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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/sh/mm/init.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/sh/mm/init.c')
-rw-r--r--arch/sh/mm/init.c313
1 files changed, 313 insertions, 0 deletions
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
new file mode 100644
index 000000000000..4e9c854845a4
--- /dev/null
+++ b/arch/sh/mm/init.c
@@ -0,0 +1,313 @@
+/* $Id: init.c,v 1.19 2004/02/21 04:42:16 kkojima Exp $
+ *
+ * linux/arch/sh/mm/init.c
+ *
+ * Copyright (C) 1999 Niibe Yutaka
+ * Copyright (C) 2002, 2004 Paul Mundt
+ *
+ * Based on linux/arch/i386/mm/init.c:
+ * Copyright (C) 1995 Linus Torvalds
+ */
+
+#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/smp.h>
+#include <linux/init.h>
+#include <linux/highmem.h>
+#include <linux/bootmem.h>
+#include <linux/pagemap.h>
+
+#include <asm/processor.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/mmu_context.h>
+#include <asm/io.h>
+#include <asm/tlb.h>
+#include <asm/cacheflush.h>
+#include <asm/cache.h>
+
+DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
+pgd_t swapper_pg_dir[PTRS_PER_PGD];
+
+/*
+ * Cache of MMU context last used.
+ */
+unsigned long mmu_context_cache = NO_CONTEXT;
+
+#ifdef CONFIG_MMU
+/* It'd be good if these lines were in the standard header file. */
+#define START_PFN (NODE_DATA(0)->bdata->node_boot_start >> PAGE_SHIFT)
+#define MAX_LOW_PFN (NODE_DATA(0)->bdata->node_low_pfn)
+#endif
+
+#ifdef CONFIG_DISCONTIGMEM
+pg_data_t discontig_page_data[MAX_NUMNODES];
+bootmem_data_t discontig_node_bdata[MAX_NUMNODES];
+#endif
+
+void (*copy_page)(void *from, void *to);
+void (*clear_page)(void *to);
+
+void show_mem(void)
+{
+ int i, total = 0, reserved = 0;
+ int shared = 0, cached = 0;
+
+ printk("Mem-info:\n");
+ show_free_areas();
+ printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
+ i = max_mapnr;
+ while (i-- > 0) {
+ total++;
+ if (PageReserved(mem_map+i))
+ reserved++;
+ else if (PageSwapCache(mem_map+i))
+ cached++;
+ else if (page_count(mem_map+i))
+ shared += page_count(mem_map+i) - 1;
+ }
+ printk("%d pages of RAM\n",total);
+ printk("%d reserved pages\n",reserved);
+ printk("%d pages shared\n",shared);
+ printk("%d pages swap cached\n",cached);
+}
+
+static void set_pte_phys(unsigned long addr, unsigned long phys, pgprot_t prot)
+{
+ pgd_t *pgd;
+ pmd_t *pmd;
+ pte_t *pte;
+
+ pgd = swapper_pg_dir + pgd_index(addr);
+ if (pgd_none(*pgd)) {
+ pgd_ERROR(*pgd);
+ return;
+ }
+
+ pmd = pmd_offset(pgd, addr);
+ if (pmd_none(*pmd)) {
+ pte = (pte_t *)get_zeroed_page(GFP_ATOMIC);
+ set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE | _PAGE_USER));
+ if (pte != pte_offset_kernel(pmd, 0)) {
+ pmd_ERROR(*pmd);
+ return;
+ }
+ }
+
+ pte = pte_offset_kernel(pmd, addr);
+ if (!pte_none(*pte)) {
+ pte_ERROR(*pte);
+ return;
+ }
+
+ set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, prot));
+
+ __flush_tlb_page(get_asid(), addr);
+}
+
+/*
+ * As a performance optimization, other platforms preserve the fixmap mapping
+ * across a context switch, we don't presently do this, but this could be done
+ * in a similar fashion as to the wired TLB interface that sh64 uses (by way
+ * of the memorry mapped UTLB configuration) -- this unfortunately forces us to
+ * give up a TLB entry for each mapping we want to preserve. While this may be
+ * viable for a small number of fixmaps, it's not particularly useful for
+ * everything and needs to be carefully evaluated. (ie, we may want this for
+ * the vsyscall page).
+ *
+ * XXX: Perhaps add a _PAGE_WIRED flag or something similar that we can pass
+ * in at __set_fixmap() time to determine the appropriate behavior to follow.
+ *
+ * -- PFM.
+ */
+void __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
+{
+ unsigned long address = __fix_to_virt(idx);
+
+ if (idx >= __end_of_fixed_addresses) {
+ BUG();
+ return;
+ }
+
+ set_pte_phys(address, phys, prot);
+}
+
+/* References to section boundaries */
+
+extern char _text, _etext, _edata, __bss_start, _end;
+extern char __init_begin, __init_end;
+
+/*
+ * paging_init() sets up the page tables
+ *
+ * This routines also unmaps the page at virtual kernel address 0, so
+ * that we can trap those pesky NULL-reference errors in the kernel.
+ */
+void __init paging_init(void)
+{
+ unsigned long zones_size[MAX_NR_ZONES] = { 0, };
+
+ /*
+ * Setup some defaults for the zone sizes.. these should be safe
+ * regardless of distcontiguous memory or MMU settings.
