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v3.5.6
  1/*
  2 * Switch a MMU context.
  3 *
  4 * This file is subject to the terms and conditions of the GNU General Public
  5 * License.  See the file "COPYING" in the main directory of this archive
  6 * for more details.
  7 *
  8 * Copyright (C) 1996, 1997, 1998, 1999 by Ralf Baechle
  9 * Copyright (C) 1999 Silicon Graphics, Inc.
 10 */
 11#ifndef _ASM_MMU_CONTEXT_H
 12#define _ASM_MMU_CONTEXT_H
 13
 14#include <linux/errno.h>
 15#include <linux/sched.h>
 16#include <linux/smp.h>
 17#include <linux/slab.h>
 18#include <asm/cacheflush.h>
 19#include <asm/hazards.h>
 20#include <asm/tlbflush.h>
 21#ifdef CONFIG_MIPS_MT_SMTC
 22#include <asm/mipsmtregs.h>
 23#include <asm/smtc.h>
 24#endif /* SMTC */
 25#include <asm-generic/mm_hooks.h>
 26
 27#ifdef CONFIG_MIPS_PGD_C0_CONTEXT
 28
 29#define TLBMISS_HANDLER_SETUP_PGD(pgd)				\
 30	tlbmiss_handler_setup_pgd((unsigned long)(pgd))
 31
 32extern void tlbmiss_handler_setup_pgd(unsigned long pgd);
 33
 34#define TLBMISS_HANDLER_SETUP()						\
 35	do {								\
 36		TLBMISS_HANDLER_SETUP_PGD(swapper_pg_dir);		\
 37		write_c0_xcontext((unsigned long) smp_processor_id() << 51); \
 38	} while (0)
 39
 
 
 
 
 
 
 40#else /* CONFIG_MIPS_PGD_C0_CONTEXT: using  pgd_current*/
 41
 42/*
 43 * For the fast tlb miss handlers, we keep a per cpu array of pointers
 44 * to the current pgd for each processor. Also, the proc. id is stuffed
 45 * into the context register.
 46 */
 47extern unsigned long pgd_current[];
 48
 49#define TLBMISS_HANDLER_SETUP_PGD(pgd) \
 50	pgd_current[smp_processor_id()] = (unsigned long)(pgd)
 51
 52#ifdef CONFIG_32BIT
 53#define TLBMISS_HANDLER_SETUP()						\
 54	write_c0_context((unsigned long) smp_processor_id() << 25);	\
 55	back_to_back_c0_hazard();					\
 56	TLBMISS_HANDLER_SETUP_PGD(swapper_pg_dir)
 57#endif
 58#ifdef CONFIG_64BIT
 59#define TLBMISS_HANDLER_SETUP()						\
 60	write_c0_context((unsigned long) smp_processor_id() << 26);	\
 61	back_to_back_c0_hazard();					\
 62	TLBMISS_HANDLER_SETUP_PGD(swapper_pg_dir)
 63#endif
 64#endif /* CONFIG_MIPS_PGD_C0_CONTEXT*/
 65#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
 66
 67#define ASID_INC	0x40
 68#define ASID_MASK	0xfc0
 69
 70#elif defined(CONFIG_CPU_R8000)
 71
 72#define ASID_INC	0x10
 73#define ASID_MASK	0xff0
 74
 75#elif defined(CONFIG_CPU_RM9000)
 76
 77#define ASID_INC	0x1
 78#define ASID_MASK	0xfff
 79
 80/* SMTC/34K debug hack - but maybe we'll keep it */
 81#elif defined(CONFIG_MIPS_MT_SMTC)
 82
 83#define ASID_INC	0x1
 84extern unsigned long smtc_asid_mask;
 85#define ASID_MASK	(smtc_asid_mask)
 86#define	HW_ASID_MASK	0xff
 87/* End SMTC/34K debug hack */
 88#else /* FIXME: not correct for R6000 */
 89
 90#define ASID_INC	0x1
 91#define ASID_MASK	0xff
 92
 93#endif
 94
 95#define cpu_context(cpu, mm)	((mm)->context.asid[cpu])
 96#define cpu_asid(cpu, mm)	(cpu_context((cpu), (mm)) & ASID_MASK)
 97#define asid_cache(cpu)		(cpu_data[cpu].asid_cache)
 98
 99static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
100{
101}
102
103/*
104 *  All unused by hardware upper bits will be considered
105 *  as a software asid extension.
