OpenCloudOS-Kernel/arch/powerpc/kernel/head_85xx.S

1231 lines
31 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* 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>
*/
#include <linux/init.h>
#include <linux/threads.h>
#include <linux/pgtable.h>
#include <linux/linkage.h>
#include <asm/processor.h>
#include <asm/page.h>
#include <asm/mmu.h>
#include <asm/cputable.h>
#include <asm/thread_info.h>
#include <asm/ppc_asm.h>
#include <asm/asm-offsets.h>
#include <asm/cache.h>
#include <asm/ptrace.h>
#include <asm/export.h>
#include <asm/feature-fixups.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
*
*/
__HEAD
_GLOBAL(_stext);
_GLOBAL(_start);
/*
* Reserve a word at a fixed location to store the address
* of abatron_pteptrs
*/
nop
/* Translate device tree address to physical, save in r30/r31 */
bl get_phys_addr
mr r30,r3
mr r31,r4
li r25,0 /* phys kernel start (low) */
li r24,0 /* CPU number */
li r23,0 /* phys kernel start (high) */
#ifdef CONFIG_RELOCATABLE
LOAD_REG_ADDR_PIC(r3, _stext) /* Get our current runtime base */
/* Translate _stext address to physical, save in r23/r25 */
bl get_phys_addr
mr r23,r3
mr r25,r4
bcl 20,31,$+4
0: mflr r8
addis r3,r8,(is_second_reloc - 0b)@ha
lwz r19,(is_second_reloc - 0b)@l(r3)
/* Check if this is the second relocation. */
cmpwi r19,1
bne 1f
/*
* For the second relocation, we already get the real memstart_addr
* from device tree. So we will map PAGE_OFFSET to memstart_addr,
* then the virtual address of start kernel should be:
* PAGE_OFFSET + (kernstart_addr - memstart_addr)
* Since the offset between kernstart_addr and memstart_addr should
* never be beyond 1G, so we can just use the lower 32bit of them
* for the calculation.
*/
lis r3,PAGE_OFFSET@h
addis r4,r8,(kernstart_addr - 0b)@ha
addi r4,r4,(kernstart_addr - 0b)@l
lwz r5,4(r4)
addis r6,r8,(memstart_addr - 0b)@ha
addi r6,r6,(memstart_addr - 0b)@l
lwz r7,4(r6)
subf r5,r7,r5
add r3,r3,r5
b 2f
1:
/*
* We have the runtime (virtual) address of our base.
* We calculate our shift of offset from a 64M page.
* We could map the 64M page we belong to at PAGE_OFFSET and
* get going from there.
*/
lis r4,KERNELBASE@h
ori r4,r4,KERNELBASE@l
rlwinm r6,r25,0,0x3ffffff /* r6 = PHYS_START % 64M */
rlwinm r5,r4,0,0x3ffffff /* r5 = KERNELBASE % 64M */
subf r3,r5,r6 /* r3 = r6 - r5 */
add r3,r4,r3 /* Required Virtual Address */
2: bl relocate
/*
* For the second relocation, we already set the right tlb entries
* for the kernel space, so skip the code in 85xx_entry_mapping.S
*/
cmpwi r19,1
beq set_ivor
#endif
/* 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
*/
_GLOBAL(__early_start)
LOAD_REG_ADDR_PIC(r20, kernstart_virt_addr)
lwz r20,0(r20)
#define ENTRY_MAPPING_BOOT_SETUP
#include "85xx_entry_mapping.S"
#undef ENTRY_MAPPING_BOOT_SETUP
set_ivor:
/* 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, DebugCrit);
/* 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(BOOK3E_PAGESZ_4K))@l
mtspr SPRN_MAS4, r2
#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
#ifdef CONFIG_SMP
/* Check to see if we're the second processor, and jump
* to the secondary_start code if so
*/
LOAD_REG_ADDR_PIC(r24, boot_cpuid)
lwz r24, 0(r24)
cmpwi r24, -1
mfspr r24,SPRN_PIR
bne __secondary_start
#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_SPRG_THREAD,r4
/* stack */
lis r1,init_thread_union@h
ori r1,r1,init_thread_union@l
li r0,0
stwu r0,THREAD_SIZE-STACK_FRAME_MIN_SIZE(r1)
#ifdef CONFIG_SMP
stw r24, TASK_CPU(r2)
#endif
bl early_init
#ifdef CONFIG_KASAN
bl kasan_early_init
#endif
#ifdef CONFIG_RELOCATABLE
mr r3,r30
mr r4,r31
#ifdef CONFIG_PHYS_64BIT
mr r5,r23
mr r6,r25
#else
mr r5,r25
#endif
bl relocate_init
#endif
#ifdef CONFIG_DYNAMIC_MEMSTART
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
/*
* Decide what sort of machine this is and initialize the MMU.
