/*- * Copyright (C) 2010-2016 Nathan Whitehorn * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include "assym.inc" #include <sys/syscall.h> #include <machine/trap.h> #include <machine/param.h> #include <machine/spr.h> #include <machine/asm.h> #include <machine/vmparam.h> #ifdef _CALL_ELF .abiversion _CALL_ELF #endif /* Glue for linker script */ .globl kernbase .set kernbase, KERNBASE /* * Globals */ .data .align 3 GLOBAL(__startkernel) .llong begin GLOBAL(__endkernel) .llong end GLOBAL(can_wakeup) .llong 0x0 .align 4 #define TMPSTKSZ 16384 /* 16K temporary stack */ GLOBAL(tmpstk) .space TMPSTKSZ TOC_ENTRY(tmpstk) TOC_ENTRY(can_wakeup) #ifdef KDB #define TRAPSTKSZ 8192 /* 8k trap stack */ GLOBAL(trapstk) .space TRAPSTKSZ TOC_ENTRY(trapstk) #endif /* * Entry point for bootloaders that do not fully implement ELF and start * at the beginning of the image (kexec, notably). In its own section so * that it ends up before any linker-generated call stubs and actually at * the beginning of the image. kexec on some systems also enters at * (start of image) + 0x60, so put a spin loop there. */ .section ".text.kboot", "x", @progbits kbootentry: #ifdef __LITTLE_ENDIAN__ RETURN_TO_NATIVE_ENDIAN #endif b __start . = kbootentry + 0x40 /* Magic address used in platform layer */ .global smp_spin_sem ap_kexec_spin_sem: .long -1 . = kbootentry + 0x60 /* Entry point for kexec APs */ ap_kexec_start: /* At 0x60 past start, copied to 0x60 by kexec */ /* r3 set to CPU ID by kexec */ /* Invalidate icache for low-memory copy and jump there */ li %r0,0x80 dcbst 0,%r0 sync icbi 0,%r0 isync ba 0x80 /* Absolute branch to next inst */ . = kbootentry + 0x80 /* Aligned to cache line */ 1: or 31,31,31 /* yield */ sync lwz %r1,0x40(0) /* Spin on ap_kexec_spin_sem */ cmpw %r1,%r3 /* Until it equals our CPU ID */ bne 1b /* Released */ or 2,2,2 /* unyield */ /* Make sure that it will be software reset. Clear SRR1 */ li %r1,0 mtsrr1 %r1 ba EXC_RST /* * Now start the real text section */ .text .globl btext btext: /* * Main kernel entry point. * * Calling convention: * r3: Flattened Device Tree pointer (or zero) * r4: ignored * r5: OF client interface pointer (or zero) * r6: Loader metadata pointer (or zero) * r7: Magic cookie (0xfb5d104d) to indicate that r6 has loader metadata */ .text _NAKED_ENTRY(__start) #ifdef __LITTLE_ENDIAN__ RETURN_TO_NATIVE_ENDIAN #endif /* Set 64-bit mode if not yet set before branching to C */ mfmsr %r20 li %r21,1 insrdi %r20,%r21,1,0 mtmsrd %r20 isync nop /* Make this block a multiple of 8 bytes */ /* Set up the TOC pointer */ b 0f .align 3 0: nop bl 1f .llong __tocbase + 0x8000 - . 1: mflr %r2 ld %r1,0(%r2) add %r2,%r1,%r2 /* Get load offset */ ld %r31,-0x8000(%r2) /* First TOC entry is TOC base */ subf %r31,%r31,%r2 /* Subtract from real TOC base to get base */ /* Set up the stack pointer */ bl 1f .llong tmpstk + TMPSTKSZ - 96 - . 1: mflr %r30 ld %r1,0(%r30) add %r1,%r1,%r30 nop /* Relocate kernel */ std %r3,48(%r1) std %r4,56(%r1) std %r5,64(%r1) std %r6,72(%r1) std %r7,80(%r1) bl 1f .llong _DYNAMIC-. 1: mflr %r3 ld %r4,0(%r3) add %r3,%r4,%r3 mr %r4,%r31 bl elf_reloc_self nop ld %r3,48(%r1) ld %r4,56(%r1) ld %r5,64(%r1) ld %r6,72(%r1) ld %r7,80(%r1) /* Begin CPU init */ mr %r4,%r2 /* Replace ignored r4 with tocbase for trap handlers */ bl powerpc_init nop /* Set stack pointer to new value and branch to mi_startup */ mr %r1, %r3 li %r3, 0 std %r3, 0(%r1) bl mi_startup nop /* Unreachable */ b . _END(__start) ASENTRY_NOPROF(__restartkernel_virtual) /* * When coming in via this entry point, we need to alter the SLB to * shadow the segment register emulation entries in DMAP space. * We need to do this dance because we are running with virtual-mode * OpenFirmware and have not yet taken over the MMU. * * Assumptions: * 1) The kernel is currently identity-mapped. * 2) We are currently executing at an address compatible with * real mode. * 3) The first 16 SLB entries are emulating SRs. * 4) The rest of the SLB is not in use. * 5) OpenFirmware is not manipulating the SLB at runtime. * 6) We are running on 64-bit AIM. * * Tested on a G5. */ mfmsr %r14 /* Switch to real mode because we are about to mess with the SLB. */ andi. %r14, %r14, ~(PSL_DR|PSL_IR|PSL_ME|PSL_RI)@l mtmsr %r14 isync /* Prepare variables for later use. */ li %r14, 0 li %r18, 0 oris %r18, %r18, 0xc000 sldi %r18, %r18, 32 /* r18: 0xc000000000000000 */ 1: /* * Loop over the first 16 SLB entries. * Offset the SLBE into the DMAP, add 16 to the index, and write * it back to the SLB. */ /* XXX add more safety checks */ slbmfev %r15, %r14 slbmfee %r16, %r14 or %r16, %r16, %r14 /* index is 0-15 */ ori %r16, %r16, 0x10 /* add 16 to index. */ or %r16, %r16, %r18 /* SLBE DMAP offset */ rldicr %r17, %r16, 0, 37 /* Invalidation SLBE */ isync slbie %r17 /* isync */ slbmte %r15, %r16 isync addi %r14, %r14, 1 cmpdi %r14, 16 blt 1b /* * Now that we are set up with a temporary direct map, we can * continue with __restartkernel. Translation will be switched * back on at the rfid, at which point we will be executing from * the temporary direct map we just installed, until the kernel * takes over responsibility for the MMU. */ bl __restartkernel nop ASEND(__restartkernel_virtual) ASENTRY_NOPROF(__restartkernel) /* * r3-r7: arguments to go to __start * r8: offset from current kernel address to apply * r9: MSR to set when (atomically) jumping to __start + r8 */ mtsrr1 %r9 bl 1f 1: mflr %r25 add %r25,%r8,%r25 addi %r25,%r25,2f-1b mtsrr0 %r25 rfid 2: bl __start nop ASEND(__restartkernel) #include <powerpc/aim/trap_subr64.S>
