diff options
Diffstat (limited to 'kernel/arch/arm/mach-ep93xx/crunch-bits.S')
| -rw-r--r-- | kernel/arch/arm/mach-ep93xx/crunch-bits.S | 313 |
1 files changed, 313 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-ep93xx/crunch-bits.S b/kernel/arch/arm/mach-ep93xx/crunch-bits.S new file mode 100644 index 000000000..ee0be2af5 --- /dev/null +++ b/kernel/arch/arm/mach-ep93xx/crunch-bits.S @@ -0,0 +1,313 @@ +/* + * 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 <asm/assembler.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 enabled + */ +ENTRY(crunch_task_enable) + inc_preempt_count r10, r3 + + ldr r8, =(EP93XX_APB_VIRT_BASE + 0x00130000) @ syscon addr + + ldr r1, [r8, #0x80] + tst r1, #0x00800000 @ access to crunch enabled? + bne 2f @ 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 + beq 1f + +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] + +1: +#ifdef CONFIG_PREEMPT_COUNT + get_thread_info r10 +#endif +2: dec_preempt_count r10, r3 + ret 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 + ret 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 + ret r3 |