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+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * PowerPC version
+ * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ * Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP
+ * Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu>
+ * Adapted for Power Macintosh by Paul Mackerras.
+ * Low-level exception handlers and MMU support
+ * rewritten by Paul Mackerras.
+ * Copyright (C) 1996 Paul Mackerras.
+ *
+ * Adapted for 64bit PowerPC by Dave Engebretsen, Peter Bergner, and
+ * Mike Corrigan {engebret|bergner|mikejc}@us.ibm.com
+ *
+ * This file contains the entry point for the 64-bit kernel along
+ * with some early initialization code common to all 64-bit powerpc
+ * variants.
+ */
+
+#include <linux/threads.h>
+#include <linux/init.h>
+#include <asm/reg.h>
+#include <asm/page.h>
+#include <asm/mmu.h>
+#include <asm/ppc_asm.h>
+#include <asm/head-64.h>
+#include <asm/asm-offsets.h>
+#include <asm/bug.h>
+#include <asm/cputable.h>
+#include <asm/setup.h>
+#include <asm/hvcall.h>
+#include <asm/thread_info.h>
+#include <asm/firmware.h>
+#include <asm/page_64.h>
+#include <asm/irqflags.h>
+#include <asm/kvm_book3s_asm.h>
+#include <asm/ptrace.h>
+#include <asm/hw_irq.h>
+#include <asm/cputhreads.h>
+#include <asm/ppc-opcode.h>
+#include <asm/export.h>
+#include <asm/feature-fixups.h>
+#ifdef CONFIG_PPC_BOOK3S
+#include <asm/exception-64s.h>
+#else
+#include <asm/exception-64e.h>
+#endif
+
+/* The physical memory is laid out such that the secondary processor
+ * spin code sits at 0x0000...0x00ff. On server, the vectors follow
+ * using the layout described in exceptions-64s.S
+ */
+
+/*
+ * Entering into this code we make the following assumptions:
+ *
+ * For pSeries or server processors:
+ * 1. The MMU is off & open firmware is running in real mode.
+ * 2. The primary CPU enters at __start.
+ * 3. If the RTAS supports "query-cpu-stopped-state", then secondary
+ * CPUs will enter as directed by "start-cpu" RTAS call, which is
+ * generic_secondary_smp_init, with PIR in r3.
+ * 4. Else the secondary CPUs will enter at secondary_hold (0x60) as
+ * directed by the "start-cpu" RTS call, with PIR in r3.
+ * -or- For OPAL entry:
+ * 1. The MMU is off, processor in HV mode.
+ * 2. The primary CPU enters at 0 with device-tree in r3, OPAL base
+ * in r8, and entry in r9 for debugging purposes.
+ * 3. Secondary CPUs enter as directed by OPAL_START_CPU call, which
+ * is at generic_secondary_smp_init, with PIR in r3.
+ *
+ * For Book3E processors:
+ * 1. The MMU is on running in AS0 in a state defined in ePAPR
+ * 2. The kernel is entered at __start
+ */
+
+OPEN_FIXED_SECTION(first_256B, 0x0, 0x100)
+USE_FIXED_SECTION(first_256B)
+ /*
+ * Offsets are relative from the start of fixed section, and
+ * first_256B starts at 0. Offsets are a bit easier to use here
+ * than the fixed section entry macros.
+ */
+ . = 0x0
+_GLOBAL(__start)
+ /* NOP this out unconditionally */
+BEGIN_FTR_SECTION
+ FIXUP_ENDIAN
+ b __start_initialization_multiplatform
+END_FTR_SECTION(0, 1)
+
+ /* Catch branch to 0 in real mode */
+ trap
+
+ /* Secondary processors spin on this value until it becomes non-zero.
+ * When non-zero, it contains the real address of the function the cpu
+ * should jump to.
+ */
+ .balign 8
+ .globl __secondary_hold_spinloop
+__secondary_hold_spinloop:
+ .8byte 0x0
+
+ /* Secondary processors write this value with their cpu # */
+ /* after they enter the spin loop immediately below. */
+ .globl __secondary_hold_acknowledge
+__secondary_hold_acknowledge:
+ .8byte 0x0
+
+#ifdef CONFIG_RELOCATABLE
+ /* This flag is set to 1 by a loader if the kernel should run
+ * at the loaded address instead of the linked address. This
+ * is used by kexec-tools to keep the kdump kernel in the
+ * crash_kernel region. The loader is responsible for
+ * observing the alignment requirement.
