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-rw-r--r--arch/alpha/include/asm/mmu_context.h259
1 files changed, 0 insertions, 259 deletions
diff --git a/arch/alpha/include/asm/mmu_context.h b/arch/alpha/include/asm/mmu_context.h
deleted file mode 100644
index 4c51c05..0000000
--- a/arch/alpha/include/asm/mmu_context.h
+++ /dev/null
@@ -1,259 +0,0 @@
-#ifndef __ALPHA_MMU_CONTEXT_H
-#define __ALPHA_MMU_CONTEXT_H
-
-/*
- * get a new mmu context..
- *
- * Copyright (C) 1996, Linus Torvalds
- */
-
-#include <asm/machvec.h>
-#include <asm/compiler.h>
-#include <asm-generic/mm_hooks.h>
-
-/*
- * Force a context reload. This is needed when we change the page
- * table pointer or when we update the ASN of the current process.
- */
-
-/* Don't get into trouble with dueling __EXTERN_INLINEs. */
-#ifndef __EXTERN_INLINE
-#include <asm/io.h>
-#endif
-
-
-static inline unsigned long
-__reload_thread(struct pcb_struct *pcb)
-{
- register unsigned long a0 __asm__("$16");
- register unsigned long v0 __asm__("$0");
-
- a0 = virt_to_phys(pcb);
- __asm__ __volatile__(
- "call_pal %2 #__reload_thread"
- : "=r"(v0), "=r"(a0)
- : "i"(PAL_swpctx), "r"(a0)
- : "$1", "$22", "$23", "$24", "$25");
-
- return v0;
-}
-
-
-/*
- * The maximum ASN's the processor supports. On the EV4 this is 63
- * but the PAL-code doesn't actually use this information. On the
- * EV5 this is 127, and EV6 has 255.
- *
- * On the EV4, the ASNs are more-or-less useless anyway, as they are
- * only used as an icache tag, not for TB entries. On the EV5 and EV6,
- * ASN's also validate the TB entries, and thus make a lot more sense.
- *
- * The EV4 ASN's don't even match the architecture manual, ugh. And
- * I quote: "If a processor implements address space numbers (ASNs),
- * and the old PTE has the Address Space Match (ASM) bit clear (ASNs
- * in use) and the Valid bit set, then entries can also effectively be
- * made coherent by assigning a new, unused ASN to the currently
- * running process and not reusing the previous ASN before calling the
- * appropriate PALcode routine to invalidate the translation buffer (TB)".
- *
- * In short, the EV4 has a "kind of" ASN capability, but it doesn't actually
- * work correctly and can thus not be used (explaining the lack of PAL-code
- * support).
- */
-#define EV4_MAX_ASN 63
-#define EV5_MAX_ASN 127
-#define EV6_MAX_ASN 255
-
-#ifdef CONFIG_ALPHA_GENERIC
-# define MAX_ASN (alpha_mv.max_asn)
-#else
-# ifdef CONFIG_ALPHA_EV4
-# define MAX_ASN EV4_MAX_ASN
-# elif defined(CONFIG_ALPHA_EV5)
-# define MAX_ASN EV5_MAX_ASN
-# else
-# define MAX_ASN EV6_MAX_ASN
-# endif
-#endif
-
-/*
- * cpu_last_asn(processor):
- * 63 0
- * +-------------+----------------+--------------+
- * | asn version | this processor | hardware asn |
- * +-------------+----------------+--------------+
- */
-
-#include <asm/smp.h>
-#ifdef CONFIG_SMP
-#define cpu_last_asn(cpuid) (cpu_data[cpuid].last_asn)
-#else
-extern unsigned long last_asn;
-#define cpu_last_asn(cpuid) last_asn
-#endif /* CONFIG_SMP */
-
-#define WIDTH_HARDWARE_ASN 8
-#define ASN_FIRST_VERSION (1UL << WIDTH_HARDWARE_ASN)
-#define HARDWARE_ASN_MASK ((1UL << WIDTH_HARDWARE_ASN) - 1)
-
-/*
- * NOTE! The way this is set up, the high bits of the "asn_cache" (and
- * the "mm->context") are the ASN _version_ code. A version of 0 is
- * always considered invalid, so to invalidate another process you only
- * need to do "p->mm->context = 0".
- *
- * If we need more ASN's than the processor has, we invalidate the old
- * user TLB's (tbiap()) and start a new ASN version. That will automatically
- * force a new asn for any other processes the next time they want to
- * run.