*/
mr r3,r30
mr r4,r31
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 r3, kernstart_virt_addr@ha
lwz r4, kernstart_virt_addr@l(r3)
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
* r10 is the pshift from the PGD, if we're a hugepage
*/
#ifdef CONFIG_PTE_64BIT
#ifdef CONFIG_HUGETLB_PAGE
#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 */ \
blt 1000f; /* Normal non-huge page */ \
beq 2f; /* Bail if no table */ \
oris r11, r11, PD_HUGE@h; /* Put back address bit */ \
andi. r10, r11, HUGEPD_SHIFT_MASK@l; /* extract size field */ \
xor r12, r10, r11; /* drop size bits from pointer */ \
b 1001f; \
1000: rlwimi r12, r10, 23, 20, 28; /* Compute pte address */ \
li r10, 0; /* clear r10 */ \
1001: lwz r11, 4(r12); /* Get pte entry */
#else
#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 */
#endif /* HUGEPAGE */
#else /* !PTE_64BIT */
#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, CRITICAL, CriticalInput, unknown_exception)
/* Machine Check Interrupt */
MCHECK_EXCEPTION(0x0200, MachineCheck, machine_check_exception)
/* Data Storage Interrupt */
START_EXCEPTION(DataStorage)
NORMAL_EXCEPTION_PROLOG(0x300, DATA_STORAGE)
mfspr r5,SPRN_ESR /* Grab the ESR, save it */
stw r5,_ESR(r11)
mfspr r4,SPRN_DEAR /* Grab the DEAR, save it */
stw r4, _DEAR(r11)
andis. r10,r5,(ESR_ILK|ESR_DLK)@h
bne 1f
prepare_transfer_to_handler
bl do_page_fault
b interrupt_return
1:
prepare_transfer_to_handler
bl CacheLockingException
b interrupt_return
/* Instruction Storage Interrupt */
INSTRUCTION_STORAGE_EXCEPTION
/* External Input Interrupt */
EXCEPTION(0x0500, EXTERNAL, ExternalInput, do_IRQ)
/* Alignment Interrupt */
ALIGNMENT_EXCEPTION
/* Program Interrupt */
PROGRAM_EXCEPTION
/* Floating Point Unavailable Interrupt */
#ifdef CONFIG_PPC_FPU
FP_UNAVAILABLE_EXCEPTION
#else
EXCEPTION(0x0800, FP_UNAVAIL, FloatingPointUnavailable, unknown_exception)
#endif
/* System Call Interrupt */
START_EXCEPTION(SystemCall)
SYSCALL_ENTRY 0xc00 BOOKE_INTERRUPT_SYSCALL SPRN_SRR1
/* Auxiliary Processor Unavailable Interrupt */
EXCEPTION(0x2900, AP_UNAVAIL, AuxillaryProcessorUnavailable, unknown_exception)
/* Decrementer Interrupt */
DECREMENTER_EXCEPTION
/* Fixed Internal Timer Interrupt */
/* TODO: Add FIT support */
EXCEPTION(0x3100, FIT, FixedIntervalTimer, unknown_exception)
/* Watchdog Timer Interrupt */
#ifdef CONFIG_BOOKE_WDT
CRITICAL_EXCEPTION(0x3200, WATCHDOG, WatchdogTimer, WatchdogException)
#else
CRITICAL_EXCEPTION(0x3200, WATCHDOG, WatchdogTimer, unknown_exception)
#endif
/* Data TLB Error Interrupt */
START_EXCEPTION(DataTLBError)
mtspr SPRN_SPRG_WSCRATCH0, r10 /* Save some working registers */
mfspr r10, SPRN_SPRG_THREAD
stw r11, THREAD_NORMSAVE(0)(r10)
#ifdef CONFIG_KVM_BOOKE_HV
