--- /dev/null
+/*
+ * 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
+ * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
+ * 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/config.h>
+#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/bootmem.h>
+#include <linux/highmem.h>
+#include <linux/initrd.h>
+#include <linux/pagemap.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/smp.h>
+#include <asm/machdep.h>
+#include <asm/btext.h>
+#include <asm/tlb.h>
+#include <asm/prom.h>
+#include <asm/lmb.h>
+#include <asm/sections.h>
+
+#include "mmu_decl.h"
+
+#if defined(CONFIG_KERNEL_START_BOOL) || defined(CONFIG_LOWMEM_SIZE_BOOL)
+/* The ammount of lowmem must be within 0xF0000000 - KERNELBASE. */
+#if (CONFIG_LOWMEM_SIZE > (0xF0000000 - KERNELBASE))
+#error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_START_KERNEL"
+#endif
+#endif
+#define MAX_LOW_MEM CONFIG_LOWMEM_SIZE
+
+DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
+
+unsigned long total_memory;
+unsigned long total_lowmem;
+
+unsigned long ppc_memstart;
+unsigned long ppc_memoffset = PAGE_OFFSET;
+
+int boot_mapsize;
+#ifdef CONFIG_PPC_PMAC
+unsigned long agp_special_page;
+EXPORT_SYMBOL(agp_special_page);
+#endif
+
+#ifdef CONFIG_HIGHMEM
+pte_t *kmap_pte;
+pgprot_t kmap_prot;
+
+EXPORT_SYMBOL(kmap_prot);
+EXPORT_SYMBOL(kmap_pte);
+#endif
+
+void MMU_init(void);
+
+/* XXX should be in current.h -- paulus */
+extern struct task_struct *current_set[NR_CPUS];
+
+extern int init_bootmem_done;
+
+/*
+ * 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;
+
+/* max amount of low RAM to map in */
+unsigned long __max_low_memory = MAX_LOW_MEM;
+
+/*
+ * limit of what is accessible with initial MMU setup -
+ * 256MB usually, but only 16MB on 601.
+ */
+unsigned long __initial_memory_limit = 0x10000000;
+
+/*
+ * Check for command-line options that affect what MMU_init will do.
+ */
+void MMU_setup(void)
+{
+ /* Check for nobats option (used in mapin_ram). */
+ if (strstr(cmd_line, "nobats")) {
+ __map_without_bats = 1;
+ }
+
+ if (strstr(cmd_line, "noltlbs")) {
+ __map_without_ltlbs = 1;
+ }
+}
+
+/*
+ * 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);
+
+ /* 601 can only access 16MB at the moment */
+ if (PVR_VER(mfspr(SPRN_PVR)) == 1)
+ __initial_memory_limit = 0x01000000;
+
+ /* parse args from command line */
+ MMU_setup();
+
+ if (lmb.memory.cnt > 1) {
+ lmb.memory.cnt = 1;
+ lmb_analyze();
+ printk(KERN_WARNING "Only using first contiguous memory region");
+ }
+
+ total_memory = lmb_end_of_DRAM();
+ total_lowmem = total_memory;
+
+#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;
+#ifndef CONFIG_HIGHMEM
+ total_memory = total_lowmem;
+ lmb_enforce_memory_limit(total_lowmem);
+ lmb_analyze();
+#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();
+
+#ifdef CONFIG_HIGHMEM
+ ioremap_base = PKMAP_BASE;
+#else
+ ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */
+#endif /* CONFIG_HIGHMEM */
+ ioremap_bot = ioremap_base;
+
+ /* Map in I/O resources */
+ if (ppc_md.progress)
+ ppc_md.progress("MMU:setio", 0x302);
+ if (ppc_md.setup_io_mappings)
+ ppc_md.setup_io_mappings();
+
+ /* Initialize the context management stuff */
+ mmu_context_init();
+
+ 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
+}
+
+/* This is only called until mem_init is done. */
+void __init *early_get_page(void)
+{
+ void *p;
+
+ if (init_bootmem_done) {
+ p = alloc_bootmem_pages(PAGE_SIZE);
+ } else {
+ p = __va(lmb_alloc_base(PAGE_SIZE, PAGE_SIZE,
+ __initial_memory_limit));
+ }
+ return p;
+}
+
+/* Free up now-unused memory */
+static void free_sec(unsigned long start, unsigned long end, const char *name)
+{
+ unsigned long cnt = 0;
+
+ while (start < end) {
+ ClearPageReserved(virt_to_page(start));
+ init_page_count(virt_to_page(start));
+ free_page(start);
+ cnt++;
+ start += PAGE_SIZE;
+ }
+ if (cnt) {
+ printk(" %ldk %s", cnt << (PAGE_SHIFT - 10), name);
+ totalram_pages += cnt;
+ }
+}
+
+void free_initmem(void)
+{
+#define FREESEC(TYPE) \
+ free_sec((unsigned long)(&__ ## TYPE ## _begin), \
+ (unsigned long)(&__ ## TYPE ## _end), \
+ #TYPE);
+
+ printk ("Freeing unused kernel memory:");
+ FREESEC(init);
+ printk("\n");
+ ppc_md.progress = NULL;
+#undef FREESEC
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+ if (start < end)
+ printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
+ for (; start < end; start += PAGE_SIZE) {
+ ClearPageReserved(virt_to_page(start));
+ init_page_count(virt_to_page(start));
+ free_page(start);
+ totalram_pages++;
+ }
+}
+#endif
git://git.onelab.eu / linux-2.6.git / blobdiff