| /* |
| * Re-map IO memory to kernel address space so that we can access it. |
| * This is needed for high PCI addresses that aren't mapped in the |
| * 640k-1MB IO memory area on PC's |
| * |
| * (C) Copyright 1995 1996 Linus Torvalds |
| */ |
| |
| #include <linux/bootmem.h> |
| #include <linux/init.h> |
| #include <linux/io.h> |
| #include <linux/module.h> |
| #include <linux/slab.h> |
| #include <linux/vmalloc.h> |
| #include <linux/mmiotrace.h> |
| |
| #include <asm/cacheflush.h> |
| #include <asm/e820.h> |
| #include <asm/fixmap.h> |
| #include <asm/pgtable.h> |
| #include <asm/tlbflush.h> |
| #include <asm/pgalloc.h> |
| #include <asm/pat.h> |
| |
| #ifdef CONFIG_X86_64 |
| |
| unsigned long __phys_addr(unsigned long x) |
| { |
| if (x >= __START_KERNEL_map) |
| return x - __START_KERNEL_map + phys_base; |
| return x - PAGE_OFFSET; |
| } |
| EXPORT_SYMBOL(__phys_addr); |
| |
| static inline int phys_addr_valid(unsigned long addr) |
| { |
| return addr < (1UL << boot_cpu_data.x86_phys_bits); |
| } |
| |
| #else |
| |
| static inline int phys_addr_valid(unsigned long addr) |
| { |
| return 1; |
| } |
| |
| #endif |
| |
| int page_is_ram(unsigned long pagenr) |
| { |
| resource_size_t addr, end; |
| int i; |
| |
| /* |
| * A special case is the first 4Kb of memory; |
| * This is a BIOS owned area, not kernel ram, but generally |
| * not listed as such in the E820 table. |
| */ |
| if (pagenr == 0) |
| return 0; |
| |
| /* |
| * Second special case: Some BIOSen report the PC BIOS |
| * area (640->1Mb) as ram even though it is not. |
| */ |
| if (pagenr >= (BIOS_BEGIN >> PAGE_SHIFT) && |
| pagenr < (BIOS_END >> PAGE_SHIFT)) |
| return 0; |
| |
| for (i = 0; i < e820.nr_map; i++) { |
| /* |
| * Not usable memory: |
| */ |
| if (e820.map[i].type != E820_RAM) |
| continue; |
| addr = (e820.map[i].addr + PAGE_SIZE-1) >> PAGE_SHIFT; |
| end = (e820.map[i].addr + e820.map[i].size) >> PAGE_SHIFT; |
| |
| |
| if ((pagenr >= addr) && (pagenr < end)) |
| return 1; |
| } |
| return 0; |
| } |
| |
| int pagerange_is_ram(unsigned long start, unsigned long end) |
| { |
| int ram_page = 0, not_rampage = 0; |
| unsigned long page_nr; |
| |
| for (page_nr = (start >> PAGE_SHIFT); page_nr < (end >> PAGE_SHIFT); |
| ++page_nr) { |
| if (page_is_ram(page_nr)) |
| ram_page = 1; |
| else |
| not_rampage = 1; |
| |
| if (ram_page == not_rampage) |
| return -1; |
| } |
| |
| return ram_page; |
| } |
| |
| /* |
| * Fix up the linear direct mapping of the kernel to avoid cache attribute |
| * conflicts. |
| */ |
| int ioremap_change_attr(unsigned long vaddr, unsigned long size, |
| unsigned long prot_val) |
| { |
| unsigned long nrpages = size >> PAGE_SHIFT; |
| int err; |
| |
| switch (prot_val) { |
| case _PAGE_CACHE_UC: |
| default: |
| err = _set_memory_uc(vaddr, nrpages); |
| break; |
| case _PAGE_CACHE_WC: |
| err = _set_memory_wc(vaddr, nrpages); |
| break; |
| case _PAGE_CACHE_WB: |
| err = _set_memory_wb(vaddr, nrpages); |
| break; |
| } |
| |
| return err; |
| } |
| |
| /* |
| * Remap an arbitrary physical address space into the kernel virtual |
| * address space. Needed when the kernel wants to access high addresses |
| * directly. |
| * |
| * NOTE! We need to allow non-page-aligned mappings too: we will obviously |
