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+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Kernel execution entry point code.
+ *
+ * Copyright (c) 1995-1996 Gary Thomas <gdt@linuxppc.org>
+ * Initial PowerPC version.
+ * Copyright (c) 1996 Cort Dougan <cort@cs.nmt.edu>
+ * Rewritten for PReP
+ * Copyright (c) 1996 Paul Mackerras <paulus@cs.anu.edu.au>
+ * Low-level exception handers, MMU support, and rewrite.
+ * Copyright (c) 1997 Dan Malek <dmalek@jlc.net>
+ * PowerPC 8xx modifications.
+ * Copyright (c) 1998-1999 TiVo, Inc.
+ * PowerPC 403GCX modifications.
+ * Copyright (c) 1999 Grant Erickson <grant@lcse.umn.edu>
+ * PowerPC 403GCX/405GP modifications.
+ * Copyright 2000 MontaVista Software Inc.
+ * PPC405 modifications
+ * PowerPC 403GCX/405GP modifications.
+ * Author: MontaVista Software, Inc.
+ * frank_rowand@mvista.com or source@mvista.com
+ * debbie_chu@mvista.com
+ * Copyright 2002-2004 MontaVista Software, Inc.
+ * PowerPC 44x support, Matt Porter <mporter@kernel.crashing.org>
+ * Copyright 2004 Freescale Semiconductor, Inc
+ * PowerPC e500 modifications, Kumar Gala <galak@kernel.crashing.org>
+ */
+
+#include <linux/init.h>
+#include <linux/threads.h>
+#include <linux/pgtable.h>
+#include <asm/processor.h>
+#include <asm/page.h>
+#include <asm/mmu.h>
+#include <asm/cputable.h>
+#include <asm/thread_info.h>
+#include <asm/ppc_asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/cache.h>
+#include <asm/ptrace.h>
+#include <asm/export.h>
+#include <asm/feature-fixups.h>
+#include "head_booke.h"
+
+/* As with the other PowerPC ports, it is expected that when code
+ * execution begins here, the following registers contain valid, yet
+ * optional, information:
+ *
+ * r3 - Board info structure pointer (DRAM, frequency, MAC address, etc.)
+ * r4 - Starting address of the init RAM disk
+ * r5 - Ending address of the init RAM disk
+ * r6 - Start of kernel command line string (e.g. "mem=128")
+ * r7 - End of kernel command line string
+ *
+ */
+ __HEAD
+_GLOBAL(_stext);
+_GLOBAL(_start);
+ /*
+ * Reserve a word at a fixed location to store the address
+ * of abatron_pteptrs
+ */
+ nop
+
+ /* Translate device tree address to physical, save in r30/r31 */
+ bl get_phys_addr
+ mr r30,r3
+ mr r31,r4
+
+ li r25,0 /* phys kernel start (low) */
+ li r24,0 /* CPU number */
+ li r23,0 /* phys kernel start (high) */
+
+#ifdef CONFIG_RELOCATABLE
+ LOAD_REG_ADDR_PIC(r3, _stext) /* Get our current runtime base */
+
+ /* Translate _stext address to physical, save in r23/r25 */
+ bl get_phys_addr
+ mr r23,r3
+ mr r25,r4
+
+ bcl 20,31,$+4
+0: mflr r8
+ addis r3,r8,(is_second_reloc - 0b)@ha
+ lwz r19,(is_second_reloc - 0b)@l(r3)
+
+ /* Check if this is the second relocation. */
+ cmpwi r19,1
+ bne 1f
+
+ /*
+ * For the second relocation, we already get the real memstart_addr
+ * from device tree. So we will map PAGE_OFFSET to memstart_addr,
+ * then the virtual address of start kernel should be:
+ * PAGE_OFFSET + (kernstart_addr - memstart_addr)
+ * Since the offset between kernstart_addr and memstart_addr should
+ * never be beyond 1G, so we can just use the lower 32bit of them
+ * for the calculation.
+ */
+ lis r3,PAGE_OFFSET@h
+
+ addis r4,r8,(kernstart_addr - 0b)@ha
+ addi r4,r4,(kernstart_addr - 0b)@l
+ lwz r5,4(r4)
+
+ addis r6,r8,(memstart_addr - 0b)@ha
+ addi r6,r6,(memstart_addr - 0b)@l
+ lwz r7,4(r6)
+
+ subf r5,r7,r5
+ add r3,r3,r5
+ b 2f
+
+1:
+ /*
+ * We have the runtime (virtual) address of our base.
+ * We calculate our shift of offset from a 64M page.
+ * We could map the 64M page we belong to at PAGE_OFFSET and
+ * get going from there.
+ */
+ lis r4,KERNELBASE@h
+ ori r4,r4,KERNELBASE@l
+ rlwinm r6,r25,0,0x3ffffff /* r6 = PHYS_START % 64M */
+ rlwinm r5,r4,0,0x3ffffff /* r5 = KERNELBASE % 64M */
+ subf r3,r5,r6 /* r3 = r6 - r5 */
+ add r3,r4,r3 /* Required Virtual Address */
+
+2: bl relocate
+
+ /*
+ * For the second relocation, we already set the right tlb entries
+ * for the kernel space, so skip the code in 85xx_entry_mapping.S
+ */
+ cmpwi r19,1
+ beq set_ivor
+#endif
+
+/* We try to not make any assumptions about how the boot loader
+ * setup or used the TLBs. We invalidate all mappings from the
+ * boot loader and load a single entry in TLB1[0] to map the
+ * first 64M of kernel memory. Any boot info passed from the
+ * bootloader needs to live in this first 64M.
+ *
+ * Requirement on bootloader:
+ * - The page we're executing in needs to reside in TLB1 and
+ * have IPROT=1. If not an invalidate broadcast could
+ * evict the entry we're currently executing in.
