/* $OpenBSD: locore.S,v 1.9 1999/09/27 19:13:22 smurph Exp $ */ /* * Copyright (c) 1998 Steve Murphree, Jr. * Copyright (c) 1996 Nivas Madhur * 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. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by Nivas Madhur. * 4. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission * * 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 THE AUTHOR 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. * */ /* * Mach Operating System * Copyright (c) 1993-1991 Carnegie Mellon University * Copyright (c) 1991 OMRON Corporation * All Rights Reserved. * * Permission to use, copy, modify and distribute this software and its * documentation is hereby granted, provided that both the copyright * notice and this permission notice appear in all copies of the * software, derivative works or modified versions, and any portions * thereof, and that both notices appear in supporting documentation. * * CARNEGIE MELLON AND OMRON ALLOW FREE USE OF THIS SOFTWARE IN ITS "AS IS" * CONDITION. CARNEGIE MELLON AND OMRON DISCLAIM ANY LIABILITY OF ANY KIND * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. * * Carnegie Mellon requests users of this software to return to * * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU * School of Computer Science * Carnegie Mellon University * Pittsburgh PA 15213-3890 * * any improvements or extensions that they make and grant Carnegie the * rights to redistribute these changes. */ #ifndef ASSEMBLER #define ASSEMBLER #endif #include "assym.s" #include "machine/asm.h" #include "machine/trap.h" #include "machine/m88100.h" #include "machine/psl.h" #include "machine/vmparam.h" /* INTSTACK_SIZE */ /***********************************************************************/ #ifndef UADDR #define UADDR 0xEEE00000 /* address of u */ #endif /* UADDR */ /* * The memory looks like: * 0x00000 - 0x01000 : trap vectors * 0x01000 - 0x10000 : first 64k used by BUG * 0x10000 == start : Boot loader jumps here. (for now, this can * handle only NMAGIC - screwy linker) * ***********************************************************************/ text LABEL(_kernelstart) LABEL(_kernel_text) LABEL(_start) LABEL(start) br _start_text br _start_text br _start_text br _start_text ENTRY(doboot) /* * Try hitting the SRST bit in VMEchip2 to reset the system. */ #ifdef MVME188 /* check if it's a mvme188 */ or.u r4, r0, hi16(_cputyp) ld r3, r4, lo16(_cputyp) cmp r4, r3, 0x188 bb1 ne, r4, 1f bsr _m188_reset br m188_doboot_fail #endif /* MVME188 */ 1: or.u r3,r0, 0xfff4 ld r4,r3, 0x0060 /* read offset (LCSR +0x60) */ set r4,r4,1<23> /* set SYSRST bit - bit 23 */ st r4,r3, 0x0060 /* and store it back */ /* * We will be here if the reset above failed. In this case, * we will try to return to bug. * * Switch to interrupt stack and call __doboot to take care * going to BUG. Need to do this since __doboot turns off the * the MMU and we need to be on a 1-to-1 mapped stack so that * further calls don't get data access exceptions. */ /* Should we use idle_u instead? XXX nivas */ m188_doboot_fail: or.u r31, r0, hi16(_intstack_end) or r31, r31, lo16(_intstack_end) clr r31, r31, 3<0> /* round down to 8-byte boundary */ bsr __doboot /*NOTREACHED*/ /**************************************************************************/ LABEL(_start_text) /* This is the *real* start upon poweron or reset */ /* * Args passed by boot loader * r2 howto * r3 boot controler address * r4 esym * r5 start of mini * r6 end