| /* |
| * 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> |
| |
| /* |
| * For SMTC kernel, global IE should be left set, and interrupts |
| * controlled exclusively via IXMT. |
| */ |
| #ifdef CONFIG_MIPS_MT_SMTC |
| #define STATMASK 0x1e |
| #elif defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) |
| #define STATMASK 0x3f |
| #else |
| #define STATMASK 0x1f |
| #endif |
| |
| #ifdef CONFIG_MIPS_MT_SMTC |
| #include <asm/mipsmtregs.h> |
| #endif /* CONFIG_MIPS_MT_SMTC */ |
| |
| .macro SAVE_AT |
| .set push |
| .set noat |
| LONG_S $1, PT_R1(sp) |
| .set pop |
| .endm |
| |
| .macro SAVE_TEMP |
| #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) |
| #else |
| mfhi v1 |
| #endif |
| #ifdef CONFIG_32BIT |
| LONG_S $8, PT_R8(sp) |
| LONG_S $9, PT_R9(sp) |
| #endif |
| LONG_S $10, PT_R10(sp) |
| LONG_S $11, PT_R11(sp) |
| LONG_S $12, PT_R12(sp) |
| #ifndef CONFIG_CPU_HAS_SMARTMIPS |
| LONG_S v1, PT_HI(sp) |
| mflo v1 |
| #endif |
| LONG_S $13, PT_R13(sp) |
| LONG_S $14, PT_R14(sp) |
| LONG_S $15, PT_R15(sp) |
| LONG_S $24, PT_R24(sp) |
| #ifndef CONFIG_CPU_HAS_SMARTMIPS |
| LONG_S v1, PT_LO(sp) |
| #endif |
| .endm |
| |
| .macro SAVE_STATIC |
| LONG_S $16, PT_R16(sp) |
| LONG_S $17, PT_R17(sp) |
| LONG_S $18, PT_R18(sp) |
| LONG_S $19, PT_R19(sp) |
| LONG_S $20, PT_R20(sp) |
| LONG_S $21, PT_R21(sp) |
| LONG_S $22, PT_R22(sp) |
| LONG_S $23, PT_R23(sp) |
| LONG_S $30, PT_R30(sp) |
| .endm |
| |
| #ifdef CONFIG_SMP |
| #ifdef CONFIG_MIPS_MT_SMTC |
| #define PTEBASE_SHIFT 19 /* TCBIND */ |
| #define CPU_ID_REG CP0_TCBIND |
| #define CPU_ID_MFC0 mfc0 |
| #elif defined(CONFIG_MIPS_PGD_C0_CONTEXT) |
| #define PTEBASE_SHIFT 48 /* XCONTEXT */ |
| #define CPU_ID_REG CP0_XCONTEXT |
| #define CPU_ID_MFC0 MFC0 |
| #else |
| #define PTEBASE_SHIFT 23 /* CONTEXT */ |
| #define CPU_ID_REG CP0_CONTEXT |
| #define CPU_ID_MFC0 MFC0 |
| #endif |
| .macro get_saved_sp /* SMP variation */ |
| CPU_ID_MFC0 k0, CPU_ID_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, PTEBASE_SHIFT |
| LONG_ADDU k1, k0 |
| LONG_L k1, %lo(kernelsp)(k1) |
| .endm |
| |
| .macro set_saved_sp stackp temp temp2 |
| CPU_ID_MFC0 \temp, CPU_ID_REG |
| LONG_SRL \temp, PTEBASE_SHIFT |
| LONG_S \stackp, kernelsp(\temp) |
| .endm |
| #else |
| .macro get_saved_sp /* Uniprocessor variation */ |
| #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_LOONGSON2F */ |
| #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 |
| LONG_L k1, %lo(kernelsp)(k1) |
| .endm |
| |
| .macro set_saved_sp stackp temp temp2 |
| LONG_S \stackp, kernelsp |
| .endm |
| #endif |
| |
| .macro SAVE_SOME |
