/* * arch/powerpc/kernel/misc64.S * * This file contains miscellaneous low-level functions. * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) * * Largely rewritten by Cort Dougan (cort@cs.nmt.edu) * and Paul Mackerras. * Adapted for iSeries by Mike Corrigan (mikejc@us.ibm.com) * PPC64 updates by Dave Engebretsen (engebret@us.ibm.com) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * */ #include <linux/config.h> #include <linux/sys.h> #include <asm/unistd.h> #include <asm/errno.h> #include <asm/processor.h> #include <asm/page.h> #include <asm/cache.h> #include <asm/ppc_asm.h> #include <asm/asm-offsets.h> #include <asm/cputable.h> #include <asm/thread_info.h> .text /* * Returns (address we are running at) - (address we were linked at) * for use before the text and data are mapped to KERNELBASE. */ _GLOBAL(reloc_offset) mflr r0 bl 1f 1: mflr r3 LOADADDR(r4,1b) subf r3,r4,r3 mtlr r0 blr /* * add_reloc_offset(x) returns x + reloc_offset(). */ _GLOBAL(add_reloc_offset) mflr r0 bl 1f 1: mflr r5 LOADADDR(r4,1b) subf r5,r4,r5 add r3,r3,r5 mtlr r0 blr _GLOBAL(get_msr) mfmsr r3 blr _GLOBAL(get_dar) mfdar r3 blr _GLOBAL(get_srr0) mfsrr0 r3 blr _GLOBAL(get_srr1) mfsrr1 r3 blr _GLOBAL(get_sp) mr r3,r1 blr #ifdef CONFIG_IRQSTACKS _GLOBAL(call_do_softirq) mflr r0 std r0,16(r1) stdu r1,THREAD_SIZE-112(r3) mr r1,r3 bl .__do_softirq ld r1,0(r1) ld r0,16(r1) mtlr r0 blr _GLOBAL(call_handle_IRQ_event) mflr r0 std r0,16(r1) stdu r1,THREAD_SIZE-112(r6) mr r1,r6 bl .handle_IRQ_event ld r1,0(r1) ld r0,16(r1) mtlr r0 blr #endif /* CONFIG_IRQSTACKS */ /* * To be called by C code which needs to do some operations with MMU * disabled. Note that interrupts have to be disabled by the caller * prior to calling us. The code called _MUST_ be in the RMO of course * and part of the linear mapping as we don't attempt to translate the * stack pointer at all. The function is called with the stack switched * to this CPU emergency stack * * prototype is void *call_with_mmu_off(void *func, void *data); * * the called function is expected to be of the form * * void *called(void *data); */ _GLOBAL(call_with_mmu_off) mflr r0 /* get link, save it on stackframe */ std r0,16(r1) mr r1,r5 /* save old stack ptr */ ld r1,PACAEMERGSP(r13) /* get emerg. stack */ subi r1,r1,STACK_FRAME_OVERHEAD std r0,16(r1) /* save link on emerg. stack */ std r5,0(r1) /* save old stack ptr in backchain */ ld r3,0(r3) /* get to real function ptr (assume same TOC) */ bl 2f /* we need LR to return, continue at label 2 */ ld r0,16(r1) /* we return here from the call, get LR and */ ld r1,0(r1) /* .. old stack ptr */ mtspr SPRN_SRR0,r0 /* and get back to virtual mode with these */ mfmsr r4 ori r4,r4,MSR_IR|MSR_DR mtspr SPRN_SRR1,r4 rfid 2: mtspr SPRN_SRR0,r3 /* coming from above, enter real mode */ mr