/* * 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 #include #include #include #include #include /* 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 #ifdef 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_CU0 | 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_CU0 | 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_CU0 | (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 */