+ *
+ * r3 = Index of TLB1 were executing in
+ * r4 = Current MSR[IS]
+ * r5 = Index of TLB1 temp mapping
+ *
+ * Later in mapin_ram we will correctly map lowmem, and resize TLB1[0]
+ * if needed
+ */
+
+_GLOBAL(__early_start)
+ LOAD_REG_ADDR_PIC(r20, kernstart_virt_addr)
+ lwz r20,0(r20)
+
+#define ENTRY_MAPPING_BOOT_SETUP
+#include "85xx_entry_mapping.S"
+#undef ENTRY_MAPPING_BOOT_SETUP
+
+set_ivor:
+ /* Establish the interrupt vector offsets */
+ SET_IVOR(0, CriticalInput);
+ SET_IVOR(1, MachineCheck);
+ SET_IVOR(2, DataStorage);
+ SET_IVOR(3, InstructionStorage);
+ SET_IVOR(4, ExternalInput);
+ SET_IVOR(5, Alignment);
+ SET_IVOR(6, Program);
+ SET_IVOR(7, FloatingPointUnavailable);
+ SET_IVOR(8, SystemCall);
+ SET_IVOR(9, AuxillaryProcessorUnavailable);
+ SET_IVOR(10, Decrementer);
+ SET_IVOR(11, FixedIntervalTimer);
+ SET_IVOR(12, WatchdogTimer);
+ SET_IVOR(13, DataTLBError);
+ SET_IVOR(14, InstructionTLBError);
+ SET_IVOR(15, DebugCrit);
+
+ /* Establish the interrupt vector base */
+ lis r4,interrupt_base@h /* IVPR only uses the high 16-bits */
+ mtspr SPRN_IVPR,r4
+
+ /* Setup the defaults for TLB entries */
+ li r2,(MAS4_TSIZED(BOOK3E_PAGESZ_4K))@l
+ mtspr SPRN_MAS4, r2
+
+#if !defined(CONFIG_BDI_SWITCH)
+ /*
+ * The Abatron BDI JTAG debugger does not tolerate others
+ * mucking with the debug registers.
+ */
+ lis r2,DBCR0_IDM@h
+ mtspr SPRN_DBCR0,r2
+ isync
+ /* clear any residual debug events */
+ li r2,-1
+ mtspr SPRN_DBSR,r2
+#endif
+
+#ifdef CONFIG_SMP
+ /* Check to see if we're the second processor, and jump
+ * to the secondary_start code if so
+ */
+ LOAD_REG_ADDR_PIC(r24, boot_cpuid)
+ lwz r24, 0(r24)
+ cmpwi r24, -1
+ mfspr r24,SPRN_PIR
+ bne __secondary_start
+#endif
+
+ /*
+ * This is where the main kernel code starts.
+ */
+
+ /* ptr to current */
+ lis r2,init_task@h
+ ori r2,r2,init_task@l
+
+ /* ptr to current thread */
+ addi r4,r2,THREAD /* init task's THREAD */
+ mtspr SPRN_SPRG_THREAD,r4
+
+ /* stack */
+ lis r1,init_thread_union@h
+ ori r1,r1,init_thread_union@l
+ li r0,0
+ stwu r0,THREAD_SIZE-STACK_FRAME_OVERHEAD(r1)
+
+#ifdef CONFIG_SMP
+ stw r24, TASK_CPU(r2)
+#endif
+
+ bl early_init
+
+#ifdef CONFIG_KASAN
+ bl kasan_early_init
+#endif
+#ifdef CONFIG_RELOCATABLE
+ mr r3,r30
+ mr r4,r31
+#ifdef CONFIG_PHYS_64BIT
+ mr r5,r23
+ mr r6,r25
+#else
+ mr r5,r25
+#endif
+ bl relocate_init
+#endif
+
+#ifdef CONFIG_DYNAMIC_MEMSTART
+ lis r3,kernstart_addr@ha
+ la r3,kernstart_addr@l(r3)
+#ifdef CONFIG_PHYS_64BIT
+ stw r23,0(r3)
+ stw r25,4(r3)
+#else
+ stw r25,0(r3)
+#endif
+#endif
+
+/*
+ * Decide what sort of machine this is and initialize the MMU.
+ */
+ mr r3,r30
+ mr r4,r31
+ bl machine_init
+ bl MMU_init
+
+ /* Setup PTE pointers for the Abatron bdiGDB */
+ lis r6, swapper_pg_dir@h
+ ori r6, r6, swapper_pg_dir@l
+ lis r5, abatron_pteptrs@h
+ ori r5, r5, abatron_pteptrs@l
+ lis r3, kernstart_virt_addr@ha
+ lwz r4, kernstart_virt_addr@l(r3)
+ stw r5, 0(r4) /* Save abatron_pteptrs at a fixed location */
+ stw r6, 0(r5)
+
+ /* Let's move on */
+ lis r4,start_kernel@h
+ ori r4,r4,start_kernel@l
+ lis r3,MSR_KERNEL@h
+ ori r3,r3,MSR_KERNEL@l
+ mtspr SPRN_SRR0,r4
+ mtspr SPRN_SRR1,r3
+ rfi /* change context and jump to start_kernel */
+
+/* Macros to hide the PTE size differences
+ *
+ * FIND_PTE -- walks the page tables given EA & pgdir pointer
+ * r10 -- EA of fault
+ * r11 -- PGDIR pointer
+ * r12 -- free
+ * label 2: is the bailout case
+ *
+ * if we find the pte (fall through):
+ * r11 is low pte word
+ * r12 is pointer to the pte
+ * r10 is the pshift from the PGD, if we're a hugepage
+ */
+#ifdef CONFIG_PTE_64BIT
+#ifdef CONFIG_HUGETLB_PAGE
+#define FIND_PTE \
+ rlwinm r12, r10, 13, 19, 29; /* Compute pgdir/pmd offset */ \
+ lwzx r11, r12, r11; /* Get pgd/pmd entry */ \
+ rlwinm. r12, r11, 0, 0, 20; /* Extract pt base address */ \
+ blt 1000f; /* Normal non-huge page */ \
+ beq 2f; /* Bail if no table */ \
+ oris r11, r11, PD_HUGE@h; /* Put back address bit */ \
+ andi. r10, r11, HUGEPD_SHIFT_MASK@l; /* extract size field */ \
+ xor r12, r10, r11; /* drop size bits from pointer */ \
+ b 1001f; \
+1000: rlwimi r12, r10, 23, 20, 28; /* Compute pte address */ \
+ li r10, 0; /* clear r10 */ \
+1001: lwz r11, 4(r12); /* Get pte entry */
+#else
+#define FIND_PTE \
+ rlwinm r12, r10, 13, 19, 29; /* Compute pgdir/pmd offset */ \
+ lwzx r11, r12, r11; /* Get pgd/pmd entry */ \
+ rlwinm. r12, r11, 0, 0, 20; /* Extract pt base address */ \
+ beq 2f; /* Bail if no table */ \
+ rlwimi r12, r10, 23, 20, 28; /* Compute pte address */ \
+ lwz r11, 4(r12); /* Get pte entry */
+#endif /* HUGEPAGE */
+#else /* !PTE_64BIT */
+#define FIND_PTE \
+ rlwimi r11, r10, 12, 20, 29; /* Create L1 (pgdir/pmd) address */ \
+ lwz r11, 0(r11); /* Get L1 entry */ \
+ rlwinm. r12, r11, 0, 0, 19; /* Extract L2 (pte) base address */ \
+ beq 2f; /* Bail if no table */ \
+ rlwimi r12, r10, 22, 20, 29; /* Compute PTE address */ \
+ lwz r11, 0(r12); /* Get Linux PTE */
+#endif
+
+/*
+ * Interrupt vector entry code
+ *
+ * The Book E MMUs are always on so we don't need to handle
+ * interrupts in real mode as with previous PPC processors. In
+ * this case we handle interrupts in the kernel virtual address
+ * space.
