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-rw-r--r--arch/m68k/mm/kmap.c361
1 files changed, 361 insertions, 0 deletions
diff --git a/arch/m68k/mm/kmap.c b/arch/m68k/mm/kmap.c
new file mode 100644
index 00000000000..5dcb3fa35ea
--- /dev/null
+++ b/arch/m68k/mm/kmap.c
@@ -0,0 +1,361 @@
+/*
+ * linux/arch/m68k/mm/kmap.c
+ *
+ * Copyright (C) 1997 Roman Hodek
+ *
+ * 10/01/99 cleaned up the code and changing to the same interface
+ * used by other architectures /Roman Zippel
+ */
+
+#include <linux/config.h>
+#include <linux/mm.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+
+#include <asm/setup.h>
+#include <asm/segment.h>
+#include <asm/page.h>
+#include <asm/pgalloc.h>
+#include <asm/io.h>
+#include <asm/system.h>
+
+#undef DEBUG
+
+#define PTRTREESIZE (256*1024)
+
+/*
+ * For 040/060 we can use the virtual memory area like other architectures,
+ * but for 020/030 we want to use early termination page descriptor and we
+ * can't mix this with normal page descriptors, so we have to copy that code
+ * (mm/vmalloc.c) and return appriorate aligned addresses.
+ */
+
+#ifdef CPU_M68040_OR_M68060_ONLY
+
+#define IO_SIZE PAGE_SIZE
+
+static inline struct vm_struct *get_io_area(unsigned long size)
+{
+ return get_vm_area(size, VM_IOREMAP);
+}
+
+
+static inline void free_io_area(void *addr)
+{
+ vfree((void *)(PAGE_MASK & (unsigned long)addr));
+}
+
+#else
+
+#define IO_SIZE (256*1024)
+
+static struct vm_struct *iolist;
+
+static struct vm_struct *get_io_area(unsigned long size)
+{
+ unsigned long addr;
+ struct vm_struct **p, *tmp, *area;
+
+ area = (struct vm_struct *)kmalloc(sizeof(*area), GFP_KERNEL);
+ if (!area)
+ return NULL;
+ addr = KMAP_START;
+ for (p = &iolist; (tmp = *p) ; p = &tmp->next) {
+ if (size + addr < (unsigned long)tmp->addr)
+ break;
+ if (addr > KMAP_END-size)
+ return NULL;
+ addr = tmp->size + (unsigned long)tmp->addr;
+ }
+ area->addr = (void *)addr;
+ area->size = size + IO_SIZE;
+ area->next = *p;
+ *p = area;
+ return area;
+}
+
+static inline void free_io_area(void *addr)
+{
+ struct vm_struct **p, *tmp;
+
+ if (!addr)
+ return;
+ addr = (void *)((unsigned long)addr & -IO_SIZE);
+ for (p = &iolist ; (tmp = *p) ; p = &tmp->next) {
+ if (tmp->addr == addr) {
+ *p = tmp->next;
+ __iounmap(tmp->addr, tmp->size);
+ kfree(tmp);
+ return;
+ }
+ }
+}
+
+#endif
+
+/*
+ * Map some physical address range into the kernel address space. The
+ * code is copied and adapted from map_chunk().
+ */
+/* Rewritten by Andreas Schwab to remove all races. */
+
+void *__ioremap(unsigned long physaddr, unsigned long size, int cacheflag)
+{
+ struct vm_struct *area;
+ unsigned long virtaddr, retaddr;
+ long offset;
+ pgd_t *pgd_dir;
+ pmd_t *pmd_dir;
+ pte_t *pte_dir;
+
+ /*
+ * Don't allow mappings that wrap..
+ */
+ if (!size || size > physaddr + size)
+ return NULL;
+
+#ifdef CONFIG_AMIGA
+ if (MACH_IS_AMIGA) {
+ if ((physaddr >= 0x40000000) && (physaddr + size < 0x60000000)
+ && (cacheflag == IOMAP_NOCACHE_SER))
+ return (void *)physaddr;
+ }
+#endif
+
+#ifdef DEBUG
+ printk("ioremap: 0x%lx,0x%lx(%d) - ", physaddr, size, cacheflag);
+#endif
+ /*
+ * Mappings have to be aligned
+ */
+ offset = physaddr & (IO_SIZE - 1);
+ physaddr &= -IO_SIZE;
+ size = (size + offset + IO_SIZE - 1) & -IO_SIZE;
+
+ /*
+ * Ok, go for it..
