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Diffstat (limited to 'arch/powerpc/kernel/misc_64.S')
| -rw-r--r-- | arch/powerpc/kernel/misc_64.S | 497 |
1 files changed, 497 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S new file mode 100644 index 000000000..1a8cdafd6 --- /dev/null +++ b/arch/powerpc/kernel/misc_64.S @@ -0,0 +1,497 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * 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) + */ + +#include <linux/export.h> +#include <linux/linkage.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> +#include <asm/kexec.h> +#include <asm/ptrace.h> +#include <asm/mmu.h> +#include <asm/feature-fixups.h> + + .text + +_GLOBAL(__bswapdi2) +EXPORT_SYMBOL(__bswapdi2) + srdi r8,r3,32 + rlwinm r7,r3,8,0xffffffff + rlwimi r7,r3,24,0,7 + rlwinm r9,r8,8,0xffffffff + rlwimi r7,r3,24,16,23 + rlwimi r9,r8,24,0,7 + rlwimi r9,r8,24,16,23 + sldi r7,r7,32 + or r3,r7,r9 + blr + + +#ifdef CONFIG_PPC_EARLY_DEBUG_BOOTX +_GLOBAL(rmci_on) + sync + isync + li r3,0x100 + rldicl r3,r3,32,0 + mfspr r5,SPRN_HID4 + or r5,r5,r3 + sync + mtspr SPRN_HID4,r5 + isync + slbia + isync + sync + blr + +_GLOBAL(rmci_off) + sync + isync + li r3,0x100 + rldicl r3,r3,32,0 + mfspr r5,SPRN_HID4 + andc r5,r5,r3 + sync + mtspr SPRN_HID4,r5 + isync + slbia + isync + sync + blr +#endif /* CONFIG_PPC_EARLY_DEBUG_BOOTX */ + +#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) */ + +#ifdef CONFIG_PPC_PASEMI + +_GLOBAL(real_205_readb) + mfmsr r7 + ori r0,r7,MSR_DR + xori r0,r0,MSR_DR + sync + mtmsrd r0 + sync + isync + LBZCIX(R3,R0,R3) + isync + mtmsrd r7 + sync + isync + blr + +_GLOBAL(real_205_writeb) + mfmsr r7 + ori r0,r7,MSR_DR + xori r0,r0,MSR_DR + sync + mtmsrd r0 + sync + isync + STBCIX(R3,R0,R4) + isync + mtmsrd r7 + sync + isync + blr + +#endif /* CONFIG_PPC_PASEMI */ + + +#if defined(CONFIG_CPU_FREQ_PMAC64) || defined(CONFIG_CPU_FREQ_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 +#endif /* CONFIG_CPU_FREQ_PMAC64 || CONFIG_CPU_FREQ_MAPLE */ + +/* 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, even those that did not find a matching + * paca in the secondary startup code. + * + * Physical (hardware) cpu id should be in r3. + */ +_GLOBAL(kexec_wait) + bcl 20,31,$+4 +1: mflr r5 + addi r5,r5,kexec_flag-1b + +99: HMT_LOW +#ifdef CONFIG_KEXEC_CORE /* use no memory without kexec */ + lwz r4,0(r5) + cmpwi 0,r4,0 + beq 99b +#ifdef CONFIG_PPC_BOOK3S_64 + li r10,0x60 + mfmsr r11 + clrrdi r11,r11,1 /* Clear MSR_LE */ + mtsrr0 r10 + mtsrr1 r11 + rfid +#else + /* Create TLB entry in book3e_secondary_core_init */ + li r4,0 + ba 0x60 +#endif +#endif + +/* 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_CORE +#ifdef CONFIG_PPC_BOOK3E_64 +/* + * BOOK3E has no real MMU mode, so we have to setup the initial TLB + * for a core to identity map v:0 to p:0. This current implementation + * assumes that 1G is enough for kexec. + */ +kexec_create_tlb: + /* + * Invalidate all non-IPROT TLB entries to avoid any TLB conflict. + * IPROT TLB entries should be >= PAGE_OFFSET and thus not conflict. + */ + PPC_TLBILX_ALL(0,R0) + sync + isync + + mfspr r10,SPRN_TLB1CFG + andi. r10,r10,TLBnCFG_N_ENTRY /* Extract # entries */ + subi r10,r10,1 /* Last entry: no conflict with kernel text */ + lis r9,MAS0_TLBSEL(1)@h + rlwimi r9,r10,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r9) */ + +/* Set up a temp identity mapping v:0 to p:0 and return to it. */ + mtspr SPRN_MAS0,r9 + + lis r9,(MAS1_VALID|MAS1_IPROT)@h + ori r9,r9,(MAS1_TSIZE(BOOK3E_PAGESZ_1GB))@l + mtspr SPRN_MAS1,r9 + + LOAD_REG_IMMEDIATE(r9, 0x0 | MAS2_M_IF_NEEDED) + mtspr SPRN_MAS2,r9 + + LOAD_REG_IMMEDIATE(r9, 0x0 | MAS3_SR | MAS3_SW | MAS3_SX) + mtspr SPRN_MAS3,r9 + li r9,0 + mtspr SPRN_MAS7,r9 + + tlbwe + isync + blr +#endif + +/* kexec_smp_wait(void) + * + * call with interrupts off + * note: this is a terminal routine, it does not save lr + * + * get phys id from paca + * switch to real mode + * mark the paca as no longer used + * join other cpus in kexec_wait(phys_id) + */ +_GLOBAL(kexec_smp_wait) + lhz r3,PACAHWCPUID(r13) + bl real_mode + + li r4,KEXEC_STATE_REAL_MODE + stb r4,PACAKEXECSTATE(r13) + + 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. + */ +SYM_FUNC_START_LOCAL(real_mode) /* assume normal blr return */ +#ifdef CONFIG_PPC_BOOK3E_64 + /* Create an identity mapping. */ + b kexec_create_tlb +#else +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 +#endif +SYM_FUNC_END(real_mode) + +/* + * kexec_sequence(newstack, start, image, control, clear_all(), + copy_with_mmu_off) + * + * 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-STACK_FRAME_MIN_SIZE(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,-STACK_FRAME_MIN_SIZE-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 /* copy_with_mmu_off */ + lhz r25,PACAHWCPUID(r13) /* get our phys cpu from paca */ + + /* disable interrupts, we are overwriting kernel data next */ +#ifdef CONFIG_PPC_BOOK3E_64 + wrteei 0 +#else + mfmsr r3 + rlwinm r3,r3,0,17,15 + mtmsrd r3,1 +#endif + + /* We need to turn the MMU off unless we are in hash mode + * under a hypervisor + */ + cmpdi r26,0 + beq 1f + bl real_mode +1: + /* copy dest pages, flush whole dest image */ + mr r3,r29 + bl CFUNC(kexec_copy_flush) /* (image) */ + + /* turn off mmu now if not done earlier */ + cmpdi r26,0 + bne 1f + bl real_mode + + /* copy 0x100 bytes starting at start to 0 */ +1: li r3,0 + mr r4,r30 /* start, aka phys mem offset */ + 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) + + cmpdi r27,0 + beq 1f + + /* clear out hardware hash page table and tlb */ +#ifdef CONFIG_PPC64_ELF_ABI_V1 + ld r12,0(r27) /* deref function descriptor */ +#else + mr r12,r27 +#endif + mtctr r12 + bctrl /* mmu_hash_ops.hpte_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)... + */ +1: 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_CORE */ |