diff options
Diffstat (limited to 'arch/powerpc/kernel/head_fsl_booke.S')
| -rw-r--r-- | arch/powerpc/kernel/head_fsl_booke.S | 1058 |
1 files changed, 1058 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S new file mode 100644 index 00000000000..eba5a5f8ff0 --- /dev/null +++ b/arch/powerpc/kernel/head_fsl_booke.S @@ -0,0 +1,1058 @@ +/* + * arch/ppc/kernel/head_fsl_booke.S + * + * Kernel execution entry point code. + * + * Copyright (c) 1995-1996 Gary Thomas <gdt@linuxppc.org> + * Initial PowerPC version. + * Copyright (c) 1996 Cort Dougan <cort@cs.nmt.edu> + * Rewritten for PReP + * Copyright (c) 1996 Paul Mackerras <paulus@cs.anu.edu.au> + * Low-level exception handers, MMU support, and rewrite. + * Copyright (c) 1997 Dan Malek <dmalek@jlc.net> + * PowerPC 8xx modifications. + * Copyright (c) 1998-1999 TiVo, Inc. + * PowerPC 403GCX modifications. + * Copyright (c) 1999 Grant Erickson <grant@lcse.umn.edu> + * PowerPC 403GCX/405GP modifications. + * Copyright 2000 MontaVista Software Inc. + * PPC405 modifications + * PowerPC 403GCX/405GP modifications. + * Author: MontaVista Software, Inc. + * frank_rowand@mvista.com or source@mvista.com + * debbie_chu@mvista.com + * Copyright 2002-2004 MontaVista Software, Inc. + * PowerPC 44x support, Matt Porter <mporter@kernel.crashing.org> + * Copyright 2004 Freescale Semiconductor, Inc + * PowerPC e500 modifications, Kumar Gala <kumar.gala@freescale.com> + * + * 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 <linux/threads.h> +#include <asm/processor.h> +#include <asm/page.h> +#include <asm/mmu.h> +#include <asm/pgtable.h> +#include <asm/cputable.h> +#include <asm/thread_info.h> +#include <asm/ppc_asm.h> +#include <asm/asm-offsets.h> +#include "head_booke.h" + +/* As with the other PowerPC ports, it is expected that when code + * execution begins here, the following registers contain valid, yet + * optional, information: + * + * r3 - Board info structure pointer (DRAM, frequency, MAC address, etc.) + * r4 - Starting address of the init RAM disk + * r5 - Ending address of the init RAM disk + * r6 - Start of kernel command line string (e.g. "mem=128") + * r7 - End of kernel command line string + * + */ + .text +_GLOBAL(_stext) +_GLOBAL(_start) + /* + * Reserve a word at a fixed location to store the address + * of abatron_pteptrs + */ + nop +/* + * Save parameters we are passed + */ + mr r31,r3 + mr r30,r4 + mr r29,r5 + mr r28,r6 + mr r27,r7 + li r24,0 /* CPU number */ + +/* We try to not make any assumptions about how the boot loader + * setup or used the TLBs. We invalidate all mappings from the + * boot loader and load a single entry in TLB1[0] to map the + * first 16M of kernel memory. Any boot info passed from the + * bootloader needs to live in this first 16M. + * + * Requirement on bootloader: + * - The page we're executing in needs to reside in TLB1 and + * have IPROT=1. If not an invalidate broadcast could + * evict the entry we're currently executing in. + * + * r3 = Index of TLB1 were executing in + * r4 = Current MSR[IS] + * r5 = Index of TLB1 temp mapping + * + * Later in mapin_ram we will correctly map lowmem, and resize TLB1[0] + * if needed + */ + +/* 1. Find the index of the entry we're executing in */ + bl invstr /* Find our address */ +invstr: mflr r6 /* Make it accessible */ + mfmsr r7 + rlwinm r4,r7,27,31,31 /* extract MSR[IS] */ + mfspr r7, SPRN_PID0 + slwi r7,r7,16 + or r7,r7,r4 + mtspr SPRN_MAS6,r7 + tlbsx 0,r6 /* search MSR[IS], SPID=PID0 */ +#ifndef CONFIG_E200 + mfspr r7,SPRN_MAS1 + andis. r7,r7,MAS1_VALID@h + bne match_TLB + mfspr r7,SPRN_PID1 + slwi r7,r7,16 + or r7,r7,r4 + mtspr SPRN_MAS6,r7 + tlbsx 0,r6 /* search MSR[IS], SPID=PID1 */ + mfspr r7,SPRN_MAS1 + andis. r7,r7,MAS1_VALID@h + bne match_TLB + mfspr r7, SPRN_PID2 + slwi r7,r7,16 + or r7,r7,r4 + mtspr SPRN_MAS6,r7 + tlbsx 0,r6 /* Fall through, we had to match */ +#endif +match_TLB: + mfspr r7,SPRN_MAS0 + rlwinm r3,r7,16,20,31 /* Extract MAS0(Entry) */ + + mfspr r7,SPRN_MAS1 /* Insure IPROT set */ + oris r7,r7,MAS1_IPROT@h + mtspr SPRN_MAS1,r7 + tlbwe + +/* 2. Invalidate all entries except the entry we're executing in */ + mfspr r9,SPRN_TLB1CFG + andi. r9,r9,0xfff + li r6,0 /* Set Entry counter to 0 */ +1: lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */ + rlwimi r7,r6,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r6) */ + mtspr SPRN_MAS0,r7 + tlbre + mfspr r7,SPRN_MAS1 + rlwinm r7,r7,0,2,31 /* Clear MAS1 Valid and IPROT */ + cmpw r3,r6 + beq skpinv /* Dont update the current execution TLB */ + mtspr SPRN_MAS1,r7 + tlbwe + isync +skpinv: addi r6,r6,1 /* Increment */ + cmpw r6,r9 /* Are we done? */ + bne 1b /* If not, repeat */ + + /* Invalidate TLB0 */ + li r6,0x04 + tlbivax 0,r6 +#ifdef CONFIG_SMP + tlbsync +#endif + /* Invalidate TLB1 */ + li r6,0x0c + tlbivax 0,r6 +#ifdef CONFIG_SMP + tlbsync +#endif + msync + +/* 3. Setup a temp mapping and jump to it */ + andi. r5, r3, 0x1 /* Find an entry not used and is non-zero */ + addi r5, r5, 0x1 + lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */ + rlwimi r7,r3,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r3) */ + mtspr SPRN_MAS0,r7 + tlbre + + /* Just modify the entry ID and EPN for the temp mapping */ + lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */ + rlwimi r7,r5,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r5) */ + mtspr SPRN_MAS0,r7 + xori r6,r4,1 /* Setup TMP mapping in the other Address space */ + slwi r6,r6,12 + oris r6,r6,(MAS1_VALID|MAS1_IPROT)@h + ori r6,r6,(MAS1_TSIZE(BOOKE_PAGESZ_4K))@l + mtspr SPRN_MAS1,r6 + mfspr r6,SPRN_MAS2 + li r7,0 /* temp EPN = 0 */ + rlwimi r7,r6,0,20,31 + mtspr SPRN_MAS2,r7 + tlbwe + + xori r6,r4,1 + slwi r6,r6,5 /* setup new context with other address space */ + bl 1f /* Find our address */ +1: mflr r9 + rlwimi r7,r9,0,20,31 + addi r7,r7,24 + mtspr SPRN_SRR0,r7 + mtspr SPRN_SRR1,r6 + rfi + +/* 4. Clear out PIDs & Search info */ + li r6,0 + mtspr SPRN_PID0,r6 +#ifndef CONFIG_E200 + mtspr SPRN_PID1,r6 + mtspr SPRN_PID2,r6 +#endif + mtspr SPRN_MAS6,r6 + +/* 5. Invalidate mapping we started in */ + lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */ + rlwimi r7,r3,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r3) */ + mtspr SPRN_MAS0,r7 + tlbre + li r6,0 + mtspr SPRN_MAS1,r6 + tlbwe + /* Invalidate TLB1 */ + li r9,0x0c + tlbivax 0,r9 +#ifdef CONFIG_SMP + tlbsync +#endif + msync + +/* 6. Setup KERNELBASE mapping in TLB1[0] */ + lis r6,0x1000 /* Set MAS0(TLBSEL) = TLB1(1), ESEL = 0 */ + mtspr SPRN_MAS0,r6 + lis r6,(MAS1_VALID|MAS1_IPROT)@h + ori r6,r6,(MAS1_TSIZE(BOOKE_PAGESZ_16M))@l + mtspr SPRN_MAS1,r6 + li r7,0 + lis r6,KERNELBASE@h + ori r6,r6,KERNELBASE@l + rlwimi r6,r7,0,20,31 + mtspr SPRN_MAS2,r6 + li r7,(MAS3_SX|MAS3_SW|MAS3_SR) + mtspr SPRN_MAS3,r7 + tlbwe + +/* 7. Jump to KERNELBASE mapping */ + lis r7,MSR_KERNEL@h + ori r7,r7,MSR_KERNEL@l + bl 1f /* Find