+ */
+ area = get_io_area(size);
+ if (!area)
+ return NULL;
+
+ virtaddr = (unsigned long)area->addr;
+ retaddr = virtaddr + offset;
+#ifdef DEBUG
+ printk("0x%lx,0x%lx,0x%lx", physaddr, virtaddr, retaddr);
+#endif
+
+ /*
+ * add cache and table flags to physical address
+ */
+ if (CPU_IS_040_OR_060) {
+ physaddr |= (_PAGE_PRESENT | _PAGE_GLOBAL040 |
+ _PAGE_ACCESSED | _PAGE_DIRTY);
+ switch (cacheflag) {
+ case IOMAP_FULL_CACHING:
+ physaddr |= _PAGE_CACHE040;
+ break;
+ case IOMAP_NOCACHE_SER:
+ default:
+ physaddr |= _PAGE_NOCACHE_S;
+ break;
+ case IOMAP_NOCACHE_NONSER:
+ physaddr |= _PAGE_NOCACHE;
+ break;
+ case IOMAP_WRITETHROUGH:
+ physaddr |= _PAGE_CACHE040W;
+ break;
+ }
+ } else {
+ physaddr |= (_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY);
+ switch (cacheflag) {
+ case IOMAP_NOCACHE_SER:
+ case IOMAP_NOCACHE_NONSER:
+ default:
+ physaddr |= _PAGE_NOCACHE030;
+ break;
+ case IOMAP_FULL_CACHING:
+ case IOMAP_WRITETHROUGH:
+ break;
+ }
+ }
+
+ while ((long)size > 0) {
+#ifdef DEBUG
+ if (!(virtaddr & (PTRTREESIZE-1)))
+ printk ("\npa=%#lx va=%#lx ", physaddr, virtaddr);
+#endif
+ pgd_dir = pgd_offset_k(virtaddr);
+ pmd_dir = pmd_alloc(&init_mm, pgd_dir, virtaddr);
+ if (!pmd_dir) {
+ printk("ioremap: no mem for pmd_dir\n");
+ return NULL;
+ }
+
+ if (CPU_IS_020_OR_030) {
+ pmd_dir->pmd[(virtaddr/PTRTREESIZE) & 15] = physaddr;
+ physaddr += PTRTREESIZE;
+ virtaddr += PTRTREESIZE;
+ size -= PTRTREESIZE;
+ } else {
+ pte_dir = pte_alloc_kernel(&init_mm, pmd_dir, virtaddr);
+ if (!pte_dir) {
+ printk("ioremap: no mem for pte_dir\n");
+ return NULL;
+ }
+
+ pte_val(*pte_dir) = physaddr;
+ virtaddr += PAGE_SIZE;
+ physaddr += PAGE_SIZE;
+ size -= PAGE_SIZE;
+ }
+ }
+#ifdef DEBUG
+ printk("\n");
+#endif
+ flush_tlb_all();
+
+ return (void *)retaddr;
+}
+
+/*
+ * Unmap a ioremap()ed region again
+ */
+void iounmap(void *addr)
+{
+#ifdef CONFIG_AMIGA
+ if ((!MACH_IS_AMIGA) ||
+ (((unsigned long)addr < 0x40000000) ||
+ ((unsigned long)addr > 0x60000000)))
+ free_io_area(addr);
+#else
+ free_io_area(addr);
+#endif
+}
+
+/*
+ * __iounmap unmaps nearly everything, so be careful
+ * it doesn't free currently pointer/page tables anymore but it
+ * wans't used anyway and might be added later.