106 */
107#define ASID_VERSION_MASK  ((unsigned long)~(ASID_MASK|(ASID_MASK-1)))
108#define ASID_FIRST_VERSION ((unsigned long)(~ASID_VERSION_MASK) + 1)
109
110#ifndef CONFIG_MIPS_MT_SMTC
111/* Normal, classic MIPS get_new_mmu_context */
112static inline void
113get_new_mmu_context(struct mm_struct *mm, unsigned long cpu)
114{
115	unsigned long asid = asid_cache(cpu);
116
117	if (! ((asid += ASID_INC) & ASID_MASK) ) {
118		if (cpu_has_vtag_icache)
119			flush_icache_all();
120		local_flush_tlb_all();	/* start new asid cycle */
121		if (!asid)		/* fix version if needed */
122			asid = ASID_FIRST_VERSION;
123	}
124	cpu_context(cpu, mm) = asid_cache(cpu) = asid;
125}
126
127#else /* CONFIG_MIPS_MT_SMTC */
128
129#define get_new_mmu_context(mm, cpu) smtc_get_new_mmu_context((mm), (cpu))
130
131#endif /* CONFIG_MIPS_MT_SMTC */
132
133/*
134 * Initialize the context related info for a new mm_struct
135 * instance.
136 */
137static inline int
138init_new_context(struct task_struct *tsk, struct mm_struct *mm)
139{
140	int i;
141
142	for_each_online_cpu(i)
143		cpu_context(i, mm) = 0;
144
145	return 0;
146}
147
148static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
149                             struct task_struct *tsk)
150{
151	unsigned int cpu = smp_processor_id();
152	unsigned long flags;
153#ifdef CONFIG_MIPS_MT_SMTC
154	unsigned long oldasid;
155	unsigned long mtflags;
156	int mytlb = (smtc_status & SMTC_TLB_SHARED) ? 0 : cpu_data[cpu].vpe_id;
157	local_irq_save(flags);
158	mtflags = dvpe();
159#else /* Not SMTC */
160	local_irq_save(flags);
161#endif /* CONFIG_MIPS_MT_SMTC */
162
163	/* Check if our ASID is of an older version and thus invalid */
164	if ((cpu_context(cpu, next) ^ asid_cache(cpu)) & ASID_VERSION_MASK)
165		get_new_mmu_context(next, cpu);
166#ifdef CONFIG_MIPS_MT_SMTC
167	/*
168	 * If the EntryHi ASID being replaced happens to be
169	 * the value flagged at ASID recycling time as having
170	 * an extended life, clear the bit showing it being
171	 * in use by this "CPU", and if that's the last bit,
172	 * free up the ASID value for use and flush any old
173	 * instances of it from the TLB.
174	 */
175	oldasid = (read_c0_entryhi() & ASID_MASK);
176	if(smtc_live_asid[mytlb][oldasid]) {
177		smtc_live_asid[mytlb][oldasid] &= ~(0x1 << cpu);
178		if(smtc_live_asid[mytlb][oldasid] == 0)
179			smtc_flush_tlb_asid(oldasid);
180	}
181	/*
182	 * Tread softly on EntryHi, and so long as we support
183	 * having ASID_MASK smaller than the hardware maximum,
184	 * make sure no "soft" bits become "hard"...
185	 */
186	write_c0_entryhi((read_c0_entryhi() & ~HW_ASID_MASK) |
187			 cpu_asid(cpu, next));
188	ehb(); /* Make sure it propagates to TCStatus */
189	evpe(mtflags);
190#else
191	write_c0_entryhi(cpu_asid(cpu, next));
192#endif /* CONFIG_MIPS_MT_SMTC */
193	TLBMISS_HANDLER_SETUP_PGD(next->pgd);
194
195	/*
196	 * Mark current->active_mm as not "active" anymore.
197	 * We don't want to mislead possible IPI tlb flush routines.
198	 */
199	cpumask_clear_cpu(cpu, mm_cpumask(prev));
200	cpumask_set_cpu(cpu, mm_cpumask(next));
201
202	local_irq_restore(flags);
203}
204
205/*
206 * Destroy context related info for an mm_struct that is about
207 * to be put to rest.
208 */
209static inline void destroy_context(struct mm_struct *mm)
210{
211}
212
213#define deactivate_mm(tsk, mm)	do { } while (0)
214
215/*
216 * After we have set current->mm to a new value, this activates
217 * the context for the new mm so we see the new mappings.