+ */
+
+#ifdef CONFIG_RELOCATABLE_TEST
+#define RUN_AT_LOAD_DEFAULT 1 /* Test relocation, do not copy to 0 */
+#else
+#define RUN_AT_LOAD_DEFAULT 0x72756e30 /* "run0" -- relocate to 0 by default */
+#endif
+
+ /* Do not move this variable as kexec-tools knows about it. */
+ . = 0x5c
+ .globl __run_at_load
+__run_at_load:
+DEFINE_FIXED_SYMBOL(__run_at_load, first_256B)
+ .long RUN_AT_LOAD_DEFAULT
+#endif
+
+ . = 0x60
+/*
+ * The following code is used to hold secondary processors
+ * in a spin loop after they have entered the kernel, but
+ * before the bulk of the kernel has been relocated. This code
+ * is relocated to physical address 0x60 before prom_init is run.
+ * All of it must fit below the first exception vector at 0x100.
+ * Use .globl here not _GLOBAL because we want __secondary_hold
+ * to be the actual text address, not a descriptor.
+ */
+ .globl __secondary_hold
+__secondary_hold:
+ FIXUP_ENDIAN
+#ifndef CONFIG_PPC_BOOK3E_64
+ mfmsr r24
+ ori r24,r24,MSR_RI
+ mtmsrd r24 /* RI on */
+#endif
+ /* Grab our physical cpu number */
+ mr r24,r3
+ /* stash r4 for book3e */
+ mr r25,r4
+
+ /* Tell the master cpu we're here */
+ /* Relocation is off & we are located at an address less */
+ /* than 0x100, so only need to grab low order offset. */
+ std r24,(ABS_ADDR(__secondary_hold_acknowledge, first_256B))(0)
+ sync
+
+ li r26,0
+#ifdef CONFIG_PPC_BOOK3E_64
+ tovirt(r26,r26)
+#endif
+ /* All secondary cpus wait here until told to start. */
+100: ld r12,(ABS_ADDR(__secondary_hold_spinloop, first_256B))(r26)
+ cmpdi 0,r12,0
+ beq 100b
+
+#if defined(CONFIG_SMP) || defined(CONFIG_KEXEC_CORE)
+#ifdef CONFIG_PPC_BOOK3E_64
+ tovirt(r12,r12)
+#endif
+ mtctr r12
+ mr r3,r24
+ /*
+ * it may be the case that other platforms have r4 right to
+ * begin with, this gives us some safety in case it is not
+ */
+#ifdef CONFIG_PPC_BOOK3E_64
+ mr r4,r25
+#else
+ li r4,0
+#endif
+ /* Make sure that patched code is visible */
+ isync
+ bctr
+#else
+0: trap
+ EMIT_BUG_ENTRY 0b, __FILE__, __LINE__, 0
+#endif
+CLOSE_FIXED_SECTION(first_256B)
+
+/*
+ * On server, we include the exception vectors code here as it
+ * relies on absolute addressing which is only possible within
+ * this compilation unit
+ */
+#ifdef CONFIG_PPC_BOOK3S
+#include "exceptions-64s.S"
+#else
+OPEN_TEXT_SECTION(0x100)
+#endif
+
+USE_TEXT_SECTION()
+
+#include "interrupt_64.S"
+
+#ifdef CONFIG_PPC_BOOK3E_64
+/*
+ * The booting_thread_hwid holds the thread id we want to boot in cpu
+ * hotplug case. It is set by cpu hotplug code, and is invalid by default.
+ * The thread id is the same as the initial value of SPRN_PIR[THREAD_ID]
+ * bit field.