BEGIN_FTR_SECTION
mfspr r11, SPRN_SRR1
END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
#endif
stw r12, THREAD_NORMSAVE(1)(r10)
stw r13, THREAD_NORMSAVE(2)(r10)
mfcr r13
stw r13, THREAD_NORMSAVE(3)(r10)
DO_KVM BOOKE_INTERRUPT_DTLB_MISS SPRN_SRR1
START_BTB_FLUSH_SECTION
mfspr r11, SPRN_SRR1
andi. r10,r11,MSR_PR
beq 1f
BTB_FLUSH(r10)
1:
END_BTB_FLUSH_SECTION
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_SPRG_THREAD
lwz r11,PGDIR(r11)
#ifdef CONFIG_PPC_KUAP
mfspr r12, SPRN_MAS1
rlwinm. r12,r12,0,0x3fff0000
beq 2f /* KUAP fault */
#endif
4:
/* Mask of required permission bits. Note that while we
* do copy ESR:ST to _PAGE_RW position as trying to write
* to an RO page is pretty common, we don't do it with
* _PAGE_DIRTY. We could do it, but it's a fairly rare
* event so I'd rather take the overhead when it happens
* rather than adding an instruction here. We should measure
* whether the whole thing is worth it in the first place
* as we could avoid loading SPRN_ESR completely in the first
* place...
*
* TODO: Is it worth doing that mfspr & rlwimi in the first
* place or can we save a couple of instructions here ?
*/
mfspr r12,SPRN_ESR
#ifdef CONFIG_PTE_64BIT
li r13,_PAGE_PRESENT
oris r13,r13,_PAGE_ACCESSED@h
#else
li r13,_PAGE_PRESENT|_PAGE_ACCESSED
#endif
rlwimi r13,r12,11,29,29
FIND_PTE
andc. r13,r13,r11 /* Check permission */
#ifdef CONFIG_PTE_64BIT
#ifdef CONFIG_SMP
subf r13,r11,r12 /* create false data dep */
lwzx r13,r11,r13 /* Get upper pte bits */
#else
lwz r13,0(r12) /* Get upper pte bits */
#endif
#endif
bne 2f /* Bail if permission/valid mismatch */
/* 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 r10, SPRN_SPRG_THREAD
lwz r11, THREAD_NORMSAVE(3)(r10)
mtcr r11
lwz r13, THREAD_NORMSAVE(2)(r10)
lwz r12, THREAD_NORMSAVE(1)(r10)
lwz r11, THREAD_NORMSAVE(0)(r10)
mfspr r10, SPRN_SPRG_RSCRATCH0
b DataStorage
/* 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_SPRG_WSCRATCH0, r10 /* Save some working registers */
mfspr r10, SPRN_SPRG_THREAD
stw r11, THREAD_NORMSAVE(0)(r10)
#ifdef CONFIG_KVM_BOOKE_HV
BEGIN_FTR_SECTION
mfspr r11, SPRN_SRR1
END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
#endif
stw r12, THREAD_NORMSAVE(1)(r10)
stw r13, THREAD_NORMSAVE(2)(r10)
mfcr r13
stw r13, THREAD_NORMSAVE(3)(r10)
DO_KVM BOOKE_INTERRUPT_ITLB_MISS SPRN_SRR1
START_BTB_FLUSH_SECTION
mfspr r11, SPRN_SRR1
andi. r10,r11,MSR_PR
beq 1f
BTB_FLUSH(r10)
1:
END_BTB_FLUSH_SECTION
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
/* Make up the required permissions for kernel code */
#ifdef CONFIG_PTE_64BIT
li r13,_PAGE_PRESENT | _PAGE_BAP_SX
oris r13,r13,_PAGE_ACCESSED@h
#else
li r13,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC
#endif
b 4f
