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-rw-r--r--include/asm-sparc64/mmu_context.h145
1 files changed, 145 insertions, 0 deletions
diff --git a/include/asm-sparc64/mmu_context.h b/include/asm-sparc64/mmu_context.h
new file mode 100644
index 00000000000..87c43c67866
--- /dev/null
+++ b/include/asm-sparc64/mmu_context.h
@@ -0,0 +1,145 @@
+/* $Id: mmu_context.h,v 1.54 2002/02/09 19:49:31 davem Exp $ */
+#ifndef __SPARC64_MMU_CONTEXT_H
+#define __SPARC64_MMU_CONTEXT_H
+
+/* Derived heavily from Linus's Alpha/AXP ASN code... */
+
+#ifndef __ASSEMBLY__
+
+#include <linux/spinlock.h>
+#include <asm/system.h>
+#include <asm/spitfire.h>
+
+static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
+{
+}
+
+extern spinlock_t ctx_alloc_lock;
+extern unsigned long tlb_context_cache;
+extern unsigned long mmu_context_bmap[];
+
+extern void get_new_mmu_context(struct mm_struct *mm);
+
+/* Initialize a new mmu context. This is invoked when a new
+ * address space instance (unique or shared) is instantiated.
+ * This just needs to set mm->context to an invalid context.
+ */
+#define init_new_context(__tsk, __mm) \
+ (((__mm)->context.sparc64_ctx_val = 0UL), 0)
+
+/* Destroy a dead context. This occurs when mmput drops the
+ * mm_users count to zero, the mmaps have been released, and
+ * all the page tables have been flushed. Our job is to destroy
+ * any remaining processor-specific state, and in the sparc64
+ * case this just means freeing up the mmu context ID held by
+ * this task if valid.
+ */
+#define destroy_context(__mm) \
+do { spin_lock(&ctx_alloc_lock); \
+ if (CTX_VALID((__mm)->context)) { \
+ unsigned long nr = CTX_NRBITS((__mm)->context); \
+ mmu_context_bmap[nr>>6] &= ~(1UL << (nr & 63)); \
+ } \
+ spin_unlock(&ctx_alloc_lock); \
+} while(0)
+
+/* Reload the two core values used by TLB miss handler
+ * processing on sparc64. They are:
+ * 1) The physical address of mm->pgd, when full page
+ * table walks are necessary, this is where the
+ * search begins.
+ * 2) A "PGD cache". For 32-bit tasks only pgd[0] is
+ * ever used since that maps the entire low 4GB
+ * completely. To speed up TLB miss processing we
+ * make this value available to the handlers. This
+ * decreases the amount of memory traffic incurred.
+ */
+#define reload_tlbmiss_state(__tsk, __mm) \
+do { \
+ register unsigned long paddr asm("o5"); \
+ register unsigned long pgd_cache asm("o4"); \
+ paddr = __pa((__mm)->pgd); \
+ pgd_cache = 0UL; \
+ if ((__tsk)->thread_info->flags & _TIF_32BIT) \
+ pgd_cache = get_pgd_cache((__mm)->pgd); \
+ __asm__ __volatile__("wrpr %%g0, 0x494, %%pstate\n\t" \
+ "mov %3, %%g4\n\t" \
+ "mov %0, %%g7\n\t" \
+ "stxa %1, [%%g4] %2\n\t" \
+ "membar #Sync\n\t" \
+ "wrpr %%g0, 0x096, %%pstate" \
+ : /* no outputs */ \
+ : "r" (paddr), "r" (pgd_cache),\
+ "i" (ASI_DMMU), "i" (TSB_REG)); \
+} while(0)
+
+/* Set MMU context in the actual hardware. */
+#define load_secondary_context(__mm) \
+ __asm__ __volatile__("stxa %0, [%1] %2\n\t" \
+ "flush %%g6" \
+ : /* No outputs */ \
+ : "r" (CTX_HWBITS((__mm)->context)), \
+ "r" (SECONDARY_CONTEXT), "i" (ASI_DMMU))
+
+extern void __flush_tlb_mm(unsigned long, unsigned long);
+
+/* Switch the current MM context. */
+static inline void switch_mm(struct mm_struct *old_mm, struct mm_struct *mm, struct task_struct *tsk)
+{
+ unsigned long ctx_valid;
+
+ spin_lock(&mm->page_table_lock);
+ if (CTX_VALID(mm->context))
+ ctx_valid = 1;
+ else
+ ctx_valid = 0;
+
+ if (!ctx_valid || (old_mm != mm)) {
+ if (!ctx_valid)
+ get_new_mmu_context(mm);
+
+ load_secondary_context(mm);
+ reload_tlbmiss_state(tsk, mm);
+ }
+
+ {
+ int cpu = smp_processor_id();
+
+ /* Even if (mm == old_mm) we _must_ check
+ * the cpu_vm_mask. If we do not we could
+ * corrupt the TLB state because of how
+ * smp_flush_tlb_{page,range,mm} on sparc64
+ * and lazy tlb switches work. -DaveM
+ */
+ if (!ctx_valid || !cpu_isset(cpu, mm->cpu_vm_mask)) {
+ cpu_set(cpu, mm->cpu_vm_mask);
+ __flush_tlb_mm(CTX_HWBITS(mm->context),
+ SECONDARY_CONTEXT);
+ }
+ }
+ spin_unlock(&mm->page_table_lock);
+}
+
+#define deactivate_mm(tsk,mm) do { } while (0)
+
+/* Activate a new MM instance for the current task. */
+static inline void activate_mm(struct mm_struct *active_mm, struct mm_struct *mm)
+{
+ int cpu;
+
+ spin_lock(&mm->page_table_lock);
+ if (!CTX_VALID(mm->context))
+ get_new_mmu_context(mm);
+ cpu = smp_processor_id();
+ if (!cpu_isset(cpu, mm->cpu_vm_mask))
+ cpu_set(cpu, mm->cpu_vm_mask);
+ spin_unlock(&mm->page_table_lock);
+
+ load_secondary_context(mm);
+ __flush_tlb_mm(CTX_HWBITS(mm->context), SECONDARY_CONTEXT);
+ reload_tlbmiss_state(current, mm);
+}
+
+#endif /* !(__ASSEMBLY__) */
+
+#endif /* !(__SPARC64_MMU_CONTEXT_H) */