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-rw-r--r--arch/m68k/mm/motorola.c321
1 files changed, 321 insertions, 0 deletions
diff --git a/arch/m68k/mm/motorola.c b/arch/m68k/mm/motorola.c
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index 00000000000..8b3db1c587f
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+++ b/arch/m68k/mm/motorola.c
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+/*
+ * linux/arch/m68k/mm/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/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 <linux/gfp.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
+#include <asm/sections.h>
+
+#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
+
+/* size of memory already mapped in head.S */
+#define INIT_MAPPED_SIZE (4UL<<20)
+
+extern unsigned long availmem;
+
+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 void __init map_node(int node)
+{
+#define PTRTREESIZE (256*1024)
+#define ROOTTREESIZE (32*1024*1024)
+ unsigned long physaddr, virtaddr, size;
+ pgd_t *pgd_dir;
+ pmd_t *pmd_dir;
+ pte_t *pte_dir;
+
+ size = m68k_memory[node].size;
+ physaddr = m68k_memory[node].addr;
+ virtaddr = (unsigned long)phys_to_virt(physaddr);
+ physaddr |= 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
+}
+
+/*
+ * paging_init() continues the virtual memory environment setup which
+ * was begun by the code in arch/head.S.
+ */
+void __init paging_init(void)
+{
+ unsigned long zones_size[MAX_NR_ZONES] = { 0, };
+ unsigned long min_addr, max_addr;
+ unsigned long addr, size, end;
+ int i;
+
+#ifdef DEBUG
+ printk ("start of paging_init (%p, %lx)\n", kernel_pg_dir, availmem);
+#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;
+ }
+
+ min_addr = m68k_memory[0].addr;
+ max_addr = min_addr + m68k_memory[0].size;
+ for (i = 1; i < m68k_num_memory;) {
+ if (m68k_memory[i].addr < min_addr) {
+ printk("Ignoring memory chunk at 0x%lx:0x%lx before the first chunk\n",
+ m68k_memory[i].addr, m68k_memory[i].size);
+ printk("Fix your bootloader or use a memfile to make use of this area!\n");
+ m68k_num_memory--;
+ memmove(m68k_memory + i, m68k_memory + i + 1,
+ (m68k_num_memory - i) * sizeof(struct mem_info));
+ continue;
+ }
+ addr = m68k_memory[i].addr + m68k_memory[i].size;
+ if (addr > max_addr)
+ max_addr = addr;
+ i++;
+ }
+ m68k_memoffset = min_addr - PAGE_OFFSET;
+ m68k_virt_to_node_shift = fls(max_addr - min_addr - 1) - 6;
+
+ module_fixup(NULL, __start_fixup, __stop_fixup);
+ flush_icache();
+
+ high_memory = phys_to_virt(max_addr);
+
+ min_low_pfn = availmem >> PAGE_SHIFT;
+ max_low_pfn = max_addr >> PAGE_SHIFT;
+
+ for (i = 0; i < m68k_num_memory; i++) {
+ addr = m68k_memory[i].addr;
+ end = addr + m68k_memory[i].size;
+ m68k_setup_node(i);
+ availmem = PAGE_ALIGN(availmem);
+ availmem += init_bootmem_node(NODE_DATA(i),
+ availmem >> PAGE_SHIFT,
+ addr >> PAGE_SHIFT,
+ end >> PAGE_SHIFT);
+ }
+
+ /*
+ * Map the physical memory available into the kernel virtual
+ * address space. First initialize the bootmem allocator with
+ * the memory we already mapped, so map_node() has something
+ * to allocate.
+ */
+ addr = m68k_memory[0].addr;
+ size = m68k_memory[0].size;
+ free_bootmem_node(NODE_DATA(0), availmem, min(INIT_MAPPED_SIZE, size) - (availmem - addr));
+ map_node(0);
+ if (size > INIT_MAPPED_SIZE)
+ free_bootmem_node(NODE_DATA(0), addr + INIT_MAPPED_SIZE, size - INIT_MAPPED_SIZE);
+
+ for (i = 1; i < m68k_num_memory; i++)
+ map_node(i);
+
+ flush_tlb_all();
+
+ /*
+ * initialize the bad page table and bad page to point
+ * to a couple of allocated pages
+ */
+ empty_zero_page = alloc_bootmem_pages(PAGE_SIZE);
+
+ /*
+ * Set up SFC/DFC registers
+ */
+ set_fs(KERNEL_DS);
+
+#ifdef DEBUG
+ printk ("before free_area_init\n");
+#endif
+ for (i = 0; i < m68k_num_memory; i++) {
+ zones_size[ZONE_DMA] = m68k_memory[i].size >> PAGE_SHIFT;
+ free_area_init_node(i, zones_size,
+ m68k_memory[i].addr >> PAGE_SHIFT, NULL);
+ if (node_present_pages(i))
+ node_set_state(i, N_NORMAL_MEMORY);
+ }
+}
+
+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);
+ init_page_count(virt_to_page(addr));
+ free_page(addr);
+ totalram_pages++;
+ }
+}
+
+