+ */
+void __iounmap(void *addr, unsigned long size)
+{
+ unsigned long virtaddr = (unsigned long)addr;
+ pgd_t *pgd_dir;
+ pmd_t *pmd_dir;
+ pte_t *pte_dir;
+
+ while ((long)size > 0) {
+ pgd_dir = pgd_offset_k(virtaddr);
+ if (pgd_bad(*pgd_dir)) {
+ printk("iounmap: bad pgd(%08lx)\n", pgd_val(*pgd_dir));
+ pgd_clear(pgd_dir);
+ return;
+ }
+ pmd_dir = pmd_offset(pgd_dir, virtaddr);
+
+ if (CPU_IS_020_OR_030) {
+ int pmd_off = (virtaddr/PTRTREESIZE) & 15;
+
+ if ((pmd_dir->pmd[pmd_off] & _DESCTYPE_MASK) == _PAGE_PRESENT) {
+ pmd_dir->pmd[pmd_off] = 0;
+ virtaddr += PTRTREESIZE;
+ size -= PTRTREESIZE;
+ continue;
+ }
+ }
+
+ if (pmd_bad(*pmd_dir)) {
+ printk("iounmap: bad pmd (%08lx)\n", pmd_val(*pmd_dir));
+ pmd_clear(pmd_dir);
+ return;
+ }
+ pte_dir = pte_offset_kernel(pmd_dir, virtaddr);
+
+ pte_val(*pte_dir) = 0;
+ virtaddr += PAGE_SIZE;
+ size -= PAGE_SIZE;
+ }
+
+ flush_tlb_all();
+}
+
+/*
+ * Set new cache mode for some kernel address space.
+ * The caller must push data for that range itself, if such data may already
+ * be in the cache.
+ */
+void kernel_set_cachemode(void *addr, unsigned long size, int cmode)
+{
+ unsigned long virtaddr = (unsigned long)addr;
+ pgd_t *pgd_dir;
+ pmd_t *pmd_dir;
+ pte_t *pte_dir;
+
+ if (CPU_IS_040_OR_060) {
+ switch (cmode) {
+ case IOMAP_FULL_CACHING:
+ cmode = _PAGE_CACHE040;
+ break;
+ case IOMAP_NOCACHE_SER:
+ default:
+ cmode = _PAGE_NOCACHE_S;
+ break;
+ case IOMAP_NOCACHE_NONSER:
+ cmode = _PAGE_NOCACHE;
+ break;
+ case IOMAP_WRITETHROUGH:
+ cmode = _PAGE_CACHE040W;
+ break;
+ }
+ } else {
+ switch (cmode) {
+ case IOMAP_NOCACHE_SER:
+ case IOMAP_NOCACHE_NONSER:
+ default:
+ cmode = _PAGE_NOCACHE030;
+ break;
+ case IOMAP_FULL_CACHING:
+ case IOMAP_WRITETHROUGH:
+ cmode = 0;
+ }
+ }
+
+ while ((long)size > 0) {
+ pgd_dir = pgd_offset_k(virtaddr);
+ if (pgd_bad(*pgd_dir)) {
+ printk("iocachemode: bad pgd(%08lx)\n", pgd_val(*pgd_dir));
+ pgd_clear(pgd_dir);
+ return;
+ }
+ pmd_dir = pmd_offset(pgd_dir, virtaddr);
+
+ if (CPU_IS_020_OR_030) {
+ int pmd_off = (virtaddr/PTRTREESIZE) & 15;
+
+ if ((pmd_dir->pmd[pmd_off] & _DESCTYPE_MASK) == _PAGE_PRESENT) {
+ pmd_dir->pmd[pmd_off] = (pmd_dir->pmd[pmd_off] &
+ _CACHEMASK040) | cmode;
+ virtaddr += PTRTREESIZE;
+ size -= PTRTREESIZE;
+ continue;
+ }
+ }
+
+ if (pmd_bad(*pmd_dir)) {
+ printk("iocachemode: bad pmd (%08lx)\n", pmd_val(*pmd_dir));
+ pmd_clear(pmd_dir);
+ return;
+ }
+ pte_dir = pte_offset_kernel(pmd_dir, virtaddr);
+
+ pte_val(*pte_dir) = (pte_val(*pte_dir) & _CACHEMASK040) | cmode;
+ virtaddr += PAGE_SIZE;
+ size -= PAGE_SIZE;
+ }
+
+ flush_tlb_all();
+}