/* Get the PGD for the current thread */
3:
mfspr r11,SPRN_SPRG_THREAD
lwz r11,PGDIR(r11)
#ifdef CONFIG_PPC_KUAP
mfspr r12, SPRN_MAS1
rlwinm. r12,r12,0,0x3fff0000
beq 2f /* KUAP fault */
#endif
/* Make up the required permissions for user code */
#ifdef CONFIG_PTE_64BIT
li r13,_PAGE_PRESENT | _PAGE_BAP_UX
oris r13,r13,_PAGE_ACCESSED@h
#else
li r13,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC
#endif
4:
FIND_PTE
andc. r13,r13,r11 /* Check permission */
#ifdef CONFIG_PTE_64BIT
#ifdef CONFIG_SMP
subf r13,r11,r12 /* create false data dep */
lwzx r13,r11,r13 /* Get upper pte bits */
#else
lwz r13,0(r12) /* Get upper pte bits */
#endif
#endif
bne 2f /* Bail if permission mismatch */
/* 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 r10, SPRN_SPRG_THREAD
lwz r11, THREAD_NORMSAVE(3)(r10)
mtcr r11
lwz r13, THREAD_NORMSAVE(2)(r10)
lwz r12, THREAD_NORMSAVE(1)(r10)
lwz r11, THREAD_NORMSAVE(0)(r10)
mfspr r10, SPRN_SPRG_RSCRATCH0
b InstructionStorage
/* Define SPE handlers for e500v2 */
#ifdef CONFIG_SPE
/* SPE Unavailable */
START_EXCEPTION(SPEUnavailable)
NORMAL_EXCEPTION_PROLOG(0x2010, SPE_UNAVAIL)
beq 1f
bl load_up_spe
b fast_exception_return
1: prepare_transfer_to_handler
bl KernelSPE
b interrupt_return
#elif defined(CONFIG_SPE_POSSIBLE)
EXCEPTION(0x2020, SPE_UNAVAIL, SPEUnavailable, unknown_exception)
#endif /* CONFIG_SPE_POSSIBLE */
/* SPE Floating Point Data */
#ifdef CONFIG_SPE
START_EXCEPTION(SPEFloatingPointData)
NORMAL_EXCEPTION_PROLOG(0x2030, SPE_FP_DATA)
prepare_transfer_to_handler
bl SPEFloatingPointException
REST_NVGPRS(r1)
b interrupt_return
/* SPE Floating Point Round */
START_EXCEPTION(SPEFloatingPointRound)
NORMAL_EXCEPTION_PROLOG(0x2050, SPE_FP_ROUND)
prepare_transfer_to_handler
bl SPEFloatingPointRoundException
REST_NVGPRS(r1)
b interrupt_return
#elif defined(CONFIG_SPE_POSSIBLE)
EXCEPTION(0x2040, SPE_FP_DATA, SPEFloatingPointData, unknown_exception)
EXCEPTION(0x2050, SPE_FP_ROUND, SPEFloatingPointRound, unknown_exception)
#endif /* CONFIG_SPE_POSSIBLE */
/* Performance Monitor */
EXCEPTION(0x2060, PERFORMANCE_MONITOR, PerformanceMonitor, \
performance_monitor_exception)
EXCEPTION(0x2070, DOORBELL, Doorbell, doorbell_exception)
CRITICAL_EXCEPTION(0x2080, DOORBELL_CRITICAL, \
CriticalDoorbell, unknown_exception)
/* Debug Interrupt */
DEBUG_DEBUG_EXCEPTION
DEBUG_CRIT_EXCEPTION
GUEST_DOORBELL_EXCEPTION
CRITICAL_EXCEPTION(0, GUEST_DBELL_CRIT, CriticalGuestDoorbell, \
unknown_exception)
/* Hypercall */
EXCEPTION(0, HV_SYSCALL, Hypercall, unknown_exception)
/* Embedded Hypervisor Privilege */
EXCEPTION(0, HV_PRIV, Ehvpriv, unknown_exception)
interrupt_end:
/*
* Local functions
*/
/*
* Both the instruction and data TLB miss get to this
* point to load the TLB.