+ *
+ * Interrupt vectors are dynamically placed relative to the
+ * interrupt prefix as determined by the address of interrupt_base.
+ * The interrupt vectors offsets are programmed using the labels
+ * for each interrupt vector entry.
+ *
+ * Interrupt vectors must be aligned on a 16 byte boundary.
+ * We align on a 32 byte cache line boundary for good measure.
+ */
+
+interrupt_base:
+ /* Critical Input Interrupt */
+ CRITICAL_EXCEPTION(0x0100, CRITICAL, CriticalInput, unknown_exception)
+
+ /* Machine Check Interrupt */
+ MCHECK_EXCEPTION(0x0200, MachineCheck, machine_check_exception)
+
+ /* Data Storage Interrupt */
+ START_EXCEPTION(DataStorage)
+ NORMAL_EXCEPTION_PROLOG(0x300, DATA_STORAGE)
+ mfspr r5,SPRN_ESR /* Grab the ESR, save it */
+ stw r5,_ESR(r11)
+ mfspr r4,SPRN_DEAR /* Grab the DEAR, save it */
+ stw r4, _DEAR(r11)
+ andis. r10,r5,(ESR_ILK|ESR_DLK)@h
+ bne 1f
+ prepare_transfer_to_handler
+ bl do_page_fault
+ b interrupt_return
+1:
+ prepare_transfer_to_handler
+ bl CacheLockingException
+ b interrupt_return
+
+ /* Instruction Storage Interrupt */
+ INSTRUCTION_STORAGE_EXCEPTION
+
+ /* External Input Interrupt */
+ EXCEPTION(0x0500, EXTERNAL, ExternalInput, do_IRQ)
+
+ /* Alignment Interrupt */
+ ALIGNMENT_EXCEPTION
+
+ /* Program Interrupt */
+ PROGRAM_EXCEPTION
+
+ /* Floating Point Unavailable Interrupt */
+#ifdef CONFIG_PPC_FPU
+ FP_UNAVAILABLE_EXCEPTION
+#else
+ EXCEPTION(0x0800, FP_UNAVAIL, FloatingPointUnavailable, unknown_exception)
+#endif
+
+ /* System Call Interrupt */
+ START_EXCEPTION(SystemCall)
+ SYSCALL_ENTRY 0xc00 BOOKE_INTERRUPT_SYSCALL SPRN_SRR1
+
+ /* Auxiliary Processor Unavailable Interrupt */
+ EXCEPTION(0x2900, AP_UNAVAIL, AuxillaryProcessorUnavailable, unknown_exception)
+
+ /* Decrementer Interrupt */
+ DECREMENTER_EXCEPTION
+
+ /* Fixed Internal Timer Interrupt */
+ /* TODO: Add FIT support */
+ EXCEPTION(0x3100, FIT, FixedIntervalTimer, unknown_exception)
+
+ /* Watchdog Timer Interrupt */
+#ifdef CONFIG_BOOKE_WDT
+ CRITICAL_EXCEPTION(0x3200, WATCHDOG, WatchdogTimer, WatchdogException)
+#else
+ CRITICAL_EXCEPTION(0x3200, WATCHDOG, WatchdogTimer, unknown_exception)
+#endif
+
+ /* Data TLB Error Interrupt */
+ START_EXCEPTION(DataTLBError)
+ mtspr SPRN_SPRG_WSCRATCH0, r10 /* Save some working registers */
+ mfspr r10, SPRN_SPRG_THREAD
+ stw r11, THREAD_NORMSAVE(0)(r10)
+#ifdef CONFIG_KVM_BOOKE_HV
+BEGIN_FTR_SECTION
+ mfspr r11, SPRN_SRR1
+END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
+#endif
+ stw r12, THREAD_NORMSAVE(1)(r10)
+ stw r13, THREAD_NORMSAVE(2)(r10)
+ mfcr r13
+ stw r13, THREAD_NORMSAVE(3)(r10)
+ DO_KVM BOOKE_INTERRUPT_DTLB_MISS SPRN_SRR1
+START_BTB_FLUSH_SECTION
+ mfspr r11, SPRN_SRR1
+ andi. r10,r11,MSR_PR
+ beq 1f
+ BTB_FLUSH(r10)
+1:
+END_BTB_FLUSH_SECTION
+ mfspr r10, SPRN_DEAR /* Get faulting address */
+
+ /* If we are faulting a kernel address, we have to use the
+ * kernel page tables.
