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Diffstat (limited to 'arch/powerpc/kernel/head_32.S')
| -rw-r--r-- | arch/powerpc/kernel/head_32.S | 1381 |
1 files changed, 1381 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S new file mode 100644 index 00000000000..b102e3a2415 --- /dev/null +++ b/arch/powerpc/kernel/head_32.S @@ -0,0 +1,1381 @@ +/* + * 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). + * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk). + * + * 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/config.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> + +#ifdef CONFIG_APUS +#include <asm/amigappc.h> +#endif + +/* 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: + + .text + .stabs "arch/powerpc/kernel/",N_SO,0,0,0f + .stabs "head_32.S",N_SO,0,0,0f +0: + .globl _stext +_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. + */ + .text + .globl _start +_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 + * + * APUS + * r3: 'APUS' + * r4: physical address of memory base + * Linux/m68k style BootInfo structure at &_end. + * + * 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 + bl prom_init + trap + +1: mr r31,r3 /* save parameters */ + mr r30,r4 + 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 + +#ifdef CONFIG_APUS +/* On APUS the __va/__pa constants need to be set to the correct + * values before continuing. + */ + mr r4,r30 + bl fix_mem_constants +#endif /* CONFIG_APUS */ + +/* 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 + +/* + * 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 */ + + +#ifndef CONFIG_APUS +/* + * 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 */ + cmpwi 0,r4,0 /* are we already running at 0? */ + bne relocate_kernel +#endif /* CONFIG_APUS */ +/* + * 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_SPRG0,r10; \ + mtspr SPRN_SPRG1,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_SPRG3; \ + 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 \ + CLR_TOP32(r11); \ + stw r10,_CCR(r11); /* save registers */ \ + stw r12,GPR12(r11); \ + stw r9,GPR9(r11); \ + mfspr r10,SPRN_SPRG0; \ + stw r10,GPR10(r11); \ + mfspr r12,SPRN_SPRG1; \ + 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 r10,0x7265; /* put exception frame marker */ \ + addi r10,r10,0x6773; \ + 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; \ +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. */ +#if defined(CONFIG_GEMINI) && defined(CONFIG_SMP) + . = 0x100 + b __secondary_start_gemini +#else + EXCEPTION(0x100, Reset, unknown_exception, EXC_XFER_STD) +#endif + +/* 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 + mtspr SPRN_SPRG0,r10 + mtspr SPRN_SPRG1,r11 + mfcr r10 +#ifdef CONFIG_PPC_CHRP + mfspr r11,SPRN_SPRG2 + 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_SPRG2 + 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 +DataAccess: + EXCEPTION_PROLOG + mfspr r10,SPRN_DSISR + andis. r0,r10,0xa470 /* weird error? */ + 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: stw r10,_DSISR(r11) + mr r5,r10 + mfspr r4,SPRN_DAR + EXC_XFER_EE_LITE(0x300, handle_page_fault) + + +/* Instruction access exception. */ + . = 0x400 +InstructionAccess: + EXCEPTION_PROLOG + andis. r0,r9,0x4000 /* 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 + mr r5,r9 + EXC_XFER_EE_LITE(0x400, handle_page_fault) + +/* External interrupt */ + EXCEPTION(0x500, HardwareInterrupt, do_IRQ, EXC_XFER_LITE) + +/* Alignment exception */ + . = 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 +FPUnavailable: + EXCEPTION_PROLOG + bne load_up_fpu /* if from user, just load it up */ + 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 +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 + b