Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1282 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
new file mode 100644
index 000000000..61ca27929
--- /dev/null
+++ b/arch/powerpc/kernel/head_32.S
@@ -0,0 +1,1282 @@
+/*
+ *  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.
+ *  MPC8xx modifications Copyright (C) 1997 Dan Malek (dmalek@jlc.net).
+ *
+ *  This file contains the low-level support and setup for the
+ *  PowerPC platform, including trap and interrupt dispatch.
+ *  (The PPC 8xx embedded CPUs use head_8xx.S instead.)
+ *
+ *  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/init.h>
+#include <asm/reg.h>
+#include <asm/page.h>
+#include <asm/mmu.h>
+#include <asm/pgtable.h>
+#include <asm/cputable.h>
+#include <asm/cache.h>
+#include <asm/thread_info.h>
+#include <asm/ppc_asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/ptrace.h>
+#include <asm/bug.h>
+#include <asm/kvm_book3s_asm.h>
+#include <asm/export.h>
+#include <asm/feature-fixups.h>
+
+/* 601 only have IBAT; cr0.eq is set on 601 when using this macro */
+#define LOAD_BAT(n, reg, RA, RB)	\
+	/* see the comment for clear_bats() -- Cort */ \
+	li	RA,0;			\
+	mtspr	SPRN_IBAT##n##U,RA;	\
+	mtspr	SPRN_DBAT##n##U,RA;	\
+	lwz	RA,(n*16)+0(reg);	\
+	lwz	RB,(n*16)+4(reg);	\
+	mtspr	SPRN_IBAT##n##U,RA;	\
+	mtspr	SPRN_IBAT##n##L,RB;	\
+	beq	1f;			\
+	lwz	RA,(n*16)+8(reg);	\
+	lwz	RB,(n*16)+12(reg);	\
+	mtspr	SPRN_DBAT##n##U,RA;	\
+	mtspr	SPRN_DBAT##n##L,RB;	\
+1:
+
+	__HEAD
+	.stabs	"arch/powerpc/kernel/",N_SO,0,0,0f
+	.stabs	"head_32.S",N_SO,0,0,0f
+0:
+_ENTRY(_stext);
+
+/*
+ * _start is defined this way because the XCOFF loader in the OpenFirmware
+ * on the powermac expects the entry point to be a procedure descriptor.
+ */
+_ENTRY(_start);
+	/*
+	 * These are here for legacy reasons, the kernel used to
+	 * need to look like a coff function entry for the pmac
+	 * but we're always started by some kind of bootloader now.
+	 *  -- Cort
+	 */
+	nop	/* used by __secondary_hold on prep (mtx) and chrp smp */
+	nop	/* used by __secondary_hold on prep (mtx) and chrp smp */
+	nop
+
+/* PMAC
+ * Enter here with the kernel text, data and bss loaded starting at
+ * 0, running with virtual == physical mapping.
+ * r5 points to the prom entry point (the client interface handler
+ * address).  Address translation is turned on, with the prom
+ * managing the hash table.  Interrupts are disabled.  The stack
+ * pointer (r1) points to just below the end of the half-meg region
+ * from 0x380000 - 0x400000, which is mapped in already.
+ *
+ * If we are booted from MacOS via BootX, we enter with the kernel
+ * image loaded somewhere, and the following values in registers:
+ *  r3: 'BooX' (0x426f6f58)
+ *  r4: virtual address of boot_infos_t
+ *  r5: 0
+ *
+ * PREP
+ * This is jumped to on prep systems right after the kernel is relocated
+ * to its proper place in memory by the boot loader.  The expected layout
+ * of the regs is:
+ *   r3: ptr to residual data
+ *   r4: initrd_start or if no initrd then 0
+ *   r5: initrd_end - unused if r4 is 0
+ *   r6: Start of command line string
+ *   r7: End of command line string
+ *
+ * This just gets a minimal mmu environment setup so we can call
+ * start_here() to do the real work.
+ * -- Cort
+ */
+
+	.globl	__start
+__start:
+/*
+ * We have to do any OF calls before we map ourselves to KERNELBASE,
+ * because OF may have I/O devices mapped into that area
+ * (particularly on CHRP).
+ */
+	cmpwi	0,r5,0
+	beq	1f
+
+#ifdef CONFIG_PPC_OF_BOOT_TRAMPOLINE
+	/* find out where we are now */
+	bcl	20,31,$+4
+0:	mflr	r8			/* r8 = runtime addr here */
+	addis	r8,r8,(_stext - 0b)@ha
+	addi	r8,r8,(_stext - 0b)@l	/* current runtime base addr */
+	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
+
+/*
+ * Check for BootX signature when supporting PowerMac and branch to
+ * appropriate trampoline if it's present
+ */
+#ifdef CONFIG_PPC_PMAC
+1:	lis	r31,0x426f
+	ori	r31,r31,0x6f58
+	cmpw	0,r3,r31
+	bne	1f
+	bl	bootx_init
+	trap
+#endif /* CONFIG_PPC_PMAC */
+
+1:	mr	r31,r3			/* save device tree ptr */
+	li	r24,0			/* cpu # */
+
+/*
+ * early_init() does the early machine identification and does
+ * the necessary low-level setup and clears the BSS
+ *  -- Cort <cort@fsmlabs.com>
+ */
+	bl	early_init
+
+/* Switch MMU off, clear BATs and flush TLB. At this point, r3 contains
+ * the physical address we are running at, returned by early_init()
+ */
+ 	bl	mmu_off
+__after_mmu_off:
+	bl	clear_bats
+	bl	flush_tlbs
+
+	bl	initial_bats
+#if defined(CONFIG_BOOTX_TEXT)
+	bl	setup_disp_bat
+#endif
+#ifdef CONFIG_PPC_EARLY_DEBUG_CPM
+	bl	setup_cpm_bat
+#endif
+#ifdef CONFIG_PPC_EARLY_DEBUG_USBGECKO
+	bl	setup_usbgecko_bat
+#endif
+
+/*
+ * Call setup_cpu for CPU 0 and initialize 6xx Idle
+ */
+	bl	reloc_offset
+	li	r24,0			/* cpu# */
+	bl	call_setup_cpu		/* Call setup_cpu for this CPU */
+#ifdef CONFIG_6xx
+	bl	reloc_offset
+	bl	init_idle_6xx
+#endif /* CONFIG_6xx */
+
+
+/*
+ * We need to run with _start at physical address 0.
+ * On CHRP, we are loaded at 0x10000 since OF on CHRP uses
+ * the exception vectors at 0 (and therefore this copy
+ * overwrites OF's exception vectors with our own).
+ * The MMU is off at this point.
