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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/m68k/mm/motorola.c
downloadlinux-2.6.34-ux500-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
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/m68k/mm/motorola.c')
-rw-r--r--arch/m68k/mm/motorola.c285
1 files changed, 285 insertions, 0 deletions
diff --git a/arch/m68k/mm/motorola.c b/arch/m68k/mm/motorola.c
new file mode 100644
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+++ b/arch/m68k/mm/motorola.c
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+/*
+ * linux/arch/m68k/motorola.c
+ *
+ * Routines specific to the Motorola MMU, originally from:
+ * linux/arch/m68k/init.c
+ * which are Copyright (C) 1995 Hamish Macdonald
+ *
+ * Moved 8/20/1999 Sam Creasey
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/bootmem.h>
+
+#include <asm/setup.h>
+#include <asm/uaccess.h>
+#include <asm/page.h>
+#include <asm/pgalloc.h>
+#include <asm/system.h>
+#include <asm/machdep.h>
+#include <asm/io.h>
+#include <asm/dma.h>
+#ifdef CONFIG_ATARI
+#include <asm/atari_stram.h>
+#endif
+
+#undef DEBUG
+
+#ifndef mm_cachebits
+/*
+ * Bits to add to page descriptors for "normal" caching mode.
+ * For 68020/030 this is 0.
+ * For 68040, this is _PAGE_CACHE040 (cachable, copyback)
+ */
+unsigned long mm_cachebits;
+EXPORT_SYMBOL(mm_cachebits);
+#endif
+
+static pte_t * __init kernel_page_table(void)
+{
+ pte_t *ptablep;
+
+ ptablep = (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE);
+
+ clear_page(ptablep);
+ __flush_page_to_ram(ptablep);
+ flush_tlb_kernel_page(ptablep);
+ nocache_page(ptablep);
+
+ return ptablep;
+}
+
+static pmd_t *last_pgtable __initdata = NULL;
+pmd_t *zero_pgtable __initdata = NULL;
+
+static pmd_t * __init kernel_ptr_table(void)
+{
+ if (!last_pgtable) {
+ unsigned long pmd, last;
+ int i;
+
+ /* Find the last ptr table that was used in head.S and
+ * reuse the remaining space in that page for further
+ * ptr tables.
+ */
+ last = (unsigned long)kernel_pg_dir;
+ for (i = 0; i < PTRS_PER_PGD; i++) {
+ if (!pgd_present(kernel_pg_dir[i]))
+ continue;
+ pmd = __pgd_page(kernel_pg_dir[i]);
+ if (pmd > last)
+ last = pmd;
+ }
+
+ last_pgtable = (pmd_t *)last;
+#ifdef DEBUG
+ printk("kernel_ptr_init: %p\n", last_pgtable);
+#endif
+ }
+
+ last_pgtable += PTRS_PER_PMD;
+ if (((unsigned long)last_pgtable & ~PAGE_MASK) == 0) {
+ last_pgtable = (pmd_t *)alloc_bootmem_low_pages(PAGE_SIZE);
+
+ clear_page(last_pgtable);
+ __flush_page_to_ram(last_pgtable);
+ flush_tlb_kernel_page(last_pgtable);
+ nocache_page(last_pgtable);
+ }
+
+ return last_pgtable;
+}
+
+static unsigned long __init
+map_chunk (unsigned long addr, long size)
+{
+#define PTRTREESIZE (256*1024)
+#define ROOTTREESIZE (32*1024*1024)
+ static unsigned long virtaddr = PAGE_OFFSET;
+ unsigned long physaddr;
+ pgd_t *pgd_dir;
+ pmd_t *pmd_dir;
+ pte_t *pte_dir;
+
+ physaddr = (addr | m68k_supervisor_cachemode |
+ _PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY);
+ if (CPU_IS_040_OR_060)
+ physaddr |= _PAGE_GLOBAL040;
+
+ while (size > 0) {
+#ifdef DEBUG
+ if (!(virtaddr & (PTRTREESIZE-1)))
+ printk ("\npa=%#lx va=%#lx ", physaddr & PAGE_MASK,
+ virtaddr);
+#endif
+ pgd_dir = pgd_offset_k(virtaddr);
+ if (virtaddr && CPU_IS_020_OR_030) {
+ if (!(virtaddr & (ROOTTREESIZE-1)) &&
+ size >= ROOTTREESIZE) {
+#ifdef DEBUG
+ printk ("[very early term]");
+#endif
+ pgd_val(*pgd_dir) = physaddr;
+ size -= ROOTTREESIZE;