* r10 - tsize encoding (if HUGETLB_PAGE) or available to use
* r11 - TLB (info from Linux PTE)
* r12 - available to use
* r13 - upper bits of PTE (if PTE_64BIT) or 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:
#ifdef CONFIG_HUGETLB_PAGE
cmpwi 6, r10, 0 /* check for huge page */
beq 6, finish_tlb_load_cont /* !huge */
/* Alas, we need more scratch registers for hugepages */
mfspr r12, SPRN_SPRG_THREAD
stw r14, THREAD_NORMSAVE(4)(r12)
stw r15, THREAD_NORMSAVE(5)(r12)
stw r16, THREAD_NORMSAVE(6)(r12)
stw r17, THREAD_NORMSAVE(7)(r12)
/* Get the next_tlbcam_idx percpu var */
#ifdef CONFIG_SMP
lwz r15, TASK_CPU-THREAD(r12)
lis r14, __per_cpu_offset@h
ori r14, r14, __per_cpu_offset@l
rlwinm r15, r15, 2, 0, 29
lwzx r16, r14, r15
#else
li r16, 0
#endif
lis r17, next_tlbcam_idx@h
ori r17, r17, next_tlbcam_idx@l
add r17, r17, r16 /* r17 = *next_tlbcam_idx */
lwz r15, 0(r17) /* r15 = next_tlbcam_idx */
lis r14, MAS0_TLBSEL(1)@h /* select TLB1 (TLBCAM) */
rlwimi r14, r15, 16, 4, 15 /* next_tlbcam_idx entry */
mtspr SPRN_MAS0, r14
/* Extract TLB1CFG(NENTRY) */
mfspr r16, SPRN_TLB1CFG
andi. r16, r16, 0xfff
/* Update next_tlbcam_idx, wrapping when necessary */
addi r15, r15, 1
cmpw r15, r16
blt 100f
lis r14, tlbcam_index@h
ori r14, r14, tlbcam_index@l
lwz r15, 0(r14)
100: stw r15, 0(r17)
/*
* Calc MAS1_TSIZE from r10 (which has pshift encoded)
* tlb_enc = (pshift - 10).
*/
subi r15, r10, 10
mfspr r16, SPRN_MAS1
rlwimi r16, r15, 7, 20, 24
mtspr SPRN_MAS1, r16
/* copy the pshift for use later */
mr r14, r10
/* fall through */
#endif /* CONFIG_HUGETLB_PAGE */
/*
* 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.
*/
finish_tlb_load_cont:
#ifdef CONFIG_PTE_64BIT
rlwinm r12, r11, 32-2, 26, 31 /* Move in perm bits */
andi. r10, r11, _PAGE_DIRTY
bne 1f
li r10, MAS3_SW | MAS3_UW
andc r12, r12, r10
1: rlwimi r12, r13, 20, 0, 11 /* grab RPN[32:43] */
rlwimi r12, r11, 20, 12, 19 /* grab RPN[44:51] */
2: mtspr SPRN_MAS3, r12
BEGIN_MMU_FTR_SECTION
srwi r10, r13, 12 /* grab RPN[12:31] */
mtspr SPRN_MAS7, r10
END_MMU_FTR_SECTION_IFSET(MMU_FTR_BIG_PHYS)
#else
li r10, (_PAGE_EXEC | _PAGE_PRESENT)
mr r13, r11
rlwimi r10, r11, 31, 29, 29 /* extract _PAGE_DIRTY into SW */
and r12, r11, r10
andi. r10, r11, _PAGE_USER /* Test for _PAGE_USER */
slwi r10, r12, 1
or r10, r10, r12
rlwinm r10, r10, 0, ~_PAGE_EXEC /* Clear SX on user pages */
iseleq r12, r12, r10
rlwimi r13, r12, 0, 20, 31 /* Get RPN from PTE, merge w/ perms */
mtspr SPRN_MAS3, r13
#endif
mfspr r12, SPRN_MAS2
#ifdef CONFIG_PTE_64BIT
rlwimi r12, r11, 32-19, 27, 31 /* extract WIMGE from pte */
#else
rlwimi r12, r11, 26, 27, 31 /* extract WIMGE from pte */
#endif
#ifdef CONFIG_HUGETLB_PAGE
beq 6, 3f /* don't mask if page isn't huge */
li r13, 1
slw r13, r13, r14
subi r13, r13, 1
rlwinm r13, r13, 0, 0, 19 /* bottom bits used for WIMGE/etc */
andc r12, r12, r13 /* mask off ea bits within the page */
#endif
3: mtspr SPRN_MAS2, r12
tlb_write_entry:
tlbwe
