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FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //sys/arm/arm/swtch.S |
/* $NetBSD: cpuswitch.S,v 1.41 2003/11/15 08:44:18 scw Exp $ */
/*-
* Copyright 2003 Wasabi Systems, Inc.
* All rights reserved.
*
* Written by Steve C. Woodford for Wasabi Systems, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed for the NetBSD Project by
* Wasabi Systems, Inc.
* 4. The name of Wasabi Systems, Inc. may not be used to endorse
* or promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*-
* Copyright (c) 1994-1998 Mark Brinicombe.
* Copyright (c) 1994 Brini.
* All rights reserved.
*
* This code is derived from software written for Brini by Mark Brinicombe
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Brini.
* 4. The name of the company nor the name of the author may be used to
* endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY BRINI ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL BRINI OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* RiscBSD kernel project
*
* cpuswitch.S
*
* cpu switching functions
*
* Created : 15/10/94
*
*/
#include "assym.s"
#include <machine/asm.h>
#include <machine/asmacros.h>
#include <machine/armreg.h>
__FBSDID("$FreeBSD: release/9.1.0/sys/arm/arm/swtch.S 188581 2009-02-13 16:00:19Z cognet $");
/*
* New experimental definitions of IRQdisable and IRQenable
* These keep FIQ's enabled since FIQ's are special.
*/
#define DOMAIN_CLIENT 0x01
#define IRQdisable \
mrs r14, cpsr ; \
orr r14, r14, #(I32_bit) ; \
msr cpsr_c, r14 ; \
#define IRQenable \
mrs r14, cpsr ; \
bic r14, r14, #(I32_bit) ; \
msr cpsr_c, r14 ; \
/*
* These are used for switching the translation table/DACR.
* Since the vector page can be invalid for a short time, we must
* disable both regular IRQs *and* FIQs.
*
* XXX: This is not necessary if the vector table is relocated.
*/
#define IRQdisableALL \
mrs r14, cpsr ; \
orr r14, r14, #(I32_bit | F32_bit) ; \
msr cpsr_c, r14
#define IRQenableALL \
mrs r14, cpsr ; \
bic r14, r14, #(I32_bit | F32_bit) ; \
msr cpsr_c, r14
.Lcurpcb:
.word _C_LABEL(__pcpu) + PC_CURPCB
.Lcpufuncs:
.word _C_LABEL(cpufuncs)
.Lblock_userspace_access:
.word _C_LABEL(block_userspace_access)
.Lcpu_do_powersave:
.word _C_LABEL(cpu_do_powersave)
.Lblocked_lock:
.word _C_LABEL(blocked_lock)
ENTRY(cpu_throw)
mov r5, r1
/*
* r5 = newtd
*/
ldr r7, [r5, #(TD_PCB)] /* r7 = new thread's PCB */
/* Switch to lwp0 context */
ldr r9, .Lcpufuncs
mov lr, pc
ldr pc, [r9, #CF_IDCACHE_WBINV_ALL]
ldr r0, [r7, #(PCB_PL1VEC)]
ldr r1, [r7, #(PCB_DACR)]
/*
* r0 = Pointer to L1 slot for vector_page (or NULL)
* r1 = lwp0's DACR
* r5 = lwp0
* r6 = exit func
* r7 = lwp0's PCB
* r9 = cpufuncs
*/
/*
* Ensure the vector table is accessible by fixing up lwp0's L1
*/
cmp r0, #0 /* No need to fixup vector table? */
ldrne r3, [r0] /* But if yes, fetch current value */
ldrne r2, [r7, #(PCB_L1VEC)] /* Fetch new vector_page value */
mcr p15, 0, r1, c3, c0, 0 /* Update DACR for lwp0's context */
cmpne r3, r2 /* Stuffing the same value? */
strne r2, [r0] /* Store if not. */
#ifdef PMAP_INCLUDE_PTE_SYNC
/*
* Need to sync the cache to make sure that last store is
* visible to the MMU.
*/
movne r1, #4
movne lr, pc
ldrne pc, [r9, #CF_DCACHE_WB_RANGE]
#endif /* PMAP_INCLUDE_PTE_SYNC */
/*
* Note: We don't do the same optimisation as cpu_switch() with
* respect to avoiding flushing the TLB if we're switching to
* the same L1 since this process' VM space may be about to go
* away, so we don't want *any* turds left in the TLB.
