microblaze: Introduce fixmap (41938761) · Commits · EulixOS / Software / Kernel

arch/microblaze/include/asm/fixmap.h

0 → 100644

+101 −0

Original line number	Diff line number	Diff line
		/*
		* 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
		*
		* Copyright 2011 Michal Simek <monstr@monstr.eu>
		* Copyright 2011 PetaLogix Qld Pty Ltd
		* Port to Microblaze
		*/

		#ifndef _ASM_FIXMAP_H
		#define _ASM_FIXMAP_H

		#ifndef __ASSEMBLY__
		#include <linux/kernel.h>
		#include <asm/page.h>

		#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,
		__end_of_fixed_addresses
		};

		extern void __set_fixmap(enum fixed_addresses idx,
		phys_addr_t 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_CI)

		#define clear_fixmap(idx) \
		__set_fixmap(idx, 0, __pgprot(0))

		#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 __always_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 /* !__ASSEMBLY__ */
		#endif

arch/microblaze/mm/init.c

+11 −6

Original line number	Diff line number	Diff line
		@@ -24,6 +24,7 @@
		#include <asm/pgalloc.h>
		#include <asm/sections.h>
		#include <asm/tlb.h>
		#include <asm/fixmap.h>

		/* Use for MMU and noMMU because of PCI generic code */
		int mem_init_done;
		@@ -54,6 +55,13 @@ unsigned long lowmem_size;
		static void __init paging_init(void)
		{
		unsigned long zones_size[MAX_NR_ZONES];
		#ifdef CONFIG_MMU
		int idx;

		/* Setup fixmaps */
		for (idx = 0; idx < __end_of_fixed_addresses; idx++)
		clear_fixmap(idx);
		#endif

		/* Clean every zones */
		memset(zones_size, 0, sizeof(zones_size));
		@@ -316,12 +324,9 @@ asmlinkage void __init mmu_init(void)
		/* Map in all of RAM starting at CONFIG_KERNEL_START */
		mapin_ram();

		#ifdef CONFIG_HIGHMEM_START_BOOL
		ioremap_base = CONFIG_HIGHMEM_START;
		#else
		ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */
		#endif /* CONFIG_HIGHMEM_START_BOOL */
		ioremap_bot = ioremap_base;
		/* Extend vmalloc and ioremap area as big as possible */
		ioremap_base = ioremap_bot = FIXADDR_START;

		/* Initialize the context management stuff */
		mmu_context_init();

arch/microblaze/mm/pgtable.c

+11 −0

Original line number	Diff line number	Diff line
		@@ -37,6 +37,7 @@
		#include <linux/io.h>
		#include <asm/mmu.h>
		#include <asm/sections.h>
		#include <asm/fixmap.h>

		#define flush_HPTE(X, va, pg) _tlbie(va)

		@@ -249,3 +250,13 @@ __init_refok pte_t pte_alloc_one_kernel(struct mm_struct mm,
		}
		return pte;
		}

		void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags)
		{
		unsigned long address = __fix_to_virt(idx);

		if (idx >= __end_of_fixed_addresses)
		BUG();

		map_page(address, phys, pgprot_val(flags));
		}