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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/powerpc/include/asm/fixmap.h
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/powerpc/include/asm/fixmap.h')
-rw-r--r--arch/powerpc/include/asm/fixmap.h79
1 files changed, 79 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/fixmap.h b/arch/powerpc/include/asm/fixmap.h
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+++ b/arch/powerpc/include/asm/fixmap.h
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+/*
+ * 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
+ *
+ * Copyright 2008 Freescale Semiconductor Inc.
+ * Port to powerpc added by Kumar Gala
+ */
+
+#ifndef _ASM_FIXMAP_H
+#define _ASM_FIXMAP_H
+
+#ifndef __ASSEMBLY__
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#ifdef CONFIG_HIGHMEM
+#include <linux/threads.h>
+#include <asm/kmap_types.h>
+#endif
+
+#define FIXADDR_TOP ((unsigned long)(-PAGE_SIZE))
+
+/*
+ * 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 virtual memory (0xfffff000) 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.
+ */
+enum fixed_addresses {
+ FIX_HOLE,
+ /* reserve the top 128K for early debugging purposes */
+ FIX_EARLY_DEBUG_TOP = FIX_HOLE,
+ FIX_EARLY_DEBUG_BASE = FIX_EARLY_DEBUG_TOP+((128*1024)/PAGE_SIZE)-1,
+#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
+#ifdef CONFIG_PPC_8xx
+ /* For IMMR we need an aligned 512K area */
+#define FIX_IMMR_SIZE (512 * 1024 / PAGE_SIZE)
+ FIX_IMMR_START,
+ FIX_IMMR_BASE = __ALIGN_MASK(FIX_IMMR_START, FIX_IMMR_SIZE - 1) - 1 +
+ FIX_IMMR_SIZE,
+#endif
+ /* FIX_PCIE_MCFG, */
+ __end_of_fixed_addresses
+};
+
+#define __FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT)
+#define FIXADDR_START (FIXADDR_TOP - __FIXADDR_SIZE)
+
+#define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_NCG
+
+#include <asm-generic/fixmap.h>
+
+static inline void __set_fixmap(enum fixed_addresses idx,
+ phys_addr_t phys, pgprot_t flags)
+{
+ map_kernel_page(fix_to_virt(idx), phys, pgprot_val(flags));
+}
+
+#endif /* !__ASSEMBLY__ */
+#endif