+ */
+	bl	reloc_offset
+	mr	r26,r3
+	addis	r4,r3,KERNELBASE@h	/* current address of _start */
+	lis	r5,PHYSICAL_START@h
+	cmplw	0,r4,r5			/* already running at PHYSICAL_START? */
+	bne	relocate_kernel
+/*
+ * we now have the 1st 16M of ram mapped with the bats.
+ * prep needs the mmu to be turned on here, but pmac already has it on.
+ * this shouldn't bother the pmac since it just gets turned on again
+ * as we jump to our code at KERNELBASE. -- Cort
+ * Actually no, pmac doesn't have it on any more. BootX enters with MMU
+ * off, and in other cases, we now turn it off before changing BATs above.
+ */
+turn_on_mmu:
+	mfmsr	r0
+	ori	r0,r0,MSR_DR|MSR_IR
+	mtspr	SPRN_SRR1,r0
+	lis	r0,start_here@h
+	ori	r0,r0,start_here@l
+	mtspr	SPRN_SRR0,r0
+	SYNC
+	RFI				/* enables MMU */
+
+/*
+ * We need __secondary_hold as a place to hold the other cpus on
+ * an SMP machine, even when we are running a UP kernel.
+ */
+	. = 0xc0			/* for prep bootloader */
+	li	r3,1			/* MTX only has 1 cpu */
+	.globl	__secondary_hold
+__secondary_hold:
+	/* tell the master we're here */
+	stw	r3,__secondary_hold_acknowledge@l(0)
+#ifdef CONFIG_SMP
+100:	lwz	r4,0(0)
+	/* wait until we're told to start */
+	cmpw	0,r4,r3
+	bne	100b
+	/* our cpu # was at addr 0 - go */
+	mr	r24,r3			/* cpu # */
+	b	__secondary_start
+#else
+	b	.
+#endif /* CONFIG_SMP */
+
+	.globl	__secondary_hold_spinloop
+__secondary_hold_spinloop:
+	.long	0
+	.globl	__secondary_hold_acknowledge
+__secondary_hold_acknowledge:
+	.long	-1
+
+/*
+ * Exception entry code.  This code runs with address translation
+ * turned off, i.e. using physical addresses.
+ * We assume sprg3 has the physical address of the current
+ * task's thread_struct.
+ */
+#define EXCEPTION_PROLOG	\
+	mtspr	SPRN_SPRG_SCRATCH0,r10;	\
+	mtspr	SPRN_SPRG_SCRATCH1,r11;	\
+	mfcr	r10;		\
+	EXCEPTION_PROLOG_1;	\
+	EXCEPTION_PROLOG_2
+
+#define EXCEPTION_PROLOG_1	\
+	mfspr	r11,SPRN_SRR1;		/* check whether user or kernel */ \
+	andi.	r11,r11,MSR_PR;	\
+	tophys(r11,r1);			/* use tophys(r1) if kernel */ \
+	beq	1f;		\
+	mfspr	r11,SPRN_SPRG_THREAD;	\
+	lwz	r11,THREAD_INFO-THREAD(r11);	\
+	addi	r11,r11,THREAD_SIZE;	\
+	tophys(r11,r11);	\
+1:	subi	r11,r11,INT_FRAME_SIZE	/* alloc exc. frame */
+
+
+#define EXCEPTION_PROLOG_2	\
+	stw	r10,_CCR(r11);		/* save registers */ \
+	stw	r12,GPR12(r11);	\
+	stw	r9,GPR9(r11);	\
+	mfspr	r10,SPRN_SPRG_SCRATCH0;	\
+	stw	r10,GPR10(r11);	\
+	mfspr	r12,SPRN_SPRG_SCRATCH1;	\
+	stw	r12,GPR11(r11);	\
+	mflr	r10;		\
+	stw	r10,_LINK(r11);	\
+	mfspr	r12,SPRN_SRR0;	\
+	mfspr	r9,SPRN_SRR1;	\
+	stw	r1,GPR1(r11);	\
+	stw	r1,0(r11);	\
+	tovirt(r1,r11);			/* set new kernel sp */	\
+	li	r10,MSR_KERNEL & ~(MSR_IR|MSR_DR); /* can take exceptions */ \
+	MTMSRD(r10);			/* (except for mach check in rtas) */ \
+	stw	r0,GPR0(r11);	\
+	lis	r10,STACK_FRAME_REGS_MARKER@ha; /* exception frame marker */ \
+	addi	r10,r10,STACK_FRAME_REGS_MARKER@l; \
+	stw	r10,8(r11);	\
+	SAVE_4GPRS(3, r11);	\
+	SAVE_2GPRS(7, r11)
+
+/*
+ * Note: code which follows this uses cr0.eq (set if from kernel),
+ * r11, r12 (SRR0), and r9 (SRR1).
+ *
+ * Note2: once we have set r1 we are in a position to take exceptions
+ * again, and we could thus set MSR:RI at that point.
+ */
+
+/*
+ * Exception vectors.
+ */
+#define EXCEPTION(n, label, hdlr, xfer)		\
+	. = n;					\
+	DO_KVM n;				\
+label:						\
+	EXCEPTION_PROLOG;			\
+	addi	r3,r1,STACK_FRAME_OVERHEAD;	\
+	xfer(n, hdlr)
+
+#define EXC_XFER_TEMPLATE(n, hdlr, trap, copyee, tfer, ret)	\
+	li	r10,trap;					\
+	stw	r10,_TRAP(r11);					\
+	li	r10,MSR_KERNEL;					\
+	copyee(r10, r9);					\
+	bl	tfer;						\
+i##n:								\
+	.long	hdlr;						\
+	.long	ret
+
+#define COPY_EE(d, s)		rlwimi d,s,0,16,16
+#define NOCOPY(d, s)
+
+#define EXC_XFER_STD(n, hdlr)		\
+	EXC_XFER_TEMPLATE(n, hdlr, n, NOCOPY, transfer_to_handler_full,	\
+			  ret_from_except_full)
+
+#define EXC_XFER_LITE(n, hdlr)		\
+	EXC_XFER_TEMPLATE(n, hdlr, n+1, NOCOPY, transfer_to_handler, \
+			  ret_from_except)
+
+#define EXC_XFER_EE(n, hdlr)		\
+	EXC_XFER_TEMPLATE(n, hdlr, n, COPY_EE, transfer_to_handler_full, \
+			  ret_from_except_full)
+
+#define EXC_XFER_EE_LITE(n, hdlr)	\
+	EXC_XFER_TEMPLATE(n, hdlr, n+1, COPY_EE, transfer_to_handler, \
+			  ret_from_except)
+
+/* System reset */
+/* core99 pmac starts the seconary here by changing the vector, and
+   putting it back to what it was (unknown_exception) when done.  */
+	EXCEPTION(0x100, Reset, unknown_exception, EXC_XFER_STD)
+
+/* Machine check */
+/*
+ * On CHRP, this is complicated by the fact that we could get a
+ * machine check inside RTAS, and we have no guarantee that certain
+ * critical registers will have the values we expect.  The set of
+ * registers that might have bad values includes all the GPRs
+ * and all the BATs.  We indicate that we are in RTAS by putting
+ * a non-zero value, the address of the exception frame to use,
+ * in SPRG2.  The machine check handler checks SPRG2 and uses its
+ * value if it is non-zero.  If we ever needed to free up SPRG2,
+ * we could use a field in the thread_info or thread_struct instead.