+ */
+ .globl booting_thread_hwid
+booting_thread_hwid:
+ .long INVALID_THREAD_HWID
+ .align 3
+/*
+ * start a thread in the same core
+ * input parameters:
+ * r3 = the thread physical id
+ * r4 = the entry point where thread starts
+ */
+_GLOBAL(book3e_start_thread)
+ LOAD_REG_IMMEDIATE(r5, MSR_KERNEL)
+ cmpwi r3, 0
+ beq 10f
+ cmpwi r3, 1
+ beq 11f
+ /* If the thread id is invalid, just exit. */
+ b 13f
+10:
+ MTTMR(TMRN_IMSR0, 5)
+ MTTMR(TMRN_INIA0, 4)
+ b 12f
+11:
+ MTTMR(TMRN_IMSR1, 5)
+ MTTMR(TMRN_INIA1, 4)
+12:
+ isync
+ li r6, 1
+ sld r6, r6, r3
+ mtspr SPRN_TENS, r6
+13:
+ blr
+
+/*
+ * stop a thread in the same core
+ * input parameter:
+ * r3 = the thread physical id
+ */
+_GLOBAL(book3e_stop_thread)
+ cmpwi r3, 0
+ beq 10f
+ cmpwi r3, 1
+ beq 10f
+ /* If the thread id is invalid, just exit. */
+ b 13f
+10:
+ li r4, 1
+ sld r4, r4, r3
+ mtspr SPRN_TENC, r4
+13:
+ blr
+
+_GLOBAL(fsl_secondary_thread_init)
+ mfspr r4,SPRN_BUCSR
+
+ /* Enable branch prediction */
+ lis r3,BUCSR_INIT@h
+ ori r3,r3,BUCSR_INIT@l
+ mtspr SPRN_BUCSR,r3
+ isync
+
+ /*
+ * Fix PIR to match the linear numbering in the device tree.
+ *
+ * On e6500, the reset value of PIR uses the low three bits for
+ * the thread within a core, and the upper bits for the core
+ * number. There are two threads per core, so shift everything
+ * but the low bit right by two bits so that the cpu numbering is
+ * continuous.
+ *
+ * If the old value of BUCSR is non-zero, this thread has run
+ * before. Thus, we assume we are coming from kexec or a similar
+ * scenario, and PIR is already set to the correct value. This
+ * is a bit of a hack, but there are limited opportunities for
+ * getting information into the thread and the alternatives
+ * seemed like they'd be overkill. We can't tell just by looking
+ * at the old PIR value which state it's in, since the same value
+ * could be valid for one thread out of reset and for a different
+ * thread in Linux.
+ */
+
+ mfspr r3, SPRN_PIR
+ cmpwi r4,0
+ bne 1f
+ rlwimi r3, r3, 30, 2, 30
+ mtspr SPRN_PIR, r3
+1:
+ mr r24,r3
+
+ /* turn on 64-bit mode */
+ bl enable_64b_mode
+
+ /* get a valid TOC pointer, wherever we're mapped at */
+ bl relative_toc
+ tovirt(r2,r2)
+
+ /* Book3E initialization */
+ mr r3,r24
+ bl book3e_secondary_thread_init
+ b generic_secondary_common_init
+
+#endif /* CONFIG_PPC_BOOK3E_64 */
+
+/*
+ * On pSeries and most other platforms, secondary processors spin
+ * in the following code.
+ * At entry, r3 = this processor's number (physical cpu id)
+ *
+ * On Book3E, r4 = 1 to indicate that the initial TLB entry for
+ * this core already exists (setup via some other mechanism such
+ * as SCOM before entry).
+ */
+_GLOBAL(generic_secondary_smp_init)
+ FIXUP_ENDIAN
+ mr r24,r3
+ mr r25,r4
+
+ /* turn on 64-bit mode */
+ bl enable_64b_mode
+
+ /* get a valid TOC pointer, wherever we're mapped at */
+ bl relative_toc
+ tovirt(r2,r2)
+
+#ifdef CONFIG_PPC_BOOK3E_64
+ /* Book3E initialization */
+ mr r3,r24
+ mr r4,r25
+ bl book3e_secondary_core_init
+
+/*
+ * After common core init has finished, check if the current thread is the
+ * one we wanted to boot. If not, start the specified thread and stop the
+ * current thread.
+ */
+ LOAD_REG_ADDR(r4, booting_thread_hwid)
+ lwz r3, 0(r4)
+ li r5, INVALID_THREAD_HWID
+ cmpw r3, r5
+ beq 20f
+
+ /*
+ * The value of booting_thread_hwid has been stored in r3,
+ * so make it invalid.
+ */
+ stw r5, 0(r4)
+
+ /*
+ * Get the current thread id and check if it is the one we wanted.
+ * If not, start the one specified in booting_thread_hwid and stop
+ * the current thread.
+ */
+ mfspr r8, SPRN_TIR
+ cmpw r3, r8
+ beq 20f
+
+ /* start the specified thread */
+ LOAD_REG_ADDR(r5, fsl_secondary_thread_init)
+ ld r4, 0(r5)
+ bl book3e_start_thread
+
+ /* stop the current thread */
+ mr r3, r8
+ bl book3e_stop_thread
+10:
+ b 10b
+20:
+#endif
+
+generic_secondary_common_init:
+ /* Set up a paca value for this processor. Since we have the
+ * physical cpu id in r24, we need to search the pacas to find
+ * which logical id maps to our physical one.