r3,r4 /* get parameter */ mfmsr r0 ori r0,r0,MSR_IR|MSR_DR xori r0,r0,MSR_IR|MSR_DR mtspr SPRN_SRR1,r0 rfid .section ".toc","aw" PPC64_CACHES: .tc ppc64_caches[TC],ppc64_caches .section ".text" /* * Write any modified data cache blocks out to memory * and invalidate the corresponding instruction cache blocks. * * flush_icache_range(unsigned long start, unsigned long stop) * * flush all bytes from start through stop-1 inclusive */ _KPROBE(__flush_icache_range) /* * Flush the data cache to memory * * Different systems have different cache line sizes * and in some cases i-cache and d-cache line sizes differ from * each other. */ ld r10,PPC64_CACHES@toc(r2) lwz r7,DCACHEL1LINESIZE(r10)/* Get cache line size */ addi r5,r7,-1 andc r6,r3,r5 /* round low to line bdy */ subf r8,r6,r4 /* compute length */ add r8,r8,r5 /* ensure we get enough */ lwz r9,DCACHEL1LOGLINESIZE(r10) /* Get log-2 of cache line size */ srw. r8,r8,r9 /* compute line count */ beqlr /* nothing to do? */ mtctr r8 1: dcbst 0,r6 add r6,r6,r7 bdnz 1b sync /* Now invalidate the instruction cache */ lwz r7,ICACHEL1LINESIZE(r10) /* Get Icache line size */ addi r5,r7,-1 andc r6,r3,r5 /* round low to line bdy */ subf r8,r6,r4 /* compute length */ add r8,r8,r5 lwz r9,ICACHEL1LOGLINESIZE(r10) /* Get log-2 of Icache line size */ srw. r8,r8,r9 /* compute line count */ beqlr /* nothing to do? */ mtctr r8 2: icbi 0,r6 add r6,r6,r7 bdnz 2b isync blr .previous .text /* * Like above, but only do the D-cache. * * flush_dcache_range(unsigned long start, unsigned long stop) * * flush all bytes from start to stop-1 inclusive */ _GLOBAL(flush_dcache_range) /* * Flush the data cache to memory * * Different systems have different cache line sizes */ ld r10,PPC64_CACHES@toc(r2) lwz r7,DCACHEL1LINESIZE(r10) /* Get dcache line size */ addi r5,r7,-1 andc r6,r3,r5 /* round low to line bdy */ subf r8,r6,r4 /* compute length */ add r8,r8,r5 /* ensure we get enough */ lwz r9,DCACHEL1LOGLINESIZE(r10) /* Get log-2 of dcache line size */ srw. r8,r8,r9 /* compute line count */ beqlr /* nothing to do? */ mtctr r8 0: dcbst 0,r6 add r6,r6,r7 bdnz 0b sync blr /* * Like above, but works on non-mapped physical addresses. * Use only for non-LPAR setups ! It also assumes real mode * is cacheable. Used for flushing out the DART before using * it as uncacheable memory * * flush_dcache_phys_range(unsigned long start, unsigned long stop) * * flush all bytes from start to stop-1 inclusive */ _GLOBAL(flush_dcache_phys_range) ld r10,PPC64_CACHES@toc(r2) lwz r7,DCACHEL1LINESIZE(r10) /* Get dcache line size */ addi r5,r7,-1 andc r6,r3,r5 /* round low to line bdy */ subf r8,r6,r4 /* compute length */ add r8,r8,r5 /* ensure we get enough */ lwz r9,DCACHEL1LOGLINESIZE(r10) /* Get log-2 of dcache line size */ srw. r8,r8,r9 /* compute