+ */
+ zones_size[ZONE_DMA] = 0 >> PAGE_SHIFT;
+ zones_size[ZONE_NORMAL] = __MEMORY_SIZE >> PAGE_SHIFT;
+#ifdef CONFIG_HIGHMEM
+ zones_size[ZONE_HIGHMEM] = 0 >> PAGE_SHIFT;
+#endif
+
+#ifdef CONFIG_MMU
+ /*
+ * If we have an MMU, and want to be using it .. we need to adjust
+ * the zone sizes accordingly, in addition to turning it on.
+ */
+ {
+ unsigned long max_dma, low, start_pfn;
+ pgd_t *pg_dir;
+ int i;
+
+ /* We don't need kernel mapping as hardware support that. */
+ pg_dir = swapper_pg_dir;
+
+ for (i = 0; i < PTRS_PER_PGD; i++)
+ pgd_val(pg_dir[i]) = 0;
+
+ /* Turn on the MMU */
+ enable_mmu();
+
+ /* Fixup the zone sizes */
+ start_pfn = START_PFN;
+ max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
+ low = MAX_LOW_PFN;
+
+ if (low < max_dma) {
+ zones_size[ZONE_DMA] = low - start_pfn;
+ zones_size[ZONE_NORMAL] = 0;
+ } else {
+ zones_size[ZONE_DMA] = max_dma - start_pfn;
+ zones_size[ZONE_NORMAL] = low - max_dma;
+ }
+ }
+
+#elif defined(CONFIG_CPU_SH3) || defined(CONFIG_CPU_SH4)
+ /*
+ * If we don't have CONFIG_MMU set and the processor in question
+ * still has an MMU, care needs to be taken to make sure it doesn't
+ * stay on.. Since the boot loader could have potentially already
+ * turned it on, and we clearly don't want it, we simply turn it off.
+ *
+ * We don't need to do anything special for the zone sizes, since the
+ * default values that were already configured up above should be
+ * satisfactory.
+ */
+ disable_mmu();
+#endif
+ NODE_DATA(0)->node_mem_map = NULL;
+ free_area_init_node(0, NODE_DATA(0), zones_size, __MEMORY_START >> PAGE_SHIFT, 0);
+
+#ifdef CONFIG_DISCONTIGMEM
+ /*
+ * And for discontig, do some more fixups on the zone sizes..
+ */
+ zones_size[ZONE_DMA] = __MEMORY_SIZE_2ND >> PAGE_SHIFT;
+ zones_size[ZONE_NORMAL] = 0;
+ free_area_init_node(1, NODE_DATA(1), zones_size, __MEMORY_START_2ND >> PAGE_SHIFT, 0);
+#endif
+}
+
+void __init mem_init(void)
+{
+ extern unsigned long empty_zero_page[1024];
+ int codesize, reservedpages, datasize, initsize;
+ int tmp;
+ extern unsigned long memory_start;
+
+#ifdef CONFIG_MMU
+ high_memory = (void *)__va(MAX_LOW_PFN * PAGE_SIZE);
+#else
+ extern unsigned long memory_end;
+
+ high_memory = (void *)(memory_end & PAGE_MASK);
+#endif
+
+ max_mapnr = num_physpages = MAP_NR(high_memory) - MAP_NR(memory_start);
+
+ /* clear the zero-page */
+ memset(empty_zero_page, 0, PAGE_SIZE);
+ __flush_wback_region(empty_zero_page, PAGE_SIZE);
+
+ /*
+ * Setup wrappers for copy/clear_page(), these will get overridden
+ * later in the boot process if a better method is available.
+ */
+ copy_page = copy_page_slow;
+ clear_page = clear_page_slow;
+
+ /* this will put all low memory onto the freelists */
+ totalram_pages += free_all_bootmem_node(NODE_DATA(0));
+#ifdef CONFIG_DISCONTIGMEM
+ totalram_pages += free_all_bootmem_node(NODE_DATA(1));
+#endif
+ reservedpages = 0;
+ for (tmp = 0; tmp < num_physpages; tmp++)
+ /*
+ * Only count reserved RAM pages
+ */
+ if (PageReserved(mem_map+tmp))
+ reservedpages++;
+
+ codesize = (unsigned long) &_etext - (unsigned long) &_text;
+ datasize = (unsigned long) &_edata - (unsigned long) &_etext;
+ initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
+
+ printk("Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init)\n",
+ (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
+ max_mapnr << (PAGE_SHIFT-10),
+ codesize >> 10,
+ reservedpages << (PAGE_SHIFT-10),
+ datasize >> 10,
+ initsize >> 10);
+
+ p3_cache_init();
+}
+
+void free_initmem(void)
+{
+ unsigned long addr;
+
+ addr = (unsigned long)(&__init_begin);
+ for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
+ ClearPageReserved(virt_to_page(addr));
+ set_page_count(virt_to_page(addr), 1);
+ free_page(addr);
+ totalram_pages++;
+ }
+ printk ("Freeing unused kernel memory: %dk freed\n", (&__init_end - &__init_begin) >> 10);
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+ unsigned long p;
+ for (p = start; p < end; p += PAGE_SIZE) {
+ ClearPageReserved(virt_to_page(p));
+ set_page_count(virt_to_page(p), 1);
+ free_page(p);
+ totalram_pages++;
+ }
+ printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
+}
+#endif
+