| * have to convert them into an offset in a page-aligned mapping, but the |
| * caller shouldn't need to know that small detail. |
| */ |
| static void __iomem *__ioremap_caller(resource_size_t phys_addr, |
| unsigned long size, unsigned long prot_val, void *caller) |
| { |
| unsigned long pfn, offset, vaddr; |
| resource_size_t last_addr; |
| const resource_size_t unaligned_phys_addr = phys_addr; |
| const unsigned long unaligned_size = size; |
| struct vm_struct *area; |
| unsigned long new_prot_val; |
| pgprot_t prot; |
| int retval; |
| void __iomem *ret_addr; |
| |
| /* Don't allow wraparound or zero size */ |
| last_addr = phys_addr + size - 1; |
| if (!size || last_addr < phys_addr) |
| return NULL; |
| |
| if (!phys_addr_valid(phys_addr)) { |
| printk(KERN_WARNING "ioremap: invalid physical address %llx\n", |
| (unsigned long long)phys_addr); |
| WARN_ON_ONCE(1); |
| return NULL; |
| } |
| |
| /* |
| * Don't remap the low PCI/ISA area, it's always mapped.. |
| */ |
| if (is_ISA_range(phys_addr, last_addr)) |
| return (__force void __iomem *)phys_to_virt(phys_addr); |
| |
| /* |
| * Don't allow anybody to remap normal RAM that we're using.. |
| */ |
| for (pfn = phys_addr >> PAGE_SHIFT; |
| (pfn << PAGE_SHIFT) < (last_addr & PAGE_MASK); |
| pfn++) { |
| |
| int is_ram = page_is_ram(pfn); |
| |
| if (is_ram && pfn_valid(pfn) && !PageReserved(pfn_to_page(pfn))) |
| return NULL; |
| WARN_ON_ONCE(is_ram); |
| } |
| |
| /* |
| * Mappings have to be page-aligned |
| */ |
| offset = phys_addr & ~PAGE_MASK; |
| phys_addr &= PAGE_MASK; |
| size = PAGE_ALIGN(last_addr+1) - phys_addr; |
| |
| retval = reserve_memtype(phys_addr, (u64)phys_addr + size, |
| prot_val, &new_prot_val); |
| if (retval) { |
| pr_debug("Warning: reserve_memtype returned %d\n", retval); |
| return NULL; |
| } |
| |
| if (prot_val != new_prot_val) { |
| /* |
| * Do not fallback to certain memory types with certain |
| * requested type: |
| * - request is uc-, return cannot be write-back |
| * - request is uc-, return cannot be write-combine |
| * - request is write-combine, return cannot be write-back |
| */ |
| if ((prot_val == _PAGE_CACHE_UC_MINUS && |
| (new_prot_val == _PAGE_CACHE_WB || |
| new_prot_val == _PAGE_CACHE_WC)) || |
| (prot_val == _PAGE_CACHE_WC && |
| new_prot_val == _PAGE_CACHE_WB)) { |
| pr_debug( |
| "ioremap error for 0x%llx-0x%llx, requested 0x%lx, got 0x%lx\n", |
| (unsigned long long)phys_addr, |
| (unsigned long long)(phys_addr + size), |
| prot_val, new_prot_val); |
| free_memtype(phys_addr, phys_addr + size); |
| return NULL; |
| } |
| prot_val = new_prot_val; |
| } |
| |
| switch (prot_val) { |
| case _PAGE_CACHE_UC: |
| default: |
| prot = PAGE_KERNEL_NOCACHE; |
| break; |
| case _PAGE_CACHE_UC_MINUS: |
| prot = PAGE_KERNEL_UC_MINUS; |
| break; |
| case _PAGE_CACHE_WC: |
| prot = PAGE_KERNEL_WC; |
| break; |
| case _PAGE_CACHE_WB: |
| prot = PAGE_KERNEL; |
| break; |
| } |
| |
| /* |
| * Ok, go for it.. |
| */ |
| area = get_vm_area_caller(size, VM_IOREMAP, caller); |
| if (!area) |
| return NULL; |
| area->phys_addr = phys_addr; |
| vaddr = (unsigned long) area->addr; |
| if (ioremap_page_range(vaddr, vaddr + size, phys_addr, prot)) { |
| free_memtype(phys_addr, phys_addr + size); |
| free_vm_area(area); |
| return NULL; |
| } |
| |
| if (ioremap_change_attr(vaddr, size, prot_val) < 0) { |
| free_memtype(phys_addr, phys_addr + size); |
| vunmap(area->addr); |
| return NULL; |
| } |
| |
| ret_addr = (void __iomem *) (vaddr + offset); |
| mmiotrace_ioremap(unaligned_phys_addr, unaligned_size, ret_addr); |
| |
| return ret_addr; |
| } |
| |
| /** |
| * ioremap_nocache - map bus memory into CPU space |
| * @offset: bus address of the memory |
| * @size: size of the resource to map |
| * |
| * ioremap_nocache performs a platform specific sequence of operations to |
| * make bus memory CPU accessible via the readb/readw/readl/writeb/ |
| * writew/writel functions and the other mmio helpers. The returned |
| * address is not guaranteed to be usable directly as a virtual |
| * address. |
| * |
| * This version of ioremap ensures that the memory is marked uncachable |
| * on the CPU as well as honouring existing caching rules from things like |
| * the PCI bus. Note that there are other caches and buffers on many |
| * busses. In particular driver authors should read up on PCI writes |
| * |
| * It's useful if some control registers are in such an area and |
| * write combining or read caching is not desirable: |
| * |
| * Must be freed with iounmap. |
| */ |
| void __iomem *ioremap_nocache(resource_size_t phys_addr, unsigned long size) |
| { |
| /* |
| * Ideally, this should be: |
| * pat_enabled ? _PAGE_CACHE_UC : _PAGE_CACHE_UC_MINUS; |
| * |
| * Till we fix all X drivers to use ioremap_wc(), we will use |
| * UC MINUS. |
| */ |
| unsigned long val = _PAGE_CACHE_UC_MINUS; |
| |
| return __ioremap_caller(phys_addr, size, val, |
| __builtin_return_address(0)); |
| } |
| EXPORT_SYMBOL(ioremap_nocache); |
| |
| /** |
| * ioremap_wc - map memory into CPU space write combined |
| * @offset: bus address of the memory |
| * @size: size of the resource to map |
| * |
| * This version of ioremap ensures that the memory is marked write combining. |
| * Write combining allows faster writes to some hardware devices. |
| * |
| * Must be freed with iounmap. |
| */ |
| void __iomem *ioremap_wc(unsigned long phys_addr, unsigned long size) |
| { |
| if (pat_enabled) |
| return __ioremap_caller(phys_addr, size, _PAGE_CACHE_WC, |
| __builtin_return_address(0)); |
| else |
| return ioremap_nocache(phys_addr, size); |
| } |
| EXPORT_SYMBOL(ioremap_wc); |
| |
| void __iomem *ioremap_cache(resource_size_t phys_addr, unsigned long size) |
| { |
| return __ioremap_caller(phys_addr, size, _PAGE_CACHE_WB, |
| __builtin_return_address(0)); |
| } |
| EXPORT_SYMBOL(ioremap_cache); |
| |
| static void __iomem *ioremap_default(resource_size_t phys_addr, |
| unsigned long size) |
| { |
| unsigned long flags; |
| void *ret; |
| int err; |
| |
| /* |
| * - WB for WB-able memory and no other conflicting mappings |
| * - UC_MINUS for non-WB-able memory with no other conflicting mappings |
| * - Inherit from confliting mappings otherwise |
| */ |
| err = reserve_memtype(phys_addr, phys_addr + size, -1, &flags); |
| if (err < 0) |
| return NULL; |
| |
| ret = (void *) __ioremap_caller(phys_addr, size, flags, |
| __builtin_return_address(0)); |
| |
| free_memtype(phys_addr, phys_addr + size); |
| return (void __iomem *)ret; |
| } |
| |
| void __iomem *ioremap_prot(resource_size_t phys_addr, unsigned long size, |
| unsigned long prot_val) |
| { |