miniroot * r7 ((Clun << 8) ; Dlun & FF) -> bootdev * r8 cpu type (0x187, 0x188, 1x197) */ /* * (*entry)(flag, bugargs.ctrl_addr, cp, kernel.smini, * kernel.emini, bootdev, cputyp); */ or.u r13, r0, hi16(_boothowto) st r2, r13, lo16(_boothowto) or.u r13, r0, hi16(_bootaddr) st r3, r13, lo16(_bootaddr) or.u r13, r0, hi16(_first_addr) st r4, r13, lo16(_first_addr) or.u r13, r0, hi16(_esym) st r4, r13, lo16(_esym) or.u r13, r0, hi16(_miniroot) st r5, r13, lo16(_miniroot) or.u r13, r0, hi16(_bootdev) st r7, r13, lo16(_bootdev) or.u r13, r0, hi16(_cputyp) st r8, r13, lo16(_cputyp) /* * CPU Initialization * * Every CPU starts from here.. * (well, from 'start' above, which just jumps here). * * I use r11 and r22 here 'cause they're easy to not * get mixed up -- r10, for example, looks too similar * to r0 when not being careful.... * * Ensure that the PSR is as we like: * supervisor mode * big-endian byte ordering * concurrent operation allowed * carry bit clear (I don't think we really care about this) * FPU enabled * misaligned access raises an exception * interrupts disabled * shadow registers frozen * * The manual says not to disable interrupts and freeze shadowing * at the same time because interupts are not actually disabled * until after the next instruction. Well, if an interrupt * occurs now, we're in deep anyway, so I'm going to do * the two together. * * Upon a reset (or poweron, I guess), the PSR indicates: * supervisor mode * interrupts, shadowing, FPU, missaligned exception: all disabled * * We'll just construct our own turning on what we want. * * jfriedl@omron.co.jp */ cmp r2, r8, 0x197 /* r8 contains cputyp */ bb1 eq, r2, 1f /* if it's a '197, skip SSBR */ stcr r0, SSBR /* clear this for later */ 1: stcr r0, SR0 /* clear "current thread" */ stcr r0, SR1 /* clear the CPU flags */ set r11, r0, 1 set r11, r11, 1 set r11, r11, 1<4> set r11, r11, 1<29> set r11, r11, 1<25> stcr r11, PSR stcr r0, VBR /* set Vector Base Register to 0, ALWAYS! */ FLUSH_PIPELINE cmp r2, r8, 0x197 /* r8 contains cputyp */ bb1 eq, r2, master_start /* if it's a '197, skip to master_start */ #if 0 /* clear BSS. Boot loader might have already done this... */ or.u r2, r0, hi16(_edata) or r2, r2, lo16(_edata) or.u r4, r0, hi16(_end) or r4, r4, lo16(_end) bsr.n _bzero /* bzero(edata, end-edata) */ subu r3, r4, r2 #endif /* * First time to count how many CPUs to attach */ or.u r11, r0, hi16(initialized_cpu_lock) or r11, r11, lo16(initialized_cpu_lock) _LABEL(check_init_lock) FLUSH_PIPELINE or r22, r0, 1 xmem r22, r11, r0 /* If r22 gets 0, we have the lock.. */ bcnd eq0, r22, have_init_lock/* ..but if not, we must wait */ _LABEL(wait_for_init_lock) /* just watch the lock until it looks clear */ ld r22, r11, r0 bcnd eq0, r22, check_init_lock br wait_for_init_lock /* looks clear -- try to grab */ _LABEL(have_init_lock) FLUSH_PIPELINE or.u r11, r0, hi16(_initialized_cpus) ld r22, r11, lo16(_initialized_cpus) add r23, r22, 1 st r23, r11, lo16(_initialized_cpus) or.u r11, r0, hi16(initialized_cpu_lock) st r0, r11, lo16(initialized_cpu_lock) /* * Now we vie with any other processors to see who's the master. * We first try to obtain a lock to see who's allowed * to check/set the master lock. */ or.u r11, r0, hi16(_inter_processor_lock) or r11, r11, lo16(_inter_processor_lock) _LABEL(check_ip_lock) FLUSH_PIPELINE or r22, r0, 1 xmem r22, r11, r0 /* If r22 gets 0, we have the lock.. */ bcnd eq0, r22, have_ip_lock /* ..but if not, we must wait */ _LABEL(wait_for_ip_lock) /* just watch the lock until it looks clear */ ld r22, r11, r0 bcnd ne0, r22, wait_for_ip_lock /* since we can be here with caches off, add a few nops to keep the bus from getting overloaded */ or r2, r0, lo16(1000) _LABEL(ip_loop) subu r2, r2, 1 bcnd eq0, r2, ip_loop br check_ip_lock /* looks clear -- try to grab */ _LABEL(have_ip_lock) /* now try to grab the master_processor_chosen prize */ FLUSH_PIPELINE or.u r11, r0, hi16(master_processor_chosen) or r11, r11, lo16(master_processor_chosen) or r22, r0, 1 xmem r22, r11, r0 /* * If r22 is not clear we're a slave, * otherwise we're first and the master. * * Note that we haven't released the interprocessor lock.... * We'll do that when we're ready for another CPU to go. * (if we're the master, we'll do that in master_start below. * if we're a slave, we'll do it in slave_start below). */ bcnd ne0, r22, slave_start /* fall through to master start if that's appropriate */ _LABEL(master_start) /* * Switch to interrupt stack * Use idle_u's stack instead? */ or.u r31, r0, hi16(_intstack_end) or r31, r31, lo16(_intstack_end) clr r31, r31, 3<0> /* round down to 8-byte boundary */ #ifdef MVME197 cmp r2, r8, 0x197 /* r8 contains cputyp */ bb1 ne, r2, 1f /* if it's a '197, use different vectors */ or.u r3, r0, hi16(_m197_vector_list) or r3, r3, lo16(_m197_vector_list) bsr.n _vector_init ldcr r2, VBR br 2f #endif /* MVME197 */ 1: #if defined(MVME187) || defined(MVME188) /* * Want to make the call: * vector_init(VBR, vector_list) */ or.u r3, r0, hi16(_vector_list) or r3, r3, lo16(_vector_list) bsr.n _vector_init ldcr r2, VBR #endif /* defined(MVME187) || defined(MVME188) */ 2: /* still on int stack */ bsr.n _mvme_bootstrap subu r31, r31, 40 addu r31, r31, 40 /* we now know our cpu number, so we * can set interrupt_stack[cpu_number()] = _intstack */ ldcr r10, SR1 mak r10, r10, FLAG_CPU_FIELD_WIDTH<0> /* r10 <-- CPU# */ /* figure interrupt_stack[cpu_number()] */ or.u r11, r0, hi16(_interrupt_stack) or r11, r11, lo16(_interrupt_stack) or.u r12, r0, hi16(_intstack) or r12, r12, lo16(_intstack) st r12, r11 [r10] /* switch to proc0 uarea */ or.u r10, r0, hi16(UADDR) or r31, r10,lo16(UADDR) addu r31, r31, USIZE - 8 /* make the call: main() */ or.u r2, r0, hi16(UADDR) or r2, r2,lo16(UADDR) addu r2, r2, USIZE - 8 subu r31, r31, 40 bsr _main addu r31, r31, 40 bsr _panic /*********************************************************************** * slave CPUs starts here */ _LABEL(slave_start) /* while holding the inter_processor_lock, the slave cpu can find use the slavestack to call slave_pre_main and determine its cpu number. After that, however, it should switch over to the interrupt stack associated with its cpu */ /* r31 <-- slavestack */ or.u r31, r0, hi16(_slavestack_end) or r31, r31, lo16(_slavestack_end) clr r31, r31, 3<0> /* round down to 8-byte boundary */ bsr.n _slave_pre_main /* set cpu number */ subu r31, r31, 48 /* allocate frame */ bsr _get_slave_stack addu r31, r2, INTSTACK_SIZE + 4096 /* SR1 now contains our cpu number. We can now release the inter_processor_lock, as we are done with the slavestack. We also have an interrupt stack */ or.u r10, r0, hi16(_inter_processor_lock) st r0, r10, lo16(_inter_processor_lock) br.n _slave_main /* does not return */ subu r31, r31, 40 /* allocate frame */ _LABEL(_spin_cpu) or.u r3, r0, hi16(_start_text) or r3, r3, lo16(_start_text) or r9, r0, 0x100 /* .FORKMPU */ tb0 0, r0, 0x200-16 /* call 188Bug */ jmp r1 /*****************************************************************************/ data .align 4096 /* VBR points to page aligned list */ global _vector_list, _vector_list_end #if defined(MVME187) || defined(MVME188) _vector_list: /* references memory BELOW this line */ #include "machine/exception_vectors.h" _vector_list_end: word END_OF_VECTOR_LIST #endif /* defined(MVME187) || defined(MVME188) */ #ifdef MVME197 global _vector_list, _vector_list_end _m197_vector_list: /* references memory BELOW this line */ #include "machine/exception_vectors2.h" _m197_vector_list_end: word END_OF_VECTOR_LIST #endif /* MVME197 */ .align 4096 /* Vector table is a page aligned list */ LABEL(_vector_table) /* new vector table location, was addr 0 */ space (0x1000) /* 16K */ .align 4096 /* SDT (segment descriptor table */ global _kernel_sdt _kernel_sdt: space (0x2000) /* 8K - 4K phys, 4K virt*/ global _ret_addr _ret_addr: word 0 global _msgsw _msgsw: word 0 /* Bits here turn on/off debugging somewhere */ _LABEL(initialized_cpu_lock) /* XMEM spin lock -- to count CPUs */ word 0 LABEL(_initialized_cpus) /* CPU counter to initialize */ word 0 _LABEL(master_processor_chosen) /* The first processor that XMEMs this becomes the master */ word 0 LABEL(_inter_processor_lock) /* XMEM spin lock -- controls access to master_processor_chosen */ word 0 .align 4096 global _intstack, _intstack_end, _slavestack, _slavestack_end _intstack: space (4 * NBPG) /* 16K, just to be safe */ _intstack_end: _slavestack: space (NBPG) /* 4K, small, interim stack */ _slavestack_end: /* * When a process exits and its u. area goes away, we set curpcb to point * to this `u.', leaving us with something to use for an interrupt stack, * and letting all the register save code have a pcb_uw to examine. * This is also carefully arranged (to come just before u0, so that * process 0's kernel stack can quietly overrun into it during bootup, if * we feel like doing that). * Should be page aligned. */ .align 4096 global _idle_u _idle_u: space UPAGES * NBPG /* * Process 0's u. * * This must be page aligned */ .align 4096 global _u0 _u0: space UPAGES * NBPG estack0: /* * UPAGES get mapped to kstack */ global _kstack _kstack: word UADDR #ifdef DDB global _esym _esym: word 0 #endif /* DDB */ global _intiobase, _intiolimit, _extiobase _intiobase: word 0 | KVA of base of internal IO space _intiolimit: word 0 | KVA of end of internal IO space _extiobase: word 0 | KVA of base of external IO space global _proc0paddr /* move to C code */ _proc0paddr: word _u0 /* KVA of proc0 uarea */ /* * _curpcb points to the current pcb (and hence u. area). * Initially this is the special one. */ /* * pcb is composed of kernel state + user state * I may have to change curpcb to u0 + PCB_USER based on what * other parts expect XXX nivas */ global _curpcb /* move to C code */ _curpcb: word _u0 /* curpcb = &u0 */ /* * Trampoline code. Gets copied to the top of * user stack in exec. */ global _sigcode _sigcode: /* r31 points to sigframe */ ld r2, r31, 0 /* signo */ ld r3, r31, 4 /* siginfo_t* */ ld r4, r31, 8 /* sigcontext* */ ld r5, r31, 12 /* handler */ jsr.n r5 subu r31, r31, 40 /* give some stack space */ addu r31, r31, 40 /* restore old sp value */ ld r2, r31, 8 /* sigcontext* */ or r13, r0, SYS_sigreturn tb0 0, r0, 128 /* syscall trap, calling sigreturn */ or r0, r0, 0 or r0, r0, 0 /* sigreturn will not return unless it fails */ or r13, r0, SYS_exit tb0 0, r0, 128 /* syscall trap, exit */ or r0, r0, 0 or r0, r0, 0 global _esigcode _esigcode: