setstack.S revision 1.1.2.2
1 1.1.2.2 lukem /* $NetBSD: setstack.S,v 1.1.2.2 2001/08/03 04:10:59 lukem Exp $ */ 2 1.1.2.2 lukem 3 1.1.2.2 lukem /* 4 1.1.2.2 lukem * Copyright (c) 1994 Mark Brinicombe. 5 1.1.2.2 lukem * Copyright (c) 1994 Brini. 6 1.1.2.2 lukem * All rights reserved. 7 1.1.2.2 lukem * 8 1.1.2.2 lukem * This code is derived from software written for Brini by Mark Brinicombe 9 1.1.2.2 lukem * 10 1.1.2.2 lukem * Redistribution and use in source and binary forms, with or without 11 1.1.2.2 lukem * modification, are permitted provided that the following conditions 12 1.1.2.2 lukem * are met: 13 1.1.2.2 lukem * 1. Redistributions of source code must retain the above copyright 14 1.1.2.2 lukem * notice, this list of conditions and the following disclaimer. 15 1.1.2.2 lukem * 2. Redistributions in binary form must reproduce the above copyright 16 1.1.2.2 lukem * notice, this list of conditions and the following disclaimer in the 17 1.1.2.2 lukem * documentation and/or other materials provided with the distribution. 18 1.1.2.2 lukem * 3. All advertising materials mentioning features or use of this software 19 1.1.2.2 lukem * must display the following acknowledgement: 20 1.1.2.2 lukem * This product includes software developed by Brini. 21 1.1.2.2 lukem * 4. The name of the company nor the name of the author may be used to 22 1.1.2.2 lukem * endorse or promote products derived from this software without specific 23 1.1.2.2 lukem * prior written permission. 24 1.1.2.2 lukem * 25 1.1.2.2 lukem * THIS SOFTWARE IS PROVIDED BY BRINI ``AS IS'' AND ANY EXPRESS OR IMPLIED 26 1.1.2.2 lukem * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 27 1.1.2.2 lukem * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 28 1.1.2.2 lukem * IN NO EVENT SHALL BRINI OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 29 1.1.2.2 lukem * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 30 1.1.2.2 lukem * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 31 1.1.2.2 lukem * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 1.1.2.2 lukem * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 1.1.2.2 lukem * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 1.1.2.2 lukem * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 1.1.2.2 lukem * SUCH DAMAGE. 36 1.1.2.2 lukem * 37 1.1.2.2 lukem * RiscBSD kernel project 38 1.1.2.2 lukem * 39 1.1.2.2 lukem * setstack.S 40 1.1.2.2 lukem * 41 1.1.2.2 lukem * Miscellaneous routine to play with the stack pointer in different CPU modes 42 1.1.2.2 lukem * 43 1.1.2.2 lukem * Eventually this routine can be inline assembly. 44 1.1.2.2 lukem * 45 1.1.2.2 lukem * Created : 17/09/94 46 1.1.2.2 lukem * 47 1.1.2.2 lukem * Based of kate/display/setstack.s 48 1.1.2.2 lukem */ 49 1.1.2.2 lukem 50 1.1.2.2 lukem #include <machine/cpu.h> 51 1.1.2.2 lukem #include <machine/asm.h> 52 1.1.2.2 lukem 53 1.1.2.2 lukem /* To set the stack pointer for a particular mode we must switch 54 1.1.2.2 lukem * to that mode update the banked r13 and then switch back. 55 1.1.2.2 lukem * This routine provides an easy way of doing this for any mode 56 1.1.2.2 lukem * 57 1.1.2.2 lukem * r0 = CPU mode 58 1.1.2.2 lukem * r1 = stackptr 59 1.1.2.2 lukem */ 60 1.1.2.2 lukem 61 1.1.2.2 lukem ENTRY(set_stackptr) 62 1.1.2.2 lukem mrs r3, cpsr_all /* Switch to the appropriate mode */ 63 1.1.2.2 lukem bic r2, r3, #(PSR_MODE) 64 1.1.2.2 lukem orr r2, r2, r0 65 1.1.2.2 lukem msr cpsr_all, r2 66 1.1.2.2 lukem 67 1.1.2.2 lukem mov sp, r1 /* Set the stack pointer */ 68 1.1.2.2 lukem 69 1.1.2.2 lukem msr cpsr_all, r3 /* Restore the old mode */ 70 1.1.2.2 lukem 71 1.1.2.2 lukem mov pc, lr /* Exit */ 72 1.1.2.2 lukem 73 1.1.2.2 lukem /* To get the stack pointer for a particular mode we must switch 74 1.1.2.2 lukem * to that mode copy the banked r13 and then switch back. 75 1.1.2.2 lukem * This routine provides an easy way of doing this for any mode 76 1.1.2.2 lukem * 77 1.1.2.2 lukem * r0 = CPU mode 78 1.1.2.2 lukem */ 79 1.1.2.2 lukem 80 1.1.2.2 lukem ENTRY(get_stackptr) 81 1.1.2.2 lukem mrs r3, cpsr_all /* Switch to the appropriate mode */ 82 1.1.2.2 lukem bic r2, r3, #(PSR_MODE) 83 1.1.2.2 lukem orr r2, r2, r0 84 1.1.2.2 lukem msr cpsr_all, r2 85 1.1.2.2 lukem 86 1.1.2.2 lukem mov r0, sp /* Set the stack pointer */ 87 1.1.2.2 lukem 88 1.1.2.2 lukem msr cpsr_all, r3 /* Restore the old mode */ 89 1.1.2.2 lukem 90 1.1.2.2 lukem mov pc, lr /* Exit */ 91 1.1.2.2 lukem 92 1.1.2.2 lukem /* End of setstack.S */ 93
Indexes created Thu Oct 02 07:10:07 GMT 2025