our address */ +1: mflr r9 + rlwimi r6,r9,0,20,31 + addi r6,r6,24 + mtspr SPRN_SRR0,r6 + mtspr SPRN_SRR1,r7 + rfi /* start execution out of TLB1[0] entry */ + +/* 8. Clear out the temp mapping */ + lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */ + rlwimi r7,r5,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r5) */ + mtspr SPRN_MAS0,r7 + tlbre + mtspr SPRN_MAS1,r8 + tlbwe + /* Invalidate TLB1 */ + li r9,0x0c + tlbivax 0,r9 +#ifdef CONFIG_SMP + tlbsync +#endif + msync + + /* Establish the interrupt vector offsets */ + SET_IVOR(0, CriticalInput); + SET_IVOR(1, MachineCheck); + SET_IVOR(2, DataStorage); + SET_IVOR(3, InstructionStorage); + SET_IVOR(4, ExternalInput); + SET_IVOR(5, Alignment); + SET_IVOR(6, Program); + SET_IVOR(7, FloatingPointUnavailable); + SET_IVOR(8, SystemCall); + SET_IVOR(9, AuxillaryProcessorUnavailable); + SET_IVOR(10, Decrementer); + SET_IVOR(11, FixedIntervalTimer); + SET_IVOR(12, WatchdogTimer); + SET_IVOR(13, DataTLBError); + SET_IVOR(14, InstructionTLBError); + SET_IVOR(15, Debug); + SET_IVOR(32, SPEUnavailable); + SET_IVOR(33, SPEFloatingPointData); + SET_IVOR(34, SPEFloatingPointRound); +#ifndef CONFIG_E200 + SET_IVOR(35, PerformanceMonitor); +#endif + + /* Establish the interrupt vector base */ + lis r4,interrupt_base@h /* IVPR only uses the high 16-bits */ + mtspr SPRN_IVPR,r4 + + /* Setup the defaults for TLB entries */ + li r2,(MAS4_TSIZED(BOOKE_PAGESZ_4K))@l +#ifdef CONFIG_E200 + oris r2,r2,MAS4_TLBSELD(1)@h +#endif + mtspr SPRN_MAS4, r2 + +#if 0 + /* Enable DOZE */ + mfspr r2,SPRN_HID0 + oris r2,r2,HID0_DOZE@h + mtspr SPRN_HID0, r2 +#endif +#ifdef CONFIG_E200 + /* enable dedicated debug exception handling resources (Debug APU) */ + mfspr r2,SPRN_HID0 + ori r2,r2,HID0_DAPUEN@l + mtspr SPRN_HID0,r2 +#endif + +#if !defined(CONFIG_BDI_SWITCH) + /* + * The Abatron BDI JTAG debugger does not tolerate others + * mucking with the debug registers. + */ + lis r2,DBCR0_IDM@h + mtspr SPRN_DBCR0,r2 + /* clear any residual debug events */ + li r2,-1 + mtspr SPRN_DBSR,r2 +#endif + + /* + * This is where the main kernel code starts. + */ + + /* ptr to current */ + lis r2,init_task@h + ori r2,r2,init_task@l + + /* ptr to current thread */ + addi r4,r2,THREAD /* init task's THREAD */ + mtspr SPRN_SPRG3,r4 + + /* stack */ + lis r1,init_thread_union@h + ori r1,r1,init_thread_union@l + li r0,0 + stwu r0,THREAD_SIZE-STACK_FRAME_OVERHEAD(r1) + + bl early_init + + mfspr r3,SPRN_TLB1CFG + andi. r3,r3,0xfff + lis r4,num_tlbcam_entries@ha + stw r3,num_tlbcam_entries@l(r4) +/* + * Decide what sort of machine this is and initialize the MMU. + */ + mr r3,r31 + mr r4,r30 + mr r5,r29 + mr r6,r28 + mr r7,r27 + bl machine_init + bl MMU_init + + /* Setup PTE pointers for the Abatron bdiGDB */ + lis r6, swapper_pg_dir@h + ori r6, r6, swapper_pg_dir@l + lis r5, abatron_pteptrs@h + ori r5, r5, abatron_pteptrs@l + lis r4, KERNELBASE@h + ori r4, r4, KERNELBASE@l + stw r5, 0(r4) /* Save abatron_pteptrs at a fixed location */ + stw r6, 0(r5) + + /* Let's move on */ + lis r4,start_kernel@h + ori r4,r4,start_kernel@l + lis r3,MSR_KERNEL@h + ori r3,r3,MSR_KERNEL@l + mtspr SPRN_SRR0,r4 + mtspr SPRN_SRR1,r3 + rfi /* change context and jump to start_kernel */ + +/* Macros to hide the PTE size differences + * + * FIND_PTE -- walks the page tables given EA & pgdir pointer + * r10 -- EA of fault + * r11 -- PGDIR pointer + * r12 -- free + * label 2: is the bailout case + * + * if we find the pte (fall through): + * r11 is low pte word + * r12 is pointer to the pte + */ +#ifdef CONFIG_PTE_64BIT +#define PTE_FLAGS_OFFSET 4 +#define FIND_PTE \ + rlwinm r12, r10, 13, 19, 29; /* Compute pgdir/pmd offset */ \ + lwzx r11, r12, r11; /* Get pgd/pmd entry */ \ + rlwinm. r12, r11, 0, 0, 20; /* Extract pt base address */ \ + beq 2f; /* Bail if no table */ \ + rlwimi r12, r10, 23, 20, 28; /* Compute pte address */ \ + lwz r11, 4(r12); /* Get pte entry */ +#else +#define PTE_FLAGS_OFFSET 0 +#define FIND_PTE \ + rlwimi r11, r10, 12, 20, 29; /* Create L1 (pgdir/pmd) address */ \ + lwz r11, 0(r11); /* Get L1 entry */ \ + rlwinm. r12, r11, 0, 0, 19; /* Extract L2 (pte) base address */ \ + beq 2f; /* Bail if no table */ \ + rlwimi r12, r10, 22, 20, 29; /* Compute PTE address */ \ + lwz r11, 0(r12); /* Get Linux PTE */ +#endif + +/* + * Interrupt vector entry code + * + * The Book E MMUs are always on so we don't need to handle + * interrupts in real mode as with previous PPC processors. In + * this case we handle interrupts in the kernel virtual address + * space. + * + * Interrupt vectors are dynamically placed relative to the + * interrupt prefix as determined by the address of interrupt_base. + * The interrupt vectors offsets are programmed using the labels + * for each interrupt vector entry. + * + * Interrupt vectors must be aligned on a 16 byte boundary. + * We align on a 32 byte cache line boundary for good measure. + */ + +interrupt_base: + /* Critical Input Interrupt */ + CRITICAL_EXCEPTION(0x0100, CriticalInput, UnknownException) + + /* Machine Check Interrupt */ +#ifdef CONFIG_E200 + /* no RFMCI, MCSRRs on E200 */ + CRITICAL_EXCEPTION(0x0200, MachineCheck, MachineCheckException) +#else + MCHECK_EXCEPTION(0x0200, MachineCheck, MachineCheckException) +#endif + + /* Data Storage Interrupt */ + START_EXCEPTION(DataStorage) + mtspr SPRN_SPRG0, r10 /* Save some working registers */ + mtspr SPRN_SPRG1, r11 + mtspr SPRN_SPRG4W, r12 + mtspr SPRN_SPRG5W, r13 + mfcr r11 + mtspr SPRN_SPRG7W, r11 + + /* + * Check if it was a store fault, if not then bail + * because a user tried to access a kernel or + * read-protected page. Otherwise, get the + * offending address and handle it. + */ + mfspr r10, SPRN_ESR + andis. r10, r10, ESR_ST@h + beq 2f + + mfspr r10, SPRN_DEAR /* Get faulting address */ + + /* If we are faulting a kernel address, we have to use the + * kernel page tables. + */ + lis r11, TASK_SIZE@h + ori r11, r11, TASK_SIZE@l + cmplw 0, r10, r11 + bge 2f + + /* Get the PGD for the current thread */ +3: + mfspr r11,SPRN_SPRG3 + lwz r11,PGDIR(r11) +4: + FIND_PTE + + /* Are _PAGE_USER & _PAGE_RW set & _PAGE_HWWRITE not? */ + andi. r13, r11, _PAGE_RW|_PAGE_USER|_PAGE_HWWRITE + cmpwi 0, r13, _PAGE_RW|_PAGE_USER + bne 2f /* Bail if not */ + + /* Update 'changed'. */ + ori r11, r11, _PAGE_DIRTY|_PAGE_ACCESSED|_PAGE_HWWRITE + stw r11, PTE_FLAGS_OFFSET(r12) /* Update Linux page table */ + + /* MAS2 not updated as the entry does exist in the tlb, this + fault taken to detect state transition (eg: COW -> DIRTY) + */ + andi. r11, r11, _PAGE_HWEXEC + rlwimi r11, r11, 31, 27, 27 /* SX <- _PAGE_HWEXEC */ + ori r11, r11, (MAS3_UW|MAS3_SW|MAS3_UR|MAS3_SR)@l /* set static perms */ + + /* update search PID in MAS6, AS = 0 */ + mfspr r12, SPRN_PID0 + slwi r12, r12, 16 + mtspr SPRN_MAS6, r12 + + /* find the TLB index that caused the fault. It has to be here. */ + tlbsx 