1#ifndef _PARISC_TLBFLUSH_H
2#define _PARISC_TLBFLUSH_H
3
4/* TLB flushing routines.... */
5
6#include <linux/mm.h>
7#include <linux/sched.h>
8#include <asm/mmu_context.h>
9
10
11/* This is for the serialisation of PxTLB broadcasts.  At least on the
12 * N class systems, only one PxTLB inter processor broadcast can be
13 * active at any one time on the Merced bus.  This tlb purge
14 * synchronisation is fairly lightweight and harmless so we activate
15 * it on all systems not just the N class.
16
17 * It is also used to ensure PTE updates are atomic and consistent
18 * with the TLB.
19 */
20extern spinlock_t pa_tlb_lock;
21
22#define purge_tlb_start(flags)	spin_lock_irqsave(&pa_tlb_lock, flags)
23#define purge_tlb_end(flags)	spin_unlock_irqrestore(&pa_tlb_lock, flags)
24
25extern void flush_tlb_all(void);
26extern void flush_tlb_all_local(void *);
27
28#define smp_flush_tlb_all()	flush_tlb_all()
29
30int __flush_tlb_range(unsigned long sid,
31	unsigned long start, unsigned long end);
32
33#define flush_tlb_range(vma, start, end) \
34	__flush_tlb_range((vma)->vm_mm->context, start, end)
35
36#define flush_tlb_kernel_range(start, end) \
37	__flush_tlb_range(0, start, end)
38
39/*
40 * flush_tlb_mm()
41 *
42 * The code to switch to a new context is NOT valid for processes
43 * which play with the space id's.  Thus, we have to preserve the
44 * space and just flush the entire tlb.  However, the compilers,
45 * dynamic linker, etc, do not manipulate space id's, so there
46 * could be a significant performance benefit in switching contexts
47 * and not flushing the whole tlb.
48 */
49
50static inline void flush_tlb_mm(struct mm_struct *mm)
51{
52	BUG_ON(mm == &init_mm); /* Should never happen */
53
54#if 1 || defined(CONFIG_SMP)
55	/* Except for very small threads, flushing the whole TLB is
56	 * faster than using __flush_tlb_range.  The pdtlb and pitlb
57	 * instructions are very slow because of the TLB broadcast.
58	 * It might be faster to do local range flushes on all CPUs
59	 * on PA 2.0 systems.
60	 */
61	flush_tlb_all();
62#else
63	/* FIXME: currently broken, causing space id and protection ids
64	 * to go out of sync, resulting in faults on userspace accesses.
65	 * This approach needs further investigation since running many
66	 * small applications (e.g., GCC testsuite) is faster on HP-UX.
67	 */
68	if (mm) {
69		if (mm->context != 0)
70			free_sid(mm->context);
71		mm->context = alloc_sid();
72		if (mm == current->active_mm)
73			load_context(mm->context);
74	}
75#endif
76}
77
78static inline void flush_tlb_page(struct vm_area_struct *vma,
79	unsigned long addr)
80{
81	unsigned long flags, sid;
82
83	sid = vma->vm_mm->context;
84	purge_tlb_start(flags);
85	mtsp(sid, 1);
86	pdtlb(addr);
87	if (unlikely(split_tlb))
88		pitlb(addr);
89	purge_tlb_end(flags);
90}
91#endif
92