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Diffstat (limited to 'arch/mips/include/asm/stackframe.h')
| -rw-r--r-- | arch/mips/include/asm/stackframe.h | 492 |
1 files changed, 492 insertions, 0 deletions
diff --git a/arch/mips/include/asm/stackframe.h b/arch/mips/include/asm/stackframe.h new file mode 100644 index 000000000..aa430a6c6 --- /dev/null +++ b/arch/mips/include/asm/stackframe.h @@ -0,0 +1,492 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 1994, 95, 96, 99, 2001 Ralf Baechle + * Copyright (C) 1994, 1995, 1996 Paul M. Antoine. + * Copyright (C) 1999 Silicon Graphics, Inc. + * Copyright (C) 2007 Maciej W. Rozycki + */ +#ifndef _ASM_STACKFRAME_H +#define _ASM_STACKFRAME_H + +#include <linux/threads.h> + +#include <asm/asm.h> +#include <asm/asmmacro.h> +#include <asm/mipsregs.h> +#include <asm/asm-offsets.h> +#include <asm/thread_info.h> + +/* Make the addition of cfi info a little easier. */ + .macro cfi_rel_offset reg offset=0 docfi=0 + .if \docfi + .cfi_rel_offset \reg, \offset + .endif + .endm + + .macro cfi_st reg offset=0 docfi=0 + LONG_S \reg, \offset(sp) + cfi_rel_offset \reg, \offset, \docfi + .endm + + .macro cfi_restore reg offset=0 docfi=0 + .if \docfi + .cfi_restore \reg + .endif + .endm + + .macro cfi_ld reg offset=0 docfi=0 + LONG_L \reg, \offset(sp) + cfi_restore \reg \offset \docfi + .endm + +#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) +#define STATMASK 0x3f +#else +#define STATMASK 0x1f +#endif + + .macro SAVE_AT docfi=0 + .set push + .set noat + cfi_st $1, PT_R1, \docfi + .set pop + .endm + + .macro SAVE_TEMP docfi=0 +#ifdef CONFIG_CPU_HAS_SMARTMIPS + mflhxu v1 + LONG_S v1, PT_LO(sp) + mflhxu v1 + LONG_S v1, PT_HI(sp) + mflhxu v1 + LONG_S v1, PT_ACX(sp) +#elif !defined(CONFIG_CPU_MIPSR6) + mfhi v1 +#endif +#ifdef CONFIG_32BIT + cfi_st $8, PT_R8, \docfi + cfi_st $9, PT_R9, \docfi +#endif + cfi_st $10, PT_R10, \docfi + cfi_st $11, PT_R11, \docfi + cfi_st $12, PT_R12, \docfi +#if !defined(CONFIG_CPU_HAS_SMARTMIPS) && !defined(CONFIG_CPU_MIPSR6) + LONG_S v1, PT_HI(sp) + mflo v1 +#endif + cfi_st $13, PT_R13, \docfi + cfi_st $14, PT_R14, \docfi + cfi_st $15, PT_R15, \docfi + cfi_st $24, PT_R24, \docfi +#if !defined(CONFIG_CPU_HAS_SMARTMIPS) && !defined(CONFIG_CPU_MIPSR6) + LONG_S v1, PT_LO(sp) +#endif +#ifdef CONFIG_CPU_CAVIUM_OCTEON + /* + * The Octeon multiplier state is affected by general + * multiply instructions. It must be saved before and + * kernel code might corrupt it + */ + jal octeon_mult_save +#endif + .endm + + .macro SAVE_STATIC docfi=0 + cfi_st $16, PT_R16, \docfi + cfi_st $17, PT_R17, \docfi + cfi_st $18, PT_R18, \docfi + cfi_st $19, PT_R19, \docfi + cfi_st $20, PT_R20, \docfi + cfi_st $21, PT_R21, \docfi + cfi_st $22, PT_R22, \docfi + cfi_st $23, PT_R23, \docfi + cfi_st $30, PT_R30, \docfi + .endm + +/* + * get_saved_sp returns the SP for the current CPU