mirror of
https://github.com/torvalds/linux
synced 2024-11-05 18:23:50 +00:00
ae95bfbb2b
Patch from Lennert Buytenhek
This patch makes the iWMMXt context switch hook use the generic
thread notifier infrastructure that was recently merged in commit
d6551e884c.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
317 lines
7.5 KiB
ArmAsm
317 lines
7.5 KiB
ArmAsm
/*
|
|
* linux/arch/arm/kernel/iwmmxt.S
|
|
*
|
|
* XScale iWMMXt (Concan) context switching and handling
|
|
*
|
|
* Initial code:
|
|
* Copyright (c) 2003, Intel Corporation
|
|
*
|
|
* Full lazy switching support, optimizations and more, by Nicolas Pitre
|
|
* Copyright (c) 2003-2004, MontaVista Software, Inc.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/linkage.h>
|
|
#include <asm/ptrace.h>
|
|
#include <asm/thread_info.h>
|
|
#include <asm/asm-offsets.h>
|
|
|
|
#define MMX_WR0 (0x00)
|
|
#define MMX_WR1 (0x08)
|
|
#define MMX_WR2 (0x10)
|
|
#define MMX_WR3 (0x18)
|
|
#define MMX_WR4 (0x20)
|
|
#define MMX_WR5 (0x28)
|
|
#define MMX_WR6 (0x30)
|
|
#define MMX_WR7 (0x38)
|
|
#define MMX_WR8 (0x40)
|
|
#define MMX_WR9 (0x48)
|
|
#define MMX_WR10 (0x50)
|
|
#define MMX_WR11 (0x58)
|
|
#define MMX_WR12 (0x60)
|
|
#define MMX_WR13 (0x68)
|
|
#define MMX_WR14 (0x70)
|
|
#define MMX_WR15 (0x78)
|
|
#define MMX_WCSSF (0x80)
|
|
#define MMX_WCASF (0x84)
|
|
#define MMX_WCGR0 (0x88)
|
|
#define MMX_WCGR1 (0x8C)
|
|
#define MMX_WCGR2 (0x90)
|
|
#define MMX_WCGR3 (0x94)
|
|
|
|
#define MMX_SIZE (0x98)
|
|
|
|
.text
|
|
|
|
/*
|
|
* Lazy switching of Concan coprocessor context
|
|
*
|
|
* r10 = struct thread_info pointer
|
|
* r9 = ret_from_exception
|
|
* lr = undefined instr exit
|
|
*
|
|
* called from prefetch exception handler with interrupts disabled
|
|
*/
|
|
|
|
ENTRY(iwmmxt_task_enable)
|
|
|
|
mrc p15, 0, r2, c15, c1, 0
|
|
tst r2, #0x3 @ CP0 and CP1 accessible?
|
|
movne pc, lr @ if so no business here
|
|
orr r2, r2, #0x3 @ enable access to CP0 and CP1
|
|
mcr p15, 0, r2, c15, c1, 0
|
|
|
|
ldr r3, =concan_owner
|
|
add r0, r10, #TI_IWMMXT_STATE @ get task Concan save area
|
|
ldr r2, [sp, #60] @ current task pc value
|
|
ldr r1, [r3] @ get current Concan owner
|
|
str r0, [r3] @ this task now owns Concan regs
|
|
sub r2, r2, #4 @ adjust pc back
|
|
str r2, [sp, #60]
|
|
|
|
mrc p15, 0, r2, c2, c0, 0
|
|
mov r2, r2 @ cpwait
|
|
|
|
teq r1, #0 @ test for last ownership
|
|
mov lr, r9 @ normal exit from exception
|
|
beq concan_load @ no owner, skip save
|
|
|
|
concan_save:
|
|
|
|
tmrc r2, wCon
|
|
|
|
@ CUP? wCx
|
|
tst r2, #0x1
|
|
beq 1f
|
|
|
|
concan_dump:
|
|
|
|
wstrw wCSSF, [r1, #MMX_WCSSF]
|
|
wstrw wCASF, [r1, #MMX_WCASF]
|
|
wstrw wCGR0, [r1, #MMX_WCGR0]
|
|
wstrw wCGR1, [r1, #MMX_WCGR1]
|
|
wstrw wCGR2, [r1, #MMX_WCGR2]
|
|
wstrw wCGR3, [r1, #MMX_WCGR3]
|
|
|
|
1: @ MUP? wRn
|
|
tst r2, #0x2
|
|
beq 2f
|
|
|
|
wstrd wR0, [r1, #MMX_WR0]
|
|
wstrd wR1, [r1, #MMX_WR1]
|
|
wstrd wR2, [r1, #MMX_WR2]
|
|
wstrd wR3, [r1, #MMX_WR3]
|
|
wstrd wR4, [r1, #MMX_WR4]
|
|
wstrd wR5, [r1, #MMX_WR5]
|
|
wstrd wR6, [r1, #MMX_WR6]
|
|
wstrd wR7, [r1, #MMX_WR7]
|
|
wstrd wR8, [r1, #MMX_WR8]
|
|
wstrd wR9, [r1, #MMX_WR9]
|
|
wstrd wR10, [r1, #MMX_WR10]
|
|
wstrd wR11, [r1, #MMX_WR11]
|
|
wstrd wR12, [r1, #MMX_WR12]
|
|
wstrd wR13, [r1, #MMX_WR13]
|
|
wstrd wR14, [r1, #MMX_WR14]
|
|
wstrd wR15, [r1, #MMX_WR15]
|
|
|
|
2: teq r0, #0 @ anything to load?