Trap_0f + + . = 0xf20 + b AltiVecUnavailable + +Trap_0f: + EXCEPTION_PROLOG + addi r3,r1,STACK_FRAME_OVERHEAD + EXC_XFER_EE(0xf00, unknown_exception) + +/* + * Handle TLB miss for instruction on 603/603e. + * Note: we get an alternate set of r0 - r3 to use automatically. + */ + . = 0x1000 +InstructionTLBMiss: +/* + * r0: stored ctr + * r1: linux style pte ( later becomes ppc hardware pte ) + * r2: ptr to linux-style pte + * r3: scratch + */ + mfctr r0 + /* Get PTE (linux-style) and check access */ + mfspr r3,SPRN_IMISS + lis r1,KERNELBASE@h /* check if kernel address */ + cmplw 0,r3,r1 + mfspr r2,SPRN_SPRG3 + li r1,_PAGE_USER|_PAGE_PRESENT /* low addresses tested as user */ + lwz r2,PGDIR(r2) + blt+ 112f + lis r2,swapper_pg_dir@ha /* if kernel address, use */ + addi r2,r2,swapper_pg_dir@l /* kernel page table */ + mfspr r1,SPRN_SRR1 /* and MSR_PR bit from SRR1 */ + rlwinm r1,r1,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */ +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 r3,0(r2) /* get linux-style pte */ + andc. r1,r1,r3 /* check access & ~permission */ + bne- InstructionAddressInvalid /* return if access not permitted */ + ori r3,r3,_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 r3,0(r2) /* update PTE (accessed bit) */ + /* Convert linux-style PTE to low word of PPC-style PTE */ + rlwinm r1,r3,32-10,31,31 /* _PAGE_RW -> PP lsb */ + rlwinm r2,r3,32-7,31,31 /* _PAGE_DIRTY -> PP lsb */ + and r1,r1,r2 /* writable if _RW and _DIRTY */ + rlwimi r3,r3,32-1,30,30 /* _PAGE_USER -> PP msb */ + rlwimi r3,r3,32-1,31,31 /* _PAGE_USER -> PP lsb */ + ori r1,r1,0xe14 /* clear out reserved bits and M */ + andc r1,r3,r1 /* PP = user? (rw&dirty? 2: 3): 0 */ + mtspr SPRN_RPA,r1 + mfspr r3,SPRN_IMISS + 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) */ + mtctr r0 /* Restore CTR */ + 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: stored ctr + * r1: linux style pte ( later becomes ppc hardware pte ) + * r2: ptr to linux-style pte + * r3: scratch + */ + mfctr r0 + /* Get PTE (linux-style) and check access */ + mfspr r3,SPRN_DMISS + lis r1,KERNELBASE@h /* check if kernel address */ + cmplw 0,r3,r1 + mfspr r2,SPRN_SPRG3 + li r1,_PAGE_USER|_PAGE_PRESENT /* low addresses tested as user */ + lwz r2,PGDIR(r2) + blt+ 112f + lis r2,swapper_pg_dir@ha /* if kernel address, use */ + addi r2,r2,swapper_pg_dir@l /* kernel page table */ + mfspr r1,SPRN_SRR1 /* and MSR_PR bit from SRR1 */ + rlwinm r1,r1,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */ +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 r3,0(r2) /* get linux-style pte */ + andc. r1,r1,r3 /* check access & ~permission */ + bne- DataAddressInvalid /* return if access not permitted */ + ori r3,r3,_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 r3,0(r2) /* update PTE (accessed bit) */ + /* Convert linux-style PTE to low word of PPC-style PTE */ + rlwinm r1,r3,32-10,31,31 /* _PAGE_RW -> PP lsb */ + rlwinm r2,r3,32-7,31,31 /* _PAGE_DIRTY -> PP lsb */ + and r1,r1,r2 /* writable if _RW and _DIRTY */ + rlwimi r3,r3,32-1,30,30 /* _PAGE_USER -> PP msb */ + rlwimi r3,r3,32-1,31,31 /* _PAGE_USER -> PP lsb */ + ori r1,r1,0xe14 /* clear out reserved bits and M */ + andc r1,r3,r1 /* PP = user? (rw&dirty? 