| return __ioremap_caller(phys_addr, size, (prot_val & _PAGE_CACHE_MASK), |
| __builtin_return_address(0)); |
| } |
| EXPORT_SYMBOL(ioremap_prot); |
| |
| /** |
| * iounmap - Free a IO remapping |
| * @addr: virtual address from ioremap_* |
| * |
| * Caller must ensure there is only one unmapping for the same pointer. |
| */ |
| void iounmap(volatile void __iomem *addr) |
| { |
| struct vm_struct *p, *o; |
| |
| if ((void __force *)addr <= high_memory) |
| return; |
| |
| /* |
| * __ioremap special-cases the PCI/ISA range by not instantiating a |
| * vm_area and by simply returning an address into the kernel mapping |
| * of ISA space. So handle that here. |
| */ |
| if ((void __force *)addr >= phys_to_virt(ISA_START_ADDRESS) && |
| (void __force *)addr < phys_to_virt(ISA_END_ADDRESS)) |
| return; |
| |
| addr = (volatile void __iomem *) |
| (PAGE_MASK & (unsigned long __force)addr); |
| |
| mmiotrace_iounmap(addr); |
| |
| /* Use the vm area unlocked, assuming the caller |
| ensures there isn't another iounmap for the same address |
| in parallel. Reuse of the virtual address is prevented by |
| leaving it in the global lists until we're done with it. |
| cpa takes care of the direct mappings. */ |
| read_lock(&vmlist_lock); |
| for (p = vmlist; p; p = p->next) { |
| if (p->addr == (void __force *)addr) |
| break; |
| } |
| read_unlock(&vmlist_lock); |
| |
| if (!p) { |
| printk(KERN_ERR "iounmap: bad address %p\n", addr); |
| dump_stack(); |
| return; |
| } |
| |
| free_memtype(p->phys_addr, p->phys_addr + get_vm_area_size(p)); |
| |
| /* Finally remove it */ |
| o = remove_vm_area((void __force *)addr); |
| BUG_ON(p != o || o == NULL); |
| kfree(p); |
| } |
| EXPORT_SYMBOL(iounmap); |
| |
| /* |
| * Convert a physical pointer to a virtual kernel pointer for /dev/mem |
| * access |
| */ |
| void *xlate_dev_mem_ptr(unsigned long phys) |
| { |
| void *addr; |
| unsigned long start = phys & PAGE_MASK; |
| |
| /* If page is RAM, we can use __va. Otherwise ioremap and unmap. */ |
| if (page_is_ram(start >> PAGE_SHIFT)) |
| return __va(phys); |
| |
| addr = (void __force *)ioremap_default(start, PAGE_SIZE); |
| if (addr) |
| addr = (void *)((unsigned long)addr | (phys & ~PAGE_MASK)); |
| |
| return addr; |
| } |
| |
| void unxlate_dev_mem_ptr(unsigned long phys, void *addr) |
| { |
| if (page_is_ram(phys >> PAGE_SHIFT)) |
| return; |
| |
| iounmap((void __iomem *)((unsigned long)addr & PAGE_MASK)); |
| return; |
| } |
| |
| static int __initdata early_ioremap_debug; |
| |
| static int __init early_ioremap_debug_setup(char *str) |
| { |
| early_ioremap_debug = 1; |
| |
| return 0; |
| } |
| early_param("early_ioremap_debug", early_ioremap_debug_setup); |
| |
| static __initdata int after_paging_init; |
| static pte_t bm_pte[PAGE_SIZE/sizeof(pte_t)] __page_aligned_bss; |
| |
| static inline pmd_t * __init early_ioremap_pmd(unsigned long addr) |
| { |
| /* Don't assume we're using swapper_pg_dir at this point */ |
| pgd_t *base = __va(read_cr3()); |
| pgd_t *pgd = &base[pgd_index(addr)]; |
| pud_t *pud = pud_offset(pgd, addr); |
| pmd_t *pmd = pmd_offset(pud, addr); |
| |
| return pmd; |
| } |
| |
| static inline pte_t * __init early_ioremap_pte(unsigned long addr) |
| { |
| return &bm_pte[pte_index(addr)]; |
| } |
| |
| void __init early_ioremap_init(void) |