+ */
+ lis r11, PAGE_OFFSET@h
+ cmplw 5, r10, r11
+ blt 5, 3f
+ lis r11, swapper_pg_dir@h
+ ori r11, r11, swapper_pg_dir@l
+
+ mfspr r12,SPRN_MAS1 /* Set TID to 0 */
+ rlwinm r12,r12,0,16,1
+ mtspr SPRN_MAS1,r12
+
+ b 4f
+
+ /* Get the PGD for the current thread */
+3:
+ mfspr r11,SPRN_SPRG_THREAD
+ lwz r11,PGDIR(r11)
+
+#ifdef CONFIG_PPC_KUAP
+ mfspr r12, SPRN_MAS1
+ rlwinm. r12,r12,0,0x3fff0000
+ beq 2f /* KUAP fault */
+#endif
+
+4:
+ /* Mask of required permission bits. Note that while we
+ * do copy ESR:ST to _PAGE_RW position as trying to write
+ * to an RO page is pretty common, we don't do it with
+ * _PAGE_DIRTY. We could do it, but it's a fairly rare
+ * event so I'd rather take the overhead when it happens
+ * rather than adding an instruction here. We should measure
+ * whether the whole thing is worth it in the first place
+ * as we could avoid loading SPRN_ESR completely in the first
+ * place...
+ *
+ * TODO: Is it worth doing that mfspr & rlwimi in the first
+ * place or can we save a couple of instructions here ?
+ */
+ mfspr r12,SPRN_ESR
+#ifdef CONFIG_PTE_64BIT
+ li r13,_PAGE_PRESENT
+ oris r13,r13,_PAGE_ACCESSED@h
+#else
+ li r13,_PAGE_PRESENT|_PAGE_ACCESSED
+#endif
+ rlwimi r13,r12,11,29,29
+
+ FIND_PTE
+ andc. r13,r13,r11 /* Check permission */
+
+#ifdef CONFIG_PTE_64BIT
+#ifdef CONFIG_SMP
+ subf r13,r11,r12 /* create false data dep */
+ lwzx r13,r11,r13 /* Get upper pte bits */
+#else
+ lwz r13,0(r12) /* Get upper pte bits */
+#endif
+#endif
+
+ bne 2f /* Bail if permission/valid mismatch */
+
+ /* Jump to common tlb load */
+ b finish_tlb_load
+2:
+ /* The bailout. Restore registers to pre-exception conditions
+ * and call the heavyweights to help us out.
+ */
+ mfspr r10, SPRN_SPRG_THREAD
+ lwz r11, THREAD_NORMSAVE(3)(r10)
+ mtcr r11
+ lwz r13, THREAD_NORMSAVE(2)(r10)
+ lwz r12, THREAD_NORMSAVE(1)(r10)
+ lwz r11, THREAD_NORMSAVE(0)(r10)
+ mfspr r10, SPRN_SPRG_RSCRATCH0
+ b DataStorage
+
+ /* Instruction TLB Error Interrupt */
+ /*
+ * Nearly the same as above, except we get our
+ * information from different registers and bailout
+ * to a different point.
+ */
+ START_EXCEPTION(InstructionTLBError)
+ mtspr SPRN_SPRG_WSCRATCH0, r10 /* Save some working registers */
+ mfspr r10, SPRN_SPRG_THREAD
+ stw r11, THREAD_NORMSAVE(0)(r10)
+#ifdef CONFIG_KVM_BOOKE_HV
+BEGIN_FTR_SECTION
+ mfspr r11, SPRN_SRR1
+END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
+#endif
+ stw r12, THREAD_NORMSAVE(1)(r10)
+ stw r13, THREAD_NORMSAVE(2)(r10)
+ mfcr r13
+ stw r13, THREAD_NORMSAVE(3)(r10)
+ DO_KVM BOOKE_INTERRUPT_ITLB_MISS SPRN_SRR1
+START_BTB_FLUSH_SECTION
+ mfspr r11, SPRN_SRR1
+ andi. r10,r11,MSR_PR
+ beq 1f
+ BTB_FLUSH(r10)
+1:
+END_BTB_FLUSH_SECTION
+
+ mfspr r10, SPRN_SRR0 /* Get faulting address */
+
+ /* If we are faulting a kernel address, we have to use the
+ * kernel page tables.
+ */
+ lis r11, PAGE_OFFSET@h
+ cmplw 5, r10, r11
+ blt 5, 3f
+ lis r11, swapper_pg_dir@h
+ ori r11, r11, swapper_pg_dir@l
+
+ mfspr r12,SPRN_MAS1 /* Set TID to 0 */
+ rlwinm r12,r12,0,16,1
+ mtspr SPRN_MAS1,r12
+
+ /* Make up the required permissions for kernel code */
+#ifdef CONFIG_PTE_64BIT
+ li r13,_PAGE_PRESENT | _PAGE_BAP_SX
+ oris r13,r13,_PAGE_ACCESSED@h
+#else
+ li r13,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC
+#endif
+ b 4f
+
+ /* Get the PGD for the current thread */
+3:
+ mfspr r11,SPRN_SPRG_THREAD
+ lwz r11,PGDIR(r11)
+
+#ifdef CONFIG_PPC_KUAP
+ mfspr r12, SPRN_MAS1
+ rlwinm. r12,r12,0,0x3fff0000
+ beq 2f /* KUAP fault */
+#endif
+
+ /* Make up the required permissions for user code */
+#ifdef CONFIG_PTE_64BIT
+ li r13,_PAGE_PRESENT | _PAGE_BAP_UX
+ oris r13,r13,_PAGE_ACCESSED@h
+#else
+ li r13,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC
+#endif
+
+4:
+ FIND_PTE
+ andc. r13,r13,r11 /* Check permission */
+
+#ifdef CONFIG_PTE_64BIT
+#ifdef CONFIG_SMP
+ subf r13,r11,r12 /* create false data dep */
+ lwzx r13,r11,r13 /* Get upper pte bits */
+#else
+ lwz r13,0(r12) /* Get upper pte bits */
+#endif
+#endif
+
+ bne 2f /* Bail if permission mismatch */
+
+ /* Jump to common TLB load point */
+ b finish_tlb_load
+
+2:
+ /* The bailout. Restore registers to pre-exception conditions
+ * and call the heavyweights to help us out.