2: 3): 0 */ + mtspr SPRN_RPA,r1 + mfspr r3,SPRN_DMISS + tlbld r3 + mfspr r3,SPRN_SRR1 /* Need to restore CR0 */ + mtcrf 0x80,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 + mtctr r0 /* Restore CTR */ + 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: stored ctr + * r1: linux style pte ( later becomes ppc hardware pte ) + * r2: ptr to linux-style pte + * r3: scratch + */ + mfctr r0 + /* Get PTE (linux-style) and check access */ + mfspr r3,SPRN_DMISS + lis r1,KERNELBASE@h /* check if kernel address */ + cmplw 0,r3,r1 + mfspr r2,SPRN_SPRG3 + li r1,_PAGE_RW|_PAGE_USER|_PAGE_PRESENT /* access flags */ + lwz r2,PGDIR(r2) + blt+ 112f + lis r2,swapper_pg_dir@ha /* if kernel address, use */ + addi r2,r2,swapper_pg_dir@l /* kernel page table */ + mfspr r1,SPRN_SRR1 /* and MSR_PR bit from SRR1 */ + rlwinm r1,r1,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */ +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 r3,0(r2) /* get linux-style pte */ + andc. r1,r1,r3 /* check access & ~permission */ + bne- DataAddressInvalid /* return if access not permitted */ + ori r3,r3,_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 r3,0(r2) /* update PTE (accessed/dirty bits) */ + /* Convert linux-style PTE to low word of PPC-style PTE */ + rlwimi r3,r3,32-1,30,30 /* _PAGE_USER -> PP msb */ + li r1,0xe15 /* clear out reserved bits and M */ + andc r1,r3,r1 /* PP = user? 2: 0 */ + mtspr SPRN_RPA,r1 + mfspr r3,SPRN_DMISS + tlbld r3 + mfspr r3,SPRN_SRR1 /* Need to restore CR0 */ + mtcrf 0x80,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, MOLTrampoline, unknown_exception, EXC_XFER_EE_LITE) + + .globl mol_trampoline + .set mol_trampoline, i0x2f00 + + . = 0x3000 + +AltiVecUnavailable: + EXCEPTION_PROLOG +#ifdef CONFIG_ALTIVEC + bne load_up_altivec /* if from user, just load it up */ +#endif /* CONFIG_ALTIVEC */ + EXC_XFER_EE_LITE(0xf20, altivec_unavailable_exception) + +#ifdef CONFIG_ALTIVEC +/* Note that the AltiVec support is closely modeled after the FP + * support. Changes to one are likely to be applicable to the + * other! */ +load_up_altivec: +/* + * Disable AltiVec for the task which had AltiVec previously, + * and save its AltiVec registers in its thread_struct. + * Enables AltiVec for use in the kernel on return. + * On SMP we know the AltiVec units are free, since we give it up every + * switch. -- Kumar + */ + mfmsr r5 + oris r5,r5,MSR_VEC@h + MTMSRD(r5) /* enable use of AltiVec now */ + isync +/* + * For SMP, we don't do lazy AltiVec switching because it just gets too + * horrendously complex, especially when a task switches from one CPU + * to another. Instead we call giveup_altivec in switch_to. + */ +#ifndef CONFIG_SMP + tophys(r6,0) + addis r3,r6,last_task_used_altivec@ha + lwz r4,last_task_used_altivec@l(r3) + cmpwi 0,r4,0 + beq 1f + add r4,r4,r6 + addi r4,r4,THREAD /* want THREAD of last_task_used_altivec */ + SAVE_32VRS(0,r10,r4) + mfvscr vr0 + li r10,THREAD_VSCR + stvx vr0,r10,r4 + lwz r5,PT_REGS(r4) + add r5,r5,r6 + lwz r4,_MSR-STACK_FRAME_OVERHEAD(r5) + lis r10,MSR_VEC@h + andc r4,r4,r10 /* disable altivec for previous task */ + stw r4,_MSR-STACK_FRAME_OVERHEAD(r5) +1: +#endif /* CONFIG_SMP */ + /* enable use of AltiVec after return */ + oris r9,r9,MSR_VEC@h + mfspr r5,SPRN_SPRG3 /* current task's THREAD (phys) */ + li r4,1 + li r10,THREAD_VSCR + stw r4,THREAD_USED_VR(r5) + lvx vr0,r10,r5 + mtvscr vr0 + REST_32VRS(0,r10,r5) +#ifndef CONFIG_SMP + subi r4,r5,THREAD + sub r4,r4,r6 + stw r4,last_task_used_altivec@l(r3) +#endif /* CONFIG_SMP */ + /* restore registers and return */ + /* we haven't used ctr or xer or lr */ + b fast_exception_return + +/* + * AltiVec unavailable trap from kernel - print a message, but let + * the task use AltiVec in the kernel until it returns to user mode. + */ +KernelAltiVec: + lwz r3,_MSR(r1) + oris r3,r3,MSR_VEC@h + stw r3,_MSR(r1) /* enable use of AltiVec after return */ + lis r3,87f@h + ori r3,r3,87f@l + mr r4,r2 /* current */ + lwz r5,_NIP(r1) + bl printk + b ret_from_except +87: .string "AltiVec used in kernel (task=%p, pc=%x) \n" + .align 4,0 + +/* + * giveup_altivec(tsk) + * Disable AltiVec for the task given as the argument, + * and save the AltiVec registers in its thread_struct. + * Enables AltiVec for