+ */
+#ifndef CONFIG_SMP
+ b kexec_wait /* wait for next kernel if !SMP */
+#else
+ LOAD_REG_ADDR(r8, paca_ptrs) /* Load paca_ptrs pointe */
+ ld r8,0(r8) /* Get base vaddr of array */
+#if (NR_CPUS == 1) || defined(CONFIG_FORCE_NR_CPUS)
+ LOAD_REG_IMMEDIATE(r7, NR_CPUS)
+#else
+ LOAD_REG_ADDR(r7, nr_cpu_ids) /* Load nr_cpu_ids address */
+ lwz r7,0(r7) /* also the max paca allocated */
+#endif
+ li r5,0 /* logical cpu id */
+1:
+ sldi r9,r5,3 /* get paca_ptrs[] index from cpu id */
+ ldx r13,r9,r8 /* r13 = paca_ptrs[cpu id] */
+ lhz r6,PACAHWCPUID(r13) /* Load HW procid from paca */
+ cmpw r6,r24 /* Compare to our id */
+ beq 2f
+ addi r5,r5,1
+ cmpw r5,r7 /* Check if more pacas exist */
+ blt 1b
+
+ mr r3,r24 /* not found, copy phys to r3 */
+ b kexec_wait /* next kernel might do better */
+
+2: SET_PACA(r13)
+#ifdef CONFIG_PPC_BOOK3E_64
+ addi r12,r13,PACA_EXTLB /* and TLB exc frame in another */
+ mtspr SPRN_SPRG_TLB_EXFRAME,r12
+#endif
+
+ /* From now on, r24 is expected to be logical cpuid */
+ mr r24,r5
+
+ /* Create a temp kernel stack for use before relocation is on. */
+ ld r1,PACAEMERGSP(r13)
+ subi r1,r1,STACK_FRAME_OVERHEAD
+
+ /* See if we need to call a cpu state restore handler */
+ LOAD_REG_ADDR(r23, cur_cpu_spec)
+ ld r23,0(r23)
+ ld r12,CPU_SPEC_RESTORE(r23)
+ cmpdi 0,r12,0
+ beq 3f
+#ifdef CONFIG_PPC64_ELF_ABI_V1
+ ld r12,0(r12)
+#endif
+ mtctr r12
+ bctrl
+
+3: LOAD_REG_ADDR(r3, spinning_secondaries) /* Decrement spinning_secondaries */
+ lwarx r4,0,r3
+ subi r4,r4,1
+ stwcx. r4,0,r3
+ bne 3b
+ isync
+
+4: HMT_LOW
+ lbz r23,PACAPROCSTART(r13) /* Test if this processor should */
+ /* start. */
+ cmpwi 0,r23,0
+ beq 4b /* Loop until told to go */
+
+ sync /* order paca.run and cur_cpu_spec */
+ isync /* In case code patching happened */
+
+ b __secondary_start
+#endif /* SMP */
+
+/*
+ * Turn the MMU off.
+ * Assumes we're mapped EA == RA if the MMU is on.
+ */
+#ifdef CONFIG_PPC_BOOK3S
+__mmu_off:
+ mfmsr r3
+ andi. r0,r3,MSR_IR|MSR_DR
+ beqlr
+ mflr r4
+ andc r3,r3,r0
+ mtspr SPRN_SRR0,r4
+ mtspr SPRN_SRR1,r3
+ sync
+ rfid
+ b . /* prevent speculative execution */
+#endif
+
+
+/*
+ * Here is our main kernel entry point. We support currently 2 kind of entries
+ * depending on the value of r5.
+ *
+ * r5 != NULL -> OF entry, we go to prom_init, "legacy" parameter content
+ * in r3...r7
+ *
+ * r5 == NULL -> kexec style entry. r3 is a physical pointer to the
+ * DT block, r4 is a physical pointer to the kernel itself
+ *
+ */
+__start_initialization_multiplatform:
+ /* Make sure we are running in 64 bits mode */
+ bl enable_64b_mode
+
+ /* Zero r13 (paca) so early program check / mce don't use it */
+ li r13,0
+
+ /* Get TOC pointer (current runtime address) */
+ bl relative_toc
+
+ /* find out where we are now */
+ bcl 20,31,$+4
+0: mflr r26 /* r26 = runtime addr here */
+ addis r26,r26,(_stext - 0b)@ha
+ addi r26,r26,(_stext - 0b)@l /* current runtime base addr */
+
+ /*
+ * Are we booted from a PROM Of-type client-interface ?