+ */
+ mfspr r10, SPRN_SPRG_THREAD
+ lwz r11, THREAD_NORMSAVE(3)(r10)
+ mtcr r11
+ lwz r13, THREAD_NORMSAVE(2)(r10)
+ lwz r12, THREAD_NORMSAVE(1)(r10)
+ lwz r11, THREAD_NORMSAVE(0)(r10)
+ mfspr r10, SPRN_SPRG_RSCRATCH0
+ b InstructionStorage
+
+/* Define SPE handlers for e500v2 */
+#ifdef CONFIG_SPE
+ /* SPE Unavailable */
+ START_EXCEPTION(SPEUnavailable)
+ NORMAL_EXCEPTION_PROLOG(0x2010, SPE_UNAVAIL)
+ beq 1f
+ bl load_up_spe
+ b fast_exception_return
+1: prepare_transfer_to_handler
+ bl KernelSPE
+ b interrupt_return
+#elif defined(CONFIG_SPE_POSSIBLE)
+ EXCEPTION(0x2020, SPE_UNAVAIL, SPEUnavailable, unknown_exception)
+#endif /* CONFIG_SPE_POSSIBLE */
+
+ /* SPE Floating Point Data */
+#ifdef CONFIG_SPE
+ START_EXCEPTION(SPEFloatingPointData)
+ NORMAL_EXCEPTION_PROLOG(0x2030, SPE_FP_DATA)
+ prepare_transfer_to_handler
+ bl SPEFloatingPointException
+ REST_NVGPRS(r1)
+ b interrupt_return
+
+ /* SPE Floating Point Round */
+ START_EXCEPTION(SPEFloatingPointRound)
+ NORMAL_EXCEPTION_PROLOG(0x2050, SPE_FP_ROUND)
+ prepare_transfer_to_handler
+ bl SPEFloatingPointRoundException
+ REST_NVGPRS(r1)
+ b interrupt_return
+#elif defined(CONFIG_SPE_POSSIBLE)
+ EXCEPTION(0x2040, SPE_FP_DATA, SPEFloatingPointData, unknown_exception)
+ EXCEPTION(0x2050, SPE_FP_ROUND, SPEFloatingPointRound, unknown_exception)
+#endif /* CONFIG_SPE_POSSIBLE */
+
+
+ /* Performance Monitor */
+ EXCEPTION(0x2060, PERFORMANCE_MONITOR, PerformanceMonitor, \
+ performance_monitor_exception)
+
+ EXCEPTION(0x2070, DOORBELL, Doorbell, doorbell_exception)
+
+ CRITICAL_EXCEPTION(0x2080, DOORBELL_CRITICAL, \
+ CriticalDoorbell, unknown_exception)
+
+ /* Debug Interrupt */
+ DEBUG_DEBUG_EXCEPTION
+ DEBUG_CRIT_EXCEPTION
+
+ GUEST_DOORBELL_EXCEPTION
+
+ CRITICAL_EXCEPTION(0, GUEST_DBELL_CRIT, CriticalGuestDoorbell, \
+ unknown_exception)
+
+ /* Hypercall */
+ EXCEPTION(0, HV_SYSCALL, Hypercall, unknown_exception)
+
+ /* Embedded Hypervisor Privilege */
+ EXCEPTION(0, HV_PRIV, Ehvpriv, unknown_exception)
+
+interrupt_end:
+
+/*
+ * Local functions
+ */
+
+/*
+ * Both the instruction and data TLB miss get to this
+ * point to load the TLB.
+ * r10 - tsize encoding (if HUGETLB_PAGE) or available to use
+ * r11 - TLB (info from Linux PTE)
+ * r12 - available to use
+ * r13 - upper bits of PTE (if PTE_64BIT) or available to use
+ * CR5 - results of addr >= PAGE_OFFSET
+ * MAS0, MAS1 - loaded with proper value when we get here
+ * MAS2, MAS3 - will need additional info from Linux PTE
+ * Upon exit, we reload everything and RFI.
+ */
+finish_tlb_load:
+#ifdef CONFIG_HUGETLB_PAGE
+ cmpwi 6, r10, 0 /* check for huge page */
+ beq 6, finish_tlb_load_cont /* !huge */
+
+ /* Alas, we need more scratch registers for hugepages */
+ mfspr r12, SPRN_SPRG_THREAD
+ stw r14, THREAD_NORMSAVE(4)(r12)
+ stw r15, THREAD_NORMSAVE(5)(r12)
+ stw r16, THREAD_NORMSAVE(6)(r12)
+ stw r17, THREAD_NORMSAVE(7)(r12)
+
+ /* Get the next_tlbcam_idx percpu var */
+#ifdef CONFIG_SMP
+ lwz r15, TASK_CPU-THREAD(r12)
+ lis r14, __per_cpu_offset@h
+ ori r14, r14, __per_cpu_offset@l
+ rlwinm r15, r15, 2, 0, 29
+ lwzx r16, r14, r15
+#else
+ li r16, 0
+#endif
+ lis r17, next_tlbcam_idx@h
+ ori r17, r17, next_tlbcam_idx@l
+ add r17, r17, r16 /* r17 = *next_tlbcam_idx */
+ lwz r15, 0(r17) /* r15 = next_tlbcam_idx */
+
+ lis r14, MAS0_TLBSEL(1)@h /* select TLB1 (TLBCAM) */
+ rlwimi r14, r15, 16, 4, 15 /* next_tlbcam_idx entry */
+ mtspr SPRN_MAS0, r14
+
+ /* Extract TLB1CFG(NENTRY) */
+ mfspr r16, SPRN_TLB1CFG
+ andi. r16, r16, 0xfff
+
+ /* Update next_tlbcam_idx, wrapping when necessary */
+ addi r15, r15, 1
+ cmpw r15, r16
+ blt 100f
+ lis r14, tlbcam_index@h
+ ori r14, r14, tlbcam_index@l
+ lwz r15, 0(r14)
+100: stw r15, 0(r17)
+
+ /*
+ * Calc MAS1_TSIZE from r10 (which has pshift encoded)
+ * tlb_enc = (pshift - 10).
+ */
+ subi r15, r10, 10
+ mfspr r16, SPRN_MAS1
+ rlwimi r16, r15, 7, 20, 24
+ mtspr SPRN_MAS1, r16
+
+ /* copy the pshift for use later */
+ mr r14, r10
+
+ /* fall through */
+
+#endif /* CONFIG_HUGETLB_PAGE */
+
+ /*
+ * We set execute, because we don't have the granularity to
+ * properly set this at the page level (Linux problem).