/* Done...restore registers and get out of here. */
mfspr r10, SPRN_SPRG_THREAD
#ifdef CONFIG_HUGETLB_PAGE
beq 6, 8f /* skip restore for 4k page faults */
lwz r14, THREAD_NORMSAVE(4)(r10)
lwz r15, THREAD_NORMSAVE(5)(r10)
lwz r16, THREAD_NORMSAVE(6)(r10)
lwz r17, THREAD_NORMSAVE(7)(r10)
#endif
8: lwz r11, THREAD_NORMSAVE(3)(r10)
mtcr r11
lwz r13, THREAD_NORMSAVE(2)(r10)
lwz r12, THREAD_NORMSAVE(1)(r10)
lwz r11, THREAD_NORMSAVE(0)(r10)
mfspr r10, SPRN_SPRG_RSCRATCH0
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! */
_GLOBAL(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
/* enable use of SPE after return */
oris r9,r9,MSR_SPE@h
mfspr r5,SPRN_SPRG_THREAD /* 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,THREAD_EVR0)
blr
/*
* 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 */
#ifdef CONFIG_PRINTK
lis r3,87f@h
ori r3,r3,87f@l
mr r4,r2 /* current */
lwz r5,_NIP(r1)
bl _printk
#endif
b interrupt_return
#ifdef CONFIG_PRINTK
87: .string "SPE used in kernel (task=%p, pc=%x) \n"
#endif
.align 4,0
#endif /* CONFIG_SPE */
/*
* Translate the effec addr in r3 to phys addr. The phys addr will be put
* into r3(higher 32bit) and r4(lower 32bit)
*/
SYM_FUNC_START_LOCAL(get_phys_addr)
mfmsr r8
mfspr r9,SPRN_PID
rlwinm r9,r9,16,0x3fff0000 /* turn PID into MAS6[SPID] */
rlwimi r9,r8,28,0x00000001 /* turn MSR[DS] into MAS6[SAS] */
mtspr SPRN_MAS6,r9
tlbsx 0,r3 /* must succeed */
mfspr r8,SPRN_MAS1
mfspr r12,SPRN_MAS3
rlwinm r9,r8,25,0x1f /* r9 = log2(page size) */
li r10,1024
slw r10,r10,r9 /* r10 = page size */
addi r10,r10,-1
and r11,r3,r10 /* r11 = page offset */
andc r4,r12,r10 /* r4 = page base */
or r4,r4,r11 /* r4 = devtree phys addr */
#ifdef CONFIG_PHYS_64BIT
mfspr r3,SPRN_MAS7
#endif
blr
SYM_FUNC_END(get_phys_addr)
/*
* Global functions
*/
#ifdef CONFIG_PPC_E500
#ifndef CONFIG_PPC_E500MC
/* Adjust or setup IVORs for e500v1/v2 */
_GLOBAL(__setup_e500_ivors)
li r3,DebugCrit@l
mtspr SPRN_IVOR15,r3
li r3,SPEUnavailable@l
mtspr SPRN_IVOR32,r3
li r3,SPEFloatingPointData@l
mtspr SPRN_IVOR33,r3
li r3,SPEFloatingPointRound@l
mtspr SPRN_IVOR34,r3
li r3,PerformanceMonitor@l
mtspr SPRN_IVOR35,r3
sync
blr
#else
/* Adjust or setup IVORs for e500mc */
_GLOBAL(__setup_e500mc_ivors)
li r3,DebugDebug@l
mtspr SPRN_IVOR15,r3
li r3,PerformanceMonitor@l
mtspr SPRN_IVOR35,r3
li r3,Doorbell@l
mtspr SPRN_IVOR36,r3
li r3,CriticalDoorbell@l
mtspr SPRN_IVOR37,r3
sync
blr
/* setup ehv ivors for */
_GLOBAL(__setup_ehv_ivors)
li r3,GuestDoorbell@l
mtspr SPRN_IVOR38,r3
li r3,CriticalGuestDoorbell@l
mtspr SPRN_IVOR39,r3
li r3,Hypercall@l
mtspr SPRN_IVOR40,r3
li r3,Ehvpriv@l
mtspr SPRN_IVOR41,r3
sync
blr
#endif /* CONFIG_PPC_E500MC */
#endif /* CONFIG_PPC_E500 */
#ifdef CONFIG_SPE
/*
* extern void __giveup_spe(struct task_struct *prev)
*
*/
_GLOBAL(__giveup_spe)
addi r3,r3,THREAD /* want THREAD of task */
lwz r5,PT_REGS(r3)
cmpi 0,r5,0
SAVE_32EVRS(0, r4, r3, THREAD_EVR0)
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 */
beq 1f
lwz r4,_MSR-STACK_INT_FRAME_REGS(r5)