line count */ beqlr /* nothing to do? */ mfmsr r5 /* Disable MMU Data Relocation */ ori r0,r5,MSR_DR xori r0,r0,MSR_DR sync mtmsr r0 sync isync mtctr r8 0: dcbst 0,r6 add r6,r6,r7 bdnz 0b sync isync mtmsr r5 /* Re-enable MMU Data Relocation */ sync isync blr _GLOBAL(flush_inval_dcache_range) ld r10,PPC64_CACHES@toc(r2) lwz r7,DCACHEL1LINESIZE(r10) /* Get dcache line size */ addi r5,r7,-1 andc r6,r3,r5 /* round low to line bdy */ subf r8,r6,r4 /* compute length */ add r8,r8,r5 /* ensure we get enough */ lwz r9,DCACHEL1LOGLINESIZE(r10)/* Get log-2 of dcache line size */ srw. r8,r8,r9 /* compute line count */ beqlr /* nothing to do? */ sync isync mtctr r8 0: dcbf 0,r6 add r6,r6,r7 bdnz 0b sync isync blr /* * Flush a particular page from the data cache to RAM. * Note: this is necessary because the instruction cache does *not* * snoop from the data cache. * * void __flush_dcache_icache(void *page) */ _GLOBAL(__flush_dcache_icache) /* * Flush the data cache to memory * * Different systems have different cache line sizes */ /* Flush the dcache */ ld r7,PPC64_CACHES@toc(r2) clrrdi r3,r3,PAGE_SHIFT /* Page align */ lwz r4,DCACHEL1LINESPERPAGE(r7) /* Get # dcache lines per page */ lwz r5,DCACHEL1LINESIZE(r7) /* Get dcache line size */ mr r6,r3 mtctr r4 0: dcbst 0,r6 add r6,r6,r5 bdnz 0b sync /* Now invalidate the icache */ lwz r4,ICACHEL1LINESPERPAGE(r7) /* Get # icache lines per page */ lwz r5,ICACHEL1LINESIZE(r7) /* Get icache line size */ mtctr r4 1: icbi 0,r3 add r3,r3,r5 bdnz 1b isync blr /* * I/O string operations * * insb(port, buf, len) * outsb(port, buf, len) * insw(port, buf, len) * outsw(port, buf, len) * insl(port, buf, len) * outsl(port, buf, len) * insw_ns(port, buf, len) * outsw_ns(port, buf, len) * insl_ns(port, buf, len) * outsl_ns(port, buf, len) * * The *_ns versions don't do byte-swapping. */ _GLOBAL(_insb) cmpwi 0,r5,0 mtctr r5 subi r4,r4,1 blelr- 00: lbz r5,0(r3) eieio stbu r5,1(r4) bdnz 00b twi 0,r5,0 isync blr _GLOBAL(_outsb) cmpwi 0,r5,0 mtctr r5 subi r4,r4,1 blelr- 00: lbzu r5,1(r4) stb r5,0(r3) bdnz 00b sync blr _GLOBAL(_insw) cmpwi 0,r5,0 mtctr r5 subi r4,r4,2 blelr- 00: lhbrx r5,0,r3 eieio sthu r5,2(r4) bdnz 00b twi 0,r5,0 isync blr _GLOBAL(_outsw) cmpwi 0,r5,0 mtctr r5 subi r4,r4,2 blelr- 00: lhzu r5,2(r4) sthbrx r5,0,r3 bdnz 00b sync blr _GLOBAL(_insl) cmpwi 0,r5,0 mtctr r5 subi r4,r4,4 blelr- 00: lwbrx r5,0,r3 eieio stwu r5,4(r4) bdnz 00b twi 0,r5,0 isync blr _GLOBAL(_outsl) cmpwi 0,r5,0 mtctr r5 subi r4,r4,4 blelr- 00: lwzu r5,4(r4) stwbrx r5,0,r3 bdnz 00b sync blr /* _GLOBAL(ide_insw) now in drivers/ide/ide-iops.c */ _GLOBAL(_insw_ns) cmpwi 0,r5,0 mtctr r5 subi r4,r4,2 blelr- 00: lhz r5,0(r3) eieio sthu r5,2(r4) bdnz 00b twi 0,r5,0 isync blr /* _GLOBAL(ide_outsw) now in drivers/ide/ide-iops.c */ _GLOBAL(_outsw_ns) cmpwi 