| .set push |
| .set noat |
| .set reorder |
| mfc0 k0, CP0_STATUS |
| sll k0, 3 /* extract cu0 bit */ |
| .set noreorder |
| bltz k0, 8f |
| move k1, sp |
| .set reorder |
| /* Called from user mode, new stack. */ |
| get_saved_sp |
| #ifndef CONFIG_CPU_DADDI_WORKAROUNDS |
| 8: move k0, sp |
| PTR_SUBU sp, k1, PT_SIZE |
| #else |
| .set at=k0 |
| 8: PTR_SUBU k1, PT_SIZE |
| .set noat |
| move k0, sp |
| move sp, k1 |
| #endif |
| LONG_S k0, PT_R29(sp) |
| LONG_S $3, PT_R3(sp) |
| /* |
| * 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 |
| LONG_S $2, PT_R2(sp) |
| #ifdef CONFIG_MIPS_MT_SMTC |
| /* |
| * Ideally, these instructions would be shuffled in |
| * to cover the pipeline delay. |
| */ |
| .set mips32 |
| mfc0 k0, CP0_TCSTATUS |
| .set mips0 |
| LONG_S k0, PT_TCSTATUS(sp) |
| #endif /* CONFIG_MIPS_MT_SMTC */ |
| LONG_S $4, PT_R4(sp) |
| LONG_S $5, PT_R5(sp) |
| LONG_S v1, PT_STATUS(sp) |
| mfc0 v1, CP0_CAUSE |
| LONG_S $6, PT_R6(sp) |
| LONG_S $7, PT_R7(sp) |
| LONG_S v1, PT_CAUSE(sp) |
| MFC0 v1, CP0_EPC |
| #ifdef CONFIG_64BIT |
| LONG_S $8, PT_R8(sp) |
| LONG_S $9, PT_R9(sp) |
| #endif |
| LONG_S $25, PT_R25(sp) |
| LONG_S $28, PT_R28(sp) |
| LONG_S $31, PT_R31(sp) |
| LONG_S v1, PT_EPC(sp) |
| ori $28, sp, _THREAD_MASK |
| xori $28, _THREAD_MASK |
| #ifdef CONFIG_CPU_CAVIUM_OCTEON |
| .set mips64 |
| pref 0, 0($28) /* Prefetch the current pointer */ |
| pref 0, PT_R31(sp) /* Prefetch the $31(ra) */ |
| /* 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 |
| LONG_L v1, 0($28) /* Load the current pointer */ |
| /* Restore $31(ra) that was changed by the jal */ |
| LONG_L ra, PT_R31(sp) |
| pref 0, 0(v1) /* Prefetch the current thread */ |
| #endif |
| .set pop |
| .endm |
| |
| .macro SAVE_ALL |
| SAVE_SOME |
| SAVE_AT |
| SAVE_TEMP |
| SAVE_STATIC |
| .endm |
| |
| .macro RESTORE_AT |
| .set push |
| .set noat |
| LONG_L $1, PT_R1(sp) |
| .set pop |
| .endm |
| |
| .macro RESTORE_TEMP |
| #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 |
| #else |
| LONG_L $24, PT_LO(sp) |
| mtlo $24 |
| LONG_L $24, PT_HI(sp) |
| mthi $24 |
| #endif |
| #ifdef CONFIG_32BIT |
| LONG_L $8, PT_R8(sp) |
| LONG_L $9, PT_R9(sp) |
| #endif |
| LONG_L $10, PT_R10(sp) |
| LONG_L $11, PT_R11(sp) |
| LONG_L $12, PT_R12(sp) |
| LONG_L $13, PT_R13(sp) |
| LONG_L $14, PT_R14(sp) |
| LONG_L $15, PT_R15(sp) |
| LONG_L $24, PT_R24(sp) |
| .endm |
| |
| .macro RESTORE_STATIC |
| LONG_L $16, PT_R16(sp) |
| LONG_L $17, PT_R17(sp) |
| LONG_L $18, PT_R18(sp) |
| LONG_L $19, PT_R19(sp) |
| LONG_L $20, PT_R20(sp) |
| LONG_L $21, PT_R21(sp) |