+ * (Other exception handlers assume that r1 is a valid kernel stack
+ * pointer when we take an exception from supervisor mode.)
+ *	-- paulus.
+ */
+	. = 0x200
+	DO_KVM  0x200
+	mtspr	SPRN_SPRG_SCRATCH0,r10
+	mtspr	SPRN_SPRG_SCRATCH1,r11
+	mfcr	r10
+#ifdef CONFIG_PPC_CHRP
+	mfspr	r11,SPRN_SPRG_RTAS
+	cmpwi	0,r11,0
+	bne	7f
+#endif /* CONFIG_PPC_CHRP */
+	EXCEPTION_PROLOG_1
+7:	EXCEPTION_PROLOG_2
+	addi	r3,r1,STACK_FRAME_OVERHEAD
+#ifdef CONFIG_PPC_CHRP
+	mfspr	r4,SPRN_SPRG_RTAS
+	cmpwi	cr1,r4,0
+	bne	cr1,1f
+#endif
+	EXC_XFER_STD(0x200, machine_check_exception)
+#ifdef CONFIG_PPC_CHRP
+1:	b	machine_check_in_rtas
+#endif
+
+/* Data access exception. */
+	. = 0x300
+	DO_KVM  0x300
+DataAccess:
+	EXCEPTION_PROLOG
+	mfspr	r10,SPRN_DSISR
+	stw	r10,_DSISR(r11)
+	andis.	r0,r10,(DSISR_BAD_FAULT_32S|DSISR_DABRMATCH)@h
+	bne	1f			/* if not, try to put a PTE */
+	mfspr	r4,SPRN_DAR		/* into the hash table */
+	rlwinm	r3,r10,32-15,21,21	/* DSISR_STORE -> _PAGE_RW */
+	bl	hash_page
+1:	lwz	r5,_DSISR(r11)		/* get DSISR value */
+	mfspr	r4,SPRN_DAR
+	EXC_XFER_LITE(0x300, handle_page_fault)
+
+
+/* Instruction access exception. */
+	. = 0x400
+	DO_KVM  0x400
+InstructionAccess:
+	EXCEPTION_PROLOG
+	andis.	r0,r9,SRR1_ISI_NOPT@h	/* no pte found? */
+	beq	1f			/* if so, try to put a PTE */
+	li	r3,0			/* into the hash table */
+	mr	r4,r12			/* SRR0 is fault address */
+	bl	hash_page
+1:	mr	r4,r12
+	andis.	r5,r9,DSISR_SRR1_MATCH_32S@h /* Filter relevant SRR1 bits */
+	EXC_XFER_LITE(0x400, handle_page_fault)
+
+/* External interrupt */
+	EXCEPTION(0x500, HardwareInterrupt, do_IRQ, EXC_XFER_LITE)
+
+/* Alignment exception */
+	. = 0x600
+	DO_KVM  0x600
+Alignment:
+	EXCEPTION_PROLOG
+	mfspr	r4,SPRN_DAR
+	stw	r4,_DAR(r11)
+	mfspr	r5,SPRN_DSISR
+	stw	r5,_DSISR(r11)
+	addi	r3,r1,STACK_FRAME_OVERHEAD
+	EXC_XFER_EE(0x600, alignment_exception)
+
+/* Program check exception */
+	EXCEPTION(0x700, ProgramCheck, program_check_exception, EXC_XFER_STD)
+
+/* Floating-point unavailable */
+	. = 0x800
+	DO_KVM  0x800
+FPUnavailable:
+BEGIN_FTR_SECTION
+/*
+ * Certain Freescale cores don't have a FPU and treat fp instructions
+ * as a FP Unavailable exception.  Redirect to illegal/emulation handling.
+ */
+	b 	ProgramCheck
+END_FTR_SECTION_IFSET(CPU_FTR_FPU_UNAVAILABLE)
+	EXCEPTION_PROLOG
+	beq	1f
+	bl	load_up_fpu		/* if from user, just load it up */
+	b	fast_exception_return
+1:	addi	r3,r1,STACK_FRAME_OVERHEAD
+	EXC_XFER_EE_LITE(0x800, kernel_fp_unavailable_exception)
+
+/* Decrementer */
+	EXCEPTION(0x900, Decrementer, timer_interrupt, EXC_XFER_LITE)
+
+	EXCEPTION(0xa00, Trap_0a, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0xb00, Trap_0b, unknown_exception, EXC_XFER_EE)
+
+/* System call */
+	. = 0xc00
+	DO_KVM  0xc00
+SystemCall:
+	EXCEPTION_PROLOG
+	EXC_XFER_EE_LITE(0xc00, DoSyscall)
+
+/* Single step - not used on 601 */
+	EXCEPTION(0xd00, SingleStep, single_step_exception, EXC_XFER_STD)
+	EXCEPTION(0xe00, Trap_0e, unknown_exception, EXC_XFER_EE)
+
+/*
+ * The Altivec unavailable trap is at 0x0f20.  Foo.
+ * We effectively remap it to 0x3000.
+ * We include an altivec unavailable exception vector even if
+ * not configured for Altivec, so that you can't panic a
+ * non-altivec kernel running on a machine with altivec just
+ * by executing an altivec instruction.
+ */
+	. = 0xf00
+	DO_KVM  0xf00
+	b	PerformanceMonitor
+
+	. = 0xf20
+	DO_KVM  0xf20
+	b	AltiVecUnavailable
+
+/*
+ * Handle TLB miss for instruction on 603/603e.
+ * Note: we get an alternate set of r0 - r3 to use automatically.
