Initial import

1 files changed, 214 insertions, 0 deletions

diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c
new file mode 100644
index 000000000..a10be665b
--- /dev/null
+++ b/arch/powerpc/mm/init_32.c
@@ -0,0 +1,214 @@
+/*
+ *  PowerPC version
+ *    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
+ *  PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
+ *
+ *  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/module.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/stddef.h>
+#include <linux/init.h>
+#include <linux/highmem.h>
+#include <linux/initrd.h>
+#include <linux/pagemap.h>
+#include <linux/memblock.h>
+#include <linux/gfp.h>
+#include <linux/slab.h>
+#include <linux/hugetlb.h>
+
+#include <asm/pgalloc.h>
+#include <asm/prom.h>
+#include <asm/io.h>
+#include <asm/pgtable.h>
+#include <asm/mmu.h>
+#include <asm/smp.h>
+#include <asm/machdep.h>
+#include <asm/btext.h>
+#include <asm/tlb.h>
+#include <asm/sections.h>
+#include <asm/hugetlb.h>
+
+#include "mmu_decl.h"
+
+#if defined(CONFIG_KERNEL_START_BOOL) || defined(CONFIG_LOWMEM_SIZE_BOOL)
+/* The amount of lowmem must be within 0xF0000000 - KERNELBASE. */
+#if (CONFIG_LOWMEM_SIZE > (0xF0000000 - PAGE_OFFSET))
+#error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_KERNEL_START"
+#endif
+#endif
+#define MAX_LOW_MEM	CONFIG_LOWMEM_SIZE
+
+phys_addr_t total_memory;
+phys_addr_t total_lowmem;
+
+phys_addr_t memstart_addr = (phys_addr_t)~0ull;
+EXPORT_SYMBOL(memstart_addr);
+phys_addr_t kernstart_addr;
+EXPORT_SYMBOL(kernstart_addr);
+
+#ifdef CONFIG_RELOCATABLE_PPC32
+/* Used in __va()/__pa() */
+long long virt_phys_offset;
+EXPORT_SYMBOL(virt_phys_offset);
+#endif
+
+phys_addr_t lowmem_end_addr;
+
+int boot_mapsize;
+#ifdef CONFIG_PPC_PMAC
+unsigned long agp_special_page;
+EXPORT_SYMBOL(agp_special_page);
+#endif
+
+void MMU_init(void);
+
+/* XXX should be in current.h  -- paulus */
+extern struct task_struct *current_set[NR_CPUS];
+
+/*
+ * this tells the system to map all of ram with the segregs
+ * (i.e. page tables) instead of the bats.
+ * -- Cort
+ */
+int __map_without_bats;
+int __map_without_ltlbs;
+
+/*
+ * This tells the system to allow ioremapping memory marked as reserved.
+ */
+int __allow_ioremap_reserved;
+
+/* max amount of low RAM to map in */
+unsigned long __max_low_memory = MAX_LOW_MEM;
+
+/*
+ * Check for command-line options that affect what MMU_init will do.
+ */
+void __init MMU_setup(void)
+{
+	/* Check for nobats option (used in mapin_ram). */
+	if (strstr(boot_command_line, "nobats")) {
+		__map_without_bats = 1;
+	}
+
+	if (strstr(boot_command_line, "noltlbs")) {
+		__map_without_ltlbs = 1;
+	}
+#ifdef CONFIG_DEBUG_PAGEALLOC
+	__map_without_bats = 1;
+	__map_without_ltlbs = 1;
+#endif
+}
+
+/*
+ * MMU_init sets up the basic memory mappings for the kernel,
+ * including both RAM and possibly some I/O regions,
+ * and sets up the page tables and the MMU hardware ready to go.
+ */
+void __init MMU_init(void)
+{
+	if (ppc_md.progress)
+		ppc_md.progress("MMU:enter", 0x111);
+
+	/* parse args from command line */
+	MMU_setup();
+
+	/*
+	 * Reserve gigantic pages for hugetlb.  This MUST occur before
+	 * lowmem_end_addr is initialized below.
+	 */
+	reserve_hugetlb_gpages();
+
+	if (memblock.memory.cnt > 1) {
+#ifndef CONFIG_WII
+		memblock_enforce_memory_limit(memblock.memory.regions[0].size);
+		printk(KERN_WARNING "Only using first contiguous memory region");
+#else
+		wii_memory_fixups();
+#endif
+	}
+
+	total_lowmem = total_memory = memblock_end_of_DRAM() - memstart_addr;
+	lowmem_end_addr = memstart_addr + total_lowmem;
+
+#ifdef CONFIG_FSL_BOOKE
+	/* Freescale Book-E parts expect lowmem to be mapped by fixed TLB
+	 * entries, so we need to adjust lowmem to match the amount we can map
+	 * in the fixed entries */
+	adjust_total_lowmem();
+#endif /* CONFIG_FSL_BOOKE */
+
+	if (total_lowmem > __max_low_memory) {
+		total_lowmem = __max_low_memory;
+		lowmem_end_addr = memstart_addr + total_lowmem;
+#ifndef CONFIG_HIGHMEM
+		total_memory = total_lowmem;
+		memblock_enforce_memory_limit(total_lowmem);
+#endif /* CONFIG_HIGHMEM */
+	}
+
+	/* Initialize the MMU hardware */
+	if (ppc_md.progress)
+		ppc_md.progress("MMU:hw init", 0x300);
+	MMU_init_hw();
+
+	/* Map in all of RAM starting at KERNELBASE */
+	if (ppc_md.progress)
+		ppc_md.progress("MMU:mapin", 0x301);
+	mapin_ram();
+
+	/* Initialize early top-down ioremap allocator */
+	ioremap_bot = IOREMAP_TOP;
+
+	/* Map in I/O resources */
+	if (ppc_md.progress)
+		ppc_md.progress("MMU:setio", 0x302);
+
+	if (ppc_md.progress)
+		ppc_md.progress("MMU:exit", 0x211);
+
+	/* From now on, btext is no longer BAT mapped if it was at all */
+#ifdef CONFIG_BOOTX_TEXT
+	btext_unmap();
+#endif
+
+	/* Shortly after that, the entire linear mapping will be available */
+	memblock_set_current_limit(lowmem_end_addr);
+}
+
+#ifdef CONFIG_8xx /* No 8xx specific .c file to put that in ... */
+void setup_initial_memory_limit(phys_addr_t first_memblock_base,
+				phys_addr_t first_memblock_size)
+{
+	/* We don't currently support the first MEMBLOCK not mapping 0
+	 * physical on those processors
+	 */
+	BUG_ON(first_memblock_base != 0);
+
+#ifdef CONFIG_PIN_TLB
+	/* 8xx can only access 24MB at the moment */
+	memblock_set_current_limit(min_t(u64, first_memblock_size, 0x01800000));
+#else
+	/* 8xx can only access 8MB at the moment */
+	memblock_set_current_limit(min_t(u64, first_memblock_size, 0x00800000));
+#endif
+}
+#endif /* CONFIG_8xx */