Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity
kernel-fxtec-pro1x/arch/powerpc/kernel/head_fsl_booke.S
Kumar Gala 37dd2badcf [POWERPC] 85xx: Add support for relocatable kernel (and booting at non-zero) 
Added support to allow an 85xx kernel to be run from a non-zero physical
address (useful for cooperative asymmetric multiprocessing situations and
kdump).  The support can be configured at compile time by setting
CONFIG_PAGE_OFFSET, CONFIG_KERNEL_START, and CONFIG_PHYSICAL_START as
desired.

Alternatively, the kernel build can set CONFIG_RELOCATABLE.  Setting this
config option causes the kernel to determine at runtime the physical
addresses of CONFIG_PAGE_OFFSET and CONFIG_KERNEL_START.  If
CONFIG_RELOCATABLE is set, then CONFIG_PHYSICAL_START has no meaning.
However, CONFIG_PHYSICAL_START will always be used to set the LOAD program
header physical address field in the resulting ELF image.

Currently we are limited to running at a physical address that is a
multiple of 256M.  This is due to how we map TLBs to cover
lowmem.  This should be fixed to allow 64M or maybe even 16M alignment
in the future.  It is considered an error to try and run a kernel at a
non-aligned physical address.

All the magic for this support is accomplished by proper initialization
of the kernel memory subsystem and use of ARCH_PFN_OFFSET.

The use of ARCH_PFN_OFFSET only affects normal memory and not IO mappings.
ioremap uses map_page and isn't affected by ARCH_PFN_OFFSET.

/dev/mem continues to allow access to any physical address in the system
regardless of how CONFIG_PHYSICAL_START is set.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-24 20:58:01 +10:00

1097 lines
27 KiB
ArmAsm
Raw Blame History

/*
* 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 <galak@kernel.crashing.org>
*
* 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/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
*
*/
.section .text.head, "ax"
_ENTRY(_stext);
_ENTRY(_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 r25,0 /* phys kernel start (low) */
li r24,0 /* CPU number */
li r23,0 /* phys kernel start (high) */
/* 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 64M of kernel memory. Any boot info passed from the
* bootloader needs to live in this first 64M.
*
* 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
/* grab and fixup the RPN */
mfspr r6,SPRN_MAS1 /* extract MAS1[SIZE] */
rlwinm r6,r6,25,27,30
li r8,-1
addi r6,r6,10
slw r6,r8,r6 /* convert to mask */
bl 1f /* Find our address */
1: mflr r7
mfspr r8,SPRN_MAS3
#ifdef CONFIG_PHYS_64BIT
mfspr r23,SPRN_MAS7
#endif
and r8,r6,r8
subfic r9,r6,-4096
and r9,r9,r7
or r25,r8,r9
ori r8,r25,(MAS3_SX|MAS3_SW|MAS3_SR)
/* 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
mtspr SPRN_MAS3,r8
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
mfspr r6,SPRN_MAS1
rlwinm r6,r6,0,2,0 /* clear IPROT */
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_64M))@l
mtspr SPRN_MAS1,r6
li r7,0
lis r6,PAGE_OFFSET@h
ori r6,r6,PAGE_OFFSET@l
rlwimi r6,r7,0,20,31
mtspr SPRN_MAS2,r6
mtspr SPRN_MAS3,r8
tlbwe
/* 7. Jump to KERNELBASE mapping */
lis r6,KERNELBASE@h
ori r6,r6,KERNELBASE@l
rlwimi r6,r7,0,20,31
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
mfspr r8,SPRN_MAS1
rlwinm r8,r8,0,2,0 /* clear IPROT */
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, DebugDebug);
#if defined(CONFIG_E500)
SET_IVOR(15, DebugCrit);
#endif
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
isync
/* 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
#ifdef CONFIG_RELOCATABLE
lis r3,kernstart_addr@ha
la r3,kernstart_addr@l(r3)
#ifdef CONFIG_PHYS_64BIT
stw r23,0(r3)
stw r25,4(r3)
#else
stw r25,0(r3)
#endif
#endif
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, unknown_exception)
/* Machine Check Interrupt */
#ifdef CONFIG_E200
/* no RFMCI, MCSRRs on E200 */
CRITICAL_EXCEPTION(0x0200, MachineCheck, machine_check_exception)
#else
MCHECK_EXCEPTION(0x0200, MachineCheck, machine_check_exception)
#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, PAGE_OFFSET@h
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, program_check_exception, EXC_XFER_EE)
#else
EXCEPTION(0x0800, FloatingPointUnavailable, unknown_exception, 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, unknown_exception, EXC_XFER_EE)
/* Decrementer Interrupt */
DECREMENTER_EXCEPTION
/* Fixed Internal Timer Interrupt */
/* TODO: Add FIT support */
EXCEPTION(0x3100, FixedIntervalTimer, unknown_exception, EXC_XFER_EE)
/* Watchdog Timer Interrupt */
#ifdef CONFIG_BOOKE_WDT
CRITICAL_EXCEPTION(0x3200, WatchdogTimer, WatchdogException)
#else
CRITICAL_EXCEPTION(0x3200, WatchdogTimer, unknown_exception)
#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, PAGE_OFFSET@h
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, PAGE_OFFSET@h
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, unknown_exception, EXC_XFER_EE)
#endif /* CONFIG_SPE */
/* SPE Floating Point Data */
#ifdef CONFIG_SPE
EXCEPTION(0x2030, SPEFloatingPointData, SPEFloatingPointException, EXC_XFER_EE);
#else
EXCEPTION(0x2040, SPEFloatingPointData, unknown_exception, EXC_XFER_EE)
#endif /* CONFIG_SPE */
/* SPE Floating Point Round */
EXCEPTION(0x2050, SPEFloatingPointRound, unknown_exception, EXC_XFER_EE)
/* Performance Monitor */
EXCEPTION(0x2060, PerformanceMonitor, performance_monitor_exception, EXC_XFER_STD)
/* Debug Interrupt */
DEBUG_DEBUG_EXCEPTION
#if defined(CONFIG_E500)
DEBUG_CRIT_EXCEPTION
#endif
/*
* 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 >= PAGE_OFFSET
* 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)
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
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 */
isync
mfmsr r13
ori r13,r13,MSR_DE@l /* Enable Debug Events */
mtmsr r13
isync
mfspr r13,SPRN_DBCR0
lis r13,(DBCR0_IDM|DBCR0_RST_CHIP)@h
mtspr SPRN_DBCR0,r13
isync
_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
.align 12
.globl sdata
sdata:
.globl empty_zero_page
empty_zero_page:
.space 4096
.globl swapper_pg_dir
swapper_pg_dir:
.space PGD_TABLE_SIZE
/* 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
.globl exception_stack_top
exception_stack_top:
/*
* Room for two PTE pointers, usually the kernel and current user pointers
* to their respective root page table.
*/
abatron_pteptrs:
.space 8
Reference in a new issue View git blame Copy permalink