1/* $FreeBSD$ */ 2 3/*- 4 * Copyright (C) 2010-2016 Nathan Whitehorn 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 * 27 * $FreeBSD$ 28 */ 29 30#include "assym.inc" 31 32#include <sys/syscall.h> 33 34#include <machine/trap.h> 35#include <machine/param.h> 36#include <machine/spr.h> 37#include <machine/asm.h> 38#include <machine/vmparam.h> 39 40#ifdef _CALL_ELF 41.abiversion _CALL_ELF 42#endif 43 44/* Glue for linker script */ 45.globl kernbase 46.set kernbase, KERNBASE 47 48/* 49 * Globals 50 */ 51 .data 52 .align 3 53GLOBAL(__startkernel) 54 .llong begin 55GLOBAL(__endkernel) 56 .llong end 57GLOBAL(can_wakeup) 58 .llong 0x0 59 60 .align 4 61#define TMPSTKSZ 16384 /* 16K temporary stack */ 62GLOBAL(tmpstk) 63 .space TMPSTKSZ 64 65TOC_ENTRY(tmpstk) 66TOC_ENTRY(can_wakeup) 67 68#ifdef KDB 69#define TRAPSTKSZ 8192 /* 8k trap stack */ 70GLOBAL(trapstk) 71 .space TRAPSTKSZ 72TOC_ENTRY(trapstk) 73#endif 74 75 76/* 77 * Entry point for bootloaders that do not fully implement ELF and start 78 * at the beginning of the image (kexec, notably). In its own section so 79 * that it ends up before any linker-generated call stubs and actually at 80 * the beginning of the image. kexec on some systems also enters at 81 * (start of image) + 0x60, so put a spin loop there. 82 */ 83 .section ".text.kboot", "x", @progbits 84kbootentry: 85 b __start 86. = kbootentry + 0x40 /* Magic address used in platform layer */ 87 .global smp_spin_sem 88ap_kexec_spin_sem: 89 .long -1 90. = kbootentry + 0x60 /* Entry point for kexec APs */ 91ap_kexec_start: /* At 0x60 past start, copied to 0x60 by kexec */ 92 /* r3 set to CPU ID by kexec */ 93 94 /* Invalidate icache for low-memory copy and jump there */ 95 li %r0,0x80 96 dcbst 0,%r0 97 sync 98 icbi 0,%r0 99 isync 100 ba 0x80 /* Absolute branch to next inst */ 101 102. = kbootentry + 0x80 /* Aligned to cache line */ 1031: or 31,31,31 /* yield */ 104 sync 105 lwz %r1,0x40(0) /* Spin on ap_kexec_spin_sem */ 106 cmpw %r1,%r3 /* Until it equals our CPU ID */ 107 bne 1b 108 109 /* Released */ 110 or 2,2,2 /* unyield */ 111 112 /* Make sure that it will be software reset. Clear SRR1 */ 113 li %r1,0 114 mtsrr1 %r1 115 ba EXC_RST 116 117/* 118 * Now start the real text section 119 */ 120 121 .text 122 .globl btext 123btext: 124 125/* 126 * Main kernel entry point. 127 * 128 * Calling convention: 129 * r3: Flattened Device Tree pointer (or zero) 130 * r4: ignored 131 * r5: OF client interface pointer (or zero) 132 * r6: Loader metadata pointer (or zero) 133 * r7: Magic cookie (0xfb5d104d) to indicate that r6 has loader metadata 134 */ 135 .text 136ASENTRY_NOPROF(__start) 137 /* Set 64-bit mode if not yet set before branching to C */ 138 mfmsr %r20 139 li %r21,1 140 insrdi %r20,%r21,1,0 141 mtmsrd %r20 142 isync 143 nop /* Make this block a multiple of 8 bytes */ 144 145 /* Set up the TOC pointer */ 146 b 0f 147 .align 3 1480: nop 149 bl 1f 150 .llong __tocbase + 0x8000 - . 