by looking in the + * kernelsp array for it. If tosp is set, it stores the current sp in + * k0 and loads the new value in sp. If not, it clobbers k0 and + * stores the new value in k1, leaving sp unaffected. + */ +#ifdef CONFIG_SMP + + /* SMP variation */ + .macro get_saved_sp docfi=0 tosp=0 + ASM_CPUID_MFC0 k0, ASM_SMP_CPUID_REG +#if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32) + lui k1, %hi(kernelsp) +#else + lui k1, %highest(kernelsp) + daddiu k1, %higher(kernelsp) + dsll k1, 16 + daddiu k1, %hi(kernelsp) + dsll k1, 16 +#endif + LONG_SRL k0, SMP_CPUID_PTRSHIFT + LONG_ADDU k1, k0 + .if \tosp + move k0, sp + .if \docfi + .cfi_register sp, k0 + .endif + LONG_L sp, %lo(kernelsp)(k1) + .else + LONG_L k1, %lo(kernelsp)(k1) + .endif + .endm + + .macro set_saved_sp stackp temp temp2 + ASM_CPUID_MFC0 \temp, ASM_SMP_CPUID_REG + LONG_SRL \temp, SMP_CPUID_PTRSHIFT + LONG_S \stackp, kernelsp(\temp) + .endm +#else /* !CONFIG_SMP */ + /* Uniprocessor variation */ + .macro get_saved_sp docfi=0 tosp=0 +#ifdef CONFIG_CPU_JUMP_WORKAROUNDS + /* + * Clear BTB (branch target buffer), forbid RAS (return address + * stack) to workaround the Out-of-order Issue in Loongson2F + * via its diagnostic register. + */ + move k0, ra + jal 1f + nop +1: jal 1f + nop +1: jal 1f + nop +1: jal 1f + nop +1: move ra, k0 + li k0, 3 + mtc0 k0, $22 +#endif /* CONFIG_CPU_JUMP_WORKAROUNDS */ +#if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32) + lui k1, %hi(kernelsp) +#else + lui k1, %highest(kernelsp) + daddiu k1, %higher(kernelsp) + dsll k1, k1, 16 + daddiu k1, %hi(kernelsp) + dsll k1, k1, 16 +#endif + .if \tosp + move k0, sp + .if \docfi + .cfi_register sp, k0 + .endif + LONG_L sp, %lo(kernelsp)(k1) + .else + LONG_L k1, %lo(kernelsp)(k1) + .endif + .endm + + .macro set_saved_sp stackp temp temp2 + LONG_S \stackp, kernelsp + .endm +#endif + + .macro SAVE_SOME docfi=0 + .set push + .set noat + .set reorder + mfc0 k0, CP0_STATUS + sll k0, 3 /* extract cu0 bit */ + .set noreorder + bltz k0, 8f + move k0, sp + .if \docfi + .cfi_register sp, k0 + .endif +#ifdef CONFIG_EVA + /* + * Flush interAptiv's Return Prediction Stack (RPS) by writing + * EntryHi. Toggling Config7.RPS is slower and less portable. + * + * The RPS isn't automatically flushed when exceptions are + * taken, which can result in kernel mode speculative accesses + * to user addresses if the RPS mispredicts. That's harmless + * when user and kernel share the same address space, but with + * EVA the same user segments may be unmapped to kernel mode, + * even containing sensitive MMIO regions or invalid memory. + * + * This can happen when the kernel sets the return address to + * ret_from_* and jr's to the exception handler, which looks + * more like a tail call than a function call. If nested calls + * don't evict the last user address in the RPS, it will + * mispredict the return and