|
|
moveq pc, lr
|
|
|
|
concan_load:
|
|
|
|
@ Load wRn
|
|
wldrd wR0, [r0, #MMX_WR0]
|
|
wldrd wR1, [r0, #MMX_WR1]
|
|
wldrd wR2, [r0, #MMX_WR2]
|
|
wldrd wR3, [r0, #MMX_WR3]
|
|
wldrd wR4, [r0, #MMX_WR4]
|
|
wldrd wR5, [r0, #MMX_WR5]
|
|
wldrd wR6, [r0, #MMX_WR6]
|
|
wldrd wR7, [r0, #MMX_WR7]
|
|
wldrd wR8, [r0, #MMX_WR8]
|
|
wldrd wR9, [r0, #MMX_WR9]
|
|
wldrd wR10, [r0, #MMX_WR10]
|
|
wldrd wR11, [r0, #MMX_WR11]
|
|
wldrd wR12, [r0, #MMX_WR12]
|
|
wldrd wR13, [r0, #MMX_WR13]
|
|
wldrd wR14, [r0, #MMX_WR14]
|
|
wldrd wR15, [r0, #MMX_WR15]
|
|
|
|
@ Load wCx
|
|
wldrw wCSSF, [r0, #MMX_WCSSF]
|
|
wldrw wCASF, [r0, #MMX_WCASF]
|
|
wldrw wCGR0, [r0, #MMX_WCGR0]
|
|
wldrw wCGR1, [r0, #MMX_WCGR1]
|
|
wldrw wCGR2, [r0, #MMX_WCGR2]
|
|
wldrw wCGR3, [r0, #MMX_WCGR3]
|
|
|
|
@ clear CUP/MUP (only if r1 != 0)
|
|
teq r1, #0
|
|
mov r2, #0
|
|
moveq pc, lr
|
|
tmcr wCon, r2
|
|
mov pc, lr
|
|
|
|
/*
|
|
* Back up Concan regs to save area and disable access to them
|
|
* (mainly for gdb or sleep mode usage)
|
|
*
|
|
* r0 = struct thread_info pointer of target task or NULL for any
|
|
*/
|
|
|
|
ENTRY(iwmmxt_task_disable)
|
|
|
|
stmfd sp!, {r4, lr}
|
|
|
|
mrs ip, cpsr
|
|
orr r2, ip, #PSR_I_BIT @ disable interrupts
|
|
msr cpsr_c, r2
|
|
|
|
ldr r3, =concan_owner
|
|
add r2, r0, #TI_IWMMXT_STATE @ get task Concan save area
|
|
ldr r1, [r3] @ get current Concan owner
|
|
teq r1, #0 @ any current owner?
|
|
beq 1f @ no: quit
|
|
teq r0, #0 @ any owner?
|
|
teqne r1, r2 @ or specified one?
|
|
bne 1f @ no: quit
|
|
|
|
mrc p15, 0, r4, c15, c1, 0
|
|
orr r4, r4, #0x3 @ enable access to CP0 and CP1
|
|
mcr p15, 0, r4, c15, c1, 0
|
|
mov r0, #0 @ nothing to load
|
|
str r0, [r3] @ no more current owner
|
|
mrc p15, 0, r2, c2, c0, 0
|
|
mov r2, r2 @ cpwait
|
|
bl concan_save
|
|
|
|
bic r4, r4, #0x3 @ disable access to CP0 and CP1
|
|
mcr p15, 0, r4, c15, c1, 0
|
|
mrc p15, 0, r2, c2, c0, 0
|
|
mov r2, r2 @ cpwait
|
|
|
|
1: msr cpsr_c, ip @ restore interrupt mode
|
|
ldmfd sp!, {r4, pc}
|
|
|
|
/*
|
|
* Copy Concan state to given memory address
|
|
*
|
|
* r0 = struct thread_info pointer of target task
|
|
* r1 = memory address where to store Concan state
|
|
*
|
|
* this is called mainly in the creation of signal stack frames
|
|
*/
|
|
|
|
ENTRY(iwmmxt_task_copy)
|
|
|
|
mrs ip, cpsr
|
|
orr r2, ip, #PSR_I_BIT @ disable interrupts
|
|
msr cpsr_c, r2
|
|
|
|
ldr r3, =concan_owner
|
|
add r2, r0, #TI_IWMMXT_STATE @ get task Concan save area
|
|
ldr r3, [r3] @ get current Concan owner
|
|
teq r2, r3 @ does this task own it...