+ */
+ cmpldi cr0,r5,0
+ beq 1f
+ b __boot_from_prom /* yes -> prom */
+1:
+ /* Save parameters */
+ mr r31,r3
+ mr r30,r4
+#ifdef CONFIG_PPC_EARLY_DEBUG_OPAL
+ /* Save OPAL entry */
+ mr r28,r8
+ mr r29,r9
+#endif
+
+#ifdef CONFIG_PPC_BOOK3E_64
+ bl start_initialization_book3e
+ b __after_prom_start
+#else
+ /* Setup some critical 970 SPRs before switching MMU off */
+ mfspr r0,SPRN_PVR
+ srwi r0,r0,16
+ cmpwi r0,0x39 /* 970 */
+ beq 1f
+ cmpwi r0,0x3c /* 970FX */
+ beq 1f
+ cmpwi r0,0x44 /* 970MP */
+ beq 1f
+ cmpwi r0,0x45 /* 970GX */
+ bne 2f
+1: bl __cpu_preinit_ppc970
+2:
+
+ /* Switch off MMU if not already off */
+ bl __mmu_off
+ b __after_prom_start
+#endif /* CONFIG_PPC_BOOK3E_64 */
+
+__REF
+__boot_from_prom:
+#ifdef CONFIG_PPC_OF_BOOT_TRAMPOLINE
+ /* Save parameters */
+ mr r31,r3
+ mr r30,r4
+ mr r29,r5
+ mr r28,r6
+ mr r27,r7
+
+ /*
+ * Align the stack to 16-byte boundary
+ * Depending on the size and layout of the ELF sections in the initial
+ * boot binary, the stack pointer may be unaligned on PowerMac
+ */
+ rldicr r1,r1,0,59
+
+#ifdef CONFIG_RELOCATABLE
+ /* Relocate code for where we are now */
+ mr r3,r26
+ bl relocate
+#endif
+
+ /* Restore parameters */
+ mr r3,r31
+ mr r4,r30
+ mr r5,r29
+ mr r6,r28
+ mr r7,r27
+
+ /* Do all of the interaction with OF client interface */
+ mr r8,r26
+ bl prom_init
+#endif /* #CONFIG_PPC_OF_BOOT_TRAMPOLINE */
+
+ /* We never return. We also hit that trap if trying to boot
+ * from OF while CONFIG_PPC_OF_BOOT_TRAMPOLINE isn't selected */
+ trap
+ .previous
+
+__after_prom_start:
+#ifdef CONFIG_RELOCATABLE
+ /* process relocations for the final address of the kernel */
+ lis r25,PAGE_OFFSET@highest /* compute virtual base of kernel */
+ sldi r25,r25,32
+#if defined(CONFIG_PPC_BOOK3E_64)
+ tovirt(r26,r26) /* on booke, we already run at PAGE_OFFSET */
+#endif
+ lwz r7,(FIXED_SYMBOL_ABS_ADDR(__run_at_load))(r26)
+#if defined(CONFIG_PPC_BOOK3E_64)
+ tophys(r26,r26)
+#endif
+ cmplwi cr0,r7,1 /* flagged to stay where we are ? */
+ bne 1f
+ add r25,r25,r26
+1: mr r3,r25
+ bl relocate
+#if defined(CONFIG_PPC_BOOK3E_64)
+ /* IVPR needs to be set after relocation. */
+ bl init_core_book3e
+#endif
+#endif
+
+/*
+ * We need to run with _stext at physical address PHYSICAL_START.
+ * This will leave some code in the first 256B of
+ * real memory, which are reserved for software use.
+ *
+ * Note: This process overwrites the OF exception vectors.