*/
/* Switch the memory to the new process */
ldr r0, [r7, #(PCB_PAGEDIR)]
mov lr, pc
ldr pc, [r9, #CF_CONTEXT_SWITCH]
/* Restore all the save registers */
#ifndef _ARM_ARCH_5E
add r1, r7, #PCB_R8
ldmia r1, {r8-r13}
#else
ldr r8, [r7, #(PCB_R8)]
ldr r9, [r7, #(PCB_R9)]
ldr r10, [r7, #(PCB_R10)]
ldr r11, [r7, #(PCB_R11)]
ldr r12, [r7, #(PCB_R12)]
ldr r13, [r7, #(PCB_SP)]
#endif
/* We have a new curthread now so make a note it */
ldr r6, .Lcurthread
str r5, [r6]
/* Set the new tp */
ldr r6, [r5, #(TD_MD + MD_TP)]
ldr r4, =ARM_TP_ADDRESS
str r6, [r4]
ldr r6, [r5, #(TD_MD + MD_RAS_START)]
str r6, [r4, #4] /* ARM_RAS_START */
ldr r6, [r5, #(TD_MD + MD_RAS_END)]
str r6, [r4, #8] /* ARM_RAS_END */
/* Hook in a new pcb */
ldr r6, .Lcurpcb
str r7, [r6]
ldmfd sp!, {r4-r7, pc}
ENTRY(cpu_switch)
stmfd sp!, {r4-r7, lr}
mov r6, r2 /* Save the mutex */
.Lswitch_resume:
/* rem: r0 = old lwp */
/* rem: interrupts are disabled */
#ifdef MULTIPROCESSOR
/* XXX use curcpu() */
ldr r2, .Lcpu_info_store
str r2, [r6, #(L_CPU)]
#endif
/* Process is now on a processor. */
/* We have a new curthread now so make a note it */
ldr r7, .Lcurthread
str r1, [r7]
/* Hook in a new pcb */
ldr r7, .Lcurpcb
ldr r2, [r1, #TD_PCB]
str r2, [r7]
/* rem: r1 = new process */
/* rem: interrupts are enabled */
/* Stage two : Save old context */
/* Get the user structure for the old thread. */
ldr r2, [r0, #(TD_PCB)]
mov r4, r0 /* Save the old thread. */
/* Save all the registers in the old thread's pcb */
#ifndef _ARM_ARCH_5E
add r7, r2, #(PCB_R8)
stmia r7, {r8-r13}
#else
strd r8, [r2, #(PCB_R8)]
strd r10, [r2, #(PCB_R10)]
strd r12, [r2, #(PCB_R12)]
#endif
str pc, [r2, #(PCB_PC)]
/*
* NOTE: We can now use r8-r13 until it is time to restore
* them for the new process.
*/
/* Store the old tp */
ldr r3, =ARM_TP_ADDRESS
ldr r9, [r3]
str r9, [r0, #(TD_MD + MD_TP)]
ldr r9, [r3, #4]
str r9, [r0, #(TD_MD + MD_RAS_START)]
ldr r9, [r3, #8]
str r9, [r0, #(TD_MD + MD_RAS_END)]
/* Set the new tp */
ldr r9, [r1, #(TD_MD + MD_TP)]
str r9, [r3]
ldr r9, [r1, #(TD_MD + MD_RAS_START)]
str r9, [r3, #4]
ldr r9, [r1, #(TD_MD + MD_RAS_END)]
str r9, [r3, #8]
/* Get the user structure for the new process in r9 */
ldr r9, [r1, #(TD_PCB)]
/* r1 now free! */
mrs r3, cpsr
/*
* We can do that, since
* PSR_SVC32_MODE|PSR_UND32_MODE == MSR_UND32_MODE
*/
orr r8, r3, #(PSR_UND32_MODE)
msr cpsr_c, r8
str sp, [r2, #(PCB_UND_SP)]
msr cpsr_c, r3 /* Restore the old mode */
/* rem: r8 = old PCB */
/* rem: r9 = new PCB */
/* rem: interrupts are enabled */
/* What else needs to be saved Only FPA stuff when that is supported */
/* Third phase : restore saved context */
/* rem: r8 = old PCB */
/* rem: r9 = new PCB */
/* rem: interrupts are enabled */
ldr r5, [r9, #(PCB_DACR)] /* r5 = new DACR */
mov r2, #DOMAIN_CLIENT
cmp r5, r2, lsl #(PMAP_DOMAIN_KERNEL * 2) /* Sw to kernel thread? */
beq .Lcs_context_switched /* Yup. Don't flush cache */
mrc p15, 0, r0, c3, c0, 0 /* r0 = old DACR */
/*
* Get the new L1 table pointer into r11. If we're switching to
* an LWP with the same address space as the outgoing one, we can
* skip the cache purge and the TTB load.
*
* To avoid data dep stalls that would happen anyway, we try
* and get some useful work done in the mean time.
*/
mrc p15, 0, r10, c2, c0, 0 /* r10 = old L1 */
ldr r11, [r9, #(PCB_PAGEDIR)] /* r11 = new L1 */
teq r10, r11 /* Same L1? */
cmpeq r0, r5 /* Same DACR? */
beq .Lcs_context_switched /* yes! */
/*
* Definately need to flush the cache.