| LONG_L $22, PT_R22(sp) |
| LONG_L $23, PT_R23(sp) |
| LONG_L $30, PT_R30(sp) |
| .endm |
| |
| #if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) |
| |
| .macro RESTORE_SOME |
| .set push |
| .set reorder |
| .set noat |
| mfc0 a0, CP0_STATUS |
| li v1, 0xff00 |
| 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 |
| LONG_L $31, PT_R31(sp) |
| LONG_L $28, PT_R28(sp) |
| LONG_L $25, PT_R25(sp) |
| LONG_L $7, PT_R7(sp) |
| LONG_L $6, PT_R6(sp) |
| LONG_L $5, PT_R5(sp) |
| LONG_L $4, PT_R4(sp) |
| LONG_L $3, PT_R3(sp) |
| LONG_L $2, PT_R2(sp) |
| .set pop |
| .endm |
| |
| .macro RESTORE_SP_AND_RET |
| .set push |
| .set noreorder |
| LONG_L k0, PT_EPC(sp) |
| LONG_L sp, PT_R29(sp) |
| jr k0 |
| rfe |
| .set pop |
| .endm |
| |
| #else |
| .macro RESTORE_SOME |
| .set push |
| .set reorder |
| .set noat |
| #ifdef CONFIG_MIPS_MT_SMTC |
| .set mips32r2 |
| /* |
| * We need to make sure the read-modify-write |
| * of Status below isn't perturbed by an interrupt |
| * or cross-TC access, so we need to do at least a DMT, |
| * protected by an interrupt-inhibit. But setting IXMT |
| * also creates a few-cycle window where an IPI could |
| * be queued and not be detected before potentially |
| * returning to a WAIT or user-mode loop. It must be |
| * replayed. |
| * |
| * We're in the middle of a context switch, and |
| * we can't dispatch it directly without trashing |
| * some registers, so we'll try to detect this unlikely |
| * case and program a software interrupt in the VPE, |
| * as would be done for a cross-VPE IPI. To accommodate |
| * the handling of that case, we're doing a DVPE instead |
| * of just a DMT here to protect against other threads. |
| * This is a lot of cruft to cover a tiny window. |
| * If you can find a better design, implement it! |
| * |
| */ |
| mfc0 v0, CP0_TCSTATUS |
| ori v0, TCSTATUS_IXMT |
| mtc0 v0, CP0_TCSTATUS |
| _ehb |
| DVPE 5 # dvpe a1 |
| jal mips_ihb |
| #endif /* CONFIG_MIPS_MT_SMTC */ |
| #ifdef CONFIG_CPU_CAVIUM_OCTEON |
| /* Restore the Octeon multiplier state */ |
| jal octeon_mult_restore |
| #endif |
| mfc0 a0, CP0_STATUS |
| ori a0, STATMASK |
| xori a0, STATMASK |
| mtc0 a0, CP0_STATUS |
| li v1, 0xff00 |
| and a0, v1 |
| LONG_L v0, PT_STATUS(sp) |
| nor v1, $0, v1 |
| and v0, v1 |
| or v0, a0 |
| mtc0 v0, CP0_STATUS |
| #ifdef CONFIG_MIPS_MT_SMTC |
| /* |
| * Only after EXL/ERL have been restored to status can we |
| * restore TCStatus.IXMT. |
| */ |
| LONG_L v1, PT_TCSTATUS(sp) |
| _ehb |
| mfc0 a0, CP0_TCSTATUS |
| andi v1, TCSTATUS_IXMT |
| bnez v1, 0f |
| |
| /* |
| * We'd like to detect any IPIs queued in the tiny window |
