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authorPaul Mundt <lethal@linux-sh.org>2008-07-29 01:09:44 +0200
committerPaul Mundt <lethal@linux-sh.org>2008-07-29 01:09:44 +0200
commitf15cbe6f1a4b4d9df59142fc8e4abb973302cf44 (patch)
tree774d7b11abaaf33561ab8268bf51ddd9ceb79025 /arch/sh/include/asm/fixmap.h
parentvideo: Kill off leaked CONFIG_FB_SH7343VOU reference. (diff)
downloadlinux-f15cbe6f1a4b4d9df59142fc8e4abb973302cf44.tar.xz
linux-f15cbe6f1a4b4d9df59142fc8e4abb973302cf44.zip
sh: migrate to arch/sh/include/
This follows the sparc changes a439fe51a1f8eb087c22dd24d69cebae4a3addac. Most of the moving about was done with Sam's directions at: http://marc.info/?l=linux-sh&m=121724823706062&w=2 with subsequent hacking and fixups entirely my fault. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'arch/sh/include/asm/fixmap.h')
-rw-r--r--arch/sh/include/asm/fixmap.h117
1 files changed, 117 insertions, 0 deletions
diff --git a/arch/sh/include/asm/fixmap.h b/arch/sh/include/asm/fixmap.h
new file mode 100644
index 000000000000..721fcc4d5e98
--- /dev/null
+++ b/arch/sh/include/asm/fixmap.h
@@ -0,0 +1,117 @@
+/*
+ * fixmap.h: compile-time virtual memory allocation
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1998 Ingo Molnar
+ *
+ * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
+ */
+
+#ifndef _ASM_FIXMAP_H
+#define _ASM_FIXMAP_H
+
+#include <linux/kernel.h>
+#include <asm/page.h>
+#ifdef CONFIG_HIGHMEM
+#include <linux/threads.h>
+#include <asm/kmap_types.h>
+#endif
+
+/*
+ * Here we define all the compile-time 'special' virtual
+ * addresses. The point is to have a constant address at
+ * compile time, but to set the physical address only
+ * in the boot process. We allocate these special addresses
+ * from the end of P3 backwards.
+ * Also this lets us do fail-safe vmalloc(), we
+ * can guarantee that these special addresses and
+ * vmalloc()-ed addresses never overlap.
+ *
+ * these 'compile-time allocated' memory buffers are
+ * fixed-size 4k pages. (or larger if used with an increment
+ * highger than 1) use fixmap_set(idx,phys) to associate
+ * physical memory with fixmap indices.
+ *
+ * TLB entries of such buffers will not be flushed across
+ * task switches.
+ */
+
+/*
+ * on UP currently we will have no trace of the fixmap mechanizm,
+ * no page table allocations, etc. This might change in the
+ * future, say framebuffers for the console driver(s) could be
+ * fix-mapped?
+ */
+enum fixed_addresses {
+#define FIX_N_COLOURS 16
+ FIX_CMAP_BEGIN,
+ FIX_CMAP_END = FIX_CMAP_BEGIN + FIX_N_COLOURS,
+ FIX_UNCACHED,
+#ifdef CONFIG_HIGHMEM
+ FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
+ FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
+#endif
+ __end_of_fixed_addresses
+};
+
+extern void __set_fixmap(enum fixed_addresses idx,
+ unsigned long phys, pgprot_t flags);
+
+#define set_fixmap(idx, phys) \
+ __set_fixmap(idx, phys, PAGE_KERNEL)
+/*
+ * Some hardware wants to get fixmapped without caching.
+ */
+#define set_fixmap_nocache(idx, phys) \
+ __set_fixmap(idx, phys, PAGE_KERNEL_NOCACHE)
+/*
+ * used by vmalloc.c.
+ *
+ * Leave one empty page between vmalloc'ed areas and
+ * the start of the fixmap, and leave one page empty
+ * at the top of mem..
+ */
+#ifdef CONFIG_SUPERH32
+#define FIXADDR_TOP (P4SEG - PAGE_SIZE)
+#else
+#define FIXADDR_TOP (0xff000000 - PAGE_SIZE)
+#endif
+#define FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT)
+#define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE)
+
+#define __fix_to_virt(x) (FIXADDR_TOP - ((x) << PAGE_SHIFT))
+#define __virt_to_fix(x) ((FIXADDR_TOP - ((x)&PAGE_MASK)) >> PAGE_SHIFT)
+
+extern void __this_fixmap_does_not_exist(void);
+
+/*
+ * 'index to address' translation. If anyone tries to use the idx
+ * directly without tranlation, we catch the bug with a NULL-deference
+ * kernel oops. Illegal ranges of incoming indices are caught too.
+ */
+static inline unsigned long fix_to_virt(const unsigned int idx)
+{
+ /*
+ * this branch gets completely eliminated after inlining,
+ * except when someone tries to use fixaddr indices in an
+ * illegal way. (such as mixing up address types or using
+ * out-of-range indices).
+ *
+ * If it doesn't get removed, the linker will complain
+ * loudly with a reasonably clear error message..
+ */
+ if (idx >= __end_of_fixed_addresses)
+ __this_fixmap_does_not_exist();
+
+ return __fix_to_virt(idx);
+}
+
+static inline unsigned long virt_to_fix(const unsigned long vaddr)
+{
+ BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START);
+ return __virt_to_fix(vaddr);
+}
+#endif