diff options
Diffstat (limited to 'arch/mips/include/asm/stackframe.h')
| -rw-r--r-- | arch/mips/include/asm/stackframe.h | 196 |
1 files changed, 1 insertions, 195 deletions
diff --git a/arch/mips/include/asm/stackframe.h b/arch/mips/include/asm/stackframe.h index d301e108d5b..b188c797565 100644 --- a/arch/mips/include/asm/stackframe.h +++ b/arch/mips/include/asm/stackframe.h @@ -19,22 +19,12 @@ #include <asm/asm-offsets.h> #include <asm/thread_info.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) +#if 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 @@ -186,16 +176,6 @@ mfc0 v1, CP0_STATUS LONG_S $2, PT_R2(sp) LONG_S v1, PT_STATUS(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) mfc0 v1, CP0_CAUSE LONG_S $5, PT_R5(sp) @@ -321,36 +301,6 @@ .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 */ mfc0 a0, CP0_STATUS ori a0, STATMASK xori a0, STATMASK @@ -362,59 +312,6 @@ 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) @@ -467,33 +364,11 @@ * 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 @@ -502,35 +377,11 @@ * 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 @@ -540,32 +391,6 @@ * 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) @@ -576,25 +401,6 @@ 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 |