0, r10 + + /* only update the perm bits, assume the RPN is fine */ + mfspr r12, SPRN_MAS3 + rlwimi r12, r11, 0, 20, 31 + mtspr SPRN_MAS3,r12 + tlbwe + + /* Done...restore registers and get out of here. */ + mfspr r11, SPRN_SPRG7R + mtcr r11 + mfspr r13, SPRN_SPRG5R + mfspr r12, SPRN_SPRG4R + mfspr r11, SPRN_SPRG1 + mfspr r10, SPRN_SPRG0 + rfi /* Force context change */ + +2: + /* + * The bailout. Restore registers to pre-exception conditions + * and call the heavyweights to help us out. + */ + mfspr r11, SPRN_SPRG7R + mtcr r11 + mfspr r13, SPRN_SPRG5R + mfspr r12, SPRN_SPRG4R + mfspr r11, SPRN_SPRG1 + mfspr r10, SPRN_SPRG0 + b data_access + + /* Instruction Storage Interrupt */ + INSTRUCTION_STORAGE_EXCEPTION + + /* External Input Interrupt */ + EXCEPTION(0x0500, ExternalInput, do_IRQ, EXC_XFER_LITE) + + /* Alignment Interrupt */ + ALIGNMENT_EXCEPTION + + /* Program Interrupt */ + PROGRAM_EXCEPTION + + /* Floating Point Unavailable Interrupt */ +#ifdef CONFIG_PPC_FPU + FP_UNAVAILABLE_EXCEPTION +#else +#ifdef CONFIG_E200 + /* E200 treats 'normal' floating point instructions as FP Unavail exception */ + EXCEPTION(0x0800, FloatingPointUnavailable, ProgramCheckException, EXC_XFER_EE) +#else + EXCEPTION(0x0800, FloatingPointUnavailable, UnknownException, EXC_XFER_EE) +#endif +#endif + + /* System Call Interrupt */ + START_EXCEPTION(SystemCall) + NORMAL_EXCEPTION_PROLOG + EXC_XFER_EE_LITE(0x0c00, DoSyscall) + + /* Auxillary Processor Unavailable Interrupt */ + EXCEPTION(0x2900, AuxillaryProcessorUnavailable, UnknownException, EXC_XFER_EE) + + /* Decrementer Interrupt */ + DECREMENTER_EXCEPTION + + /* Fixed Internal Timer Interrupt */ + /* TODO: Add FIT support */ + EXCEPTION(0x3100, FixedIntervalTimer, UnknownException, EXC_XFER_EE) + + /* Watchdog Timer Interrupt */ +#ifdef CONFIG_BOOKE_WDT + CRITICAL_EXCEPTION(0x3200, WatchdogTimer, WatchdogException) +#else + CRITICAL_EXCEPTION(0x3200, WatchdogTimer, UnknownException) +#endif + + /* Data TLB Error Interrupt */ + START_EXCEPTION(DataTLBError) + mtspr SPRN_SPRG0, r10 /* Save some working registers */ + mtspr SPRN_SPRG1, r11 + mtspr SPRN_SPRG4W, r12 + mtspr SPRN_SPRG5W, r13 + mfcr r11 + mtspr SPRN_SPRG7W, r11 + mfspr r10, SPRN_DEAR /* Get faulting address */ + + /* If we are faulting a kernel address, we have to use the + * kernel page tables. + */ + lis r11, TASK_SIZE@h + ori r11, r11, TASK_SIZE@l + cmplw 5, r10, r11 + blt 5, 3f + lis r11, swapper_pg_dir@h + ori r11, r11, swapper_pg_dir@l + + mfspr r12,SPRN_MAS1 /* Set TID to 0 */ + rlwinm r12,r12,0,16,1 + mtspr SPRN_MAS1,r12 + + b 4f + + /* Get the PGD for the current thread */ +3: + mfspr r11,SPRN_SPRG3 + lwz r11,PGDIR(r11) + +4: + FIND_PTE + andi. r13, r11, _PAGE_PRESENT /* Is the page present? */ + beq 2f /* Bail if not present */ + +#ifdef CONFIG_PTE_64BIT + lwz r13, 0(r12) +#endif + ori r11, r11, _PAGE_ACCESSED + stw r11, PTE_FLAGS_OFFSET(r12) + + /* Jump to common tlb load */ + b finish_tlb_load +2: + /* The bailout. Restore registers to pre-exception conditions + * and call the heavyweights to help us out. + */ + mfspr r11, SPRN_SPRG7R + mtcr r11 + mfspr r13, SPRN_SPRG5R + mfspr r12, SPRN_SPRG4R + mfspr r11, SPRN_SPRG1 + mfspr r10, SPRN_SPRG0 + b data_access + + /* Instruction TLB Error Interrupt */ + /* + * Nearly the same as above, except we get our + * information from different registers and bailout + * to a different point. + */ + START_EXCEPTION(InstructionTLBError) + mtspr