0,r5,0 mtctr r5 subi r4,r4,2 blelr- 00: lhzu r5,2(r4) sth r5,0(r3) bdnz 00b sync blr _GLOBAL(_insl_ns) cmpwi 0,r5,0 mtctr r5 subi r4,r4,4 blelr- 00: lwz r5,0(r3) eieio stwu r5,4(r4) bdnz 00b twi 0,r5,0 isync blr _GLOBAL(_outsl_ns) cmpwi 0,r5,0 mtctr r5 subi r4,r4,4 blelr- 00: lwzu r5,4(r4) stw r5,0(r3) bdnz 00b sync blr /* * identify_cpu and calls setup_cpu * In: r3 = base of the cpu_specs array * r4 = address of cur_cpu_spec * r5 = relocation offset */ _GLOBAL(identify_cpu) mfpvr r7 1: lwz r8,CPU_SPEC_PVR_MASK(r3) and r8,r8,r7 lwz r9,CPU_SPEC_PVR_VALUE(r3) cmplw 0,r9,r8 beq 1f addi r3,r3,CPU_SPEC_ENTRY_SIZE b 1b 1: sub r0,r3,r5 std r0,0(r4) ld r4,CPU_SPEC_SETUP(r3) add r4,r4,r5 ld r4,0(r4) add r4,r4,r5 mtctr r4 /* Calling convention for cpu setup is r3=offset, r4=cur_cpu_spec */ mr r4,r3 mr r3,r5 bctr /* * do_cpu_ftr_fixups - goes through the list of CPU feature fixups * and writes nop's over sections of code that don't apply for this cpu. * r3 = data offset (not changed) */ _GLOBAL(do_cpu_ftr_fixups) /* Get CPU 0 features */ LOADADDR(r6,cur_cpu_spec) sub r6,r6,r3 ld r4,0(r6) sub r4,r4,r3 ld r4,CPU_SPEC_FEATURES(r4) /* Get the fixup table */ LOADADDR(r6,__start___ftr_fixup) sub r6,r6,r3 LOADADDR(r7,__stop___ftr_fixup) sub r7,r7,r3 /* Do the fixup */ 1: cmpld r6,r7 bgelr addi r6,r6,32 ld r8,-32(r6) /* mask */ and r8,r8,r4 ld r9,-24(r6) /* value */ cmpld r8,r9 beq 1b ld r8,-16(r6) /* section begin */ ld r9,-8(r6) /* section end */ subf. r9,r8,r9 beq 1b /* write nops over the section of code */ /* todo: if large section, add a branch at the start of it */ srwi r9,r9,2 mtctr r9 sub r8,r8,r3 lis r0,0x60000000@h /* nop */ 3: stw r0,0(r8) andi. r10,r4,CPU_FTR_SPLIT_ID_CACHE@l beq 2f dcbst 0,r8 /* suboptimal, but simpler */ sync icbi 0,r8 2: addi r8,r8,4 bdnz 3b sync /* additional sync needed on g4 */ isync b 1b #if defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_MAPLE) /* * Do an IO access in real mode */ _GLOBAL(real_readb) mfmsr r7 ori r0,r7,MSR_DR xori r0,r0,MSR_DR sync mtmsrd r0 sync isync mfspr r6,SPRN_HID4 rldicl r5,r6,32,0 ori r5,r5,0x100 rldicl r5,r5,32,0 sync mtspr SPRN_HID4,r5 isync slbia isync lbz r3,0(r3) sync mtspr SPRN_HID4,r6 isync slbia isync mtmsrd r7 sync isync blr /* * Do an IO access in real mode */ _GLOBAL(real_writeb) mfmsr r7 ori r0,r7,MSR_DR xori r0,r0,MSR_DR sync mtmsrd r0 sync isync mfspr r6,SPRN_HID4 rldicl r5,r6,32,0 ori r5,r5,0x100 rldicl r5,r5,32,0 sync mtspr SPRN_HID4,r5 isync slbia isync stb r3,0(r4) sync mtspr SPRN_HID4,r6 isync slbia isync mtmsrd r7 sync isync blr #endif /* defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_MAPLE) */ /* * Create a kernel thread * kernel_thread(fn, arg, flags) */ _GLOBAL(kernel_thread) std r29,-24(r1) std r30,-16(r1) stdu r1,-STACK_FRAME_OVERHEAD(r1) mr