/*
* arch/arm/kernel/crunch-bits.S
* Cirrus MaverickCrunch context switching and handling
*
* Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
*
* Shamelessly stolen from the iWMMXt code by Nicolas Pitre, which is
* 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>
#include <mach/ep93xx-regs.h>
/*
* We can't use hex constants here due to a bug in gas.
*/
#define CRUNCH_MVDX0 0
#define CRUNCH_MVDX1 8
#define CRUNCH_MVDX2 16
#define CRUNCH_MVDX3 24
#define CRUNCH_MVDX4 32
#define CRUNCH_MVDX5 40
#define CRUNCH_MVDX6 48
#define CRUNCH_MVDX7 56
#define CRUNCH_MVDX8 64
#define CRUNCH_MVDX9 72
#define CRUNCH_MVDX10 80
#define CRUNCH_MVDX11 88
#define CRUNCH_MVDX12 96
#define CRUNCH_MVDX13 104
#define CRUNCH_MVDX14 112
#define CRUNCH_MVDX15 120
#define CRUNCH_MVAX0L 128
#define CRUNCH_MVAX0M 132
#define CRUNCH_MVAX0H 136
#define CRUNCH_MVAX1L 140
#define CRUNCH_MVAX1M 144
#define CRUNCH_MVAX1H 148
#define CRUNCH_MVAX2L 152
#define CRUNCH_MVAX2M 156
#define CRUNCH_MVAX2H 160
#define CRUNCH_MVAX3L 164
#define CRUNCH_MVAX3M 168
#define CRUNCH_MVAX3H 172
#define CRUNCH_DSPSC 176
#define CRUNCH_SIZE 184
.text
/*
* Lazy switching of crunch coprocessor context
*
* r10 = struct thread_info pointer
* r9 = ret_from_exception
* lr = undefined instr exit
*
* called from prefetch exception handler with interrupts disabled
*/
ENTRY(crunch_task_enable)
ldr r8, =(EP93XX_APB_VIRT_BASE + 0x00130000) @ syscon addr
ldr r1, [r8, #0x80]
tst r1, #0x00800000 @ access to crunch enabled?
movne pc, lr @ if so no business here
mov r3, #0xaa @ unlock syscon swlock
str r3, [r8, #0xc0]
orr r1, r1, #0x00800000 @ enable access to crunch
str r1, [r8, #0x80]
ldr r3, =crunch_owner
add r0, r10, #TI_CRUNCH_STATE @ get task crunch save area
ldr r2, [sp, #60] @ current task pc value
ldr r1, [r3] @ get current crunch owner
str r0, [r3] @ this task now owns crunch
sub r2, r2, #4 @ adjust pc back
str r2, [sp, #60]
ldr r2, [r8, #0x80]
mov r2, r2 @ flush out enable (@@@)
teq r1, #0 @ test for last ownership
mov lr, r9 @ normal exit from exception
beq crunch_load @ no owner, skip save
crunch_save:
cfstr64 mvdx0, [r1, #CRUNCH_MVDX0] @ save 64b registers
cfstr64 mvdx1, [r1, #CRUNCH_MVDX1]
cfstr64 mvdx2, [r1, #CRUNCH_MVDX2]
cfstr64 mvdx3, [r1, #CRUNCH_MVDX3]
cfstr64 mvdx4, [r1, #CRUNCH_MVDX4]
cfstr64 mvdx5, [r1, #CRUNCH_MVDX5]
cfstr64 mvdx6, [r1, #CRUNCH_MVDX6]
cfstr64 mvdx7, [r1, #CRUNCH_MVDX7]
cfstr64 mvdx8, [r1, #CRUNCH_MVDX8]
cfstr64 mvdx9, [r1, #CRUNCH_MVDX9]
cfstr64 mvdx10, [r1, #CRUNCH_MVDX10]
cfstr64 mvdx11, [r1, #CRUNCH_MVDX11]
