| /* |
| * 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); \ |
| 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 |