use in the kernel on return. + */ + + .globl giveup_altivec +giveup_altivec: + mfmsr r5 + oris r5,r5,MSR_VEC@h + SYNC + MTMSRD(r5) /* enable use of AltiVec now */ + isync + cmpwi 0,r3,0 + beqlr- /* if no previous owner, done */ + addi r3,r3,THREAD /* want THREAD of task */ + lwz r5,PT_REGS(r3) + cmpwi 0,r5,0 + SAVE_32VRS(0, r4, r3) + mfvscr vr0 + li r4,THREAD_VSCR + stvx vr0,r4,r3 + beq 1f + lwz r4,_MSR-STACK_FRAME_OVERHEAD(r5) + lis r3,MSR_VEC@h + andc r4,r4,r3 /* disable AltiVec for previous task */ + stw r4,_MSR-STACK_FRAME_OVERHEAD(r5) +1: +#ifndef CONFIG_SMP + li r5,0 + lis r4,last_task_used_altivec@ha + stw r5,last_task_used_altivec@l(r4) +#endif /* CONFIG_SMP */ + blr +#endif /* CONFIG_ALTIVEC */ + +/* + * This code is jumped to from the startup code to copy + * the kernel image to physical address 0. + */ +relocate_kernel: + addis r9,r26,klimit@ha /* fetch klimit */ + lwz r25,klimit@l(r9) + addis r25,r25,-KERNELBASE@h + li r3,0 /* 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. + */ +_GLOBAL(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_APUS +/* + * On APUS the physical base address of the kernel is not known at compile + * time, which means the __pa/__va constants used are incorrect. In the + * __init section is recorded the virtual addresses of instructions using + * these constants, so all that has to be done is fix these before + * continuing the kernel boot. + * + * r4 = The physical address of the kernel base. + */ +fix_mem_constants: + mr r10,r4 + addis r10,r10,-KERNELBASE@h /* virt_to_phys constant */ + neg r11,r10 /* phys_to_virt constant */ + + lis r12,__vtop_table_begin@h + ori r12,r12,__vtop_table_begin@l + add r12,r12,r10 /* table begin phys address */ + lis r13,__vtop_table_end@h + ori r13,r13,__vtop_table_end@l + add r13,r13,r10 /* table end phys address */ + subi r12,r12,4 + subi r13,r13,4 +1: lwzu r14,4(r12) /* virt address of instruction */ + add r14,r14,r10 /* phys address of instruction */ + lwz r15,0(r14) /* instruction, now insert top */ + rlwimi r15,r10,16,16,31 /* half of vp const in low half */ + stw r15,0(r14) /* of instruction and restore. */ + dcbst r0,r14 /* write it to memory */ + sync + icbi r0,r14 /* flush the icache line */ + cmpw r12,r13 + bne 1b + sync /* additional sync needed on g4 */ + isync + +/* + * Map the memory where the exception handlers will + * be copied to when hash constants have been patched. + */ +#ifdef CONFIG_APUS_FAST_EXCEPT + lis r8,0xfff0 +#else + lis r8,0 +#endif + ori r8,r8,0x2 /* 128KB, supervisor */ + mtspr SPRN_DBAT3U,r8 + mtspr SPRN_DBAT3L,r8 + + lis r12,__ptov_table_begin@h + ori r12,r12,__ptov_table_begin@l + add r12,r12,r10 /* table begin phys address */ + lis r13,__ptov_table_end@h + ori r13,r13,__ptov_table_end@l + add r13,r13,r10 /* table end phys address */ + subi r12,r12,4 + subi r13,r13,4 +1: lwzu r14,4(r12) /* virt address of instruction */ + add r14,r14,r10 /* phys address of instruction */ + lwz r15,0(r14) /* instruction, now insert top */ + rlwimi r15,r11,16,16,31 /* half of pv const in low half*/ + stw r15,0(r14) /* of instruction and restore. */ + dcbst r0,r14 /* write it to memory */ + sync + icbi r0,r14 /* flush the icache line */ + cmpw r12,r13 + bne 1b + + sync /* additional sync needed on g4 */ + isync /* No speculative loading until now */ + blr + +/*********************************************************************** + * Please note that on APUS the exception handlers are located at the + * physical address 0xfff0000. For this reason, the exception handlers + * cannot use relative branches to access the code below. + ***********************************************************************/ +#endif /* CONFIG_APUS */ + +#ifdef CONFIG_SMP +#ifdef CONFIG_GEMINI + .globl __secondary_start_gemini +__secondary_start_gemini: + mfspr r4,SPRN_HID0 + ori r4,r4,HID0_ICFI + li r3,0 + ori r3,r3,HID0_ICE + andc r4,r4,r3 + mtspr SPRN_HID0,r4 + sync + b __secondary_start +#endif /* CONFIG_GEMINI */ + + .