ofw_subr.S revision 1.8.36.1
1 /* $NetBSD: ofw_subr.S,v 1.8.36.1 2011/06/23 14:19:32 cherry Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996 Wolfgang Solfrank. 5 * Copyright (C) 1995, 1996 TooLs GmbH. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by TooLs GmbH. 19 * 4. The name of TooLs GmbH may not be used to endorse or promote products 20 * derived from this software without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 25 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 26 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 27 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 28 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 30 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 31 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 35 .local firmstk 36 .globl openfirmware_entry 37 .local ofwsrsave 38 .local OF_buffer 39 40 .lcomm firmstk,NBPG,16 41 .lcomm OF_buffer,NBPG,4 42 .comm openfirmware_entry,4,4 /* openfirmware entry point */ 43 .lcomm ofwsrsave,64,4 /* openfirmware SR savearea */ 44 .lcomm ofwmsr,20,4 /* msr & sprg[0-3] used in OF */ 45 .comm ofwreal_incharge,4,4 46 47 /* 48 * Called by start to save the initial OFW state so we can restore it 49 * when call back to OFW. 50 */ 51 ENTRY_NOPROFILE(ofwinit) 52 #ifdef FIRMWORKSBUGS 53 mfmsr %r0 54 andi. %r0,%r0,PSL_IR|PSL_DR 55 beq 1f 56 57 li %r8,1 58 lis %r9,ofwreal_incharge@ha 59 stw %r8,ofwreal_incharge@l(%r9) 60 61 mflr %r30 62 bl _C_LABEL(ofwr_init) 63 mtlr %r30 64 1: 65 #endif 66 lis %r8,openfirmware_entry@ha 67 stw %r5,openfirmware_entry@l(%r8) /* save client interface handler*/ 68 69 mfmsr %r0 70 li %r8,PSL_IP 71 andc %r0,%r0,%r8 /* make sure PSL_IP is off */ 72 lis %r9,ofwmsr@ha 73 stwu %r0,ofwmsr@l(%r9) /* save initial MSR value */ 74 75 mfsprg0 %r0 /* save SPRGs */ 76 stw %r0,4(%r9) 77 mfsprg1 %r0 78 stw %r0,8(%r9) 79 mfsprg2 %r0 80 stw %r0,12(%r9) 81 mfsprg3 %r0 82 stw %r0,16(%r9) 83 84 lis %r8,OF_buffer@ha 85 addi %r8,%r8,OF_buffer@l 86 lis %r9,_C_LABEL(OF_buf)@ha 87 stw %r8,_C_LABEL(OF_buf)@l(%r9) 88 89 blr 90 91 /* 92 * OpenFirmware entry point 93 */ 94 .text 95 ENTRY(openfirmware) 96 mflr %r0 /* save return address */ 97 stw %r0,4(%r1) 98 stwu %r1,-32(%r1) /* setup stack frame */ 99 100 lis %r4,openfirmware_entry@ha /* get firmware entry point */ 101 lwz %r4,openfirmware_entry@l(%r4) 102 mtlr %r4 103 104 mfsprg0 %r5 /* save current sprg0 (curcpu) */ 105 stw %r5,16(%r1) 106 mfsprg1 %r5 /* save current sprg1 */ 107 stw %r5,20(%r1) 108 mfsprg2 %r5 /* save current sprg1 */ 109 stw %r5,24(%r1) 110 mfsprg3 %r5 /* save current sprg3 */ 111 stw %r5,28(%r1) 112 113 #ifdef FIRMWORKSBUGS 114 lis %r4,ofwreal_incharge@ha 115 lwz %r4,ofwreal_incharge@l(%r4) 116 cmpwi %r4,1 117 bne 1f 118 blrl 119 b 4f 120 1: 121 #endif 122 mfmsr %r4 /* save msr */ 123 stw %r4,8(%r1) 124 125 li %r0,0 /* clear battable translations */ 126 mtmsr %r0 127 #if defined (PPC_OEA) || defined (PPC_OEA64_BRIDGE) 128 mtdbatu 2,%r0 129 mtdbatu 3,%r0 130 