+ virtaddr += ROOTTREESIZE;
+ physaddr += ROOTTREESIZE;
+ continue;
+ }
+ }
+ if (!pgd_present(*pgd_dir)) {
+ pmd_dir = kernel_ptr_table();
+#ifdef DEBUG
+ printk ("[new pointer %p]", pmd_dir);
+#endif
+ pgd_set(pgd_dir, pmd_dir);
+ } else
+ pmd_dir = pmd_offset(pgd_dir, virtaddr);
+
+ if (CPU_IS_020_OR_030) {
+ if (virtaddr) {
+#ifdef DEBUG
+ printk ("[early term]");
+#endif
+ pmd_dir->pmd[(virtaddr/PTRTREESIZE) & 15] = physaddr;
+ physaddr += PTRTREESIZE;
+ } else {
+ int i;
+#ifdef DEBUG
+ printk ("[zero map]");
+#endif
+ zero_pgtable = kernel_ptr_table();
+ pte_dir = (pte_t *)zero_pgtable;
+ pmd_dir->pmd[0] = virt_to_phys(pte_dir) |
+ _PAGE_TABLE | _PAGE_ACCESSED;
+ pte_val(*pte_dir++) = 0;
+ physaddr += PAGE_SIZE;
+ for (i = 1; i < 64; physaddr += PAGE_SIZE, i++)
+ pte_val(*pte_dir++) = physaddr;
+ }
+ size -= PTRTREESIZE;
+ virtaddr += PTRTREESIZE;
+ } else {
+ if (!pmd_present(*pmd_dir)) {
+#ifdef DEBUG
+ printk ("[new table]");
+#endif
+ pte_dir = kernel_page_table();
+ pmd_set(pmd_dir, pte_dir);
+ }
+ pte_dir = pte_offset_kernel(pmd_dir, virtaddr);
+
+ if (virtaddr) {
+ if (!pte_present(*pte_dir))
+ pte_val(*pte_dir) = physaddr;
+ } else
+ pte_val(*pte_dir) = 0;
+ size -= PAGE_SIZE;
+ virtaddr += PAGE_SIZE;
+ physaddr += PAGE_SIZE;
+ }
+
+ }
+#ifdef DEBUG
+ printk("\n");
+#endif
+
+ return virtaddr;
+}
+
+/*
+ * paging_init() continues the virtual memory environment setup which
+ * was begun by the code in arch/head.S.
+ */
+void __init paging_init(void)
+{
+ int chunk;
+ unsigned long mem_avail = 0;
+ unsigned long zones_size[3] = { 0, };
+
+#ifdef DEBUG
+ {
+ extern unsigned long availmem;
+ printk ("start of paging_init (%p, %lx, %lx, %lx)\n",
+ kernel_pg_dir, availmem, start_mem, end_mem);
+ }
+#endif
+
+ /* Fix the cache mode in the page descriptors for the 680[46]0. */
+ if (CPU_IS_040_OR_060) {
+ int i;
+#ifndef mm_cachebits
+ mm_cachebits = _PAGE_CACHE040;
+#endif
+ for (i = 0; i < 16; i++)
+ pgprot_val(protection_map[i]) |= _PAGE_CACHE040;
+ }
+
+ /*
+ * Map the physical memory available into the kernel virtual
+ * address space. It may allocate some memory for page
+ * tables and thus modify availmem.
+ */
+
+ for (chunk = 0; chunk < m68k_num_memory; chunk++) {
+ mem_avail = map_chunk (m68k_memory[chunk].addr,
+ m68k_memory[chunk].size);
+
+ }
+
+ flush_tlb_all();
+#ifdef DEBUG
+ printk ("memory available is %ldKB\n", mem_avail >> 10);
+ printk ("start_mem is %#lx\nvirtual_end is %#lx\n",
+ start_mem, end_mem);
+#endif
+
+ /*
+ * initialize the bad page table and bad page to point
+ * to a couple of allocated pages
+ */
+ empty_zero_page = alloc_bootmem_pages(PAGE_SIZE);
+ memset(empty_zero_page, 0, PAGE_SIZE);
+
+ /*
+ * Set up SFC/DFC registers
+ */
+ set_fs(KERNEL_DS);
+
+#ifdef DEBUG
+ printk ("before free_area_init\n");
+#endif
+ zones_size[0] = (mach_max_dma_address < (unsigned long)high_memory ?
+ (mach_max_dma_address+1) : (unsigned long)high_memory);
+ zones_size[1] = (unsigned long)high_memory - zones_size[0];
+
+ zones_size[0] = (zones_size[0] - PAGE_OFFSET) >> PAGE_SHIFT;
+ zones_size[1] >>= PAGE_SHIFT;
+
+ free_area_init(zones_size);
+}
+
+extern char __init_begin, __init_end;
+
+void free_initmem(void)
+{
+ unsigned long addr;
+
+ addr = (unsigned long)&__init_begin;
+ for (; addr < (unsigned long)&__init_end; addr += PAGE_SIZE) {
+ virt_to_page(addr)->flags &= ~(1 << PG_reserved);
+ set_page_count(virt_to_page(addr), 1);
+ free_page(addr);
+ totalram_pages++;
+ }
+}
+
+