r29,r3 mr r30,r4 ori r3,r5,CLONE_VM /* flags */ oris r3,r3,(CLONE_UNTRACED>>16) li r4,0 /* new sp (unused) */ li r0,__NR_clone sc cmpdi 0,r3,0 /* parent or child? */ bne 1f /* return if parent */ li r0,0 stdu r0,-STACK_FRAME_OVERHEAD(r1) ld r2,8(r29) ld r29,0(r29) mtlr r29 /* fn addr in lr */ mr r3,r30 /* load arg and call fn */ blrl li r0,__NR_exit /* exit after child exits */ li r3,0 sc 1: addi r1,r1,STACK_FRAME_OVERHEAD ld r29,-24(r1) ld r30,-16(r1) blr /* * disable_kernel_fp() * Disable the FPU. */ _GLOBAL(disable_kernel_fp) mfmsr r3 rldicl r0,r3,(63-MSR_FP_LG),1 rldicl r3,r0,(MSR_FP_LG+1),0 mtmsrd r3 /* disable use of fpu now */ isync blr #ifdef CONFIG_ALTIVEC #if 0 /* this has no callers for now */ /* * disable_kernel_altivec() * Disable the VMX. */ _GLOBAL(disable_kernel_altivec) mfmsr r3 rldicl r0,r3,(63-MSR_VEC_LG),1 rldicl r3,r0,(MSR_VEC_LG+1),0 mtmsrd r3 /* disable use of VMX now */ isync blr #endif /* 0 */ /* * giveup_altivec(tsk) * Disable VMX for the task given as the argument, * and save the vector registers in its thread_struct. * Enables the VMX for use in the kernel on return. */ _GLOBAL(giveup_altivec) mfmsr r5 oris r5,r5,MSR_VEC@h mtmsrd r5 /* enable use of VMX now */ isync cmpdi 0,r3,0 beqlr- /* if no previous owner, done */ addi r3,r3,THREAD /* want THREAD of task */ ld r5,PT_REGS(r3) cmpdi 0,r5,0 SAVE_32VRS(0,r4,r3) mfvscr vr0 li r4,THREAD_VSCR stvx vr0,r4,r3 beq 1f ld r4,_MSR-STACK_FRAME_OVERHEAD(r5) lis r3,MSR_VEC@h andc r4,r4,r3 /* disable FP for previous task */ std r4,_MSR-STACK_FRAME_OVERHEAD(r5) 1: #ifndef CONFIG_SMP li r5,0 ld r4,last_task_used_altivec@got(r2) std r5,0(r4) #endif /* CONFIG_SMP */ blr #endif /* CONFIG_ALTIVEC */ _GLOBAL(__setup_cpu_power3) blr _GLOBAL(execve) li r0,__NR_execve sc bnslr neg r3,r3 blr /* kexec_wait(phys_cpu) * * wait for the flag to change, indicating this kernel is going away but * the slave code for the next one is at addresses 0 to 100. * * This is used by all slaves. * * Physical (hardware) cpu id should be in r3. */ _GLOBAL(kexec_wait) bl 1f 1: mflr r5 addi r5,r5,kexec_flag-1b 99: HMT_LOW #ifdef CONFIG_KEXEC /* use no memory without kexec */ lwz r4,0(r5) cmpwi 0,r4,0 bnea 0x60 #endif b 99b /* this can be in text because we won't change it until we are * running in real anyways */ kexec_flag: .long 0 #ifdef CONFIG_KEXEC /* kexec_smp_wait(void) * * call with interrupts off * note: this is a terminal routine, it does not save lr * * get phys id from paca * set paca id to -1 to say we got here * switch to real mode * join other cpus in kexec_wait(phys_id) */ _GLOBAL(kexec_smp_wait) lhz r3,PACAHWCPUID(r13) li r4,-1 sth r4,PACAHWCPUID(r13) /* let others know we left */ bl real_mode b .kexec_wait /* * switch to real mode (turn mmu off) * we use the early kernel trick that the hardware