218 */
219static inline void
220activate_mm(struct mm_struct *prev, struct mm_struct *next)
221{
222	unsigned long flags;
223	unsigned int cpu = smp_processor_id();
224
225#ifdef CONFIG_MIPS_MT_SMTC
226	unsigned long oldasid;
227	unsigned long mtflags;
228	int mytlb = (smtc_status & SMTC_TLB_SHARED) ? 0 : cpu_data[cpu].vpe_id;
229#endif /* CONFIG_MIPS_MT_SMTC */
230
231	local_irq_save(flags);
232
233	/* Unconditionally get a new ASID.  */
234	get_new_mmu_context(next, cpu);
235
236#ifdef CONFIG_MIPS_MT_SMTC
237	/* See comments for similar code above */
238	mtflags = dvpe();
239	oldasid = read_c0_entryhi() & ASID_MASK;
240	if(smtc_live_asid[mytlb][oldasid]) {
241		smtc_live_asid[mytlb][oldasid] &= ~(0x1 << cpu);
242		if(smtc_live_asid[mytlb][oldasid] == 0)
243			 smtc_flush_tlb_asid(oldasid);
244	}
245	/* See comments for similar code above */
246	write_c0_entryhi((read_c0_entryhi() & ~HW_ASID_MASK) |
247	                 cpu_asid(cpu, next));
248	ehb(); /* Make sure it propagates to TCStatus */
249	evpe(mtflags);
250#else
251	write_c0_entryhi(cpu_asid(cpu, next));
252#endif /* CONFIG_MIPS_MT_SMTC */
253	TLBMISS_HANDLER_SETUP_PGD(next->pgd);
254
255	/* mark mmu ownership change */
256	cpumask_clear_cpu(cpu, mm_cpumask(prev));
257	cpumask_set_cpu(cpu, mm_cpumask(next));
258
259	local_irq_restore(flags);
260}
261
262/*
263 * If mm is currently active_mm, we can't really drop it.  Instead,
264 * we will get a new one for it.
265 */
266static inline void
267drop_mmu_context(struct mm_struct *mm, unsigned cpu)
268{
269	unsigned long flags;
270#ifdef CONFIG_MIPS_MT_SMTC
271	unsigned long oldasid;
272	/* Can't use spinlock because called from TLB flush within DVPE */
273	unsigned int prevvpe;
274	int mytlb = (smtc_status & SMTC_TLB_SHARED) ? 0 : cpu_data[cpu].vpe_id;
275#endif /* CONFIG_MIPS_MT_SMTC */
276
277	local_irq_save(flags);
278
279	if (cpumask_test_cpu(cpu, mm_cpumask(mm)))  {
280		get_new_mmu_context(mm, cpu);
281#ifdef CONFIG_MIPS_MT_SMTC
282		/* See comments for similar code above */
283		prevvpe = dvpe();
284		oldasid = (read_c0_entryhi() & ASID_MASK);
285		if (smtc_live_asid[mytlb][oldasid]) {
286			smtc_live_asid[mytlb][oldasid] &= ~(0x1 << cpu);
287			if(smtc_live_asid[mytlb][oldasid] == 0)
288				smtc_flush_tlb_asid(oldasid);
289		}
290		/* See comments for similar code above */
291		write_c0_entryhi((read_c0_entryhi() & ~HW_ASID_MASK)
292				| cpu_asid(cpu, mm));
293		ehb(); /* Make sure it propagates to TCStatus */
294		evpe(prevvpe);
295#else /* not CONFIG_MIPS_MT_SMTC */
296		write_c0_entryhi(cpu_asid(cpu, mm));
297#endif /* CONFIG_MIPS_MT_SMTC */
298	} else {
299		/* will get a new context next time */
300#ifndef CONFIG_MIPS_MT_SMTC
301		cpu_context(cpu, mm) = 0;
302#else /* SMTC */
303		int i;
304
305		/* SMTC shares the TLB (and ASIDs) across VPEs */
306		for_each_online_cpu(i) {
307		    if((smtc_status & SMTC_TLB_SHARED)
308		    || (cpu_data[i].vpe_id == cpu_data[cpu].vpe_id))
309			cpu_context(i, mm) = 0;
310		}
311#endif /* CONFIG_MIPS_MT_SMTC */
312	}
313	local_irq_restore(flags);
314}
315
316#endif /* _ASM_MMU_CONTEXT_H */
v3.1
  1/*
  2 * Switch a MMU context.