| * above and request an software interrupt to service them |
| * when we ERET. |
| * |
| * Computing the offset into the IPIQ array of the executing |
| * TC's IPI queue in-line would be tedious. We use part of |
| * the TCContext register to hold 16 bits of offset that we |
| * can add in-line to find the queue head. |
| */ |
| mfc0 v0, CP0_TCCONTEXT |
| la a2, IPIQ |
| srl v0, v0, 16 |
| addu a2, a2, v0 |
| LONG_L v0, 0(a2) |
| beqz v0, 0f |
| /* |
| * If we have a queue, provoke dispatch within the VPE by setting C_SW1 |
| */ |
| mfc0 v0, CP0_CAUSE |
| ori v0, v0, C_SW1 |
| mtc0 v0, CP0_CAUSE |
| 0: |
| /* |
| * This test should really never branch but |
| * let's be prudent here. Having atomized |
| * the shared register modifications, we can |
| * now EVPE, and must do so before interrupts |
| * are potentially re-enabled. |
| */ |
| andi a1, a1, MVPCONTROL_EVP |
| beqz a1, 1f |
| evpe |
| 1: |
| /* We know that TCStatua.IXMT should be set from above */ |
| xori a0, a0, TCSTATUS_IXMT |
| or a0, a0, v1 |
| mtc0 a0, CP0_TCSTATUS |
| _ehb |
| |
| .set mips0 |
| #endif /* CONFIG_MIPS_MT_SMTC */ |
| LONG_L v1, PT_EPC(sp) |
| MTC0 v1, CP0_EPC |
| LONG_L $31, PT_R31(sp) |
| LONG_L $28, PT_R28(sp) |
| LONG_L $25, PT_R25(sp) |
| #ifdef CONFIG_64BIT |
| LONG_L $8, PT_R8(sp) |
| LONG_L $9, PT_R9(sp) |
| #endif |
| LONG_L $7, PT_R7(sp) |
| LONG_L $6, PT_R6(sp) |
| LONG_L $5, PT_R5(sp) |
| LONG_L $4, PT_R4(sp) |
| LONG_L $3, PT_R3(sp) |
| LONG_L $2, PT_R2(sp) |
| .set pop |
| .endm |
| |
| .macro RESTORE_SP_AND_RET |
| LONG_L sp, PT_R29(sp) |
| .set mips3 |
| eret |
| .set mips0 |
| .endm |
| |
| #endif |
| |
| .macro RESTORE_SP |
| LONG_L sp, PT_R29(sp) |
| .endm |
| |
| .macro RESTORE_ALL |
| RESTORE_TEMP |
| RESTORE_STATIC |
| RESTORE_AT |
| RESTORE_SOME |
| RESTORE_SP |
| .endm |
| |
| .macro RESTORE_ALL_AND_RET |
| RESTORE_TEMP |
| RESTORE_STATIC |
| RESTORE_AT |
| RESTORE_SOME |
| RESTORE_SP_AND_RET |
| .endm |
| |
| /* |
| * Move to kernel mode and disable interrupts. |
| * Set cp0 enable bit as sign that we're running on the kernel stack |
| */ |
| .macro CLI |
| #if !defined(CONFIG_MIPS_MT_SMTC) |
| mfc0 t0, CP0_STATUS |
| li t1, ST0_CU0 | STATMASK |
| or t0, t1 |
| xori t0, STATMASK |
| mtc0 t0, CP0_STATUS |
| #else /* CONFIG_MIPS_MT_SMTC */ |
| /* |
| * For SMTC, we need to set privilege |
| * and disable interrupts only for the |
| * current TC, using the TCStatus register. |
| */ |
| mfc0 t0, CP0_TCSTATUS |
| /* Fortunately CU 0 is in the same place in both registers */ |
| /* Set TCU0, TMX, TKSU (for later inversion) and IXMT */ |