+ */
+ li r3,0 /* target addr */
+#ifdef CONFIG_PPC_BOOK3E_64
+ tovirt(r3,r3) /* on booke, we already run at PAGE_OFFSET */
+#endif
+ mr. r4,r26 /* In some cases the loader may */
+#if defined(CONFIG_PPC_BOOK3E_64)
+ tovirt(r4,r4)
+#endif
+ beq 9f /* have already put us at zero */
+ li r6,0x100 /* Start offset, the first 0x100 */
+ /* bytes were copied earlier. */
+
+#ifdef CONFIG_RELOCATABLE
+/*
+ * Check if the kernel has to be running as relocatable kernel based on the
+ * variable __run_at_load, if it is set the kernel is treated as relocatable
+ * kernel, otherwise it will be moved to PHYSICAL_START
+ */
+#if defined(CONFIG_PPC_BOOK3E_64)
+ tovirt(r26,r26) /* on booke, we already run at PAGE_OFFSET */
+#endif
+ lwz r7,(FIXED_SYMBOL_ABS_ADDR(__run_at_load))(r26)
+ cmplwi cr0,r7,1
+ bne 3f
+
+#ifdef CONFIG_PPC_BOOK3E_64
+ LOAD_REG_ADDR(r5, __end_interrupts)
+ LOAD_REG_ADDR(r11, _stext)
+ sub r5,r5,r11
+#else
+ /* just copy interrupts */
+ LOAD_REG_IMMEDIATE_SYM(r5, r11, FIXED_SYMBOL_ABS_ADDR(__end_interrupts))
+#endif
+ b 5f
+3:
+#endif
+ /* # bytes of memory to copy */
+ lis r5,(ABS_ADDR(copy_to_here, text))@ha
+ addi r5,r5,(ABS_ADDR(copy_to_here, text))@l
+
+ bl copy_and_flush /* copy the first n bytes */
+ /* this includes the code being */
+ /* executed here. */
+ /* Jump to the copy of this code that we just made */
+ addis r8,r3,(ABS_ADDR(4f, text))@ha
+ addi r12,r8,(ABS_ADDR(4f, text))@l
+ mtctr r12
+ bctr
+
+.balign 8
+p_end: .8byte _end - copy_to_here
+
+4:
+ /*
+ * Now copy the rest of the kernel up to _end, add
+ * _end - copy_to_here to the copy limit and run again.
+ */
+ addis r8,r26,(ABS_ADDR(p_end, text))@ha
+ ld r8,(ABS_ADDR(p_end, text))@l(r8)
+ add r5,r5,r8
+5: bl copy_and_flush /* copy the rest */
+
+9: b start_here_multiplatform
+
+/*
+ * Copy routine used to copy the kernel to start at physical address 0
+ * and flush and invalidate the caches as needed.
+ * r3 = dest addr, r4 = source addr, r5 = copy limit, r6 = start offset
+ * on exit, r3, r4, r5 are unchanged, r6 is updated to be >= r5.
+ *
+ * Note: this routine *only* clobbers r0, r6 and lr
+ */
+_GLOBAL(copy_and_flush)
+ addi r5,r5,-8
+ addi r6,r6,-8
+4: li r0,8 /* Use the smallest common */
+ /* denominator cache line */
+ /* size. This results in */
+ /* extra cache line flushes */
+ /* but operation is correct. */
+ /* Can't get cache line size */
+ /* from NACA as it is being */
+ /* moved too. */
+
+ mtctr r0 /* put # words/line in ctr */
+3: addi r6,r6,8 /* copy a cache line */
+ ldx r0,r6,r4
+ stdx r0,r6,r3
+ bdnz 3b
+ dcbst r6,r3 /* write it to memory */
+ sync
+ icbi r6,r3 /* flush the icache line */
+ cmpld 0,r6,r5
+ blt 4b
+ sync
+ addi r5,r5,8
+ addi r6,r6,8
+ isync
+ blr
+
+_ASM_NOKPROBE_SYMBOL(copy_and_flush); /* Called in real mode */
+
+.align 8
+copy_to_here:
+
+#ifdef CONFIG_SMP
+#ifdef CONFIG_PPC_PMAC
+/*
+ * On PowerMac, secondary processors starts from the reset vector, which
+ * is temporarily turned into a call to one of the functions below.