ignores bits * 0 and 1 (big endian) of the effective address in real mode * * don't overwrite r3 here, it is live for kexec_wait above. */ real_mode: /* assume normal blr return */ 1: li r9,MSR_RI li r10,MSR_DR|MSR_IR mflr r11 /* return address to SRR0 */ mfmsr r12 andc r9,r12,r9 andc r10,r12,r10 mtmsrd r9,1 mtspr SPRN_SRR1,r10 mtspr SPRN_SRR0,r11 rfid /* * kexec_sequence(newstack, start, image, control, clear_all()) * * does the grungy work with stack switching and real mode switches * also does simple calls to other code */ _GLOBAL(kexec_sequence) mflr r0 std r0,16(r1) /* switch stacks to newstack -- &kexec_stack.stack */ stdu r1,THREAD_SIZE-112(r3) mr r1,r3 li r0,0 std r0,16(r1) /* save regs for local vars on new stack. * yes, we won't go back, but ... */ std r31,-8(r1) std r30,-16(r1) std r29,-24(r1) std r28,-32(r1) std r27,-40(r1) std r26,-48(r1) std r25,-56(r1) stdu r1,-112-64(r1) /* save args into preserved regs */ mr r31,r3 /* newstack (both) */ mr r30,r4 /* start (real) */ mr r29,r5 /* image (virt) */ mr r28,r6 /* control, unused */ mr r27,r7 /* clear_all() fn desc */ mr r26,r8 /* spare */ lhz r25,PACAHWCPUID(r13) /* get our phys cpu from paca */ /* disable interrupts, we are overwriting kernel data next */ mfmsr r3 rlwinm r3,r3,0,17,15 mtmsrd r3,1 /* copy dest pages, flush whole dest image */ mr r3,r29 bl .kexec_copy_flush /* (image) */ /* turn off mmu */ bl real_mode /* clear out hardware hash page table and tlb */ ld r5,0(r27) /* deref function descriptor */ mtctr r5 bctrl /* ppc_md.hash_clear_all(void); */ /* * kexec image calling is: * the first 0x100 bytes of the entry point are copied to 0 * * all slaves branch to slave = 0x60 (absolute) * slave(phys_cpu_id); * * master goes to start = entry point * start(phys_cpu_id, start, 0); * * * a wrapper is needed to call existing kernels, here is an approximate * description of one method: * * v2: (2.6.10) * start will be near the boot_block (maybe 0x100 bytes before it?) * it will have a 0x60, which will b to boot_block, where it will wait * and 0 will store phys into struct boot-block and load r3 from there, * copy kernel 0-0x100 and tell slaves to back down to 0x60 again * * v1: (2.6.9) * boot block will have all cpus scanning device tree to see if they * are the boot cpu ????? * other device tree differences (prop sizes, va vs pa, etc)... */ /* copy 0x100 bytes starting at start to 0 */ li r3,0 mr r4,r30 li r5,0x100 li r6,0 bl .copy_and_flush /* (dest, src, copy limit, start offset) */ 1: /* assume normal blr return */ /* release other cpus to the new kernel secondary start at 0x60 */ mflr r5 li r6,1 stw r6,kexec_flag-1b(5) mr r3,r25 # my phys cpu mr r4,r30 # start, aka phys mem offset mtlr 4 li r5,0 blr /* image->start(physid, image->start, 0); */ #endif /* CONFIG_KEXEC */