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Diffstat (limited to 'libgloss/sparc_leon/etrap.S')
| -rw-r--r-- | libgloss/sparc_leon/etrap.S | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/libgloss/sparc_leon/etrap.S b/libgloss/sparc_leon/etrap.S new file mode 100644 index 000000000..7c4fe17d3 --- /dev/null +++ b/libgloss/sparc_leon/etrap.S @@ -0,0 +1,113 @@ +/* + * 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 /* Set by caller */ +#define t_pc l1 /* Set by caller */ +#define t_npc l2 /* Set by caller */ +#define t_wim l3 /* Set by caller */ +#define t_twinmask l4 /* Set at beginning of this entry routine. */ +#define t_kstack l5 /* Set right before pt_regs frame is built */ +#define t_retpc l6 /* If you change this, change winmacro.h header file */ +#define t_systable l7 /* Never touch this, could be the syscall table ptr. */ +#define curptr g6 /* Set after pt_regs frame is built */ + + /* Number of register windows */ + .global _nwindows_min1, _nwindows + + .text + .align 4 + .globl leonbare_trapsetup + +leonbare_trapsetup: + +#ifdef _FLAT + restore + RW_STORE(sp) + save +#endif + +#ifndef _SOFT_FLOAT + /* build a pt_regs trap frame. */ + sub %fp, (SF_REGS_SZ + PT_REGS_SZ + FW_REGS_SZ), %t_kstack + PT_STORE_ALL(t_kstack, t_psr, t_pc, t_npc, g2) + + /* build a fp_regs trap frame. */ + sethi %hi(fpustate_current), %g2 + ld [%g2+%lo(fpustate_current)], %g3 + st %g3,[%t_kstack + (SF_REGS_SZ + PT_REGS_SZ + FW_REGS_SZ - 4)] + add %t_kstack,SF_REGS_SZ + PT_REGS_SZ,%g3 + st %g3, [%g2+%lo(fpustate_current)] + +#else + /* build a pt_regs trap frame. + */ + sub %fp, (SF_REGS_SZ + PT_REGS_SZ), %t_kstack + PT_STORE_ALL(t_kstack, t_psr, t_pc, t_npc, g2) +#endif + + +#ifndef _FLAT + /* See if we are in the trap window. */ + mov 1, %t_twinmask + sll %t_twinmask, %t_psr, %t_twinmask ! t_twinmask = (1 << psr) + andcc %t_twinmask, %t_wim, %g0 + beq 1f ! in trap window, clean up + nop + + /*-------------------------------------------------*/ + /* Spill , adjust %wim and go. */ + srl %t_wim, 0x1, %g2 ! begin computation of new %wim + + sethi %hi(_nwindows_min1), %g3 + ld [%g3+%lo(_nwindows_min1)], %g3 + + sll %t_wim, %g3, %t_wim ! NWINDOWS-1 + or %t_wim, %g2, %g2 + and %g2, 0xff, %g2 + + save %g0, %g0, %g0 ! get in window to be saved + + /* Set new %wim value */ + wr %g2, 0x0, %wim + + /* Save the kernel window onto the corresponding stack. */ + RW_STORE(sp) + + restore %g0, %g0, %g0 + /*-------------------------------------------------*/ + +1: +#endif + /* Trap from kernel with a window available. + * Just do it... + */ + jmpl %t_retpc + 0x8, %g0 ! return to caller + mov %t_kstack, %sp ! jump onto new stack + + |