lis r3,MSR_SPE@h
andc r4,r4,r3 /* disable SPE for previous task */
stw r4,_MSR-STACK_INT_FRAME_REGS(r5)
1:
blr
#endif /* CONFIG_SPE */
/*
* 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
#ifdef CONFIG_SMP
/* When we get here, r24 needs to hold the CPU # */
.globl __secondary_start
__secondary_start:
LOAD_REG_ADDR_PIC(r3, tlbcam_index)
lwz r3,0(r3)
mtctr r3
li r26,0 /* r26 safe? */
bl switch_to_as1
mr r27,r3 /* tlb entry */
/* Load each CAM entry */
1: mr r3,r26
bl loadcam_entry
addi r26,r26,1
bdnz 1b
mr r3,r27 /* tlb entry */
LOAD_REG_ADDR_PIC(r4, memstart_addr)
lwz r4,0(r4)
mr r5,r25 /* phys kernel start */
rlwinm r5,r5,0,~0x3ffffff /* aligned 64M */
subf r4,r5,r4 /* memstart_addr - phys kernel start */
lis r7,KERNELBASE@h
ori r7,r7,KERNELBASE@l
cmpw r20,r7 /* if kernstart_virt_addr != KERNELBASE, randomized */
beq 2f
li r4,0
2: li r5,0 /* no device tree */
li r6,0 /* not boot cpu */
bl restore_to_as0
lis r3,__secondary_hold_acknowledge@h
ori r3,r3,__secondary_hold_acknowledge@l
stw r24,0(r3)
li r3,0
mr r4,r24 /* Why? */
bl call_setup_cpu
/* get current's stack and current */
lis r2,secondary_current@ha
lwz r2,secondary_current@l(r2)
lwz r1,TASK_STACK(r2)
/* stack */
addi r1,r1,THREAD_SIZE-STACK_FRAME_MIN_SIZE
li r0,0
stw r0,0(r1)
/* ptr to current thread */
addi r4,r2,THREAD /* address of our thread_struct */
mtspr SPRN_SPRG_THREAD,r4
/* Setup the defaults for TLB entries */
li r4,(MAS4_TSIZED(BOOK3E_PAGESZ_4K))@l
mtspr SPRN_MAS4,r4
/* Jump to start_secondary */
lis r4,MSR_KERNEL@h
ori r4,r4,MSR_KERNEL@l
lis r3,start_secondary@h
ori r3,r3,start_secondary@l
mtspr SPRN_SRR0,r3
mtspr SPRN_SRR1,r4
sync
rfi
sync
.globl __secondary_hold_acknowledge
__secondary_hold_acknowledge:
.long -1
#endif
/*
* Create a 64M tlb by address and entry
* r3 - entry
* r4 - virtual address
* r5/r6 - physical address
*/
_GLOBAL(create_kaslr_tlb_entry)
lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */
rlwimi r7,r3,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r6) */
mtspr SPRN_MAS0,r7 /* Write MAS0 */
lis r3,(MAS1_VALID|MAS1_IPROT)@h
ori r3,r3,(MAS1_TSIZE(BOOK3E_PAGESZ_64M))@l
mtspr SPRN_MAS1,r3 /* Write MAS1 */
lis r3,MAS2_EPN_MASK(BOOK3E_PAGESZ_64M)@h
ori r3,r3,MAS2_EPN_MASK(BOOK3E_PAGESZ_64M)@l
and r3,r3,r4
ori r3,r3,MAS2_M_IF_NEEDED@l
mtspr SPRN_MAS2,r3 /* Write MAS2(EPN) */
#ifdef CONFIG_PHYS_64BIT
ori r8,r6,(MAS3_SW|MAS3_SR|MAS3_SX)
mtspr SPRN_MAS3,r8 /* Write MAS3(RPN) */
mtspr SPRN_MAS7,r5
#else
ori r8,r5,(MAS3_SW|MAS3_SR|MAS3_SX)
mtspr SPRN_MAS3,r8 /* Write MAS3(RPN) */
#endif
tlbwe /* Write TLB */
isync
sync
blr
/*
* Return to the start of the relocated kernel and run again
* r3 - virtual address of fdt
* r4 - entry of the kernel
*/
_GLOBAL(reloc_kernel_entry)
mfmsr r7
rlwinm r7, r7, 0, ~(MSR_IS | MSR_DS)
mtspr SPRN_SRR0,r4
mtspr SPRN_SRR1,r7
rfi
/*
* Create a tlb entry with the same effective and physical address as
* the tlb entry used by the current running code. But set the TS to 1.