mtibatu 2,%r0 131 mtibatu 3,%r0 132 #endif /* PPC_OEA */ 133 134 lis %r4,ofwsrsave@ha /* save current SRs */ 135 addi %r4,%r4,ofwsrsave@l 136 li %r5,0 137 1: mfsrin %r0,%r5 138 stw %r0,0(%r4) 139 addi %r4,%r4,4 140 addis %r5,%r5,0x10000000@h 141 cmpwi %r5,0 142 bne 1b 143 144 lis %r4,_C_LABEL(ofw_pmap)@ha /* load OFW SR */ 145 addi %r4,%r4,_C_LABEL(ofw_pmap)@l 146 lwz %r0,PM_KERNELSR(%r4) 147 cmpwi %r0,0 /* pm_sr[KERNEL_SR] == 0? */ 148 beq 2f /* then skip (not initialized yet) */ 149 li %r5,0 150 1: lwz %r0,0(%r4) 151 mtsrin %r0,%r5 152 addi %r4,%r4,4 153 addis %r5,%r5,0x10000000@h 154 cmpwi %r5,0 155 bne 1b 156 2: 157 lis %r4,ofwmsr+16@ha /* Open Firmware msr + sprg[0-3] */ 158 lwzu %r5,ofwmsr+16@l(%r4) 159 mtsprg3 %r5 160 lwz %r5,-4(%r4) 161 mtsprg2 %r5 162 lwz %r5,-8(%r4) 163 mtsprg1 %r5 164 lwz %r5,-12(%r4) 165 mtsprg0 %r5 166 lwz %r5,-16(%r4) 167 mtmsr %r5 168 isync 169 170 blrl /* call Open Firmware */ 171 172 lis %r4,ofwsrsave@ha /* restore saved SRs */ 173 addi %r4,%r4,ofwsrsave@l 174 li %r5,0 175 1: lwz %r0,0(%r4) 176 mtsrin %r0,%r5 177 addi %r4,%r4,4 178 addis %r5,%r5,0x10000000@h 179 cmpwi %r5,0 180 bne 1b 181 182 lwz %r4,8(%r1) /* restore msr */ 183 mtmsr %r4 184 isync 185 4: 186 lwz %r5,16(%r1) /* restore saved sprgs (curcpu) */ 187 mtsprg0 %r5 188 lwz %r5,20(%r1) 189 mtsprg1 %r5 190 lwz %r5,24(%r1) 191 mtsprg2 %r5 192 lwz %r5,28(%r1) 193 mtsprg3 %r5 194 195 lwz %r1,0(%r1) /* and return */ 196 lwz %r0,4(%r1) 197 mtlr %r0 198 blr 199 200 /* 201 * Switch to/from OpenFirmware real mode stack 202 * 203 * Note: has to be called as the very first thing in OpenFirmware interface 204 * routines. 205 * E.g.: 206 * int 207 * OF_xxx(arg1, arg2) 208 * type arg1, arg2; 209 * { 210 * static struct { 211 * char *name; 212 * int nargs; 213 * int nreturns; 214 * char *method; 215 * int arg1; 216 * int arg2; 217 * int ret; 218 * } args = { 219 * "xxx", 220 * 2, 221 * 1, 222 * }; 223 * 224 * ofw_stack(); 225 * args.arg1 = arg1; 226 * args.arg2 = arg2; 227 * if (openfirmware(&args) < 0) 228 * return -1; 229 * return args.ret; 230 * } 231 */ 232 233 ENTRY(ofw_stack) 234 mfmsr %r8 /* turn off interrupts */ 235 andi. %r0,%r8,~(PSL_EE|PSL_RI)@l 236 mtmsr %r0 237 stw %r8,4(%r1) /* abuse return address slot */ 238 239 lwz %r5,0(%r1) /* get length of stack frame */ 240 subf %r5,%r1,%r5 241 242 lis %r7,firmstk+NBPG-8@ha 243 addi %r7,%r7,firmstk+NBPG-8@l 244 lis %r6,ofw_back@ha 245 addi %r6,%r6,ofw_back@l 246 subf %r4,%r5,%r7 /* make room for stack frame on 247 new stack */ 248 stw %r6,-4(%r7) /* setup return pointer */ 249 stwu %r1,-8(%r7) 250 251 stw %r7,-8(%r4) 252 253 addi %r3,%r1,8 254 addi %r1,%r4,-8 255 subi %r5,%r5,8 256 257 b _C_LABEL(ofbcopy) /* and copy it */ 258 259 ofw_back: 260 lwz %r1,0(%r1) /* get callers original stack pointer */ 261 262 lwz %r0,4(%r1) /* get saved msr from abused slot */ 263 mtmsr %r0 264 265 lwz %r1,0(%r1) /* return */ 266 lwz %r0,4(%r1) 267 mtlr %r0 268 blr 269
Indexes created Sun Oct 19 02:09:48 GMT 2025