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Diffstat (limited to 'include/asm-alpha/mmu_context.h')
| -rw-r--r-- | include/asm-alpha/mmu_context.h | 260 |
1 files changed, 0 insertions, 260 deletions
diff --git a/include/asm-alpha/mmu_context.h b/include/asm-alpha/mmu_context.h deleted file mode 100644 index 86c08a02d239..000000000000 --- a/include/asm-alpha/mmu_context.h +++ /dev/null @@ -1,260 +0,0 @@ -#ifndef __ALPHA_MMU_CONTEXT_H -#define __ALPHA_MMU_CONTEXT_H - -/* - * get a new mmu context.. - * - * Copyright (C) 1996, Linus Torvalds - */ - -#include <asm/system.h> -#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 */ |
