patch-2.4.10 linux/arch/ppc/mm/4xx_mmu.c

• Lines: 99
• Date: Tue Aug 28 06:58:33 2001
• Orig file: v2.4.9/linux/arch/ppc/mm/4xx_mmu.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.9/linux/arch/ppc/mm/4xx_mmu.c linux/arch/ppc/mm/4xx_mmu.c
@@ -0,0 +1,98 @@
+/*
+ * BK Id: %F% %I% %G% %U% %#%
+ */
+/*
+ * This file contains the routines for initializing the MMU
+ * on the 4xx series of chips.
+ *  -- paulus
+ * 
+ *  Derived from arch/ppc/mm/init.c:
+ *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
+ *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
+ *    Copyright (C) 1996 Paul Mackerras
+ *  Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
+ *
+ *  Derived from "arch/i386/mm/init.c"
+ *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/stddef.h>
+#include <linux/vmalloc.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/bootmem.h>
+#include <linux/highmem.h>
+
+#include <asm/pgalloc.h>
+#include <asm/prom.h>
+#include <asm/io.h>
+#include <asm/mmu_context.h>
+#include <asm/pgtable.h>
+#include <asm/mmu.h>
+#include <asm/uaccess.h>
+#include <asm/smp.h>
+#include <asm/bootx.h>
+#include <asm/machdep.h>
+#include <asm/setup.h>
+
+/* Used by the 4xx TLB replacement exception handler.
+ * Just needed it declared someplace (and initialized to zero).
+ */
+unsigned int tlb_4xx_index;
+
+/*
+ * MMU_init_hw does the chip-specific initialization of the MMU hardware.
+ */
+void __init MMU_init_hw(void)
+{
+	/*
+	 * The Zone Protection Register (ZPR) defines how protection will
+	 * be applied to every page which is a member of a given zone. At
+	 * present, we utilize only two of the 4xx's zones.
+	 * The zone index bits (of ZSEL) in the PTE are used for software
+	 * indicators, except the LSB.  For user access, zone 15 is used,
+	 * for kernel access, zone 14 is used.  We set all but zone 15
+	 * to zero, allowing only kernel access as indicated in the PTE.
+	 * For zone 15, we set a 01 binary (a value of 10 will not work)
+	 * to allow user access as indicated in the PTE.  This also allows
+	 * kernel access as indicated in the PTE.
+	 */
+
+        mtspr(SPRN_ZPR, 0x00000001);
+
+	flush_instruction_cache();
+
+	/*
+	 * Set up the real-mode cache parameters for the exception vector
+	 * handlers (which are run in real-mode).
+	 */
+
+        mtspr(SPRN_DCWR, 0x00000000);	/* All caching is write-back */
+
+        /*
+	 * Cache instruction and data space where the exception
+	 * vectors and the kernel live in real-mode.
+	 */
+
+        mtspr(SPRN_DCCR, 0x80000000);	/* 128 MB of data space at 0x0. */
+        mtspr(SPRN_ICCR, 0x80000000);	/* 128 MB of instr. space at 0x0. */
+}