| li t1, ST0_CU0 | 0x08001c00 |
| or t0, t1 |
| /* Clear TKSU, leave IXMT */ |
| xori t0, 0x00001800 |
| mtc0 t0, CP0_TCSTATUS |
| _ehb |
| /* We need to leave the global IE bit set, but clear EXL...*/ |
| mfc0 t0, CP0_STATUS |
| ori t0, ST0_EXL | ST0_ERL |
| xori t0, ST0_EXL | ST0_ERL |
| mtc0 t0, CP0_STATUS |
| #endif /* CONFIG_MIPS_MT_SMTC */ |
| 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 |
| #if !defined(CONFIG_MIPS_MT_SMTC) |
| mfc0 t0, CP0_STATUS |
| li t1, ST0_CU0 | STATMASK |
| or t0, t1 |
| xori t0, STATMASK & ~1 |
| mtc0 t0, CP0_STATUS |
| #else /* CONFIG_MIPS_MT_SMTC */ |
| /* |
| * For SMTC, we need to set privilege |
| * and enable interrupts only for the |
| * current TC, using the TCStatus register. |
| */ |
| _ehb |
| mfc0 t0, CP0_TCSTATUS |
| /* Fortunately CU 0 is in the same place in both registers */ |
| /* Set TCU0, TKSU (for later inversion) and IXMT */ |
| li t1, ST0_CU0 | 0x08001c00 |
| or t0, t1 |
| /* Clear TKSU *and* IXMT */ |
| xori t0, 0x00001c00 |
| mtc0 t0, CP0_TCSTATUS |
| _ehb |
| /* We need to leave the global IE bit set, but clear EXL...*/ |
| mfc0 t0, CP0_STATUS |
| ori t0, ST0_EXL |
| xori t0, ST0_EXL |
| mtc0 t0, CP0_STATUS |
| /* irq_enable_hazard below should expand to EHB for 24K/34K cpus */ |
| #endif /* CONFIG_MIPS_MT_SMTC */ |
| 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 |
| #ifdef CONFIG_MIPS_MT_SMTC |
| /* |
| * This gets baroque in SMTC. We want to |
| * protect the non-atomic clearing of EXL |
| * with DMT/EMT, but we don't want to take |
| * an interrupt while DMT is still in effect. |
| */ |
| |
| /* KMODE gets invoked from both reorder and noreorder code */ |
| .set push |
| .set mips32r2 |
| .set noreorder |
| mfc0 v0, CP0_TCSTATUS |
| andi v1, v0, TCSTATUS_IXMT |
| ori v0, TCSTATUS_IXMT |
| mtc0 v0, CP0_TCSTATUS |
| _ehb |
| DMT 2 # dmt v0 |
| /* |
| * We don't know a priori if ra is "live" |
| */ |
| move t0, ra |
| jal mips_ihb |
| nop /* delay slot */ |
| move ra, t0 |
| #endif /* CONFIG_MIPS_MT_SMTC */ |
| 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 |
| #ifdef CONFIG_MIPS_MT_SMTC |
| _ehb |
| andi v0, v0, VPECONTROL_TE |
| beqz v0, 2f |
| nop /* delay slot */ |
| emt |
| 2: |
| mfc0 v0, CP0_TCSTATUS |
| /* Clear IXMT, then OR in previous value */ |
| ori v0, TCSTATUS_IXMT |
| xori v0, TCSTATUS_IXMT |
| or v0, v1, v0 |
| mtc0 v0, CP0_TCSTATUS |
| /* |
| * irq_disable_hazard below should expand to EHB |
| * on 24K/34K CPUS |
| */ |
| .set pop |
| #endif /* CONFIG_MIPS_MT_SMTC */ |
| irq_disable_hazard |
| .endm |
| |
| #endif /* _ASM_STACKFRAME_H */ |