--- /dev/null
+/*
+ * 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/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 */
+ 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 */
+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
+ mtspr SPRN_PID1,r6
+ mtspr SPRN_PID2,r6
+ 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);
+ SET_IVOR(35, PerformanceMonitor);
+
+ /* 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
+ mtspr SPRN_MAS4, r2
+
+#if 0
+ /* Enable DOZE */
+ mfspr r2,SPRN_HID0
+ oris r2,r2,HID0_DOZE@h
+ 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 */
+ MCHECK_EXCEPTION(0x0200, MachineCheck, MachineCheckException)
+
+ /* 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
+ EXCEPTION(0x0800, FloatingPointUnavailable, UnknownException, EXC_XFER_EE)
+#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 */
+ /* TODO: Add watchdog support */
+ CRITICAL_EXCEPTION(0x3200, WatchdogTimer, UnknownException)
+
+ /* 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
+ 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_32EVR(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_32EVR(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_32EVR(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
+
git://git.onelab.eu / linux-2.6.git / blobdiff