diff options
Diffstat (limited to 'arch/microblaze')
| -rw-r--r-- | arch/microblaze/include/asm/fixmap.h | 101 | ||||
| -rw-r--r-- | arch/microblaze/mm/init.c | 17 | ||||
| -rw-r--r-- | arch/microblaze/mm/pgtable.c | 11 |
3 files changed, 123 insertions, 6 deletions
diff --git a/arch/microblaze/include/asm/fixmap.h b/arch/microblaze/include/asm/fixmap.h new file mode 100644 index 000000000000..dd89754f0a8d --- /dev/null +++ b/arch/microblaze/include/asm/fixmap.h @@ -0,0 +1,101 @@ +/* + * 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 diff --git a/arch/microblaze/mm/init.c b/arch/microblaze/mm/init.c index 2253e122aa85..af87fd71a83e 100644 --- a/arch/microblaze/mm/init.c +++ b/arch/microblaze/mm/init.c @@ -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(); diff --git a/arch/microblaze/mm/pgtable.c b/arch/microblaze/mm/pgtable.c index 68f5c01e4ad1..84905da83cb7 100644 --- a/arch/microblaze/mm/pgtable.c +++ b/arch/microblaze/mm/pgtable.c @@ -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)); +} |