1/* 2 * Copyright (c) 2011 Aeroflex Gaisler 3 * 4 * BSD license: 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a copy 7 * of this software and associated documentation files (the "Software"), to deal 8 * in the Software without restriction, including without limitation the rights 9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 10 * copies of the Software, and to permit persons to whom the Software is 11 * furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 22 * THE SOFTWARE. 23 */ 24 25 26#include <asm-leon/leonstack.h> 27#include <asm-leon/winmacros.h> 28 29/* Registers to not touch at all. */ 30#define t_psr l0 /* Set by caller */ 31#define t_pc l1 /* Set by caller */ 32#define t_npc l2 /* Set by caller */ 33#define t_wim l3 /* Set by caller */ 34#define t_twinmask l4 /* Set at beginning of this entry routine. */ 35#define t_kstack l5 /* Set right before pt_regs frame is built */ 36#define t_retpc l6 /* If you change this, change winmacro.h header file */ 37#define t_systable l7 /* Never touch this, could be the syscall table ptr. */ 38#define curptr g6 /* Set after pt_regs frame is built */ 39 40 /* Number of register windows */ 41 .global _nwindows_min1, _nwindows 42 43 .text 44 .align 4 45 .globl leonbare_trapsetup 46 47leonbare_trapsetup: 48 49#ifdef _FLAT 50 restore 51 RW_STORE(sp) 52 save 53#endif 54 55#ifndef _SOFT_FLOAT 56 /* build a pt_regs trap frame. */ 57 sub %fp, (SF_REGS_SZ + PT_REGS_SZ + FW_REGS_SZ), %t_kstack 58 PT_STORE_ALL(t_kstack, t_psr, t_pc, t_npc, g2) 59 60 /* build a fp_regs trap frame. */ 61 sethi %hi(fpustate_current), %g2 62 ld [%g2+%lo(fpustate_current)], %g3 63 st %g3,[%t_kstack + (SF_REGS_SZ + PT_REGS_SZ + FW_REGS_SZ - 4)] 64 add %t_kstack,SF_REGS_SZ + PT_REGS_SZ,%g3 65 st %g3, [%g2+%lo(fpustate_current)] 66 67#else 68 /* build a pt_regs trap frame. 69 */ 70 sub %fp, (SF_REGS_SZ + PT_REGS_SZ), %t_kstack 71 PT_STORE_ALL(t_kstack, t_psr, t_pc, t_npc, g2) 72#endif 73 74 75#ifndef _FLAT 76 /* See if we are in the trap window. */ 77 mov 1, %t_twinmask 78 sll %t_twinmask, %t_psr, %t_twinmask ! t_twinmask = (1 << psr) 79 andcc %t_twinmask, %t_wim, %g0 80 beq 1f ! in trap window, clean up 81 nop 82 83 /*-------------------------------------------------*/ 84 /* Spill , adjust %wim and go. */ 85 srl %t_wim, 0x1, %g2 ! begin computation of new %wim 86 87 sethi %hi(_nwindows_min1), %g3 88 ld [%g3+%lo(_nwindows_min1)], %g3 89 90 sll %t_wim, %g3, %t_wim ! NWINDOWS-1 91 or %t_wim, %g2, %g2 92 and %g2, 0xff, %g2 93 94 save %g0, %g0, %g0 ! get in window to be saved 95 96 /* Set new %wim value */ 97 wr %g2, 0x0, %wim 98 99 /* Save the kernel window onto the corresponding stack. */ 100 RW_STORE(sp) 101 102 restore %g0, %g0, %g0 103 /*-------------------------------------------------*/ 104 1051: 106#endif 107 /* Trap from kernel with a window available. 108 * Just do it... 109 */ 110 jmpl %t_retpc + 0x8, %g0 ! return to caller 111 mov %t_kstack, %sp ! jump onto new stack 112 113 114