+ */
+ .section ".text";
+ .align 2 ;
+
+ .globl __secondary_start_pmac_0
+__secondary_start_pmac_0:
+ /* NB the entries for cpus 0, 1, 2 must each occupy 8 bytes. */
+ li r24,0
+ b 1f
+ li r24,1
+ b 1f
+ li r24,2
+ b 1f
+ li r24,3
+1:
+
+_GLOBAL(pmac_secondary_start)
+ /* turn on 64-bit mode */
+ bl enable_64b_mode
+
+ li r0,0
+ mfspr r3,SPRN_HID4
+ rldimi r3,r0,40,23 /* clear bit 23 (rm_ci) */
+ sync
+ mtspr SPRN_HID4,r3
+ isync
+ sync
+ slbia
+
+ /* get TOC pointer (real address) */
+ bl relative_toc
+ tovirt(r2,r2)
+
+ /* Copy some CPU settings from CPU 0 */
+ bl __restore_cpu_ppc970
+
+ /* pSeries do that early though I don't think we really need it */
+ mfmsr r3
+ ori r3,r3,MSR_RI
+ mtmsrd r3 /* RI on */
+
+ /* Set up a paca value for this processor. */
+ LOAD_REG_ADDR(r4,paca_ptrs) /* Load paca pointer */
+ ld r4,0(r4) /* Get base vaddr of paca_ptrs array */
+ sldi r5,r24,3 /* get paca_ptrs[] index from cpu id */
+ ldx r13,r5,r4 /* r13 = paca_ptrs[cpu id] */
+ SET_PACA(r13) /* Save vaddr of paca in an SPRG*/
+
+ /* Mark interrupts soft and hard disabled (they might be enabled
+ * in the PACA when doing hotplug)
+ */
+ li r0,IRQS_DISABLED
+ stb r0,PACAIRQSOFTMASK(r13)
+ li r0,PACA_IRQ_HARD_DIS
+ stb r0,PACAIRQHAPPENED(r13)
+
+ /* Create a temp kernel stack for use before relocation is on. */
+ ld r1,PACAEMERGSP(r13)
+ subi r1,r1,STACK_FRAME_OVERHEAD
+
+ b __secondary_start
+
+#endif /* CONFIG_PPC_PMAC */
+
+/*
+ * This function is called after the master CPU has released the
+ * secondary processors. The execution environment is relocation off.
+ * The paca for this processor has the following fields initialized at
+ * this point:
+ * 1. Processor number
+ * 2. Segment table pointer (virtual address)
+ * On entry the following are set:
+ * r1 = stack pointer (real addr of temp stack)
+ * r24 = cpu# (in Linux terms)
+ * r13 = paca virtual address
+ * SPRG_PACA = paca virtual address
+ */
+ .section ".text";
+ .align 2 ;
+
+ .globl __secondary_start
+__secondary_start:
+ /* Set thread priority to MEDIUM */
+ HMT_MEDIUM
+
+ /*
+ * Do early setup for this CPU, in particular initialising the MMU so we
+ * can turn it on below. This is a call to C, which is OK, we're still
+ * running on the emergency stack.
+ */
+ bl early_setup_secondary
+
+ /*
+ * The primary has initialized our kernel stack for us in the paca, grab
+ * it and put it in r1. We must *not* use it until we turn on the MMU
+ * below, because it may not be inside the RMO.
+ */
+ ld r1, PACAKSAVE(r13)
+
+ /* Clear backchain so we get nice backtraces */
+ li r7,0
+ mtlr r7
+
+ /* Mark interrupts soft and hard disabled (they might be enabled
+ * in the PACA when doing hotplug)
+ */
+ li r7,IRQS_DISABLED
+ stb r7,PACAIRQSOFTMASK(r13)
+ li r0,PACA_IRQ_HARD_DIS
+ stb r0,PACAIRQHAPPENED(r13)
+
+ /* enable MMU and jump to start_secondary */
+ LOAD_REG_ADDR(r3, start_secondary_prolog)
+ LOAD_REG_IMMEDIATE(r4, MSR_KERNEL)
+
+ mtspr SPRN_SRR0,r3
+ mtspr SPRN_SRR1,r4
+ RFI_TO_KERNEL
+ b . /* prevent speculative execution */
+
+/*
+ * Running with relocation on at this point. All we want to do is
+ * zero the stack back-chain pointer and get the TOC virtual address
+ * before going into C code.
+ */
+start_secondary_prolog:
+ LOAD_PACA_TOC()
+ li r3,0
+ std r3,0(r1) /* Zero the stack frame pointer */
+ bl start_secondary
+ b .
+/*
+ * Reset stack pointer and call start_secondary
+ * to continue with online operation when woken up
+ * from cede in cpu offline.
+ */
+_GLOBAL(start_secondary_resume)
+ ld r1,PACAKSAVE(r13) /* Reload kernel stack pointer */
+ li r3,0
+ std r3,0(r1) /* Zero the stack frame pointer */
+ bl start_secondary
+ b .
+#endif
+
+/*
+ * This subroutine clobbers r11 and r12
+ */
+enable_64b_mode:
+ mfmsr r11 /* grab the current MSR */
+#ifdef CONFIG_PPC_BOOK3E_64
+ oris r11,r11,0x8000 /* CM bit set, we'll set ICM later */
+ mtmsr r11
+#else /* CONFIG_PPC_BOOK3E_64 */
+ LOAD_REG_IMMEDIATE(r12, MSR_64BIT)
+ or r11,r11,r12
+ mtmsrd r11
+ isync
+#endif
+ blr
+
+/*
+ * This puts the TOC pointer into r2, offset by 0x8000 (as expected
+ * by the toolchain). It computes the correct value for wherever we
+ * are running at the moment, using position-independent code.