+ */
+	. = 0x1000
+InstructionTLBMiss:
+/*
+ * r0:	scratch
+ * r1:	linux style pte ( later becomes ppc hardware pte )
+ * r2:	ptr to linux-style pte
+ * r3:	scratch
+ */
+	/* Get PTE (linux-style) and check access */
+	mfspr	r3,SPRN_IMISS
+	lis	r1,PAGE_OFFSET@h		/* check if kernel address */
+	cmplw	0,r1,r3
+	mfspr	r2,SPRN_SPRG_THREAD
+	li	r1,_PAGE_USER|_PAGE_PRESENT /* low addresses tested as user */
+	lwz	r2,PGDIR(r2)
+	bge-	112f
+	mfspr	r2,SPRN_SRR1		/* and MSR_PR bit from SRR1 */
+	rlwimi	r1,r2,32-12,29,29	/* shift MSR_PR to _PAGE_USER posn */
+	lis	r2,swapper_pg_dir@ha	/* if kernel address, use */
+	addi	r2,r2,swapper_pg_dir@l	/* kernel page table */
+112:	tophys(r2,r2)
+	rlwimi	r2,r3,12,20,29		/* insert top 10 bits of address */
+	lwz	r2,0(r2)		/* get pmd entry */
+	rlwinm.	r2,r2,0,0,19		/* extract address of pte page */
+	beq-	InstructionAddressInvalid	/* return if no mapping */
+	rlwimi	r2,r3,22,20,29		/* insert next 10 bits of address */
+	lwz	r0,0(r2)		/* get linux-style pte */
+	andc.	r1,r1,r0		/* check access & ~permission */
+	bne-	InstructionAddressInvalid /* return if access not permitted */
+	ori	r0,r0,_PAGE_ACCESSED	/* set _PAGE_ACCESSED in pte */
+	/*
+	 * NOTE! We are assuming this is not an SMP system, otherwise
+	 * we would need to update the pte atomically with lwarx/stwcx.
+	 */
+	stw	r0,0(r2)		/* update PTE (accessed bit) */
+	/* Convert linux-style PTE to low word of PPC-style PTE */
+	rlwinm	r1,r0,32-10,31,31	/* _PAGE_RW -> PP lsb */
+	rlwinm	r2,r0,32-7,31,31	/* _PAGE_DIRTY -> PP lsb */
+	and	r1,r1,r2		/* writable if _RW and _DIRTY */
+	rlwimi	r0,r0,32-1,30,30	/* _PAGE_USER -> PP msb */
+	rlwimi	r0,r0,32-1,31,31	/* _PAGE_USER -> PP lsb */
+	ori	r1,r1,0xe04		/* clear out reserved bits */
+	andc	r1,r0,r1		/* PP = user? (rw&dirty? 2: 3): 0 */
+BEGIN_FTR_SECTION
+	rlwinm	r1,r1,0,~_PAGE_COHERENT	/* clear M (coherence not required) */
+END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
+	mtspr	SPRN_RPA,r1
+	tlbli	r3
+	mfspr	r3,SPRN_SRR1		/* Need to restore CR0 */
+	mtcrf	0x80,r3
+	rfi
+InstructionAddressInvalid:
+	mfspr	r3,SPRN_SRR1
+	rlwinm	r1,r3,9,6,6	/* Get load/store bit */
+
+	addis	r1,r1,0x2000
+	mtspr	SPRN_DSISR,r1	/* (shouldn't be needed) */
+	andi.	r2,r3,0xFFFF	/* Clear upper bits of SRR1 */
+	or	r2,r2,r1
+	mtspr	SPRN_SRR1,r2
+	mfspr	r1,SPRN_IMISS	/* Get failing address */
+	rlwinm.	r2,r2,0,31,31	/* Check for little endian access */
+	rlwimi	r2,r2,1,30,30	/* change 1 -> 3 */
+	xor	r1,r1,r2
+	mtspr	SPRN_DAR,r1	/* Set fault address */
+	mfmsr	r0		/* Restore "normal" registers */
+	xoris	r0,r0,MSR_TGPR>>16
+	mtcrf	0x80,r3		/* Restore CR0 */
+	mtmsr	r0
+	b	InstructionAccess
+
+/*
+ * Handle TLB miss for DATA Load operation on 603/603e
+ */
+	. = 0x1100
+DataLoadTLBMiss:
+/*
+ * r0:	scratch
+ * r1:	linux style pte ( later becomes ppc hardware pte )
+ * r2:	ptr to linux-style pte
+ * r3:	scratch
+ */
+	/* Get PTE (linux-style) and check access */
+	mfspr	r3,SPRN_DMISS
+	lis	r1,PAGE_OFFSET@h		/* check if kernel address */
+	cmplw	0,r1,r3
+	mfspr	r2,SPRN_SPRG_THREAD
+	li	r1,_PAGE_USER|_PAGE_PRESENT /* low addresses tested as user */
+	lwz	r2,PGDIR(r2)
+	bge-	112f
+	mfspr	r2,SPRN_SRR1		/* and MSR_PR bit from SRR1 */
+	rlwimi	r1,r2,32-12,29,29	/* shift MSR_PR to _PAGE_USER posn */
+	lis	r2,swapper_pg_dir@ha	/* if kernel address, use */
+	addi	r2,r2,swapper_pg_dir@l	/* kernel page table */
+112:	tophys(r2,r2)
+	rlwimi	r2,r3,12,20,29		/* insert top 10 bits of address */
+	lwz	r2,0(r2)		/* get pmd entry */
+	rlwinm.	r2,r2,0,0,19		/* extract address of pte page */
+	beq-	DataAddressInvalid	/* return if no mapping */
+	rlwimi	r2,r3,22,20,29		/* insert next 10 bits of address */
+	lwz	r0,0(r2)		/* get linux-style pte */
+	andc.	r1,r1,r0		/* check access & ~permission */
+	bne-	DataAddressInvalid	/* return if access not permitted */
+	ori	r0,r0,_PAGE_ACCESSED	/* set _PAGE_ACCESSED in pte */
+	/*
+	 * NOTE! We are assuming this is not an SMP system, otherwise
+	 * we would need to update the pte atomically with lwarx/stwcx.