SPRN_SPRG0, r10 /* Save some working registers */ + mtspr SPRN_SPRG1, r11 + mtspr SPRN_SPRG4W, r12 + mtspr SPRN_SPRG5W, r13 + mfcr r11 + mtspr SPRN_SPRG7W, r11 + mfspr r10, SPRN_SRR0 /* Get faulting address */ + + /* If we are faulting a kernel address, we have to use the + * kernel page tables. + */ + lis r11, TASK_SIZE@h + ori r11, r11, TASK_SIZE@l + cmplw 5, r10, r11 + blt 5, 3f + lis r11, swapper_pg_dir@h + ori r11, r11, swapper_pg_dir@l + + mfspr r12,SPRN_MAS1 /* Set TID to 0 */ + rlwinm r12,r12,0,16,1 + mtspr SPRN_MAS1,r12 + + b 4f + + /* Get the PGD for the current thread */ +3: + mfspr r11,SPRN_SPRG3 + lwz r11,PGDIR(r11) + +4: + FIND_PTE + andi. r13, r11, _PAGE_PRESENT /* Is the page present? */ + beq 2f /* Bail if not present */ + +#ifdef CONFIG_PTE_64BIT + lwz r13, 0(r12) +#endif + ori r11, r11, _PAGE_ACCESSED + stw r11, PTE_FLAGS_OFFSET(r12) + + /* Jump to common TLB load point */ + b finish_tlb_load + +2: + /* The bailout. Restore registers to pre-exception conditions + * and call the heavyweights to help us out. + */ + mfspr r11, SPRN_SPRG7R + mtcr r11 + mfspr r13, SPRN_SPRG5R + mfspr r12, SPRN_SPRG4R + mfspr r11, SPRN_SPRG1 + mfspr r10, SPRN_SPRG0 + b InstructionStorage + +#ifdef CONFIG_SPE + /* SPE Unavailable */ + START_EXCEPTION(SPEUnavailable) + NORMAL_EXCEPTION_PROLOG + bne load_up_spe + addi r3,r1,STACK_FRAME_OVERHEAD + EXC_XFER_EE_LITE(0x2010, KernelSPE) +#else + EXCEPTION(0x2020, SPEUnavailable, UnknownException, EXC_XFER_EE) +#endif /* CONFIG_SPE */ + + /* SPE Floating Point Data */ +#ifdef CONFIG_SPE + EXCEPTION(0x2030, SPEFloatingPointData, SPEFloatingPointException, EXC_XFER_EE); +#else + EXCEPTION(0x2040, SPEFloatingPointData, UnknownException, EXC_XFER_EE) +#endif /* CONFIG_SPE */ + + /* SPE Floating Point Round */ + EXCEPTION(0x2050, SPEFloatingPointRound, UnknownException, EXC_XFER_EE) + + /* Performance Monitor */ + EXCEPTION(0x2060, PerformanceMonitor, PerformanceMonitorException, EXC_XFER_STD) + + + /* Debug Interrupt */ + DEBUG_EXCEPTION + +/* + * Local functions + */ + + /* + * Data TLB exceptions will bail out to this point + * if they can't resolve the lightweight TLB fault. + */ +data_access: + NORMAL_EXCEPTION_PROLOG + mfspr r5,SPRN_ESR /* Grab the ESR, save it, pass arg3 */ + stw r5,_ESR(r11) + mfspr r4,SPRN_DEAR /* Grab the DEAR, save it, pass arg2 */ + andis. r10,r5,(ESR_ILK|ESR_DLK)@h + bne 1f + EXC_XFER_EE_LITE(0x0300, handle_page_fault) +1: + addi r3,r1,STACK_FRAME_OVERHEAD + EXC_XFER_EE_LITE(0x0300, CacheLockingException) + +/* + + * Both the instruction and data TLB miss get to this + * point to load the TLB. + * r10 - EA of fault + * r11 - TLB (info from Linux PTE) + * r12, r13 - available to use + * CR5 - results of addr < TASK_SIZE + * MAS0, MAS1 - loaded with proper value when we get here + * MAS2, MAS3 - will need additional info from Linux PTE + * Upon exit, we reload everything and RFI. + */ +finish_tlb_load: + /* + * We set execute, because we don't have the granularity to + * properly set this at the page level (Linux problem). + * Many of these bits are software only. Bits we don't set + * here we (properly should) assume have the appropriate value. + */ + + mfspr r12, SPRN_MAS2 +#ifdef CONFIG_PTE_64BIT + rlwimi r12, r11, 26, 24, 31 /* extract ...WIMGE from pte */ +#else + rlwimi r12, r11, 26, 27, 31 /* extract WIMGE from pte */ +#endif + mtspr SPRN_MAS2, r12 + + bge 5, 1f + + /* is user addr */ + andi. r12, r11, (_PAGE_USER | _PAGE_HWWRITE | _PAGE_HWEXEC) + andi. r10, r11, _PAGE_USER /* Test for _PAGE_USER */ + srwi r10, r12, 1 + or r12, r12, r10 /* Copy user perms into supervisor */ + iseleq r12, 0, r12 + b 2f + + /* is kernel addr */ +1: rlwinm r12, r11, 31, 29, 29 /* Extract _PAGE_HWWRITE into SW */ + ori r12, r12, (MAS3_SX | MAS3_SR) + +#ifdef CONFIG_PTE_64BIT +2: rlwimi r12, r13, 24, 0, 7 /* grab RPN[32:39] */ + rlwimi r12, r11, 24, 8, 19 /* grab RPN[40:51] */ + mtspr SPRN_MAS3, r12 +BEGIN_FTR_SECTION + srwi r10, r13, 8 /* grab RPN[8:31] */ + mtspr SPRN_MAS7, r10 +END_FTR_SECTION_IFSET(CPU_FTR_BIG_PHYS) +#else +2: rlwimi r11, r12, 0, 20, 31 /* Extract RPN from PTE and merge with perms */ + mtspr SPRN_MAS3, r11 +#endif +#ifdef CONFIG_E200 + /* Round robin TLB1 entries assignment */ + mfspr r12, SPRN_MAS0 + + /* Extract TLB1CFG(NENTRY) */ + mfspr r11, SPRN_TLB1CFG + andi. r11, r11, 0xfff + + /* Extract MAS0(NV) */ + andi. r13, r12, 0xfff + addi r13, r13, 1 + cmpw 0, r13, r11 + addi r12, r12, 1 + + /* check if we need to wrap */ + blt 7f + + /* wrap back to first free tlbcam entry */ + lis r13, tlbcam_index@ha + lwz r13, tlbcam_index@l(r13) + rlwimi r12, r13, 0, 20, 31 +7: + mtspr SPRN_MAS0,r12 +#endif /* CONFIG_E200 */ + + tlbwe + + /* Done...restore registers and get out of here. */ + mfspr r11, SPRN_SPRG7R + mtcr r11 + mfspr r13, SPRN_SPRG5R + mfspr r12, SPRN_SPRG4R + mfspr r11, SPRN_SPRG1 + mfspr r10, SPRN_SPRG0 + rfi /* Force context change */ + +#ifdef CONFIG_SPE +/* Note that the SPE support is closely modeled after the AltiVec + * support. Changes to one are likely to be applicable to the + * other! */ +load_up_spe: +/* + * Disable SPE for the task which had SPE previously, + * and save its SPE registers in its thread_struct. + * Enables SPE for use in the kernel on return. + * On SMP we know the SPE units are free, since we give it up every + * switch. -- Kumar + */ + mfmsr r5 + oris r5,r5,MSR_SPE@h + mtmsr r5 /* enable use of SPE now */ + isync +/* + * For SMP, we don't do lazy SPE switching because it just gets too + * horrendously complex, especially when a task switches from one CPU + * to another. Instead we call giveup_spe in switch_to. + */ +#ifndef CONFIG_SMP + lis r3,last_task_used_spe@ha + lwz r4,last_task_used_spe@l(r3) + cmpi 0,r4,0 + beq 1f + addi r4,r4,THREAD /* want THREAD of last_task_used_spe */ + SAVE_32EVRS(0,r10,r4) + evxor evr10, evr10, evr10 /* clear out evr10 */ + evmwumiaa evr10, evr10, evr10 /* evr10 <- ACC = 0 * 0 + ACC */ + li r5,THREAD_ACC + evstddx evr10, r4, r5 /* save off accumulator */ + lwz r5,PT_REGS(r4) + lwz r4,_MSR-STACK_FRAME_OVERHEAD(r5) + lis r10,MSR_SPE@h + andc r4,r4,r10 /* disable SPE for previous task */ + stw r4,_MSR-STACK_FRAME_OVERHEAD(r5) +1: +#endif /* CONFIG_SMP */ + /* enable use of SPE after return */ + oris r9,r9,MSR_SPE@h + mfspr r5,SPRN_SPRG3 /* current task's THREAD (phys) */ + li r4,1 + li r10,THREAD_ACC + stw r4,THREAD_USED_SPE(r5) + evlddx evr4,r10,r5 + evmra evr4,evr4 + REST_32EVRS(0,r10,r5) +#ifndef CONFIG_SMP + subi r4,r5,THREAD + stw r4,last_task_used_spe@l(r3) +#endif /* CONFIG_SMP */ + /* restore registers and return */ +2: REST_4GPRS(3, r11) + lwz r10,_CCR(r11) + REST_GPR(1, r11) + mtcr r10 + lwz r10,_LINK(r11) + mtlr r10 + REST_GPR(10, r11) + mtspr SPRN_SRR1,r9 + mtspr SPRN_SRR0,r12 + REST_GPR(9, r11) + REST_GPR(12, r11) + lwz r11,GPR11(r11) + SYNC + rfi + +/* + * SPE unavailable trap