*/
ldr r1, .Lcpufuncs
mov lr, pc
ldr pc, [r1, #CF_IDCACHE_WBINV_ALL]
.Lcs_cache_purge_skipped:
/* rem: r6 = lock */
/* rem: r9 = new PCB */
/* rem: r10 = old L1 */
/* rem: r11 = new L1 */
mov r2, #0x00000000
ldr r7, [r9, #(PCB_PL1VEC)]
/*
* Ensure the vector table is accessible by fixing up the L1
*/
cmp r7, #0 /* No need to fixup vector table? */
ldrne r2, [r7] /* But if yes, fetch current value */
ldrne r0, [r9, #(PCB_L1VEC)] /* Fetch new vector_page value */
mcr p15, 0, r5, c3, c0, 0 /* Update DACR for new context */
cmpne r2, r0 /* Stuffing the same value? */
#ifndef PMAP_INCLUDE_PTE_SYNC
strne r0, [r7] /* Nope, update it */
#else
beq .Lcs_same_vector
str r0, [r7] /* Otherwise, update it */
/*
* Need to sync the cache to make sure that last store is
* visible to the MMU.
*/
ldr r2, .Lcpufuncs
mov r0, r7
mov r1, #4
mov lr, pc
ldr pc, [r2, #CF_DCACHE_WB_RANGE]
.Lcs_same_vector:
#endif /* PMAP_INCLUDE_PTE_SYNC */
cmp r10, r11 /* Switching to the same L1? */
ldr r10, .Lcpufuncs
beq .Lcs_same_l1 /* Yup. */
/*
* Do a full context switch, including full TLB flush.
*/
mov r0, r11
mov lr, pc
ldr pc, [r10, #CF_CONTEXT_SWITCH]
b .Lcs_context_switched
/*
* We're switching to a different process in the same L1.
* In this situation, we only need to flush the TLB for the
* vector_page mapping, and even then only if r7 is non-NULL.
*/
.Lcs_same_l1:
cmp r7, #0
movne r0, #0 /* We *know* vector_page's VA is 0x0 */
movne lr, pc
ldrne pc, [r10, #CF_TLB_FLUSHID_SE]
/*
* We can do that, since
* PSR_SVC32_MODE|PSR_UND32_MODE == MSR_UND32_MODE
*/
.Lcs_context_switched:
/* Release the old thread */
str r6, [r4, #TD_LOCK]
ldr r6, .Lblocked_lock
ldr r3, .Lcurthread
ldr r3, [r3]
1:
ldr r4, [r3, #TD_LOCK]
cmp r4, r6
beq 1b
/* XXXSCW: Safe to re-enable FIQs here */
/* rem: r9 = new PCB */
mrs r3, cpsr
/*
* We can do that, since
* PSR_SVC32_MODE|PSR_UND32_MODE == MSR_UND32_MODE
*/
orr r2, r3, #(PSR_UND32_MODE)
msr cpsr_c, r2
ldr sp, [r9, #(PCB_UND_SP)]
msr cpsr_c, r3 /* Restore the old mode */
/* Restore all the save registers */
#ifndef _ARM_ARCH_5E
add r7, r9, #PCB_R8
ldmia r7, {r8-r13}
sub r7, r7, #PCB_R8 /* restore PCB pointer */
#else
mov r7, r9
ldr r8, [r7, #(PCB_R8)]
ldr r9, [r7, #(PCB_R9)]
ldr r10, [r7, #(PCB_R10)]
ldr r11, [r7, #(PCB_R11)]
ldr r12, [r7, #(PCB_R12)]
ldr r13, [r7, #(PCB_SP)]
#endif
/* rem: r6 = lock */
/* rem: r7 = new pcb */
#ifdef ARMFPE
add r0, r7, #(USER_SIZE) & 0x00ff
add r0, r0, #(USER_SIZE) & 0xff00
bl _C_LABEL(arm_fpe_core_changecontext)
#endif
/* rem: r5 = new lwp's proc */
/* rem: r6 = lock */
/* rem: r7 = new PCB */
.Lswitch_return:
/*
* Pull the registers that got pushed when either savectx() or
* cpu_switch() was called and return.
*/
ldmfd sp!, {r4-r7, pc}
#ifdef DIAGNOSTIC
.Lswitch_bogons:
adr r0, .Lswitch_panic_str
bl _C_LABEL(panic)
1: nop
b 1b
.Lswitch_panic_str:
.asciz "cpu_switch: sched_qs empty with non-zero sched_whichqs!\n"
#endif
ENTRY(savectx)
stmfd sp!, {r4-r7, lr}
/*
* r0 = pcb
*/
/* Store all the registers in the process's pcb */
add r2, r0, #(PCB_R8)
stmia r2, {r8-r13}
ldmfd sp!, {r4-r7, pc}
ENTRY(fork_trampoline)
mov r1, r5
mov r2, sp
mov r0, r4
mov fp, #0
bl _C_LABEL(fork_exit)
/* Kill irq"s */
mrs r0, cpsr
orr r0, r0, #(I32_bit|F32_bit)
msr cpsr_c, r0
DO_AST
PULLFRAME
movs pc, lr /* Exit */
AST_LOCALS