+	 */
+	stw	r0,0(r2)		/* update PTE (accessed bit) */
+	/* Convert linux-style PTE to low word of PPC-style PTE */
+	rlwinm	r1,r0,32-10,31,31	/* _PAGE_RW -> PP lsb */
+	rlwinm	r2,r0,32-7,31,31	/* _PAGE_DIRTY -> PP lsb */
+	and	r1,r1,r2		/* writable if _RW and _DIRTY */
+	rlwimi	r0,r0,32-1,30,30	/* _PAGE_USER -> PP msb */
+	rlwimi	r0,r0,32-1,31,31	/* _PAGE_USER -> PP lsb */
+	ori	r1,r1,0xe04		/* clear out reserved bits */
+	andc	r1,r0,r1		/* PP = user? (rw&dirty? 2: 3): 0 */
+BEGIN_FTR_SECTION
+	rlwinm	r1,r1,0,~_PAGE_COHERENT	/* clear M (coherence not required) */
+END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
+	mtspr	SPRN_RPA,r1
+	mfspr	r2,SPRN_SRR1		/* Need to restore CR0 */
+	mtcrf	0x80,r2
+BEGIN_MMU_FTR_SECTION
+	li	r0,1
+	mfspr	r1,SPRN_SPRG_603_LRU
+	rlwinm	r2,r3,20,27,31		/* Get Address bits 15:19 */
+	slw	r0,r0,r2
+	xor	r1,r0,r1
+	srw	r0,r1,r2
+	mtspr   SPRN_SPRG_603_LRU,r1
+	mfspr	r2,SPRN_SRR1
+	rlwimi	r2,r0,31-14,14,14
+	mtspr   SPRN_SRR1,r2
+END_MMU_FTR_SECTION_IFSET(MMU_FTR_NEED_DTLB_SW_LRU)
+	tlbld	r3
+	rfi
+DataAddressInvalid:
+	mfspr	r3,SPRN_SRR1
+	rlwinm	r1,r3,9,6,6	/* Get load/store bit */
+	addis	r1,r1,0x2000
+	mtspr	SPRN_DSISR,r1
+	andi.	r2,r3,0xFFFF	/* Clear upper bits of SRR1 */
+	mtspr	SPRN_SRR1,r2
+	mfspr	r1,SPRN_DMISS	/* Get failing address */
+	rlwinm.	r2,r2,0,31,31	/* Check for little endian access */
+	beq	20f		/* Jump if big endian */
+	xori	r1,r1,3
+20:	mtspr	SPRN_DAR,r1	/* Set fault address */
+	mfmsr	r0		/* Restore "normal" registers */
+	xoris	r0,r0,MSR_TGPR>>16
+	mtcrf	0x80,r3		/* Restore CR0 */
+	mtmsr	r0
+	b	DataAccess
+
+/*
+ * Handle TLB miss for DATA Store on 603/603e
+ */
+	. = 0x1200
+DataStoreTLBMiss:
+/*
+ * r0:	scratch
+ * r1:	linux style pte ( later becomes ppc hardware pte )
+ * r2:	ptr to linux-style pte
+ * r3:	scratch
+ */
+	/* Get PTE (linux-style) and check access */
+	mfspr	r3,SPRN_DMISS
+	lis	r1,PAGE_OFFSET@h		/* check if kernel address */
+	cmplw	0,r1,r3
+	mfspr	r2,SPRN_SPRG_THREAD
+	li	r1,_PAGE_RW|_PAGE_USER|_PAGE_PRESENT /* access flags */
+	lwz	r2,PGDIR(r2)
+	bge-	112f
+	mfspr	r2,SPRN_SRR1		/* and MSR_PR bit from SRR1 */
+	rlwimi	r1,r2,32-12,29,29	/* shift MSR_PR to _PAGE_USER posn */
+	lis	r2,swapper_pg_dir@ha	/* if kernel address, use */
+	addi	r2,r2,swapper_pg_dir@l	/* kernel page table */
+112:	tophys(r2,r2)
+	rlwimi	r2,r3,12,20,29		/* insert top 10 bits of address */
+	lwz	r2,0(r2)		/* get pmd entry */
+	rlwinm.	r2,r2,0,0,19		/* extract address of pte page */
+	beq-	DataAddressInvalid	/* return if no mapping */
+	rlwimi	r2,r3,22,20,29		/* insert next 10 bits of address */
+	lwz	r0,0(r2)		/* get linux-style pte */
+	andc.	r1,r1,r0		/* check access & ~permission */
+	bne-	DataAddressInvalid	/* return if access not permitted */
+	ori	r0,r0,_PAGE_ACCESSED|_PAGE_DIRTY
+	/*
+	 * NOTE! We are assuming this is not an SMP system, otherwise
+	 * we would need to update the pte atomically with lwarx/stwcx.
+	 */
+	stw	r0,0(r2)		/* update PTE (accessed/dirty bits) */
+	/* Convert linux-style PTE to low word of PPC-style PTE */
+	rlwimi	r0,r0,32-1,30,30	/* _PAGE_USER -> PP msb */
+	li	r1,0xe05		/* clear out reserved bits & PP lsb */
+	andc	r1,r0,r1		/* PP = user? 2: 0 */
+BEGIN_FTR_SECTION
+	rlwinm	r1,r1,0,~_PAGE_COHERENT	/* clear M (coherence not required) */
+END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
+	mtspr	SPRN_RPA,r1
+	mfspr	r2,SPRN_SRR1		/* Need to restore CR0 */
+	mtcrf	0x80,r2
+BEGIN_MMU_FTR_SECTION
+	li	r0,1
+	mfspr	r1,SPRN_SPRG_603_LRU
+	rlwinm	r2,r3,20,27,31		/* Get Address bits 15:19 */
+	slw	r0,r0,r2
+	xor	r1,r0,r1
+	srw	r0,r1,r2
+	mtspr   SPRN_SPRG_603_LRU,r1
+	mfspr	r2,SPRN_SRR1
+	rlwimi	r2,r0,31-14,14,14
+	mtspr   SPRN_SRR1,r2
+END_MMU_FTR_SECTION_IFSET(MMU_FTR_NEED_DTLB_SW_LRU)
+	tlbld	r3
+	rfi
+
+#ifndef CONFIG_ALTIVEC
+#define altivec_assist_exception	unknown_exception
+#endif
+
+	EXCEPTION(0x1300, Trap_13, instruction_breakpoint_exception, EXC_XFER_EE)
+	EXCEPTION(0x1400, SMI, SMIException, EXC_XFER_EE)
+	EXCEPTION(0x1500, Trap_15, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x1600, Trap_16, altivec_assist_exception, EXC_XFER_EE)
+	EXCEPTION(0x1700, Trap_17, TAUException, EXC_XFER_STD)
+	EXCEPTION(0x1800, Trap_18, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x1900, Trap_19, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x1a00, Trap_1a, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x1b00, Trap_1b, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x1c00, Trap_1c, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x1d00, Trap_1d, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x1e00, Trap_1e, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x1f00, Trap_1f, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x2000, RunMode, RunModeException, EXC_XFER_EE)
+	EXCEPTION(0x2100, Trap_21, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x2200, Trap_22, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x2300, Trap_23, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x2400, Trap_24, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x2500, Trap_25, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x2600, Trap_26, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x2700, Trap_27, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x2800, Trap_28, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x2900, Trap_29, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x2a00, Trap_2a, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x2b00, Trap_2b, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x2c00, Trap_2c, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x2d00, Trap_2d, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x2e00, Trap_2e, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x2f00, Trap_2f, unknown_exception, EXC_XFER_EE)
+
+	. = 0x3000
+
+AltiVecUnavailable:
+	EXCEPTION_PROLOG
+#ifdef CONFIG_ALTIVEC
+	beq	1f
+	bl	load_up_altivec		/* if from user, just load it up */
+	b	fast_exception_return
+#endif /* CONFIG_ALTIVEC */
+1:	addi	r3,r1,STACK_FRAME_OVERHEAD
+	EXC_XFER_EE_LITE(0xf20, altivec_unavailable_exception)
+
+PerformanceMonitor:
+	EXCEPTION_PROLOG
+	addi	r3,r1,STACK_FRAME_OVERHEAD
+	EXC_XFER_STD(0xf00, performance_monitor_exception)
+
+
+/*
+ * This code is jumped to from the startup code to copy
+ * the kernel image to physical address PHYSICAL_START.