1511: mflr %r2 152 ld %r1,0(%r2) 153 add %r2,%r1,%r2 154 155 /* Get load offset */ 156 ld %r31,-0x8000(%r2) /* First TOC entry is TOC base */ 157 subf %r31,%r31,%r2 /* Subtract from real TOC base to get base */ 158 159 /* Set up the stack pointer */ 160 bl 1f 161 .llong tmpstk + TMPSTKSZ - 96 - . 1621: mflr %r30 163 ld %r1,0(%r30) 164 add %r1,%r1,%r30 165 nop 166 167 /* Relocate kernel */ 168 std %r3,48(%r1) 169 std %r4,56(%r1) 170 std %r5,64(%r1) 171 std %r6,72(%r1) 172 std %r7,80(%r1) 173 174 bl 1f 175 .llong _DYNAMIC-. 1761: mflr %r3 177 ld %r4,0(%r3) 178 add %r3,%r4,%r3 179 mr %r4,%r31 180 bl elf_reloc_self 181 nop 182 ld %r3,48(%r1) 183 ld %r4,56(%r1) 184 ld %r5,64(%r1) 185 ld %r6,72(%r1) 186 ld %r7,80(%r1) 187 188 /* Begin CPU init */ 189 mr %r4,%r2 /* Replace ignored r4 with tocbase for trap handlers */ 190 bl powerpc_init 191 nop 192 193 /* Set stack pointer to new value and branch to mi_startup */ 194 mr %r1, %r3 195 li %r3, 0 196 std %r3, 0(%r1) 197 bl mi_startup 198 nop 199 200 /* Unreachable */ 201 b . 202 203ASENTRY_NOPROF(__restartkernel_virtual) 204 /* 205 * When coming in via this entry point, we need to alter the SLB to 206 * shadow the segment register emulation entries in DMAP space. 207 * We need to do this dance because we are running with virtual-mode 208 * OpenFirmware and have not yet taken over the MMU. 209 * 210 * Assumptions: 211 * 1) The kernel is currently identity-mapped. 212 * 2) We are currently executing at an address compatible with 213 * real mode. 214 * 3) The first 16 SLB entries are emulating SRs. 215 * 4) The rest of the SLB is not in use. 216 * 5) OpenFirmware is not manipulating the SLB at runtime. 217 * 6) We are running on 64-bit AIM. 218 * 219 * Tested on a G5. 220 */ 221 mfmsr %r14 222 /* Switch to real mode because we are about to mess with the SLB. */ 223 andi. %r14, %r14, ~(PSL_DR|PSL_IR|PSL_ME|PSL_RI)@l 224 mtmsr %r14 225 isync 226 /* Prepare variables for later use. */ 227 li %r14, 0 228 li %r18, 0 229 oris %r18, %r18, 0xc000 230 sldi %r18, %r18, 32 /* r18: 0xc000000000000000 */ 2311: 232 /* 233 * Loop over the first 16 SLB entries. 234 * Offset the SLBE into the DMAP, add 16 to the index, and write 235 * it back to the SLB. 236 */ 237 /* XXX add more safety checks */ 238 slbmfev %r15, %r14 239 slbmfee %r16, %r14 240 or %r16, %r16, %r14 /* index is 0-15 */ 241 ori %r16, %r16, 0x10 /* add 16 to index. */ 242 or %r16, %r16, %r18 /* SLBE DMAP offset */ 243 rldicr %r17, %r16, 0, 37 /* Invalidation SLBE */ 244 245 isync 246 slbie %r17 247 /* isync */ 248 slbmte %r15, %r16 249 isync 250 addi %r14, %r14, 1 251 cmpdi %r14, 16 252 blt 1b 253 254ASENTRY_NOPROF(__restartkernel) 255 /* 256 * r3-r7: arguments to go to __start 257 * r8: offset from current kernel address to apply 258 * r9: MSR to set when (atomically) jumping to __start + r8 259 */ 260 mtsrr1 %r9 261 bl 1f 2621: mflr %r25 263 add %r25,%r8,%r25 264 addi %r25,%r25,2f-1b 265 mtsrr0 %r25 266 rfid 2672: bl __start 268 nop 269 270#include <powerpc/aim/trap_subr64.S> 271