %g2, %g1
rd %wim, %g2
andcc %g2, %g1, %g0
be 1f ! Nope, just return from the trap
sll %g2, 0x1, %g1
/* We have to grab a window before returning. */
sethi %hi(_nwindows_min1), %g3 !NWINDOWS-1
ld [%g3+%lo(_nwindows_min1)], %g3
srl %g2, %g3, %g2
or %g1, %g2, %g1
and %g1, 0xff, %g1
wr %g1, 0x0, %wim
/* Grrr, make sure we load from the right %sp... */
PT_LOAD_ALL_FAST(sp, t_psr, t_pc, t_npc, g1)
restore %g0, %g0, %g0
RW_LOAD(sp)
b 2f
save %g0, %g0, %g0
/* Reload the entire frame in case this is from a
* kernel system call or whatever...
*/
1:
#endif
PT_LOAD_ALL_FAST(sp, t_psr, t_pc, t_npc, g1)
2: /*PT_LOAD_GLOBALS(sp)*/
#ifdef _FLAT
restore
RW_LOAD(sp)
save
#endif
wr %t_psr, 0x0, %psr
nop; nop; nop
jmp %t_pc
rett %t_npc
#ifdef _FLAT
#warning _FLAT not implemented
#endif