+ */
+relocate_kernel:
+	addis	r9,r26,klimit@ha	/* fetch klimit */
+	lwz	r25,klimit@l(r9)
+	addis	r25,r25,-KERNELBASE@h
+	lis	r3,PHYSICAL_START@h	/* Destination base address */
+	li	r6,0			/* Destination offset */
+	li	r5,0x4000		/* # bytes of memory to copy */
+	bl	copy_and_flush		/* copy the first 0x4000 bytes */
+	addi	r0,r3,4f@l		/* jump to the address of 4f */
+	mtctr	r0			/* in copy and do the rest. */
+	bctr				/* jump to the copy */
+4:	mr	r5,r25
+	bl	copy_and_flush		/* copy the rest */
+	b	turn_on_mmu
+
+/*
+ * 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.
+ */
+_ENTRY(copy_and_flush)
+	addi	r5,r5,-4
+	addi	r6,r6,-4
+4:	li	r0,L1_CACHE_BYTES/4
+	mtctr	r0
+3:	addi	r6,r6,4			/* copy a cache line */
+	lwzx	r0,r6,r4
+	stwx	r0,r6,r3
+	bdnz	3b
+	dcbst	r6,r3			/* write it to memory */
+	sync
+	icbi	r6,r3			/* flush the icache line */
+	cmplw	0,r6,r5
+	blt	4b
+	sync				/* additional sync needed on g4 */
+	isync
+	addi	r5,r5,4
+	addi	r6,r6,4
+	blr
+
+#ifdef CONFIG_SMP
+	.globl __secondary_start_mpc86xx
+__secondary_start_mpc86xx:
+	mfspr	r3, SPRN_PIR
+	stw	r3, __secondary_hold_acknowledge@l(0)
+	mr	r24, r3			/* cpu # */
+	b	__secondary_start
+
+	.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:
+	/* on powersurge, we come in here with IR=0 and DR=1, and DBAT 0
+	   set to map the 0xf0000000 - 0xffffffff region */
+	mfmsr	r0
+	rlwinm	r0,r0,0,28,26		/* clear DR (0x10) */
+	SYNC
+	mtmsr	r0
+	isync
+
+	.globl	__secondary_start
+__secondary_start:
+	/* Copy some CPU settings from CPU 0 */
+	bl	__restore_cpu_setup
+
+	lis	r3,-KERNELBASE@h
+	mr	r4,r24
+	bl	call_setup_cpu		/* Call setup_cpu for this CPU */
+#ifdef CONFIG_6xx
+	lis	r3,-KERNELBASE@h
+	bl	init_idle_6xx
+#endif /* CONFIG_6xx */
+
+	/* get current_thread_info and current */
+	lis	r1,secondary_ti@ha
+	tophys(r1,r1)
+	lwz	r1,secondary_ti@l(r1)
+	tophys(r2,r1)
+	lwz	r2,TI_TASK(r2)
+
+	/* stack */
+	addi	r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD
+	li	r0,0
+	tophys(r3,r1)
+	stw	r0,0(r3)
+
+	/* load up the MMU */
+	bl	load_up_mmu
+
+	/* ptr to phys current thread */
+	tophys(r4,r2)
+	addi	r4,r4,THREAD	/* phys address of our thread_struct */
+	mtspr	SPRN_SPRG_THREAD,r4
+	li	r3,0
+	mtspr	SPRN_SPRG_RTAS,r3	/* 0 => not in RTAS */
+
+	/* enable MMU and jump to start_secondary */
+	li	r4,MSR_KERNEL
+	lis	r3,start_secondary@h
+	ori	r3,r3,start_secondary@l
+	mtspr	SPRN_SRR0,r3
+	mtspr	SPRN_SRR1,r4
+	SYNC
+	RFI
+#endif /* CONFIG_SMP */
+
+#ifdef CONFIG_KVM_BOOK3S_HANDLER
+#include "../kvm/book3s_rmhandlers.S"
+#endif
+
+/*
+ * Those generic dummy functions are kept for CPUs not
+ * included in CONFIG_6xx
+ */
+#if !defined(CONFIG_6xx)
+_ENTRY(__save_cpu_setup)
+	blr
+_ENTRY(__restore_cpu_setup)
+	blr
+#endif /* !defined(CONFIG_6xx) */
+
+
+/*
+ * Load stuff into the MMU.  Intended to be called with
+ * IR=0 and DR=0.
+ */
+load_up_mmu:
+	sync			/* Force all PTE updates to finish */
+	isync
+	tlbia			/* Clear all TLB entries */
+	sync			/* wait for tlbia/tlbie to finish */
+	TLBSYNC			/* ... on all CPUs */
+	/* Load the SDR1 register (hash table base & size) */
+	lis	r6,_SDR1@ha
+	tophys(r6,r6)
+	lwz	r6,_SDR1@l(r6)
+	mtspr	SPRN_SDR1,r6
+	li	r0,16		/* load up segment register values */
+	mtctr	r0		/* for context 0 */
+	lis	r3,0x2000	/* Ku = 1, VSID = 0 */
+	li	r4,0
+3:	mtsrin	r3,r4
+	addi	r3,r3,0x111	/* increment VSID */
+	addis	r4,r4,0x1000	/* address of next segment */
+	bdnz	3b
+
+/* Load the BAT registers with the values set up by MMU_init.
+   MMU_init takes care of whether we're on a 601 or not. */
+	mfpvr	r3
+	srwi	r3,r3,16
+	cmpwi	r3,1
+	lis	r3,BATS@ha
+	addi	r3,r3,BATS@l
+	tophys(r3,r3)
+	LOAD_BAT(0,r3,r4,r5)
+	LOAD_BAT(1,r3,r4,r5)
+	LOAD_BAT(2,r3,r4,r5)
+	LOAD_BAT(3,r3,r4,r5)
+BEGIN_MMU_FTR_SECTION
+	LOAD_BAT(4,r3,r4,r5)
+	LOAD_BAT(5,r3,r4,r5)
+	LOAD_BAT(6,r3,r4,r5)
+	LOAD_BAT(7,r3,r4,r5)
+END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
+	blr
+
+/*
+ * This is where the main kernel code starts.