|
|
beq 1f
|
|
|
|
@ current Concan values are in the task save area
|
|
msr cpsr_c, ip @ restore interrupt mode
|
|
mov r0, r1
|
|
mov r1, r2
|
|
mov r2, #MMX_SIZE
|
|
b memcpy
|
|
|
|
1: @ this task owns Concan regs -- grab a copy from there
|
|
mov r0, #0 @ nothing to load
|
|
mov r2, #3 @ save all regs
|
|
mov r3, lr @ preserve return address
|
|
bl concan_dump
|
|
msr cpsr_c, ip @ restore interrupt mode
|
|
mov pc, r3
|
|
|
|
/*
|
|
* Restore Concan state from given memory address
|
|
*
|
|
* r0 = struct thread_info pointer of target task
|
|
* r1 = memory address where to get Concan state from
|
|
*
|
|
* this is used to restore Concan state when unwinding a signal stack frame
|
|
*/
|
|
|
|
ENTRY(iwmmxt_task_restore)
|
|
|
|
mrs ip, cpsr
|
|
orr r2, ip, #PSR_I_BIT @ disable interrupts
|
|
msr cpsr_c, r2
|
|
|
|
ldr r3, =concan_owner
|
|
add r2, r0, #TI_IWMMXT_STATE @ get task Concan save area
|
|
ldr r3, [r3] @ get current Concan owner
|
|
bic r2, r2, #0x7 @ 64-bit alignment
|
|
teq r2, r3 @ does this task own it...
|
|
beq 1f
|
|
|
|
@ this task doesn't own Concan regs -- use its save area
|
|
msr cpsr_c, ip @ restore interrupt mode
|
|
mov r0, r2
|
|
mov r2, #MMX_SIZE
|
|
b memcpy
|
|
|
|
1: @ this task owns Concan regs -- load them directly
|
|
mov r0, r1
|
|
mov r1, #0 @ don't clear CUP/MUP
|
|
mov r3, lr @ preserve return address
|
|
bl concan_load
|
|
msr cpsr_c, ip @ restore interrupt mode
|
|
mov pc, r3
|
|
|
|
/*
|
|
* Concan handling on task switch
|
|
*
|
|
* r0 = next thread_info pointer
|
|
*
|
|
* Called only from the iwmmxt notifier with task preemption disabled.
|
|
*/
|
|
ENTRY(iwmmxt_task_switch)
|
|
|
|
mrc p15, 0, r1, c15, c1, 0
|
|
tst r1, #0x3 @ CP0 and CP1 accessible?
|
|
bne 1f @ yes: block them for next task
|
|
|
|
ldr r2, =concan_owner
|
|
add r3, r0, #TI_IWMMXT_STATE @ get next task Concan save area
|
|
ldr r2, [r2] @ get current Concan owner
|
|
teq r2, r3 @ next task owns it?
|
|
movne pc, lr @ no: leave Concan disabled
|
|
|
|
1: eor r1, r1, #3 @ flip Concan access
|
|
mcr p15, 0, r1, c15, c1, 0
|
|
|
|
mrc p15, 0, r1, c2, c0, 0
|
|
sub pc, lr, r1, lsr #32 @ cpwait and return
|
|
|
|
/*
|
|
* Remove Concan ownership of given task
|
|
*
|
|
* r0 = struct thread_info pointer
|
|
*/
|
|
ENTRY(iwmmxt_task_release)
|
|
|
|
mrs r2, cpsr
|
|
orr ip, r2, #PSR_I_BIT @ disable interrupts
|
|
msr cpsr_c, ip
|
|
ldr r3, =concan_owner
|
|
add r0, r0, #TI_IWMMXT_STATE @ get task Concan save area
|
|
ldr r1, [r3] @ get current Concan owner
|
|
eors r0, r0, r1 @ if equal...
|
|
streq r0, [r3] @ then clear ownership
|
|
msr cpsr_c, r2 @ restore interrupts
|
|
mov pc, lr
|
|
|
|
.data
|
|
concan_owner:
|
|
.word 0
|
|
|