  3 *
  4 * This file is subject to the terms and conditions of the GNU General Public
  5 * License.  See the file "COPYING" in the main directory of this archive
  6 * for more details.
  7 *
  8 * Copyright (C) 1996, 1997, 1998, 1999 by Ralf Baechle
  9 * Copyright (C) 1999 Silicon Graphics, Inc.
 10 */
 11#ifndef _ASM_MMU_CONTEXT_H
 12#define _ASM_MMU_CONTEXT_H
 13
 14#include <linux/errno.h>
 15#include <linux/sched.h>
 16#include <linux/smp.h>
 17#include <linux/slab.h>
 18#include <asm/cacheflush.h>
 19#include <asm/hazards.h>
 20#include <asm/tlbflush.h>
 21#ifdef CONFIG_MIPS_MT_SMTC
 22#include <asm/mipsmtregs.h>
 23#include <asm/smtc.h>
 24#endif /* SMTC */
 25#include <asm-generic/mm_hooks.h>
 26
 27#ifdef CONFIG_MIPS_PGD_C0_CONTEXT
 28
 29#define TLBMISS_HANDLER_SETUP_PGD(pgd)				\
 30	tlbmiss_handler_setup_pgd((unsigned long)(pgd))
 31
 32extern void tlbmiss_handler_setup_pgd(unsigned long pgd);
 33
 34#define TLBMISS_HANDLER_SETUP()						\
 35	do {								\
 36		TLBMISS_HANDLER_SETUP_PGD(swapper_pg_dir);		\
 37		write_c0_xcontext((unsigned long) smp_processor_id() << 51); \
 38	} while (0)
 39
 40
 41static inline unsigned long get_current_pgd(void)
 42{
 43	return PHYS_TO_XKSEG_CACHED((read_c0_context() >> 11) & ~0xfffUL);
 44}
 45
 46#else /* CONFIG_MIPS_PGD_C0_CONTEXT: using  pgd_current*/
 47
 48/*
 49 * For the fast tlb miss handlers, we keep a per cpu array of pointers
 50 * to the current pgd for each processor. Also, the proc. id is stuffed
 51 * into the context register.
 52 */
 53extern unsigned long pgd_current[];
 54
 55#define TLBMISS_HANDLER_SETUP_PGD(pgd) \
 56	pgd_current[smp_processor_id()] = (unsigned long)(pgd)
 57
 58#ifdef CONFIG_32BIT
 59#define TLBMISS_HANDLER_SETUP()						\
 60	write_c0_context((unsigned long) smp_processor_id() << 25);	\
 61	back_to_back_c0_hazard();					\
 62	TLBMISS_HANDLER_SETUP_PGD(swapper_pg_dir)
 63#endif
 64#ifdef CONFIG_64BIT
 65#define TLBMISS_HANDLER_SETUP()						\
 66	write_c0_context((unsigned long) smp_processor_id() << 26);	\
 67	back_to_back_c0_hazard();					\
 68	TLBMISS_HANDLER_SETUP_PGD(swapper_pg_dir)
 69#endif
 70#endif /* CONFIG_MIPS_PGD_C0_CONTEXT*/
 71#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
 72
 73#define ASID_INC	0x40
 74#define ASID_MASK	0xfc0
 75
 76#elif defined(CONFIG_CPU_R8000)
 77
 78#define ASID_INC	0x10
 79#define ASID_MASK	0xff0
 80
 81#elif defined(CONFIG_CPU_RM9000)
 82
 83#define ASID_INC	0x1
 84#define ASID_MASK	0xfff
 85
 86/* SMTC/34K debug hack - but maybe we'll keep it */
 87#elif defined(CONFIG_MIPS_MT_SMTC)
 88
 89#define ASID_INC	0x1
 90extern unsigned long smtc_asid_mask;
 91#define ASID_MASK	(smtc_asid_mask)
 92#define	HW_ASID_MASK	0xff
 93/* End SMTC/34K debug hack */
 94#else /* FIXME: not correct for R6000 */
 95
 96#define ASID_INC	0x1
 97#define ASID_MASK	0xff
 98
 99#endif
100
101#define cpu_context(cpu, mm)	((mm)->context.asid[cpu])
102#define cpu_asid(cpu, mm)	(cpu_context((cpu), (mm)) & ASID_MASK)
103#define asid_cache(cpu)		(cpu_data[cpu].asid_cache)
104
105static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
106{
107}
108
109/*
110 *  All unused by hardware upper bits will be considered
111 *  as a software asid extension.
