ofw_subr.S revision 1.6
1 /* $NetBSD: ofw_subr.S,v 1.6 2008/01/28 21:06:29 garbled 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 .data 41 GLOBAL(ofmsr) 42 .long 0,0,0,0,0 /* msr & sprg[0-3] used in OF */ 43 44 GLOBAL(ofwsprg0save) 45 .long 0 46 47 GLOBAL(ofwreal_incharge) 48 .long 0 49 50 .comm firmstk,NBPG,8 51 .comm OF_buffer,NBPG,4 52 .comm openfirmware_entry,4,4 /* openfirmware entry point */ 53 .comm ofwsrsave,64,4 /* openfirmware SR savearea */ 54 55 /* 56 * Called by start to save the initial OFW state so we can restore it 57 * when call back to OFW. 58 */ 59 ENTRY_NOPROFILE(ofwinit) 60 #ifdef FIRMWORKSBUGS 61 mfmsr 0 62 andi. 0,0,PSL_IR|PSL_DR 63 beq 1f 64 65 li 8,1 66 lis 9,ofwreal_incharge@ha 67 stw 8,ofwreal_incharge@l(9) 68 69 mflr 30 70 bl _C_LABEL(ofwr_init) 71 mtlr 30 72 1: 73 #endif 74 lis 8,openfirmware_entry@ha 75 stw 5,openfirmware_entry@l(8) /* save client interface handler*/ 76 77 mfmsr 0 78 lis 9,ofmsr@ha 79 stwu 0,ofmsr@l(9) /* save initial MSR value */ 80 81 mfsprg 0,0 /* save SPRGs */ 82 stwu 0,4(9) 83 mfsprg 0,1 84 stwu 0,4(9) 85 mfsprg 0,2 86 stwu 0,4(9) 87 mfsprg 0,3 88 stw 0,4(9) 89 90 lis 8,OF_buffer@ha 91 addi 8,8,OF_buffer@l 92 lis 9,_C_LABEL(OF_buf)@ha 93 stw 8,_C_LABEL(OF_buf)@l(9) 94 95 blr 96 97 /* 98 * OpenFirmware entry point 99 */ 100 .text 101 ENTRY(openfirmware) 102 mflr 0 /* save return address */ 103 stw 0,4(1) 104 stwu 1,-16(1) /* setup stack frame */ 105 106 lis 4,openfirmware_entry@ha /* get firmware entry point */ 107 lwz 4,openfirmware_entry@l(4) 108 mtlr 4 109 110 mfsprg 5,0 /* save current sprg0 (curcpu) */ 111 lis 4,ofwsprg0save@ha 112 addi 4,4,ofwsprg0save@l 113 stw 5,0(4) 114 115 #ifdef FIRMWORKSBUGS 116 lis 4,ofwreal_incharge@ha 117 lwz 4,ofwreal_incharge@l(4) 118 cmpwi 4,1 119 bne 1f 120 blrl 121 b 4f 122 1: 123 #endif 124 mfmsr 4 /* save msr */ 125 stw 4,8(1) 126 127 li 0,0 /* clear battable translations */ 128 #if defined (PPC_OEA) || defined (PPC_OEA64_BRIDGE) 129 mtdbatu 2,0 130 mtdbatu 3,0 131 mtibatu 2,0 132 mtibatu 3,0 133 #endif /* PPC_OEA */ 134 135 lis 4,ofwsrsave@ha /* save current SRs */ 136 addi 4,4,ofwsrsave@l 137 li 5,0 138 1: mfsrin 0,5 139 stw 0,0(4) 140 addi 4,4,4 141 addis 5,5,0x10000000@h 142 cmpwi 5,0 143 bne 1b 144 145 lis 4,_C_LABEL(ofw_pmap)@ha /* load OFW SR */ 146 addi 4,4,_C_LABEL(ofw_pmap)@l 147 lwz 0,PM_KERNELSR(4) 148 cmpwi 0,0 /* pm_sr[KERNEL_SR] == 0? */ 149 beq 2f /* then skip (not initialized yet) */ 150 li 5,0 151 1: lwz 0,0(4) 152 mtsrin 0,5 153 addi 4,4,4 154 addis 5,5,0x10000000@h 155 cmpwi 5,0 156 bne 1b 157 2: 158 lis 4,ofmsr@ha /* Open Firmware msr + sprg[0-3] */ 159 lwzu 5,ofmsr+16@l(4) 160 mtsprg 3,5 161 lwzu 5,-4(4) 162 mtsprg 2,5 163 lwzu 5,-4(4) 164 mtsprg 1,5 165 lwzu 5,-4(4) 166 mtsprg 0,5 167 lwz 5,-4(4) 168 mtmsr 5 169 isync 170 171 blrl /* call Open Firmware */ 172 173 lis 4,ofwsrsave@ha /* restore saved SRs */ 174 addi 4,4,ofwsrsave@l 175 li 5,0 176 1: lwz 0,0(4) 177 mtsrin 0,5 178 addi 4,4,4 179 addis 5,5,0x10000000@h 180 cmpwi 5,0 181 bne 1b 182 183 lwz 4,8(1) /* restore msr */ 184 mtmsr 4 185 isync 186 4: 187 lis 4,ofwsprg0save@ha /* restore saved sprg0 (curcpu) */ 188 addi 4,4,ofwsprg0save@l 189 lwz 5,0(4) 190 mtsprg 0,5 191 192 lwz 1,0(1) /* and return */ 193 lwz 0,4(1) 194 mtlr 0 195 blr 196 197 /* 198 * Switch to/from OpenFirmware real mode stack 199 * 200 * Note: has to be called as the very first thing in OpenFirmware interface 201 * routines. 202 * E.g.: 203 * int 204 * OF_xxx(arg1, arg2) 205 * type arg1, arg2; 206 * { 207 * static struct { 208 * char *name; 209 * int nargs; 210 * int nreturns; 211 * char *method; 212 * int arg1; 213 * int arg2; 214 * int ret; 215 * } args = { 216 * "xxx", 217 * 2, 218 * 1, 219 * }; 220 * 221 * ofw_stack(); 222 * args.arg1 = arg1; 223 * args.arg2 = arg2; 224 * if (openfirmware(&args) < 0) 225 * return -1; 226 * return args.ret; 227 * } 228 */ 229 230 ENTRY(ofw_stack) 231 mfmsr 8 /* turn off interrupts */ 232 andi. 0,8,~(PSL_EE|PSL_RI)@l 233 mtmsr 0 234 stw 8,4(1) /* abuse return address slot */ 235 236 lwz 5,0(1) /* get length of stack frame */ 237 subf 5,1,5 238 239 lis 7,firmstk+NBPG-8@ha 240 addi 7,7,firmstk+NBPG-8@l 241 lis 6,ofw_back@ha 242 addi 6,6,ofw_back@l 243 subf 4,5,7 /* make room for stack frame on 244 new stack */ 245 stw 6,-4(7) /* setup return pointer */ 246 stwu 1,-8(7) 247 248 stw 7,-8(4) 249 250 addi 3,1,8 251 addi 1,4,-8 252 subi 5,5,8 253 254 b _C_LABEL(ofbcopy) /* and copy it */ 255 256 ofw_back: 257 lwz 1,0(1) /* get callers original stack pointer */ 258 259 lwz 0,4(1) /* get saved msr from abused slot */ 260 mtmsr 0 261 262 lwz 1,0(1) /* return */ 263 lwz 0,4(1) 264 mtlr 0 265 blr 266
Indexes created Sun Oct 19 02:09:48 GMT 2025