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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_M32R_MMU_CONTEXT_H
#define _ASM_M32R_MMU_CONTEXT_H
#ifdef __KERNEL__
#include <asm/m32r.h>
#define MMU_CONTEXT_ASID_MASK (0x000000FF)
#define MMU_CONTEXT_VERSION_MASK (0xFFFFFF00)
#define MMU_CONTEXT_FIRST_VERSION (0x00000100)
#define NO_CONTEXT (0x00000000)
#ifndef __ASSEMBLY__
#include <linux/atomic.h>
#include <linux/mm_types.h>
#include <asm/pgalloc.h>
#include <asm/mmu.h>
#include <asm/tlbflush.h>
#include <asm-generic/mm_hooks.h>
/*
* Cache of MMU context last used.
*/
#ifndef CONFIG_SMP
extern unsigned long mmu_context_cache_dat;
#define mmu_context_cache mmu_context_cache_dat
#define mm_context(mm) mm->context
#else /* not CONFIG_SMP */
extern unsigned long mmu_context_cache_dat[];
#define mmu_context_cache mmu_context_cache_dat[smp_processor_id()]
#define mm_context(mm) mm->context[smp_processor_id()]
#endif /* not CONFIG_SMP */
#define set_tlb_tag(entry, tag) (*entry = (tag & PAGE_MASK)|get_asid())
#define set_tlb_data(entry, data) (*entry = (data | _PAGE_PRESENT))
#ifdef CONFIG_MMU
#define enter_lazy_tlb(mm, tsk) do { } while (0)
static inline void get_new_mmu_context(struct mm_struct *mm)
{
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. */
local_flush_tlb_all();
/* Fix version if needed.
Note that we avoid version #0 to distinguish NO_CONTEXT. */
if (!mc)
mmu_context_cache = mc = MMU_CONTEXT_FIRST_VERSION;
}
mm_context(mm) = 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(mm) ^ 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)
{
#ifndef CONFIG_SMP
mm->context = NO_CONTEXT;
#else /* CONFIG_SMP */
int num_cpus = num_online_cpus();
int i;
for (i = 0 ; i < num_cpus ; i++)
mm->context[i] = NO_CONTEXT;
#endif /* CONFIG_SMP */
return 0;
}
/*
* Destroy context related info for an mm_struct that is about
* to be put to rest.
*/
#define destroy_context(mm) do { } while (0)
static inline void set_asid(unsigned long asid)
{
*(volatile unsigned long *)MASID = (asid & MMU_CONTEXT_ASID_MASK);
}
static inline unsigned long get_asid(void)
{
unsigned long asid;
asid = *(volatile long *)MASID;
asid &= MMU_CONTEXT_ASID_MASK;
return asid;
}
/*
* 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(mm) & MMU_CONTEXT_ASID_MASK);
}
static inline void switch_mm(struct mm_struct *prev,
struct mm_struct *next, struct task_struct *tsk)
{
#ifdef CONFIG_SMP
int cpu = smp_processor_id();
#endif /* CONFIG_SMP */
if (prev != next) {
#ifdef CONFIG_SMP
cpumask_set_cpu(cpu, mm_cpumask(next));
#endif /* CONFIG_SMP */
/* Set MPTB = next->pgd */
*(volatile unsigned long *)MPTB = (unsigned long)next->pgd;
activate_context(next);
}
#ifdef CONFIG_SMP
else
if (!cpumask_test_and_set_cpu(cpu, mm_cpumask(next)))
activate_context(next);
#endif /* CONFIG_SMP */
}
#define deactivate_mm(tsk, mm) do { } while (0)
#define activate_mm(prev, next) \
switch_mm((prev), (next), NULL)
#else /* not CONFIG_MMU */
#define get_mmu_context(mm) do { } while (0)
#define init_new_context(tsk,mm) (0)
#define destroy_context(mm) do { } while (0)
#define set_asid(asid) do { } while (0)
#define get_asid() (0)
#define activate_context(mm) do { } while (0)
#define switch_mm(prev,next,tsk) do { } while (0)
#define deactivate_mm(mm,tsk) do { } while (0)
#define activate_mm(prev,next) do { } while (0)
#define enter_lazy_tlb(mm,tsk) do { } while (0)
#endif /* not CONFIG_MMU */
#endif /* not __ASSEMBLY__ */
#endif /* __KERNEL__ */
#endif /* _ASM_M32R_MMU_CONTEXT_H */
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