fetch from a user controlled + * address into the icache. + * + * More recent EVA-capable cores with MAAR to restrict + * speculative accesses aren't affected. + */ + MFC0 k0, CP0_ENTRYHI + MTC0 k0, CP0_ENTRYHI +#endif + .set reorder + /* Called from user mode, new stack. */ + get_saved_sp docfi=\docfi tosp=1 +8: +#ifdef CONFIG_CPU_DADDI_WORKAROUNDS + .set at=k1 +#endif + PTR_SUBU sp, PT_SIZE +#ifdef CONFIG_CPU_DADDI_WORKAROUNDS + .set noat +#endif + .if \docfi + .cfi_def_cfa sp,0 + .endif + cfi_st k0, PT_R29, \docfi + cfi_rel_offset sp, PT_R29, \docfi + cfi_st v1, PT_R3, \docfi + /* + * You might think that you don't need to save $0, + * but the FPU emulator and gdb remote debug stub + * need it to operate correctly + */ + LONG_S $0, PT_R0(sp) + mfc0 v1, CP0_STATUS + cfi_st v0, PT_R2, \docfi + LONG_S v1, PT_STATUS(sp) + cfi_st $4, PT_R4, \docfi + mfc0 v1, CP0_CAUSE + cfi_st $5, PT_R5, \docfi + LONG_S v1, PT_CAUSE(sp) + cfi_st $6, PT_R6, \docfi + cfi_st ra, PT_R31, \docfi + MFC0 ra, CP0_EPC + cfi_st $7, PT_R7, \docfi +#ifdef CONFIG_64BIT + cfi_st $8, PT_R8, \docfi + cfi_st $9, PT_R9, \docfi +#endif + LONG_S ra, PT_EPC(sp) + .if \docfi + .cfi_rel_offset ra, PT_EPC + .endif + cfi_st $25, PT_R25, \docfi + cfi_st $28, PT_R28, \docfi + + /* Set thread_info if we're coming from user mode */ + mfc0 k0, CP0_STATUS + sll k0, 3 /* extract cu0 bit */ + bltz k0, 9f + + ori $28, sp, _THREAD_MASK + xori $28, _THREAD_MASK +#ifdef CONFIG_CPU_CAVIUM_OCTEON + .set mips64 + pref 0, 0($28) /* Prefetch the current pointer */ +#endif +9: + .set pop + .endm + + .macro SAVE_ALL docfi=0 + SAVE_SOME \docfi + SAVE_AT \docfi + SAVE_TEMP \docfi + SAVE_STATIC \docfi + .endm + + .macro RESTORE_AT docfi=0 + .set push + .set noat + cfi_ld $1, PT_R1, \docfi + .set pop + .endm + + .macro RESTORE_TEMP docfi=0 +#ifdef CONFIG_CPU_CAVIUM_OCTEON + /* Restore the Octeon multiplier state */ + jal octeon_mult_restore +#endif +#ifdef CONFIG_CPU_HAS_SMARTMIPS + LONG_L $24, PT_ACX(sp) + mtlhx $24 + LONG_L $24, PT_HI(sp) + mtlhx $24 + LONG_L $24, PT_LO(sp) + mtlhx $24 +#elif !defined(CONFIG_CPU_MIPSR6) + LONG_L $24, PT_LO(sp) + mtlo $24 + LONG_L $24, PT_HI(sp) + mthi $24 +#endif +#ifdef CONFIG_32BIT + cfi_ld $8, PT_R8, \docfi + cfi_ld $9, PT_R9, \docfi +#endif + cfi_ld $10, PT_R10, \docfi + cfi_ld $11, PT_R11, \docfi + cfi_ld $12, PT_R12, \docfi + cfi_ld $13, PT_R13, \docfi + cfi_ld $14, PT_R14, \docfi + cfi_ld $15, PT_R15, \docfi + cfi_ld $24, PT_R24, \docfi + .endm + + .macro RESTORE_STATIC docfi=0 + cfi_ld $16, PT_R16, \docfi + cfi_ld $17, PT_R17, \docfi + cfi_ld $18, PT_R18, \docfi + cfi_ld $19, PT_R19, \docfi + cfi_ld $20, PT_R20, \docfi + cfi_ld $21, PT_R21, \docfi + cfi_ld $22, PT_R22, \docfi + cfi_ld $23, PT_R23, \docfi + cfi_ld $30, PT_R30, \docfi + .endm + + .macro RESTORE_SP docfi=0 + cfi_ld sp, PT_R29, \docfi + .endm + +#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) + + .macro