+ * Many of these bits are software only. Bits we don't set
+ * here we (properly should) assume have the appropriate value.
+ */
+finish_tlb_load_cont:
+#ifdef CONFIG_PTE_64BIT
+ rlwinm r12, r11, 32-2, 26, 31 /* Move in perm bits */
+ andi. r10, r11, _PAGE_DIRTY
+ bne 1f
+ li r10, MAS3_SW | MAS3_UW
+ andc r12, r12, r10
+1: rlwimi r12, r13, 20, 0, 11 /* grab RPN[32:43] */
+ rlwimi r12, r11, 20, 12, 19 /* grab RPN[44:51] */
+2: mtspr SPRN_MAS3, r12
+BEGIN_MMU_FTR_SECTION
+ srwi r10, r13, 12 /* grab RPN[12:31] */
+ mtspr SPRN_MAS7, r10
+END_MMU_FTR_SECTION_IFSET(MMU_FTR_BIG_PHYS)
+#else
+ li r10, (_PAGE_EXEC | _PAGE_PRESENT)
+ mr r13, r11
+ rlwimi r10, r11, 31, 29, 29 /* extract _PAGE_DIRTY into SW */
+ and r12, r11, r10
+ andi. r10, r11, _PAGE_USER /* Test for _PAGE_USER */
+ slwi r10, r12, 1
+ or r10, r10, r12
+ rlwinm r10, r10, 0, ~_PAGE_EXEC /* Clear SX on user pages */
+ iseleq r12, r12, r10
+ rlwimi r13, r12, 0, 20, 31 /* Get RPN from PTE, merge w/ perms */
+ mtspr SPRN_MAS3, r13
+#endif
+
+ mfspr r12, SPRN_MAS2
+#ifdef CONFIG_PTE_64BIT
+ rlwimi r12, r11, 32-19, 27, 31 /* extract WIMGE from pte */
+#else
+ rlwimi r12, r11, 26, 27, 31 /* extract WIMGE from pte */
+#endif
+#ifdef CONFIG_HUGETLB_PAGE
+ beq 6, 3f /* don't mask if page isn't huge */
+ li r13, 1
+ slw r13, r13, r14
+ subi r13, r13, 1
+ rlwinm r13, r13, 0, 0, 19 /* bottom bits used for WIMGE/etc */
+ andc r12, r12, r13 /* mask off ea bits within the page */
+#endif
+3: mtspr SPRN_MAS2, r12
+
+tlb_write_entry:
+ tlbwe
+
+ /* Done...restore registers and get out of here. */
+ mfspr r10, SPRN_SPRG_THREAD
+#ifdef CONFIG_HUGETLB_PAGE
+ beq 6, 8f /* skip restore for 4k page faults */
+ lwz r14, THREAD_NORMSAVE(4)(r10)
+ lwz r15, THREAD_NORMSAVE(5)(r10)
+ lwz r16, THREAD_NORMSAVE(6)(r10)
+ lwz r17, THREAD_NORMSAVE(7)(r10)
+#endif
+8: lwz r11, THREAD_NORMSAVE(3)(r10)
+ mtcr r11
+ lwz r13, THREAD_NORMSAVE(2)(r10)
+ lwz r12, THREAD_NORMSAVE(1)(r10)
+ lwz r11, THREAD_NORMSAVE(0)(r10)
+ mfspr r10, SPRN_SPRG_RSCRATCH0
+ rfi /* Force context change */
+
+#ifdef CONFIG_SPE
+/* Note that the SPE support is closely modeled after the AltiVec
+ * support. Changes to one are likely to be applicable to the
+ * other! */
+_GLOBAL(load_up_spe)
+/*
+ * Disable SPE for the task which had SPE previously,
+ * and save its SPE registers in its thread_struct.
+ * Enables SPE for use in the kernel on return.
+ * On SMP we know the SPE units are free, since we give it up every
+ * switch. -- Kumar
+ */
+ mfmsr r5
+ oris r5,r5,MSR_SPE@h
+ mtmsr r5 /* enable use of SPE now */
+ isync
+ /* enable use of SPE after return */
+ oris r9,r9,MSR_SPE@h
+ mfspr r5,SPRN_SPRG_THREAD /* current task's THREAD (phys) */
+ li r4,1
+ li r10,THREAD_ACC
+ stw r4,THREAD_USED_SPE(r5)
+ evlddx evr4,r10,r5
+ evmra evr4,evr4
+ REST_32EVRS(0,r10,r5,THREAD_EVR0)
+ blr
+
+/*
+ * SPE unavailable trap from kernel - print a message, but let
+ * the task use SPE in the kernel until it returns to user mode.
