#ifndef __ASM_SH64_MMU_CONTEXT_H
#define __ASM_SH64_MMU_CONTEXT_H
/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* include/asm-sh64/mmu_context.h
*
* Copyright (C) 2000, 2001 Paolo Alberelli
* Copyright (C) 2003 Paul Mundt
*
* ASID handling idea taken from MIPS implementation.
*
*/
#ifndef __ASSEMBLY__
/*
* Cache of MMU context last used.
*
* The MMU "context" consists of two things:
* (a) TLB cache version (or cycle, top 24 bits of mmu_context_cache)
* (b) ASID (Address Space IDentifier, bottom 8 bits of mmu_context_cache)
*/
extern unsigned long mmu_context_cache;
#include <asm/page.h>
/* Current mm's pgd */
extern pgd_t *mmu_pdtp_cache;
#define SR_ASID_MASK 0xffffffffff00ffffULL
#define SR_ASID_SHIFT 16
#define MMU_CONTEXT_ASID_MASK 0x000000ff
#define MMU_CONTEXT_VERSION_MASK 0xffffff00
#define MMU_CONTEXT_FIRST_VERSION 0x00000100
#define NO_CONTEXT 0
/* ASID is 8-bit value, so it can't be 0x100 */
#define MMU_NO_ASID 0x100
/*
* Virtual Page Number mask
*/
#define MMU_VPN_MASK 0xfffff000
static inline void
get_new_mmu_context(struct mm_struct *mm)
{
extern void flush_tlb_all(void);
extern void flush_cache_all(void);
unsigned long mc = ++mmu_context_cache;
if (!(mc & MMU_CONTEXT_ASID_MASK)) {
/* We exhaust ASID of this version.
Flush all TLB and start new cycle. */
flush_tlb_all();
/* We have to flush all caches as ASIDs are
used in cache */
flush_cache_all();
/* Fix version if needed.
Note that we avoid version #0/asid #0 to distingush NO_CONTEXT. */
if (!mc)
mmu_context_cache = mc = MMU_CONTEXT_FIRST_VERSION;
}
mm->context = mc;
}
/*
* Get MMU context if needed.
*/
static __inline__ void
get_mmu_context(struct mm_struct *mm)
{
if (mm) {
unsigned long mc = mmu_context_cache;
/* Check if we have old version of context.
If it's old, we need to get new context with new version. */
if ((mm->context ^ mc) & MMU_CONTEXT_VERSION_MASK)
get_new_mmu_context(mm);
}
}
/*
* Initialize the context related info for a new mm_struct
* instance.
*/
static inline int init_new_context(struct task_struct *tsk,
struct mm_struct *mm)
{
mm->context = NO_CONTEXT;
return 0;
}
/*
* Destroy context related info for an mm_struct that is about
* to be put to rest.
*/
static inline void destroy_context(struct mm_struct *mm)
{
extern void flush_tlb_mm(struct mm_struct *mm);
/* Well, at least free TLB entries */
flush_tlb_mm(mm);
}
#endif /* __ASSEMBLY__ */
/* Common defines */
#define TLB_STEP 0x00000010
#define TLB_PTEH 0x00000000
#define TLB_PTEL 0x00000008
/* PTEH defines */
#define PTEH_ASID_SHIFT 2
#define PTEH_VALID 0x0000000000000001
#define PTEH_SHARED 0x0000000000000002
#define PTEH_MATCH_ASID 0x00000000000003ff
#ifndef __ASSEMBLY__
/* This has to be a common function because the next location to fill
* information is shared. */
extern void __do_tlb_refill(unsigned long address, unsigned long long is_text_not_data, pte_t *pte);
/* Profiling counter. */
#ifdef CONFIG_SH64_PROC_TLB
extern unsigned long long calls_to_do_fast_page_fault;
#endif
static inline unsigned long get_asid(void)
{
unsigned long long sr;
asm volatile ("getcon " __SR ", %0\n\t"
: "=r" (sr));
sr = (sr >> SR_ASID_SHIFT) & MMU_CONTEXT_ASID_MASK;
return (unsigned long) sr;
}
/* Set ASID into SR */
static inline void set_asid(unsigned long asid)
{
unsigned long long sr, pc;
asm volatile ("getcon " __SR ", %0" : "=r" (sr));
sr = (sr & SR_ASID_MASK) | (asid << SR_ASID_SHIFT);
/*
* It is possible that this function may be inlined and so to avoid
* the assembler reporting duplicate symbols we make use of the gas trick
* of generating symbols using numerics and forward reference.
*/
asm volatile ("movi 1, %1\n\t"
"shlli %1, 28, %1\n\t"
"or %0, %1, %1\n\t"
"putcon %1, " __SR "\n\t"
"putcon %0, " __SSR "\n\t"
"movi 1f, %1\n\t"
"ori %1, 1 , %1\n\t"
"putcon %1, " __SPC "\n\t"
"rte\n"
"1:\n\t"
: "=r" (sr), "=r" (pc) : "0" (sr));
}
/*
* After we have set current->mm to a new value, this activates
* the context for the new mm so we see the new mappings.
*/
static __inline__ void activate_context(struct mm_struct *mm)
{
get_mmu_context(mm);
set_asid(mm->context & MMU_CONTEXT_ASID_MASK);
}
static __inline__ void switch_mm(struct mm_struct *prev,
struct mm_struct *next,
struct task_struct *tsk)
{
if (prev != next) {
mmu_pdtp_cache = next->pgd;
activate_context(next);
}
}
#define deactivate_mm(tsk,mm) do { } while (0)
#define activate_mm(prev, next) \
switch_mm((prev),(next),NULL)
static inline void
enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
{
}
#endif /* __ASSEMBLY__ */
#endif /* __ASM_SH64_MMU_CONTEXT_H */