+ *
+ * Note: The compiler constructs pointers using offsets from the
+ * TOC in -mcmodel=medium mode. After we relocate to 0 but before
+ * the MMU is on we need our TOC to be a virtual address otherwise
+ * these pointers will be real addresses which may get stored and
+ * accessed later with the MMU on. We use tovirt() at the call
+ * sites to handle this.
+ */
+_GLOBAL(relative_toc)
+ mflr r0
+ bcl 20,31,$+4
+0: mflr r11
+ ld r2,(p_toc - 0b)(r11)
+ add r2,r2,r11
+ mtlr r0
+ blr
+
+.balign 8
+p_toc: .8byte .TOC. - 0b
+
+/*
+ * This is where the main kernel code starts.
+ */
+__REF
+start_here_multiplatform:
+ /* set up the TOC */
+ bl relative_toc
+ tovirt(r2,r2)
+
+ /* Clear out the BSS. It may have been done in prom_init,
+ * already but that's irrelevant since prom_init will soon
+ * be detached from the kernel completely. Besides, we need
+ * to clear it now for kexec-style entry.
+ */
+ LOAD_REG_ADDR(r11,__bss_stop)
+ LOAD_REG_ADDR(r8,__bss_start)
+ sub r11,r11,r8 /* bss size */
+ addi r11,r11,7 /* round up to an even double word */
+ srdi. r11,r11,3 /* shift right by 3 */
+ beq 4f
+ addi r8,r8,-8
+ li r0,0
+ mtctr r11 /* zero this many doublewords */
+3: stdu r0,8(r8)
+ bdnz 3b
+4:
+
+#ifdef CONFIG_PPC_EARLY_DEBUG_OPAL
+ /* Setup OPAL entry */
+ LOAD_REG_ADDR(r11, opal)
+ std r28,0(r11);
+ std r29,8(r11);
+#endif
+
+#ifndef CONFIG_PPC_BOOK3E_64
+ mfmsr r6
+ ori r6,r6,MSR_RI
+ mtmsrd r6 /* RI on */
+#endif
+
+#ifdef CONFIG_RELOCATABLE
+ /* Save the physical address we're running at in kernstart_addr */
+ LOAD_REG_ADDR(r4, kernstart_addr)
+ clrldi r0,r25,2
+ std r0,0(r4)
+#endif
+
+ /* set up a stack pointer */
+ LOAD_REG_ADDR(r3,init_thread_union)
+ LOAD_REG_IMMEDIATE(r1,THREAD_SIZE)
+ add r1,r3,r1
+ li r0,0
+ stdu r0,-STACK_FRAME_OVERHEAD(r1)
+
+ /*
+ * Do very early kernel initializations, including initial hash table
+ * and SLB setup before we turn on relocation.
+ */
+
+#ifdef CONFIG_KASAN
+ bl kasan_early_init
+#endif
+ /* Restore parameters passed from prom_init/kexec */
+ mr r3,r31
+ LOAD_REG_ADDR(r12, DOTSYM(early_setup))
+ mtctr r12
+ bctrl /* also sets r13 and SPRG_PACA */
+
+ LOAD_REG_ADDR(r3, start_here_common)
+ ld r4,PACAKMSR(r13)
+ mtspr SPRN_SRR0,r3
+ mtspr SPRN_SRR1,r4
+ RFI_TO_KERNEL
+ b . /* prevent speculative execution */
+
+ /* This is where all platforms converge execution */
+
+start_here_common:
+ /* relocation is on at this point */
+ std r1,PACAKSAVE(r13)
+
+ /* Load the TOC (virtual address) */
+ LOAD_PACA_TOC()
+
+ /* Mark interrupts soft and hard disabled (they might be enabled
+ * in the PACA when doing hotplug)
+ */
+ li r0,IRQS_DISABLED
+ stb r0,PACAIRQSOFTMASK(r13)
+ li r0,PACA_IRQ_HARD_DIS
+ stb r0,PACAIRQHAPPENED(r13)
+
+ /* Generic kernel entry */
+ bl start_kernel
+
+ /* Not reached */
+0: trap
+ EMIT_BUG_ENTRY 0b, __FILE__, __LINE__, 0
+ .previous