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 */ + CLR_TOP32(r4) + mtspr SPRN_SPRG3,r4 + li r3,0 + mtspr SPRN_SPRG2,r3 /* 0 => not in RTAS */ + + /* enable MMU and jump to start_secondary */ + li r4,MSR_KERNEL + FIX_SRR1(r4,r5) + lis r3,start_secondary@h + ori r3,r3,start_secondary@l + mtspr SPRN_SRR0,r3 + mtspr SPRN_SRR1,r4 + SYNC + RFI +#endif /* CONFIG_SMP */ + +/* + * Those generic dummy functions are kept for CPUs not + * included in CONFIG_6xx + */ +#if !defined(CONFIG_6xx) +_GLOBAL(__save_cpu_setup) + blr +_GLOBAL(__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) + + 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 */ + CLR_TOP32(r4) + mtspr SPRN_SPRG3,r4 + li r3,0 + mtspr SPRN_SPRG2,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. + */ + mr r3,r31 + mr r4,r30 + bl machine_init + bl MMU_init + +#ifdef CONFIG_APUS + /* Copy exception code to exception vector base on APUS. */ + lis r4,KERNELBASE@h +#ifdef CONFIG_APUS_FAST_EXCEPT + lis r3,0xfff0 /* Copy to 0xfff00000 */ +#else + lis r3,0 /* Copy to 0x00000000 */ +#endif + li r5,0x4000 /* # bytes of memory to copy */ + li r6,0 + bl copy_and_flush /* copy the first 0x4000 bytes */ +#endif /* CONFIG_APUS */ + +/* + * 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) + FIX_SRR1(r3,r5) + 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 + FIX_SRR1(r4,r5) + lis r3,start_kernel@h + ori r3,r3,start_kernel@l + mtspr SPRN_SRR0,r3 + mtspr SPRN_SRR1,r4 + SYNC + RFI + +/* + * Set up the segment registers for a new context. + */ +_GLOBAL(set_context) + 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. + */ + 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 + +/* + * 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_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_FTR_SECTION_IFSET(CPU_FTR_HAS_HIGH_BATS) + blr + +flush_tlbs: + lis r10, 0x40 +1: addic. r10, r10, -0x1000 + tlbie r10 + blt 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 + +/* + * Use the first pair of BAT registers to map the 1st 16MB + * of RAM to KERNELBASE. From this point on we can't safely + * call OF any more. + */ +initial_bats: + lis r11,KERNELBASE@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 */ + oris r9,r11,0x800000@h /* set up BAT reg for 2nd 8M */ + oris r10,r8,0x800000@h /* set up BAT reg for 2nd 8M */ + mtspr SPRN_IBAT0U,r11 /* N.B. 601 has valid bit in */ + mtspr SPRN_IBAT0L,r8 /* lower BAT register */ + mtspr SPRN_IBAT1U,r9 + mtspr SPRN_IBAT1L,r10 + 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 */ +#ifdef CONFIG_APUS + ori r11,r11,BL_8M<<2|0x2 /* set up 8MB BAT registers for 604 */ +#else + ori r11,r11,BL_256M<<2|0x2 /* set up BAT registers for 604 */ +#endif /* CONFIG_APUS */ + + 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_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 + + .globl swapper_pg_dir +swapper_pg_dir: + .space 4096 + +/* + * This space gets a copy of optional info passed to us by the bootstrap + * Used to pass parameters into the kernel like root=/dev/sda1, etc. + */ + .globl cmd_line +cmd_line: + .space 512 + + .globl intercept_table +intercept_table: + .long 0, 0, i0x200, i0x300, i0x400, 0, i0x600, i0x700 + .long i0x800, 0, 0, 0, 0, i0xd00, 0, 0 + .long 0, 0, 0, i0x1300, 0, 0, 0, 0 + .long 0, 0, 0, 0, 0, 0, 0, 0 + .long 0, 0, 0, 0, 0, 0, 0, 0 + .long 0, 0, 0, 0, 0, 0, 0, 0 + +/* Room for two PTE pointers, usually the kernel and current user pointers + * to their respective root page table. + */ +abatron_pteptrs: + .space 8 |