112 */
113#define ASID_VERSION_MASK  ((unsigned long)~(ASID_MASK|(ASID_MASK-1)))
114#define ASID_FIRST_VERSION ((unsigned long)(~ASID_VERSION_MASK) + 1)
115
116#ifndef CONFIG_MIPS_MT_SMTC
117/* Normal, classic MIPS get_new_mmu_context */
118static inline void
119get_new_mmu_context(struct mm_struct *mm, unsigned long cpu)
120{
121	unsigned long asid = asid_cache(cpu);
122
123	if (! ((asid += ASID_INC) & ASID_MASK) ) {
124		if (cpu_has_vtag_icache)
125			flush_icache_all();
126		local_flush_tlb_all();	/* start new asid cycle */
127		if (!asid)		/* fix version if needed */
128			asid = ASID_FIRST_VERSION;
129	}
130	cpu_context(cpu, mm) = asid_cache(cpu) = asid;
131}
132
133#else /* CONFIG_MIPS_MT_SMTC */
134
135#define get_new_mmu_context(mm, cpu) smtc_get_new_mmu_context((mm), (cpu))
136
137#endif /* CONFIG_MIPS_MT_SMTC */
138
139/*
140 * Initialize the context related info for a new mm_struct
141 * instance.
142 */
143static inline int
144init_new_context(struct task_struct *tsk, struct mm_struct *mm)
145{
146	int i;
147
148	for_each_online_cpu(i)
149		cpu_context(i, mm) = 0;
150
151	return 0;
152}
153
154static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
155                             struct task_struct *tsk)
156{
157	unsigned int cpu = smp_processor_id();
158	unsigned long flags;
159#ifdef CONFIG_MIPS_MT_SMTC
160	unsigned long oldasid;
161	unsigned long mtflags;
162	int mytlb = (smtc_status & SMTC_TLB_SHARED) ? 0 : cpu_data[cpu].vpe_id;
163	local_irq_save(flags);
164	mtflags = dvpe();
165#else /* Not SMTC */
166	local_irq_save(flags);
167#endif /* CONFIG_MIPS_MT_SMTC */
168
169	/* Check if our ASID is of an older version and thus invalid */
170	if ((cpu_context(cpu, next) ^ asid_cache(cpu)) & ASID_VERSION_MASK)
171		get_new_mmu_context(next, cpu);
172#ifdef CONFIG_MIPS_MT_SMTC
173	/*
174	 * If the EntryHi ASID being replaced happens to be
175	 * the value flagged at ASID recycling time as having
176	 * an extended life, clear the bit showing it being
177	 * in use by this "CPU", and if that's the last bit,
178	 * free up the ASID value for use and flush any old
179	 * instances of it from the TLB.
180	 */
181	oldasid = (read_c0_entryhi() & ASID_MASK);
182	if(smtc_live_asid[mytlb][oldasid]) {
183		smtc_live_asid[mytlb][oldasid] &= ~(0x1 << cpu);
184		if(smtc_live_asid[mytlb][oldasid] == 0)
185			smtc_flush_tlb_asid(oldasid);
186	}
187	/*
188	 * Tread softly on EntryHi, and so long as we support
189	 * having ASID_MASK smaller than the hardware maximum,
190	 * make sure no "soft" bits become "hard"...
191	 */
192	write_c0_entryhi((read_c0_entryhi() & ~HW_ASID_MASK) |
193			 cpu_asid(cpu, next));
194	ehb(); /* Make sure it propagates to TCStatus */
195	evpe(mtflags);
196#else
197	write_c0_entryhi(cpu_asid(cpu, next));
198#endif /* CONFIG_MIPS_MT_SMTC */
199	TLBMISS_HANDLER_SETUP_PGD(next->pgd);
200
201	/*
202	 * Mark current->active_mm as not "active" anymore.
203	 * We don't want to mislead possible IPI tlb flush routines.
204	 */
205	cpumask_clear_cpu(cpu, mm_cpumask(prev));
206	cpumask_set_cpu(cpu, mm_cpumask(next));
207
208	local_irq_restore(flags);
209}
210
211/*
212 * Destroy context related info for an mm_struct that is about
213 * to be put to rest.
214 */
215static inline void destroy_context(struct mm_struct *mm)
216{
217}
218
219#define deactivate_mm(tsk, mm)	do { } while (0)
220
221/*
222 * After we have set current->mm to a new value, this activates
223 * the context for the new mm so we see the new mappings.