RESTORE_SOME docfi=0 + .set push + .set reorder + .set noat + mfc0 a0, CP0_STATUS + li v1, ST0_CU1 | ST0_IM + ori a0, STATMASK + xori a0, STATMASK + mtc0 a0, CP0_STATUS + and a0, v1 + LONG_L v0, PT_STATUS(sp) + nor v1, $0, v1 + and v0, v1 + or v0, a0 + mtc0 v0, CP0_STATUS + cfi_ld $31, PT_R31, \docfi + cfi_ld $28, PT_R28, \docfi + cfi_ld $25, PT_R25, \docfi + cfi_ld $7, PT_R7, \docfi + cfi_ld $6, PT_R6, \docfi + cfi_ld $5, PT_R5, \docfi + cfi_ld $4, PT_R4, \docfi + cfi_ld $3, PT_R3, \docfi + cfi_ld $2, PT_R2, \docfi + .set pop + .endm + + .macro RESTORE_SP_AND_RET docfi=0 + .set push + .set noreorder + LONG_L k0, PT_EPC(sp) + RESTORE_SP \docfi + jr k0 + rfe + .set pop + .endm + +#else + .macro RESTORE_SOME docfi=0 + .set push + .set reorder + .set noat + mfc0 a0, CP0_STATUS + ori a0, STATMASK + xori a0, STATMASK + mtc0 a0, CP0_STATUS + li v1, ST0_CU1 | ST0_FR | ST0_IM + and a0, v1 + LONG_L v0, PT_STATUS(sp) + nor v1, $0, v1 + and v0, v1 + or v0, a0 + mtc0 v0, CP0_STATUS + LONG_L v1, PT_EPC(sp) + MTC0 v1, CP0_EPC + cfi_ld $31, PT_R31, \docfi + cfi_ld $28, PT_R28, \docfi + cfi_ld $25, PT_R25, \docfi +#ifdef CONFIG_64BIT + cfi_ld $8, PT_R8, \docfi + cfi_ld $9, PT_R9, \docfi +#endif + cfi_ld $7, PT_R7, \docfi + cfi_ld $6, PT_R6, \docfi + cfi_ld $5, PT_R5, \docfi + cfi_ld $4, PT_R4, \docfi + cfi_ld $3, PT_R3, \docfi + cfi_ld $2, PT_R2, \docfi + .set pop + .endm + + .macro RESTORE_SP_AND_RET docfi=0 + RESTORE_SP \docfi +#if defined(CONFIG_CPU_MIPSR5) || defined(CONFIG_CPU_MIPSR6) + eretnc +#else + .set push + .set arch=r4000 + eret + .set pop +#endif + .endm + +#endif + + .macro RESTORE_ALL docfi=0 + RESTORE_TEMP \docfi + RESTORE_STATIC \docfi + RESTORE_AT \docfi + RESTORE_SOME \docfi + RESTORE_SP \docfi + .endm + +/* + * Move to kernel mode and disable interrupts. + * Set cp0 enable bit as sign that we're running on the kernel stack + */ + .macro CLI + mfc0 t0, CP0_STATUS + li t1, ST0_KERNEL_CUMASK | STATMASK + or t0, t1 + xori t0, STATMASK + mtc0 t0, CP0_STATUS + irq_disable_hazard + .endm + +/* + * Move to kernel mode and enable interrupts. + * Set cp0 enable bit as sign that we're running on the kernel stack + */ + .macro STI + mfc0 t0, CP0_STATUS + li t1, ST0_KERNEL_CUMASK | STATMASK + or t0, t1 + xori t0, STATMASK & ~1 + mtc0 t0, CP0_STATUS + irq_enable_hazard + .endm + +/* + * Just move to kernel mode and leave interrupts as they are. Note + * for the R3000 this means copying the previous enable from IEp. + * Set cp0 enable bit as sign that we're running on the kernel stack + */ + .macro KMODE + mfc0 t0, CP0_STATUS + li t1, ST0_KERNEL_CUMASK | (STATMASK & ~1) +#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) + andi t2, t0, ST0_IEP + srl t2, 2 + or t0, t2 +#endif + or t0, t1 + xori t0, STATMASK & ~1 + mtc0 t0, CP0_STATUS + irq_disable_hazard + .endm + +#endif /* _ASM_STACKFRAME_H */ |