+ */
+start_here:
+	/* ptr to current */
+	lis	r2,init_task@h
+	ori	r2,r2,init_task@l
+	/* Set up for using our exception vectors */
+	/* ptr to phys current thread */
+	tophys(r4,r2)
+	addi	r4,r4,THREAD	/* init task's THREAD */
+	mtspr	SPRN_SPRG_THREAD,r4
+	li	r3,0
+	mtspr	SPRN_SPRG_RTAS,r3	/* 0 => not in RTAS */
+
+	/* stack */
+	lis	r1,init_thread_union@ha
+	addi	r1,r1,init_thread_union@l
+	li	r0,0
+	stwu	r0,THREAD_SIZE-STACK_FRAME_OVERHEAD(r1)
+/*
+ * Do early platform-specific initialization,
+ * and set up the MMU.
+ */
+	li	r3,0
+	mr	r4,r31
+	bl	machine_init
+	bl	__save_cpu_setup
+	bl	MMU_init
+
+/*
+ * Go back to running unmapped so we can load up new values
+ * for SDR1 (hash table pointer) and the segment registers
+ * and change to using our exception vectors.
+ */
+	lis	r4,2f@h
+	ori	r4,r4,2f@l
+	tophys(r4,r4)
+	li	r3,MSR_KERNEL & ~(MSR_IR|MSR_DR)
+	mtspr	SPRN_SRR0,r4
+	mtspr	SPRN_SRR1,r3
+	SYNC
+	RFI
+/* Load up the kernel context */
+2:	bl	load_up_mmu
+
+#ifdef CONFIG_BDI_SWITCH
+	/* Add helper information for the Abatron bdiGDB debugger.
+	 * We do this here because we know the mmu is disabled, and
+	 * will be enabled for real in just a few instructions.
+	 */
+	lis	r5, abatron_pteptrs@h
+	ori	r5, r5, abatron_pteptrs@l
+	stw	r5, 0xf0(r0)	/* This much match your Abatron config */
+	lis	r6, swapper_pg_dir@h
+	ori	r6, r6, swapper_pg_dir@l
+	tophys(r5, r5)
+	stw	r6, 0(r5)
+#endif /* CONFIG_BDI_SWITCH */
+
+/* Now turn on the MMU for real! */
+	li	r4,MSR_KERNEL
+	lis	r3,start_kernel@h
+	ori	r3,r3,start_kernel@l
+	mtspr	SPRN_SRR0,r3
+	mtspr	SPRN_SRR1,r4
+	SYNC
+	RFI
+
+/*
+ * void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next);
+ *
+ * Set up the segment registers for a new context.
+ */
+_ENTRY(switch_mmu_context)
+	lwz	r3,MMCONTEXTID(r4)
+	cmpwi	cr0,r3,0
+	blt-	4f
+	mulli	r3,r3,897	/* multiply context by skew factor */
+	rlwinm	r3,r3,4,8,27	/* VSID = (context & 0xfffff) << 4 */
+	addis	r3,r3,0x6000	/* Set Ks, Ku bits */
+	li	r0,NUM_USER_SEGMENTS
+	mtctr	r0
+
+#ifdef CONFIG_BDI_SWITCH
+	/* Context switch the PTE pointer for the Abatron BDI2000.
+	 * The PGDIR is passed as second argument.
+	 */
+	lwz	r4,MM_PGD(r4)
+	lis	r5, KERNELBASE@h
+	lwz	r5, 0xf0(r5)
+	stw	r4, 0x4(r5)
+#endif
+	li	r4,0
+	isync
+3:
+	mtsrin	r3,r4
+	addi	r3,r3,0x111	/* next VSID */
+	rlwinm	r3,r3,0,8,3	/* clear out any overflow from VSID field */
+	addis	r4,r4,0x1000	/* address of next segment */
+	bdnz	3b
+	sync
+	isync
+	blr
+4:	trap
+	EMIT_BUG_ENTRY 4b,__FILE__,__LINE__,0
+	blr
+EXPORT_SYMBOL(switch_mmu_context)
+
+/*
+ * An undocumented "feature" of 604e requires that the v bit
+ * be cleared before changing BAT values.
+ *
+ * Also, newer IBM firmware does not clear bat3 and 4 so
+ * this makes sure it's done.
+ *  -- Cort
+ */
+clear_bats:
+	li	r10,0
+	mfspr	r9,SPRN_PVR
+	rlwinm	r9,r9,16,16,31		/* r9 = 1 for 601, 4 for 604 */
+	cmpwi	r9, 1
+	beq	1f
+
+	mtspr	SPRN_DBAT0U,r10
+	mtspr	SPRN_DBAT0L,r10
+	mtspr	SPRN_DBAT1U,r10
+	mtspr	SPRN_DBAT1L,r10
+	mtspr	SPRN_DBAT2U,r10
+	mtspr	SPRN_DBAT2L,r10
+	mtspr	SPRN_DBAT3U,r10
+	mtspr	SPRN_DBAT3L,r10
+1:
+	mtspr	SPRN_IBAT0U,r10
+	mtspr	SPRN_IBAT0L,r10
+	mtspr	SPRN_IBAT1U,r10
+	mtspr	SPRN_IBAT1L,r10
+	mtspr	SPRN_IBAT2U,r10
+	mtspr	SPRN_IBAT2L,r10
+	mtspr	SPRN_IBAT3U,r10
+	mtspr	SPRN_IBAT3L,r10
+BEGIN_MMU_FTR_SECTION
+	/* Here's a tweak: at this point, CPU setup have
+	 * not been called yet, so HIGH_BAT_EN may not be
+	 * set in HID0 for the 745x processors. However, it
+	 * seems that doesn't affect our ability to actually
+	 * write to these SPRs.
+	 */
+	mtspr	SPRN_DBAT4U,r10
+	mtspr	SPRN_DBAT4L,r10
+	mtspr	SPRN_DBAT5U,r10
+	mtspr	SPRN_DBAT5L,r10
+	mtspr	SPRN_DBAT6U,r10
+	mtspr	SPRN_DBAT6L,r10
+	mtspr	SPRN_DBAT7U,r10
+	mtspr	SPRN_DBAT7L,r10
+	mtspr	SPRN_IBAT4U,r10
+	mtspr	SPRN_IBAT4L,r10
+	mtspr	SPRN_IBAT5U,r10
+	mtspr	SPRN_IBAT5L,r10
+	mtspr	SPRN_IBAT6U,r10
+	mtspr	SPRN_IBAT6L,r10
+	mtspr	SPRN_IBAT7U,r10
+	mtspr	SPRN_IBAT7L,r10
+END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
+	blr
+
+flush_tlbs:
+	lis	r10, 0x40
+1:	addic.	r10, r10, -0x1000
+	tlbie	r10
+	bgt	1b
+	sync
+	blr
+
+mmu_off:
+ 	addi	r4, r3, __after_mmu_off - _start
+	mfmsr	r3
+	andi.	r0,r3,MSR_DR|MSR_IR		/* MMU enabled? */
+	beqlr
+	andc	r3,r3,r0
+	mtspr	SPRN_SRR0,r4
+	mtspr	SPRN_SRR1,r3
+	sync
+	RFI
+
+/*
+ * On 601, we use 3 BATs to map up to 24M of RAM at _PAGE_OFFSET
+ * (we keep one for debugging) and on others, we use one 256M BAT.