- */
-
-#ifndef __EXTERN_INLINE
-#define __EXTERN_INLINE extern inline
-#define __MMU_EXTERN_INLINE
-#endif
-
-extern inline unsigned long
-__get_new_mm_context(struct mm_struct *mm, long cpu)
-{
- unsigned long asn = cpu_last_asn(cpu);
- unsigned long next = asn + 1;
-
- if ((asn & HARDWARE_ASN_MASK) >= MAX_ASN) {
- tbiap();
- imb();
- next = (asn & ~HARDWARE_ASN_MASK) + ASN_FIRST_VERSION;
- }
- cpu_last_asn(cpu) = next;
- return next;
-}
-
-__EXTERN_INLINE void
-ev5_switch_mm(struct mm_struct *prev_mm, struct mm_struct *next_mm,
- struct task_struct *next)
-{
- /* Check if our ASN is of an older version, and thus invalid. */
- unsigned long asn;
- unsigned long mmc;
- long cpu = smp_processor_id();
-
-#ifdef CONFIG_SMP
- cpu_data[cpu].asn_lock = 1;
- barrier();
-#endif
- asn = cpu_last_asn(cpu);
- mmc = next_mm->context[cpu];
- if ((mmc ^ asn) & ~HARDWARE_ASN_MASK) {
- mmc = __get_new_mm_context(next_mm, cpu);
- next_mm->context[cpu] = mmc;
- }
-#ifdef CONFIG_SMP
- else
- cpu_data[cpu].need_new_asn = 1;
-#endif
-
- /* Always update the PCB ASN. Another thread may have allocated
- a new mm->context (via flush_tlb_mm) without the ASN serial
- number wrapping. We have no way to detect when this is needed. */
- task_thread_info(next)->pcb.asn = mmc & HARDWARE_ASN_MASK;
-}
-
-__EXTERN_INLINE void
-ev4_switch_mm(struct mm_struct *prev_mm, struct mm_struct *next_mm,
- struct task_struct *next)
-{
- /* As described, ASN's are broken for TLB usage. But we can
- optimize for switching between threads -- if the mm is
- unchanged from current we needn't flush. */
- /* ??? May not be needed because EV4 PALcode recognizes that
- ASN's are broken and does a tbiap itself on swpctx, under
- the "Must set ASN or flush" rule. At least this is true
- for a 1992 SRM, reports Joseph Martin (jmartin@hlo.dec.com).
- I'm going to leave this here anyway, just to Be Sure. -- r~ */
- if (prev_mm != next_mm)
- tbiap();
-
- /* Do continue to allocate ASNs, because we can still use them
- to avoid flushing the icache. */
- ev5_switch_mm(prev_mm, next_mm, next);
-}
-
-extern void __load_new_mm_context(struct mm_struct *);
-
-#ifdef CONFIG_SMP
-#define check_mmu_context() \
-do { \
- int cpu = smp_processor_id(); \
- cpu_data[cpu].asn_lock = 0; \
- barrier(); \
- if (cpu_data[cpu].need_new_asn) { \
- struct mm_struct * mm = current->active_mm; \
- cpu_data[cpu].need_new_asn = 0; \
- if (!mm->context[cpu]) \
- __load_new_mm_context(mm); \
- } \
-} while(0)
-#else
-#define check_mmu_context() do { } while(0)
-#endif
-
-__EXTERN_INLINE void
-ev5_activate_mm(struct mm_struct *prev_mm, struct mm_struct *next_mm)
-{
- __load_new_mm_context(next_mm);
-}
-
-__EXTERN_INLINE void
-ev4_activate_mm(struct mm_struct *prev_mm, struct mm_struct *next_mm)
-{
- __load_new_mm_context(next_mm);
- tbiap();
-}
-
-#define deactivate_mm(tsk,mm) do { } while (0)
-
-#ifdef CONFIG_ALPHA_GENERIC
-# define switch_mm(a,b,c) alpha_mv.mv_switch_mm((a),(b),(c))
-# define activate_mm(x,y) alpha_mv.mv_activate_mm((x),(y))
-#else
-# ifdef CONFIG_ALPHA_EV4
-# define switch_mm(a,b,c) ev4_switch_mm((a),(b),(c))
-# define activate_mm(x,y) ev4_activate_mm((x),(y))
-# else
-# define switch_mm(a,b,c) ev5_switch_mm((a),(b),(c))
-# define activate_mm(x,y) ev5_activate_mm((x),(y))
-# endif
-#endif
-
-static inline int
-init_new_context(struct task_struct *tsk, struct mm_struct *mm)
-{
- int i;
-
- for_each_online_cpu(i)
- mm->context[i] = 0;
- if (tsk != current)
- task_thread_info(tsk)->pcb.ptbr
- = ((unsigned long)mm->pgd - IDENT_ADDR) >> PAGE_SHIFT;
- return 0;
-}
-
-extern inline void
-destroy_context(struct mm_struct *mm)
-{
- /* Nothing to do. */
-}
-
-static inline void
-enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
-{
- task_thread_info(tsk)->pcb.ptbr
- = ((unsigned long)mm->pgd - IDENT_ADDR) >> PAGE_SHIFT;
-}
-
-#ifdef __MMU_EXTERN_INLINE
-#undef __EXTERN_INLINE
-#undef __MMU_EXTERN_INLINE
-#endif
-
-#endif /* __ALPHA_MMU_CONTEXT_H */