from kernel - print a message, but let + * the task use SPE in the kernel until it returns to user mode. + */ +KernelSPE: + lwz r3,_MSR(r1) + oris r3,r3,MSR_SPE@h + stw r3,_MSR(r1) /* enable use of SPE after return */ + 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 "SPE used in kernel (task=%p, pc=%x) \n" + .align 4,0 + +#endif /* CONFIG_SPE */ + +/* + * Global functions + */ + +/* + * extern void loadcam_entry(unsigned int index) + * + * Load TLBCAM[index] entry in to the L2 CAM MMU + */ +_GLOBAL(loadcam_entry) + lis r4,TLBCAM@ha + addi r4,r4,TLBCAM@l + mulli r5,r3,20 + add r3,r5,r4 + lwz r4,0(r3) + mtspr SPRN_MAS0,r4 + lwz r4,4(r3) + mtspr SPRN_MAS1,r4 + lwz r4,8(r3) + mtspr SPRN_MAS2,r4 + lwz r4,12(r3) + mtspr SPRN_MAS3,r4 + tlbwe + isync + blr + +/* + * extern void giveup_altivec(struct task_struct *prev) + * + * The e500 core does not have an AltiVec unit. + */ +_GLOBAL(giveup_altivec) + blr + +#ifdef CONFIG_SPE +/* + * extern void giveup_spe(struct task_struct *prev) + * + */ +_GLOBAL(giveup_spe) + mfmsr r5 + oris r5,r5,MSR_SPE@h + SYNC + mtmsr r5 /* enable use of SPE now */ + isync + cmpi 0,r3,0 + beqlr- /* if no previous owner, done */ + addi r3,r3,THREAD /* want THREAD of task */ + lwz r5,PT_REGS(r3) + cmpi 0,r5,0 + SAVE_32EVRS(0, r4, r3) + evxor evr6, evr6, evr6 /* clear out evr6 */ + evmwumiaa evr6, evr6, evr6 /* evr6 <- ACC = 0 * 0 + ACC */ + li r4,THREAD_ACC + evstddx evr6, r4, r3 /* save off accumulator */ + mfspr r6,SPRN_SPEFSCR + stw r6,THREAD_SPEFSCR(r3) /* save spefscr register value */ + beq 1f + lwz r4,_MSR-STACK_FRAME_OVERHEAD(r5) + lis r3,MSR_SPE@h + andc r4,r4,r3 /* disable SPE for previous task */ + stw r4,_MSR-STACK_FRAME_OVERHEAD(r5) +1: +#ifndef CONFIG_SMP + li r5,0 + lis r4,last_task_used_spe@ha + stw r5,last_task_used_spe@l(r4) +#endif /* CONFIG_SMP */ + blr +#endif /* CONFIG_SPE */ + +/* + * extern void giveup_fpu(struct task_struct *prev) + * + * Not all FSL Book-E cores have an FPU + */ +#ifndef CONFIG_PPC_FPU +_GLOBAL(giveup_fpu) + blr +#endif + +/* + * extern void abort(void) + * + * At present, this routine just applies a system reset. + */ +_GLOBAL(abort) + li r13,0 + mtspr SPRN_DBCR0,r13 /* disable all debug events */ + mfmsr r13 + ori r13,r13,MSR_DE@l /* Enable Debug Events */ + mtmsr r13 + mfspr r13,SPRN_DBCR0 + lis r13,(DBCR0_IDM|DBCR0_RST_CHIP)@h + mtspr SPRN_DBCR0,r13 + +_GLOBAL(set_context) + +#ifdef CONFIG_BDI_SWITCH + /* Context switch the PTE pointer for the Abatron BDI2000. + * The PGDIR is the second parameter. + */ + lis r5, abatron_pteptrs@h + ori r5, r5, abatron_pteptrs@l + stw r4, 0x4(r5) +#endif + mtspr SPRN_PID,r3 + isync /* Force context change */ + blr + +/* + * 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 +_GLOBAL(sdata) +_GLOBAL(empty_zero_page) + .space 4096 +_GLOBAL(swapper_pg_dir) + .space 4096 + +/* Reserved 4k for the critical exception stack & 4k for the machine + * check stack per CPU for kernel mode exceptions */ + .section .bss + .align 12 +exception_stack_bottom: + .space BOOKE_EXCEPTION_STACK_SIZE * NR_CPUS +_GLOBAL(exception_stack_top) + +/* + * This space gets a copy of optional info passed to us by the bootstrap + * which is used to pass parameters into the kernel like root=/dev/sda1, etc. + */ +_GLOBAL(cmd_line) + .space 512 + +/* + * Room for two PTE pointers, usually the kernel and current user pointers + * to their respective root page table. + */ +abatron_pteptrs: + .space 8 + |