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| author | Paul Mundt <lethal@linux-sh.org> | 2010-01-18 20:42:39 +0900 |
|---|---|---|
| committer | Paul Mundt <lethal@linux-sh.org> | 2010-01-18 20:42:39 +0900 |
| commit | 8faba6121566248330e738d25a2c43d7500fb9f0 (patch) | |
| tree | 9cb09b2ec00b504dd24e1272126a22cd365e7282 /arch/sh/mm/ioremap_fixed.c | |
| parent | 4291b730cd0f0cf98a90d946b6cabbd804397350 (diff) | |
| parent | 78bf04fc96f509474c6b443b515d6b79bb7bf584 (diff) | |
| download | talos-op-linux-8faba6121566248330e738d25a2c43d7500fb9f0.tar.gz talos-op-linux-8faba6121566248330e738d25a2c43d7500fb9f0.zip | |
Merge branch 'sh/ioremap-fixed'
Diffstat (limited to 'arch/sh/mm/ioremap_fixed.c')
| -rw-r--r-- | arch/sh/mm/ioremap_fixed.c | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/arch/sh/mm/ioremap_fixed.c b/arch/sh/mm/ioremap_fixed.c new file mode 100644 index 000000000000..3a9d3d88fe8d --- /dev/null +++ b/arch/sh/mm/ioremap_fixed.c @@ -0,0 +1,144 @@ +/* + * Re-map IO memory to kernel address space so that we can access it. + * + * These functions should only be used when it is necessary to map a + * physical address space into the kernel address space before ioremap() + * can be used, e.g. early in boot before paging_init(). + * + * Copyright (C) 2009 Matt Fleming + */ + +#include <linux/vmalloc.h> +#include <linux/ioport.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/io.h> +#include <linux/bootmem.h> +#include <linux/proc_fs.h> +#include <linux/slab.h> +#include <asm/fixmap.h> +#include <asm/page.h> +#include <asm/pgalloc.h> +#include <asm/addrspace.h> +#include <asm/cacheflush.h> +#include <asm/tlbflush.h> +#include <asm/mmu.h> +#include <asm/mmu_context.h> + +struct ioremap_map { + void __iomem *addr; + unsigned long size; + unsigned long fixmap_addr; +}; + +static struct ioremap_map ioremap_maps[FIX_N_IOREMAPS]; + +void __init ioremap_fixed_init(void) +{ + struct ioremap_map *map; + int i; + + for (i = 0; i < FIX_N_IOREMAPS; i++) { + map = &ioremap_maps[i]; + map->fixmap_addr = __fix_to_virt(FIX_IOREMAP_BEGIN + i); + } +} + +void __init __iomem * +ioremap_fixed(resource_size_t phys_addr, unsigned long size, pgprot_t prot) +{ + enum fixed_addresses idx0, idx; + resource_size_t last_addr; + struct ioremap_map *map; + unsigned long offset; + unsigned int nrpages; + int i, slot; + + slot = -1; + for (i = 0; i < FIX_N_IOREMAPS; i++) { + map = &ioremap_maps[i]; + if (!map->addr) { + map->size = size; + slot = i; + break; + } + } + + if (slot < 0) + return NULL; + + /* Don't allow wraparound or zero size */ + last_addr = phys_addr + size - 1; + if (!size || last_addr < phys_addr) + return NULL; + + /* + * Fixmap mappings have to be page-aligned + */ + offset = phys_addr & ~PAGE_MASK; + phys_addr &= PAGE_MASK; + size = PAGE_ALIGN(last_addr + 1) - phys_addr; + + /* + * Mappings have to fit in the FIX_IOREMAP area. + */ + nrpages = size >> PAGE_SHIFT; + if (nrpages > FIX_N_IOREMAPS) + return NULL; + + /* + * Ok, go for it.. + */ + idx0 = FIX_IOREMAP_BEGIN + slot; + idx = idx0; + while (nrpages > 0) { + pgprot_val(prot) |= _PAGE_WIRED; + __set_fixmap(idx, phys_addr, prot); + phys_addr += PAGE_SIZE; + idx++; + --nrpages; + } + + map->addr = (void __iomem *)(offset + map->fixmap_addr); + return map->addr; +} + +void __init iounmap_fixed(void __iomem *addr) +{ + enum fixed_addresses idx; + unsigned long virt_addr; + struct ioremap_map *map; + unsigned long offset; + unsigned int nrpages; + int i, slot; + pgprot_t prot; + + slot = -1; + for (i = 0; i < FIX_N_IOREMAPS; i++) { + map = &ioremap_maps[i]; + if (map->addr == addr) { + slot = i; + break; + } + } + + if (slot < 0) + return; + + virt_addr = (unsigned long)addr; + + offset = virt_addr & ~PAGE_MASK; + nrpages = PAGE_ALIGN(offset + map->size - 1) >> PAGE_SHIFT; + + pgprot_val(prot) = _PAGE_WIRED; + + idx = FIX_IOREMAP_BEGIN + slot + nrpages; + while (nrpages > 0) { + __clear_fixmap(idx, prot); + --idx; + --nrpages; + } + + map->size = 0; + map->addr = NULL; +} |