+ */
+initial_bats:
+	lis	r11,PAGE_OFFSET@h
+	mfspr	r9,SPRN_PVR
+	rlwinm	r9,r9,16,16,31		/* r9 = 1 for 601, 4 for 604 */
+	cmpwi	0,r9,1
+	bne	4f
+	ori	r11,r11,4		/* set up BAT registers for 601 */
+	li	r8,0x7f			/* valid, block length = 8MB */
+	mtspr	SPRN_IBAT0U,r11		/* N.B. 601 has valid bit in */
+	mtspr	SPRN_IBAT0L,r8		/* lower BAT register */
+	addis	r11,r11,0x800000@h
+	addis	r8,r8,0x800000@h
+	mtspr	SPRN_IBAT1U,r11
+	mtspr	SPRN_IBAT1L,r8
+	addis	r11,r11,0x800000@h
+	addis	r8,r8,0x800000@h
+	mtspr	SPRN_IBAT2U,r11
+	mtspr	SPRN_IBAT2L,r8
+	isync
+	blr
+
+4:	tophys(r8,r11)
+#ifdef CONFIG_SMP
+	ori	r8,r8,0x12		/* R/W access, M=1 */
+#else
+	ori	r8,r8,2			/* R/W access */
+#endif /* CONFIG_SMP */
+	ori	r11,r11,BL_256M<<2|0x2	/* set up BAT registers for 604 */
+
+	mtspr	SPRN_DBAT0L,r8		/* N.B. 6xx (not 601) have valid */
+	mtspr	SPRN_DBAT0U,r11		/* bit in upper BAT register */
+	mtspr	SPRN_IBAT0L,r8
+	mtspr	SPRN_IBAT0U,r11
+	isync
+	blr
+
+
+#ifdef CONFIG_BOOTX_TEXT
+setup_disp_bat:
+	/*
+	 * setup the display bat prepared for us in prom.c
+	 */
+	mflr	r8
+	bl	reloc_offset
+	mtlr	r8
+	addis	r8,r3,disp_BAT@ha
+	addi	r8,r8,disp_BAT@l
+	cmpwi	cr0,r8,0
+	beqlr
+	lwz	r11,0(r8)
+	lwz	r8,4(r8)
+	mfspr	r9,SPRN_PVR
+	rlwinm	r9,r9,16,16,31		/* r9 = 1 for 601, 4 for 604 */
+	cmpwi	0,r9,1
+	beq	1f
+	mtspr	SPRN_DBAT3L,r8
+	mtspr	SPRN_DBAT3U,r11
+	blr
+1:	mtspr	SPRN_IBAT3L,r8
+	mtspr	SPRN_IBAT3U,r11
+	blr
+#endif /* CONFIG_BOOTX_TEXT */
+
+#ifdef CONFIG_PPC_EARLY_DEBUG_CPM
+setup_cpm_bat:
+	lis	r8, 0xf000
+	ori	r8, r8,	0x002a
+	mtspr	SPRN_DBAT1L, r8
+
+	lis	r11, 0xf000
+	ori	r11, r11, (BL_1M << 2) | 2
+	mtspr	SPRN_DBAT1U, r11
+
+	blr
+#endif
+
+#ifdef CONFIG_PPC_EARLY_DEBUG_USBGECKO
+setup_usbgecko_bat:
+	/* prepare a BAT for early io */
+#if defined(CONFIG_GAMECUBE)
+	lis	r8, 0x0c00
+#elif defined(CONFIG_WII)
+	lis	r8, 0x0d00
+#else
+#error Invalid platform for USB Gecko based early debugging.
+#endif
+	/*
+	 * The virtual address used must match the virtual address
+	 * associated to the fixmap entry FIX_EARLY_DEBUG_BASE.
+	 */
+	lis	r11, 0xfffe	/* top 128K */
+	ori	r8, r8, 0x002a	/* uncached, guarded ,rw */
+	ori	r11, r11, 0x2	/* 128K, Vs=1, Vp=0 */
+	mtspr	SPRN_DBAT1L, r8
+	mtspr	SPRN_DBAT1U, r11
+	blr
+#endif
+
+#ifdef CONFIG_8260
+/* Jump into the system reset for the rom.
+ * We first disable the MMU, and then jump to the ROM reset address.
+ *
+ * r3 is the board info structure, r4 is the location for starting.
+ * I use this for building a small kernel that can load other kernels,
+ * rather than trying to write or rely on a rom monitor that can tftp load.
+ */
+       .globl  m8260_gorom
+m8260_gorom:
+	mfmsr	r0
+	rlwinm	r0,r0,0,17,15	/* clear MSR_EE in r0 */
+	sync
+	mtmsr	r0
+	sync
+	mfspr	r11, SPRN_HID0
+	lis	r10, 0
+	ori	r10,r10,HID0_ICE|HID0_DCE
+	andc	r11, r11, r10
+	mtspr	SPRN_HID0, r11
+	isync
+	li	r5, MSR_ME|MSR_RI
+	lis	r6,2f@h
+	addis	r6,r6,-KERNELBASE@h
+	ori	r6,r6,2f@l
+	mtspr	SPRN_SRR0,r6
+	mtspr	SPRN_SRR1,r5
+	isync
+	sync
+	rfi
+2:
+	mtlr	r4
+	blr
+#endif
+
+
+/*
+ * We put a few things here that have to be page-aligned.
+ * This stuff goes at the beginning of the data segment,
+ * which is page-aligned.
+ */
+	.data
+	.globl	sdata
+sdata:
+	.globl	empty_zero_page
+empty_zero_page:
+	.space	4096
+EXPORT_SYMBOL(empty_zero_page)
+
+	.globl	swapper_pg_dir
+swapper_pg_dir:
+	.space	PGD_TABLE_SIZE
+
+/* Room for two PTE pointers, usually the kernel and current user pointers
+ * to their respective root page table.
+ */
+abatron_pteptrs:
+	.space	8