srt0.S revision 1.7
1 /* $NetBSD: srt0.S,v 1.7 2001/11/21 21:38:00 uwe Exp $ */ 2 3 /*- 4 * Copyright (c) 1999 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Paul Kranenburg. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #define _LOCORE /* XXX - fix Makefile */ 40 41 #include <machine/param.h> 42 #include <machine/asm.h> 43 #include <machine/psl.h> 44 45 #define CCFSZ 96 46 47 .file "str0.s" 48 49 .comm _C_LABEL(romp), 4 50 .comm _C_LABEL(cputyp), 4 51 .comm _C_LABEL(nbpg), 4 52 .comm _C_LABEL(pgofset), 4 53 .comm _C_LABEL(pgshift), 4 54 55 .text 56 .globl start 57 58 start: 59 /* 60 * Set up a stack. 61 */ 62 set start, %o1 63 save %o1, -CCFSZ, %sp 64 65 /* 66 * Find which address we are at. 67 */ 68 1: call 2f 69 sethi %hi(1b), %l0 70 2: or %l0, %lo(1b), %l0 71 cmp %l0, %o7 ! %o7 contains actual address of 1b 72 beq 4f ! already there, no need to relocate 73 nop 74 75 /* 76 * Relocate. 77 */ 78 add %o7, (start-1b), %l0 79 set start, %l1 80 set _edata, %o0 81 sub %o0, %l1, %l2 ! length 82 3: ld [%l0], %o0 83 add %l0, 4, %l0 84 st %o0, [%l1] 85 subcc %l2, 4, %l2 86 bg 3b 87 add %l1, 4, %l1 88 89 /* 90 * Jump to our relocated self. 91 */ 92 set 4f, %g1 93 jmp %g1 94 nop 95 96 4: 97 #ifdef notyet 98 /* 99 * Enable traps 100 */ 101 wr %g0, 0, %wim ! make sure we can set psr 102 nop; nop; nop 103 wr %g0, PSR_S|PSR_PS|PSR_PIL, %psr ! set initial psr 104 nop; nop; nop 105 wr %g0, 2, %wim ! set initial %wim (w1 invalid) 106 107 rd %psr, %l0 108 wr %l0, PSR_ET, %psr 109 nop; nop; nop 110 #endif 111 112 /* 113 * Clear BSS 114 */ 115 set _edata, %o0 ! bzero(edata, end - edata) 116 set _end, %o1 117 /* note: bzero() expanded inline for compactness */ 118 subcc %o1, %o0, %o1 119 bz 2f ! in case there is no BSS 120 121 srl %o1, 2, %o1 ! assume _edata & _end are aligned 122 1: 123 st %g0, [%o0] ! while (n--) 124 subcc %o1, 1, %o1 ! *p = 0; etc.. 125 bnz 1b 126 add %o0, 4, %o0 127 2: 128 129 /* 130 * Enable interrupts, but only above level 11. This enables "L1-A", 131 * but avoids spurious interrupt bites from most other devices. 132 */ 133 rd %psr, %o0 134 andn %o0, PSR_PIL, %o0 135 wr %o0, 0xb00, %psr ! (11 << 8) 136 nop; nop; nop 137 138 /* 139 * Set CPU type that we are running on. 140 */ 141 sethi %hi(_C_LABEL(cputyp)), %o0 142 set 0x4000, %g7 143 cmp %i0, %g7 144 beq is_sun4 145 nop 146 147 mov CPU_SUN4C, %g4 148 mov SUN4CM_PGSHIFT, %g5 149 150 /* 151 * OpenProm machines pass PROM vector in %o0 (%i0 after save) 152 * OpenFirm machines pass OF entry in %o3 (%i3 after save) 153 */ 154 cmp %i0, 0 155 be is_openfirm 156 nop 157 158 ! save address of PROM vector 159 sethi %hi(_C_LABEL(romp)), %o1 160 st %i0, [%o1 + %lo(_C_LABEL(romp))] 161 b,a is_sun4cm 162 163 is_openfirm: 164 ! save address of OpenFirmware client interface handler 165 sethi %hi(_C_LABEL(romp)), %o1 166 st %i3, [%o1 + %lo(_C_LABEL(romp))] 167 b,a is_sun4cm 168 169 is_sun4: 170 mov CPU_SUN4, %g4 171 mov SUN4_PGSHIFT, %g5 172 173 is_sun4cm: 174 st %g4, [%o0 + %lo(_C_LABEL(cputyp))] 175 sethi %hi(_C_LABEL(pgshift)), %o0 ! pgshift = log2(nbpg) 176 st %g5, [%o0 + %lo(_C_LABEL(pgshift))] 177 178 mov 1, %o0 ! nbpg = 1 << pgshift 179 sll %o0, %g5, %g5 180 sethi %hi(_C_LABEL(nbpg)), %o0 ! nbpg = bytes in a page 181 st %g5, [%o0 + %lo(_C_LABEL(nbpg))] 182 183 sub %g5, 1, %g5 184 sethi %hi(_C_LABEL(pgofset)), %o0 ! page offset = nbpg - 1 185 st %g5, [%o0 + %lo(_C_LABEL(pgofset))] 186 187 call _C_LABEL(main) 188 mov %i0, %o0 189 190 ret 191 restore 192 193 /* 194 * NO-OP place holder function. 195 */ 196 ENTRY(sparc_noop) 197 retl 198 nop 199 200 201 #ifdef TIGHT 202 203 /* 204 * XXX - Space saving .div & .rem routines (small & non-negative numbres only) 205 */ 206 .align 4 207 .global .div, .udiv 208 ! int n = 0; while (a >= b) { a -= b; n++; }; return n; 209 .div: 210 .udiv: 211 cmp %o0, %o1 212 bl 2f 213 mov 0, %o5 214 1: 215 sub %o0, %o1, %o0 216 cmp %o0, %o1 217 bge 1b 218 add %o5, 1, %o5 219 2: 220 retl 221 mov %o5, %o0 222 223 .align 4 224 .global .rem, .urem 225 ! while (a>=b) a -= b; return a; 226 .rem: 227 .urem: 228 cmp %o0, %o1 229 bl 2f 230 nop 231 sub %o0, %o1, %o0 232 1: 233 cmp %o0, %o1 234 bge,a 1b 235 sub %o0, %o1, %o0 236 2: 237 retl 238 nop 239 240 #endif /* TIGHT */ 241
Indexes created Fri Sep 26 20:09:58 GMT 2025