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Diffstat (limited to 'arch/powerpc/kernel/misc_64.S')
| -rw-r--r-- | arch/powerpc/kernel/misc_64.S | 950 |
1 files changed, 950 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S new file mode 100644 index 000000000000..ae48a002f81a --- /dev/null +++ b/arch/powerpc/kernel/misc_64.S @@ -0,0 +1,950 @@ +/* + * 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___do_IRQ) + mflr r0 + std r0,16(r1) + stdu r1,THREAD_SIZE-112(r5) + mr r1,r5 + bl .__do_IRQ + 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) */ + +/* + * SCOM access functions for 970 (FX only for now) + * + * unsigned long scom970_read(unsigned int address); + * void scom970_write(unsigned int address, unsigned long value); + * + * The address passed in is the 24 bits register address. This code + * is 970 specific and will not check the status bits, so you should + * know what you are doing. + */ +_GLOBAL(scom970_read) + /* interrupts off */ + mfmsr r4 + ori r0,r4,MSR_EE + xori r0,r0,MSR_EE + mtmsrd r0,1 + + /* rotate 24 bits SCOM address 8 bits left and mask out it's low 8 bits + * (including parity). On current CPUs they must be 0'd, + * and finally or in RW bit + */ + rlwinm r3,r3,8,0,15 + ori r3,r3,0x8000 + + /* do the actual scom read */ + sync + mtspr SPRN_SCOMC,r3 + isync + mfspr r3,SPRN_SCOMD + isync + mfspr r0,SPRN_SCOMC + isync + + /* XXX: fixup result on some buggy 970's (ouch ! we lost a bit, bah + * that's the best we can do). Not implemented yet as we don't use + * the scom on any of the bogus CPUs yet, but may have to be done + * ultimately + */ + + /* restore interrupts */ + mtmsrd r4,1 + blr + + +_GLOBAL(scom970_write) + /* interrupts off */ + mfmsr r5 + ori r0,r5,MSR_EE + xori r0,r0,MSR_EE + mtmsrd r0,1 + + /* rotate 24 bits SCOM address 8 bits left and mask out it's low 8 bits + * (including parity). On current CPUs they must be 0'd. + */ + + rlwinm r3,r3,8,0,15 + + sync + mtspr SPRN_SCOMD,r4 /* write data */ + isync + mtspr SPRN_SCOMC,r3 /* write command */ + isync + mfspr 3,SPRN_SCOMC + isync + + /* restore interrupts */ + mtmsrd r5,1 + blr + + +/* + * 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 */ |