patch-2.3.13 linux/include/asm-m68k/mmu_context.h

• Lines: 104
• Date: Mon Aug 9 12:27:31 1999
• Orig file: v2.3.12/linux/include/asm-m68k/mmu_context.h
• Orig date: Tue May 5 21:33:34 1998

diff -u --recursive --new-file v2.3.12/linux/include/asm-m68k/mmu_context.h linux/include/asm-m68k/mmu_context.h
@@ -1,13 +1,93 @@
-#ifndef __68K_MMU_CONTEXT_H
-#define __68K_MMU_CONTEXT_H
+#ifndef __M68K_MMU_CONTEXT_H
+#define __M68K_MMU_CONTEXT_H
 
-/*
- * get a new mmu context.. do we need this on the m68k?
- */
-#define get_mmu_context(x) do { } while (0)
-
-#define init_new_context(mm)	do { } while(0)
-#define destroy_context(mm)	do { } while(0)
-#define activate_context(tsk)	do { } while(0)
+#include <asm/setup.h>
+#include <asm/page.h>
+
+extern inline void
+init_new_context(struct task_struct *tsk, struct mm_struct *mm)
+{
+	mm->context = virt_to_phys(mm->pgd);
+}
+
+#define destroy_context(mm)		do { } while(0)
+
+extern inline void switch_mm_0230(struct mm_struct *mm)
+{
+	unsigned long crp[2] = {
+		0x80000000 | _PAGE_TABLE, mm->context
+	};
+	unsigned long tmp;
+
+	asm volatile (".chip 68030");
+
+	/* flush MC68030/MC68020 caches (they are virtually addressed) */
+	asm volatile (
+		"movec %%cacr,%0;"
+		"orw %1,%0; "
+		"movec %0,%%cacr"
+		: "=d" (tmp) : "di" (FLUSH_I_AND_D));
+
+	/* Switch the root pointer. For a 030-only kernel,
+	 * avoid flushing the whole ATC, we only need to
+	 * flush the user entries. The 68851 does this by
+	 * itself. Avoid a runtime check here.
+	 */
+	asm volatile (
+#ifdef CPU_M68030_ONLY
+		"pmovefd %0,%%crp; "
+		"pflush #0,#4"
+#else
+		"pmove %0,%%crp"
+#endif
+		: : "m" (crp[0]));
+
+	asm volatile (".chip 68k");
+}
+
+extern inline void switch_mm_0460(struct mm_struct *mm)
+{
+	asm volatile (".chip 68040");
+
+	/* flush address translation cache (user entries) */
+	asm volatile ("pflushan");
+
+	/* switch the root pointer */
+	asm volatile ("movec %0,%%urp" : : "r" (mm->context));
+
+	if (CPU_IS_060) {
+		unsigned long tmp;
+
+		/* clear user entries in the branch cache */
+		asm volatile (
+			"movec %%cacr,%0; "
+		        "orl %1,%0; "
+		        "movec %0,%%cacr"
+			: "=d" (tmp): "di" (0x00200000));
+	}
+
+	asm volatile (".chip 68k");
+}
+
+static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk, unsigned cpu)
+{
+	if (prev != next) {
+		if (CPU_IS_020_OR_030)
+			switch_mm_0230(next);
+		else
+			switch_mm_0460(next);
+	}
+}
+
+extern inline void activate_mm(struct mm_struct *prev_mm,
+			       struct mm_struct *next_mm)
+{
+	next_mm->context = virt_to_phys(next_mm->pgd);
+
+	if (CPU_IS_020_OR_030)
+		switch_mm_0230(next_mm);
+	else
+		switch_mm_0460(next_mm);
+}
 
 #endif