+ */
+KernelSPE:
+ lwz r3,_MSR(r1)
+ oris r3,r3,MSR_SPE@h
+ stw r3,_MSR(r1) /* enable use of SPE after return */
+#ifdef CONFIG_PRINTK
+ lis r3,87f@h
+ ori r3,r3,87f@l
+ mr r4,r2 /* current */
+ lwz r5,_NIP(r1)
+ bl _printk
+#endif
+ b interrupt_return
+#ifdef CONFIG_PRINTK
+87: .string "SPE used in kernel (task=%p, pc=%x) \n"
+#endif
+ .align 4,0
+
+#endif /* CONFIG_SPE */
+
+/*
+ * Translate the effec addr in r3 to phys addr. The phys addr will be put
+ * into r3(higher 32bit) and r4(lower 32bit)
+ */
+get_phys_addr:
+ mfmsr r8
+ mfspr r9,SPRN_PID
+ rlwinm r9,r9,16,0x3fff0000 /* turn PID into MAS6[SPID] */
+ rlwimi r9,r8,28,0x00000001 /* turn MSR[DS] into MAS6[SAS] */
+ mtspr SPRN_MAS6,r9
+
+ tlbsx 0,r3 /* must succeed */
+
+ mfspr r8,SPRN_MAS1
+ mfspr r12,SPRN_MAS3
+ rlwinm r9,r8,25,0x1f /* r9 = log2(page size) */
+ li r10,1024
+ slw r10,r10,r9 /* r10 = page size */
+ addi r10,r10,-1
+ and r11,r3,r10 /* r11 = page offset */
+ andc r4,r12,r10 /* r4 = page base */
+ or r4,r4,r11 /* r4 = devtree phys addr */
+#ifdef CONFIG_PHYS_64BIT
+ mfspr r3,SPRN_MAS7
+#endif
+ blr
+
+/*
+ * Global functions
+ */
+
+#ifdef CONFIG_PPC_E500
+#ifndef CONFIG_PPC_E500MC
+/* Adjust or setup IVORs for e500v1/v2 */
+_GLOBAL(__setup_e500_ivors)
+ li r3,DebugCrit@l
+ mtspr SPRN_IVOR15,r3
+ li r3,SPEUnavailable@l
+ mtspr SPRN_IVOR32,r3
+ li r3,SPEFloatingPointData@l
+ mtspr SPRN_IVOR33,r3
+ li r3,SPEFloatingPointRound@l
+ mtspr SPRN_IVOR34,r3
+ li r3,PerformanceMonitor@l
+ mtspr SPRN_IVOR35,r3
+ sync
+ blr
+#else
+/* Adjust or setup IVORs for e500mc */
+_GLOBAL(__setup_e500mc_ivors)
+ li r3,DebugDebug@l
+ mtspr SPRN_IVOR15,r3
+ li r3,PerformanceMonitor@l
+ mtspr SPRN_IVOR35,r3
+ li r3,Doorbell@l
+ mtspr SPRN_IVOR36,r3
+ li r3,CriticalDoorbell@l
+ mtspr SPRN_IVOR37,r3
+ sync
+ blr
+
+/* setup ehv ivors for */
+_GLOBAL(__setup_ehv_ivors)
+ li r3,GuestDoorbell@l
+ mtspr SPRN_IVOR38,r3
+ li r3,CriticalGuestDoorbell@l
+ mtspr SPRN_IVOR39,r3
+ li r3,Hypercall@l
+ mtspr SPRN_IVOR40,r3
+ li r3,Ehvpriv@l
+ mtspr SPRN_IVOR41,r3
+ sync
+ blr
+#endif /* CONFIG_PPC_E500MC */
+#endif /* CONFIG_PPC_E500 */
+
+#ifdef CONFIG_SPE
+/*
+ * extern void __giveup_spe(struct task_struct *prev)
+ *
+ */
+_GLOBAL(__giveup_spe)
+ addi r3,r3,THREAD /* want THREAD of task */
+ lwz r5,PT_REGS(r3)
+ cmpi 0,r5,0
+ SAVE_32EVRS(0, r4, r3, THREAD_EVR0)
+ evxor evr6, evr6, evr6 /* clear out evr6 */
+ evmwumiaa evr6, evr6, evr6 /* evr6 <- ACC = 0 * 0 + ACC */
+ li r4,THREAD_ACC
+ evstddx evr6, r4, r3 /* save off accumulator */
+ beq 1f
+ lwz r4,_MSR-STACK_FRAME_OVERHEAD(r5)
+ lis r3,MSR_SPE@h
+ andc r4,r4,r3 /* disable SPE for previous task */
+ stw r4,_MSR-STACK_FRAME_OVERHEAD(r5)
+1:
+ blr
+#endif /* CONFIG_SPE */
+
+/*
+ * extern void abort(void)
+ *
+ * At present, this routine just applies a system reset.
+ */
+_GLOBAL(abort)
+ li r13,0
+ mtspr SPRN_DBCR0,r13 /* disable all debug events */
+ isync
+ mfmsr r13
+ ori r13,r13,MSR_DE@l /* Enable Debug Events */
+ mtmsr r13
+ isync
+ mfspr r13,SPRN_DBCR0
+ lis r13,(DBCR0_IDM|DBCR0_RST_CHIP)@h
+ mtspr SPRN_DBCR0,r13
+ isync
+
+#ifdef CONFIG_SMP
+/* When we get here, r24 needs to hold the CPU # */
+ .globl __secondary_start
+__secondary_start:
+ LOAD_REG_ADDR_PIC(r3, tlbcam_index)
+ lwz r3,0(r3)
+ mtctr r3
+ li r26,0 /* r26 safe? */
+
+ bl switch_to_as1
+ mr r27,r3 /* tlb entry */
+ /* Load each CAM entry */
+1: mr r3,r26
+ bl loadcam_entry
+ addi r26,r26,1
+ bdnz 1b
+ mr r3,r27 /* tlb entry */
+ LOAD_REG_ADDR_PIC(r4, memstart_addr)
+ lwz r4,0(r4)
+ mr r5,r25 /* phys kernel start */
+ rlwinm r5,r5,0,~0x3ffffff /* aligned 64M */
+ subf r4,r5,r4 /* memstart_addr - phys kernel start */
+ lis r7,KERNELBASE@h
+ ori r7,r7,KERNELBASE@l
+ cmpw r20,r7 /* if kernstart_virt_addr != KERNELBASE, randomized */
+ beq 2f
+ li r4,0
+2: li r5,0 /* no device tree */
+ li r6,0 /* not boot cpu */
+ bl restore_to_as0
+
+
+ lis r3,__secondary_hold_acknowledge@h
+ ori r3,r3,__secondary_hold_acknowledge@l
+ stw r24,0(r3)
+
+ li r3,0
+ mr r4,r24 /* Why? */
+ bl call_setup_cpu
+
+ /* get current's stack and current */
+ lis r2,secondary_current@ha
+ lwz r2,secondary_current@l(r2)
+ lwz r1,TASK_STACK(r2)
+
+ /* stack */
+ addi r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD
+ li r0,0
+ stw r0,0(r1)
+
+ /* ptr to current thread */
+ addi r4,r2,THREAD /* address of our thread_struct */
+ mtspr SPRN_SPRG_THREAD,r4
+
+ /* Setup the defaults for TLB entries */
+ li r4,(MAS4_TSIZED(BOOK3E_PAGESZ_4K))@l
+ mtspr SPRN_MAS4,r4
+
+ /* Jump to start_secondary */
+ lis r4,MSR_KERNEL@h
+ ori r4,r4,MSR_KERNEL@l
+ lis r3,start_secondary@h
+ ori r3,r3,start_secondary@l
+ mtspr SPRN_SRR0,r3
+ mtspr SPRN_SRR1,r4
+ sync
+ rfi
+ sync
+
+ .globl __secondary_hold_acknowledge
+__secondary_hold_acknowledge:
+ .long -1
+#endif
+
+/*
+ * Create a 64M tlb by address and entry
+ * r3 - entry
+ * r4 - virtual address
+ * r5/r6 - physical address
+ */
+_GLOBAL(create_kaslr_tlb_entry)
+ lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */
+ rlwimi r7,r3,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r6) */
+ mtspr SPRN_MAS0,r7 /* Write MAS0 */
+
+ lis r3,(MAS1_VALID|MAS1_IPROT)@h
+ ori r3,r3,(MAS1_TSIZE(BOOK3E_PAGESZ_64M))@l
+ mtspr SPRN_MAS1,r3 /* Write MAS1 */
+
+ lis r3,MAS2_EPN_MASK(BOOK3E_PAGESZ_64M)@h
+ ori r3,r3,MAS2_EPN_MASK(BOOK3E_PAGESZ_64M)@l
+ and r3,r3,r4
+ ori r3,r3,MAS2_M_IF_NEEDED@l
+ mtspr SPRN_MAS2,r3 /* Write MAS2(EPN) */
+
+#ifdef CONFIG_PHYS_64BIT
+ ori r8,r6,(MAS3_SW|MAS3_SR|MAS3_SX)
+ mtspr SPRN_MAS3,r8 /* Write MAS3(RPN) */
+ mtspr SPRN_MAS7,r5
+#else
+ ori r8,r5,(MAS3_SW|MAS3_SR|MAS3_SX)
+ mtspr SPRN_MAS3,r8 /* Write MAS3(RPN) */
+#endif
+
+ tlbwe /* Write TLB */
+ isync
+ sync
+ blr
+
+/*
+ * Return to the start of the relocated kernel and run again
+ * r3 - virtual address of fdt
+ * r4 - entry of the kernel
+ */
+_GLOBAL(reloc_kernel_entry)
+ mfmsr r7
+ rlwinm r7, r7, 0, ~(MSR_IS | MSR_DS)
+
+ mtspr SPRN_SRR0,r4
+ mtspr SPRN_SRR1,r7
+ rfi
+
+/*
+ * Create a tlb entry with the same effective and physical address as
+ * the tlb entry used by the current running code. But set the TS to 1.
+ * Then switch to the address space 1. It will return with the r3 set to
+ * the ESEL of the new created tlb.
+ */
+_GLOBAL(switch_to_as1)
+ mflr r5
+
+ /* Find a entry not used */
+ mfspr r3,SPRN_TLB1CFG
+ andi. r3,r3,0xfff
+ mfspr r4,SPRN_PID
+ rlwinm r4,r4,16,0x3fff0000 /* turn PID into MAS6[SPID] */
+ mtspr SPRN_MAS6,r4
+1: lis r4,0x1000 /* Set MAS0(TLBSEL) = 1 */
+ addi r3,r3,-1
+ rlwimi r4,r3,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r3) */
+ mtspr SPRN_MAS0,r4
+ tlbre
+ mfspr r4,SPRN_MAS1
+ andis. r4,r4,MAS1_VALID@h
+ bne 1b
+
+ /* Get the tlb entry used by the current running code */
+ bcl 20,31,$+4
+0: mflr r4
+ tlbsx 0,r4
+
+ mfspr r4,SPRN_MAS1
+ ori r4,r4,MAS1_TS /* Set the TS = 1 */
+ mtspr SPRN_MAS1,r4
+
+ mfspr r4,SPRN_MAS0
+ rlwinm r4,r4,0,~MAS0_ESEL_MASK
+ rlwimi r4,r3,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r3) */
+ mtspr SPRN_MAS0,r4
+ tlbwe
+ isync
+ sync
+
+ mfmsr r4
+ ori r4,r4,MSR_IS | MSR_DS
+ mtspr SPRN_SRR0,r5
+ mtspr SPRN_SRR1,r4
+ sync
+ rfi
+
+/*
+ * Restore to the address space 0 and also invalidate the tlb entry created
+ * by switch_to_as1.
+ * r3 - the tlb entry which should be invalidated
+ * r4 - __pa(PAGE_OFFSET in AS1) - __pa(PAGE_OFFSET in AS0)
+ * r5 - device tree virtual address. If r4 is 0, r5 is ignored.
+ * r6 - boot cpu
+*/
+_GLOBAL(restore_to_as0)
+ mflr r0
+
+ bcl 20,31,$+4
+0: mflr r9
+ addi r9,r9,1f - 0b
+
+ /*
+ * We may map the PAGE_OFFSET in AS0 to a different physical address,
+ * so we need calculate the right jump and device tree address based
+ * on the offset passed by r4.
+ */
+ add r9,r9,r4
+ add r5,r5,r4
+ add r0,r0,r4
+
+2: mfmsr r7
+ li r8,(MSR_IS | MSR_DS)
+ andc r7,r7,r8
+
+ mtspr SPRN_SRR0,r9
+ mtspr SPRN_SRR1,r7
+ sync
+ rfi
+
+ /* Invalidate the temporary tlb entry for AS1 */
+1: lis r9,0x1000 /* Set MAS0(TLBSEL) = 1 */
+ rlwimi r9,r3,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r3) */
+ mtspr SPRN_MAS0,r9
+ tlbre
+ mfspr r9,SPRN_MAS1
+ rlwinm r9,r9,0,2,31 /* Clear MAS1 Valid and IPPROT */
+ mtspr SPRN_MAS1,r9
+ tlbwe
+ isync
+
+ cmpwi r4,0
+ cmpwi cr1,r6,0
+ cror eq,4*cr1+eq,eq
+ bne 3f /* offset != 0 && is_boot_cpu */
+ mtlr r0
+ blr
+
+ /*
+ * The PAGE_OFFSET will map to a different physical address,
+ * jump to _start to do another relocation again.
+ */
+3: mr r3,r5
+ bl _start