224 */
225static inline void
226activate_mm(struct mm_struct *prev, struct mm_struct *next)
227{
228	unsigned long flags;
229	unsigned int cpu = smp_processor_id();
230
231#ifdef CONFIG_MIPS_MT_SMTC
232	unsigned long oldasid;
233	unsigned long mtflags;
234	int mytlb = (smtc_status & SMTC_TLB_SHARED) ? 0 : cpu_data[cpu].vpe_id;
235#endif /* CONFIG_MIPS_MT_SMTC */
236
237	local_irq_save(flags);
238
239	/* Unconditionally get a new ASID.  */
240	get_new_mmu_context(next, cpu);
241
242#ifdef CONFIG_MIPS_MT_SMTC
243	/* See comments for similar code above */
244	mtflags = dvpe();
245	oldasid = read_c0_entryhi() & ASID_MASK;
246	if(smtc_live_asid[mytlb][oldasid]) {
247		smtc_live_asid[mytlb][oldasid] &= ~(0x1 << cpu);
248		if(smtc_live_asid[mytlb][oldasid] == 0)
249			 smtc_flush_tlb_asid(oldasid);
250	}
251	/* See comments for similar code above */
252	write_c0_entryhi((read_c0_entryhi() & ~HW_ASID_MASK) |
253	                 cpu_asid(cpu, next));
254	ehb(); /* Make sure it propagates to TCStatus */
255	evpe(mtflags);
256#else
257	write_c0_entryhi(cpu_asid(cpu, next));
258#endif /* CONFIG_MIPS_MT_SMTC */
259	TLBMISS_HANDLER_SETUP_PGD(next->pgd);
260
261	/* mark mmu ownership change */
262	cpumask_clear_cpu(cpu, mm_cpumask(prev));
263	cpumask_set_cpu(cpu, mm_cpumask(next));
264
265	local_irq_restore(flags);
266}
267
268/*
269 * If mm is currently active_mm, we can't really drop it.  Instead,
270 * we will get a new one for it.
271 */
272static inline void
273drop_mmu_context(struct mm_struct *mm, unsigned cpu)
274{
275	unsigned long flags;
276#ifdef CONFIG_MIPS_MT_SMTC
277	unsigned long oldasid;
278	/* Can't use spinlock because called from TLB flush within DVPE */
279	unsigned int prevvpe;
280	int mytlb = (smtc_status & SMTC_TLB_SHARED) ? 0 : cpu_data[cpu].vpe_id;
281#endif /* CONFIG_MIPS_MT_SMTC */
282
283	local_irq_save(flags);
284
285	if (cpumask_test_cpu(cpu, mm_cpumask(mm)))  {
286		get_new_mmu_context(mm, cpu);
287#ifdef CONFIG_MIPS_MT_SMTC
288		/* See comments for similar code above */
289		prevvpe = dvpe();
290		oldasid = (read_c0_entryhi() & ASID_MASK);
291		if (smtc_live_asid[mytlb][oldasid]) {
292			smtc_live_asid[mytlb][oldasid] &= ~(0x1 << cpu);
293			if(smtc_live_asid[mytlb][oldasid] == 0)
294				smtc_flush_tlb_asid(oldasid);
295		}
296		/* See comments for similar code above */
297		write_c0_entryhi((read_c0_entryhi() & ~HW_ASID_MASK)
298				| cpu_asid(cpu, mm));
299		ehb(); /* Make sure it propagates to TCStatus */
300		evpe(prevvpe);
301#else /* not CONFIG_MIPS_MT_SMTC */
302		write_c0_entryhi(cpu_asid(cpu, mm));
303#endif /* CONFIG_MIPS_MT_SMTC */
304	} else {
305		/* will get a new context next time */
306#ifndef CONFIG_MIPS_MT_SMTC
307		cpu_context(cpu, mm) = 0;
308#else /* SMTC */
309		int i;
310
311		/* SMTC shares the TLB (and ASIDs) across VPEs */
312		for_each_online_cpu(i) {
313		    if((smtc_status & SMTC_TLB_SHARED)
314		    || (cpu_data[i].vpe_id == cpu_data[cpu].vpe_id))
315			cpu_context(i, mm) = 0;
316		}
317#endif /* CONFIG_MIPS_MT_SMTC */
318	}
319	local_irq_restore(flags);
320}
321
322#endif /* _ASM_MMU_CONTEXT_H */