cfstr64 mvdx12, [r1, #CRUNCH_MVDX12]
cfstr64 mvdx13, [r1, #CRUNCH_MVDX13]
cfstr64 mvdx14, [r1, #CRUNCH_MVDX14]
cfstr64 mvdx15, [r1, #CRUNCH_MVDX15]
#ifdef __ARMEB__
#error fix me for ARMEB
#endif
cfmv32al mvfx0, mvax0 @ save 72b accumulators
cfstr32 mvfx0, [r1, #CRUNCH_MVAX0L]
cfmv32am mvfx0, mvax0
cfstr32 mvfx0, [r1, #CRUNCH_MVAX0M]
cfmv32ah mvfx0, mvax0
cfstr32 mvfx0, [r1, #CRUNCH_MVAX0H]
cfmv32al mvfx0, mvax1
cfstr32 mvfx0, [r1, #CRUNCH_MVAX1L]
cfmv32am mvfx0, mvax1
cfstr32 mvfx0, [r1, #CRUNCH_MVAX1M]
cfmv32ah mvfx0, mvax1
cfstr32 mvfx0, [r1, #CRUNCH_MVAX1H]
cfmv32al mvfx0, mvax2
cfstr32 mvfx0, [r1, #CRUNCH_MVAX2L]
cfmv32am mvfx0, mvax2
cfstr32 mvfx0, [r1, #CRUNCH_MVAX2M]
cfmv32ah mvfx0, mvax2
cfstr32 mvfx0, [r1, #CRUNCH_MVAX2H]
cfmv32al mvfx0, mvax3
cfstr32 mvfx0, [r1, #CRUNCH_MVAX3L]
cfmv32am mvfx0, mvax3
cfstr32 mvfx0, [r1, #CRUNCH_MVAX3M]
cfmv32ah mvfx0, mvax3
cfstr32 mvfx0, [r1, #CRUNCH_MVAX3H]
cfmv32sc mvdx0, dspsc @ save status word
cfstr64 mvdx0, [r1, #CRUNCH_DSPSC]
teq r0, #0 @ anything to load?
cfldr64eq mvdx0, [r1, #CRUNCH_MVDX0] @ mvdx0 was clobbered
moveq pc, lr
crunch_load:
cfldr64 mvdx0, [r0, #CRUNCH_DSPSC] @ load status word
cfmvsc32 dspsc, mvdx0
cfldr32 mvfx0, [r0, #CRUNCH_MVAX0L] @ load 72b accumulators
cfmval32 mvax0, mvfx0
cfldr32 mvfx0, [r0, #CRUNCH_MVAX0M]
cfmvam32 mvax0, mvfx0
cfldr32 mvfx0, [r0, #CRUNCH_MVAX0H]
cfmvah32 mvax0, mvfx0
cfldr32 mvfx0, [r0, #CRUNCH_MVAX1L]
cfmval32 mvax1, mvfx0
cfldr32 mvfx0, [r0, #CRUNCH_MVAX1M]
cfmvam32 mvax1, mvfx0
cfldr32 mvfx0, [r0, #CRUNCH_MVAX1H]
cfmvah32 mvax1, mvfx0
cfldr32 mvfx0, [r0, #CRUNCH_MVAX2L]
cfmval32 mvax2, mvfx0
cfldr32 mvfx0, [r0, #CRUNCH_MVAX2M]
cfmvam32 mvax2, mvfx0
cfldr32 mvfx0, [r0, #CRUNCH_MVAX2H]
cfmvah32 mvax2, mvfx0
cfldr32 mvfx0, [r0, #CRUNCH_MVAX3L]
cfmval32 mvax3, mvfx0
cfldr32 mvfx0, [r0, #CRUNCH_MVAX3M]
cfmvam32 mvax3, mvfx0
cfldr32 mvfx0, [r0, #CRUNCH_MVAX3H]
cfmvah32 mvax3, mvfx0
cfldr64 mvdx0, [r0, #CRUNCH_MVDX0] @ load 64b registers
cfldr64 mvdx1, [r0, #CRUNCH_MVDX1]
cfldr64 mvdx2, [r0, #CRUNCH_MVDX2]
cfldr64 mvdx3, [r0, #CRUNCH_MVDX3]
cfldr64 mvdx4, [r0, #CRUNCH_MVDX4]
cfldr64 mvdx5, [r0, #CRUNCH_MVDX5]
cfldr64 mvdx6, [r0, #CRUNCH_MVDX6]
cfldr64 mvdx7, [r0, #CRUNCH_MVDX7]
cfldr64 mvdx8, [r0, #CRUNCH_MVDX8]
cfldr64 mvdx9, [r0, #CRUNCH_MVDX9]
cfldr64 mvdx10, [r0, #CRUNCH_MVDX10]
cfldr64 mvdx11, [r0, #CRUNCH_MVDX11]
cfldr64 mvdx12, [r0, #CRUNCH_MVDX12]
cfldr64 mvdx13, [r0, #CRUNCH_MVDX13]
cfldr64 mvdx14, [r0, #CRUNCH_MVDX14]
cfldr64 mvdx15, [r0, #CRUNCH_MVDX15]
mov pc, lr
/*