* Then switch to the address space 1. It will return with the r3 set to
* the ESEL of the new created tlb.
*/
_GLOBAL(switch_to_as1)
mflr r5
/* Find a entry not used */
mfspr r3,SPRN_TLB1CFG
andi. r3,r3,0xfff
mfspr r4,SPRN_PID
rlwinm r4,r4,16,0x3fff0000 /* turn PID into MAS6[SPID] */
mtspr SPRN_MAS6,r4
1: lis r4,0x1000 /* Set MAS0(TLBSEL) = 1 */
addi r3,r3,-1
rlwimi r4,r3,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r3) */
mtspr SPRN_MAS0,r4
tlbre
mfspr r4,SPRN_MAS1
andis. r4,r4,MAS1_VALID@h
bne 1b
/* Get the tlb entry used by the current running code */
bcl 20,31,$+4
0: mflr r4
tlbsx 0,r4
mfspr r4,SPRN_MAS1
ori r4,r4,MAS1_TS /* Set the TS = 1 */
mtspr SPRN_MAS1,r4
mfspr r4,SPRN_MAS0
rlwinm r4,r4,0,~MAS0_ESEL_MASK
rlwimi r4,r3,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r3) */
mtspr SPRN_MAS0,r4
tlbwe
isync
sync
mfmsr r4
ori r4,r4,MSR_IS | MSR_DS
mtspr SPRN_SRR0,r5
mtspr SPRN_SRR1,r4
sync
rfi
/*
* Restore to the address space 0 and also invalidate the tlb entry created
* by switch_to_as1.
* r3 - the tlb entry which should be invalidated
* r4 - __pa(PAGE_OFFSET in AS1) - __pa(PAGE_OFFSET in AS0)
* r5 - device tree virtual address. If r4 is 0, r5 is ignored.
* r6 - boot cpu
*/
_GLOBAL(restore_to_as0)
mflr r0
bcl 20,31,$+4
0: mflr r9
addi r9,r9,1f - 0b
/*
* We may map the PAGE_OFFSET in AS0 to a different physical address,
* so we need calculate the right jump and device tree address based
* on the offset passed by r4.
*/
add r9,r9,r4
add r5,r5,r4
add r0,r0,r4
2: mfmsr r7
li r8,(MSR_IS | MSR_DS)
andc r7,r7,r8
mtspr SPRN_SRR0,r9
mtspr SPRN_SRR1,r7
sync
rfi
/* Invalidate the temporary tlb entry for AS1 */
1: lis r9,0x1000 /* Set MAS0(TLBSEL) = 1 */
rlwimi r9,r3,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r3) */
mtspr SPRN_MAS0,r9
tlbre
mfspr r9,SPRN_MAS1
rlwinm r9,r9,0,2,31 /* Clear MAS1 Valid and IPPROT */
mtspr SPRN_MAS1,r9
tlbwe
isync
cmpwi r4,0
cmpwi cr1,r6,0
cror eq,4*cr1+eq,eq
bne 3f /* offset != 0 && is_boot_cpu */
mtlr r0
blr
/*
* The PAGE_OFFSET will map to a different physical address,
* jump to _start to do another relocation again.
*/
3: mr r3,r5
bl _start