* Back up crunch 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(crunch_task_disable)
stmfd sp!, {r4, r5, lr}
mrs ip, cpsr
orr r2, ip, #PSR_I_BIT @ disable interrupts
msr cpsr_c, r2
ldr r4, =(EP93XX_APB_VIRT_BASE + 0x00130000) @ syscon addr
ldr r3, =crunch_owner
add r2, r0, #TI_CRUNCH_STATE @ get task crunch save area
ldr r1, [r3] @ get current crunch 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
ldr r5, [r4, #0x80] @ enable access to crunch
mov r2, #0xaa
str r2, [r4, #0xc0]
orr r5, r5, #0x00800000
str r5, [r4, #0x80]
mov r0, #0 @ nothing to load
str r0, [r3] @ no more current owner
ldr r2, [r4, #0x80] @ flush out enable (@@@)
mov r2, r2
bl crunch_save
mov r2, #0xaa @ disable access to crunch
str r2, [r4, #0xc0]
bic r5, r5, #0x00800000
str r5, [r4, #0x80]
ldr r5, [r4, #0x80] @ flush out enable (@@@)
mov r5, r5
1: msr cpsr_c, ip @ restore interrupt mode
ldmfd sp!, {r4, r5, pc}
/*
* Copy crunch state to given memory address
*
* r0 = struct thread_info pointer of target task
* r1 = memory address where to store crunch state
*
* this is called mainly in the creation of signal stack frames
*/
ENTRY(crunch_task_copy)
mrs ip, cpsr
orr r2, ip, #PSR_I_BIT @ disable interrupts
msr cpsr_c, r2
ldr r3, =crunch_owner
add r2, r0, #TI_CRUNCH_STATE @ get task crunch save area
ldr r3, [r3] @ get current crunch owner
teq r2, r3 @ does this task own it...
beq 1f
@ current crunch values are in the task save area
msr cpsr_c, ip @ restore interrupt mode
mov r0, r1
mov r1, r2
mov r2, #CRUNCH_SIZE
b memcpy
1: @ this task owns crunch regs -- grab a copy from there
mov r0, #0 @ nothing to load
mov r3, lr @ preserve return address
bl crunch_save
msr cpsr_c, ip @ restore interrupt mode
mov pc, r3
/*
* Restore crunch state from given memory address
*
* r0 = struct thread_info pointer of target task
* r1 = memory address where to get crunch state from
*
* this is used to restore crunch state when unwinding a signal stack frame
*/
ENTRY(crunch_task_restore)
mrs ip, cpsr
orr r2, ip, #PSR_I_BIT @ disable interrupts
msr cpsr_c, r2
ldr r3, =crunch_owner
add r2, r0, #TI_CRUNCH_STATE @ get task crunch save area
ldr r3, [r3] @ get current crunch owner
teq r2, r3 @ does this task own it...
beq 1f
@ this task doesn't own crunch regs -- use its save area
msr cpsr_c, ip @ restore interrupt mode
mov r0, r2
mov r2, #CRUNCH_SIZE
b memcpy
1: @ this task owns crunch regs -- load them directly
mov r0, r1
mov r1, #0 @ nothing to save
mov r3, lr @ preserve return address
bl crunch_load
msr cpsr_c, ip @ restore interrupt mode
mov pc, r3