| { |
| pmd_t *pmd; |
| |
| if (early_ioremap_debug) |
| printk(KERN_INFO "early_ioremap_init()\n"); |
| |
| pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)); |
| memset(bm_pte, 0, sizeof(bm_pte)); |
| pmd_populate_kernel(&init_mm, pmd, bm_pte); |
| |
| /* |
| * The boot-ioremap range spans multiple pmds, for which |
| * we are not prepared: |
| */ |
| if (pmd != early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))) { |
| WARN_ON(1); |
| printk(KERN_WARNING "pmd %p != %p\n", |
| pmd, early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))); |
| printk(KERN_WARNING "fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n", |
| fix_to_virt(FIX_BTMAP_BEGIN)); |
| printk(KERN_WARNING "fix_to_virt(FIX_BTMAP_END): %08lx\n", |
| fix_to_virt(FIX_BTMAP_END)); |
| |
| printk(KERN_WARNING "FIX_BTMAP_END: %d\n", FIX_BTMAP_END); |
| printk(KERN_WARNING "FIX_BTMAP_BEGIN: %d\n", |
| FIX_BTMAP_BEGIN); |
| } |
| } |
| |
| void __init early_ioremap_clear(void) |
| { |
| pmd_t *pmd; |
| |
| if (early_ioremap_debug) |
| printk(KERN_INFO "early_ioremap_clear()\n"); |
| |
| pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)); |
| pmd_clear(pmd); |
| paravirt_release_pte(__pa(bm_pte) >> PAGE_SHIFT); |
| __flush_tlb_all(); |
| } |
| |
| void __init early_ioremap_reset(void) |
| { |
| enum fixed_addresses idx; |
| unsigned long addr, phys; |
| pte_t *pte; |
| |
| after_paging_init = 1; |
| for (idx = FIX_BTMAP_BEGIN; idx >= FIX_BTMAP_END; idx--) { |
| addr = fix_to_virt(idx); |
| pte = early_ioremap_pte(addr); |
| if (pte_present(*pte)) { |
| phys = pte_val(*pte) & PAGE_MASK; |
| set_fixmap(idx, phys); |
| } |
| } |
| } |
| |
| static void __init __early_set_fixmap(enum fixed_addresses idx, |
| unsigned long phys, pgprot_t flags) |
| { |
| unsigned long addr = __fix_to_virt(idx); |
| pte_t *pte; |
| |
| if (idx >= __end_of_fixed_addresses) { |
| BUG(); |
| return; |
| } |
| pte = early_ioremap_pte(addr); |
| |
| if (pgprot_val(flags)) |
| set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, flags)); |
| else |
| pte_clear(&init_mm, addr, pte); |
| __flush_tlb_one(addr); |
| } |
| |
| static inline void __init early_set_fixmap(enum fixed_addresses idx, |
| unsigned long phys) |
| { |
| if (after_paging_init) |
| set_fixmap(idx, phys); |
| else |
| __early_set_fixmap(idx, phys, PAGE_KERNEL); |
| } |
| |
| static inline void __init early_clear_fixmap(enum fixed_addresses idx) |
| { |
| if (after_paging_init) |
| clear_fixmap(idx); |
| else |
| __early_set_fixmap(idx, 0, __pgprot(0)); |
| } |
| |
| |
| static int __initdata early_ioremap_nested; |
| |
| static int __init check_early_ioremap_leak(void) |
| { |
| if (!early_ioremap_nested) |
| return 0; |
| WARN(1, KERN_WARNING |
| "Debug warning: early ioremap leak of %d areas detected.\n", |
| early_ioremap_nested); |
| printk(KERN_WARNING |
| "please boot with early_ioremap_debug and report the dmesg.\n"); |
| |
| return 1; |
| } |
| late_initcall(check_early_ioremap_leak); |
| |
| void __init *early_ioremap(unsigned long phys_addr, unsigned long size) |
| { |
| unsigned long offset, last_addr; |
| unsigned int nrpages, nesting; |
| enum fixed_addresses idx0, idx; |
| |
| WARN_ON(system_state != SYSTEM_BOOTING); |
| |
| nesting = early_ioremap_nested; |
| if (early_ioremap_debug) { |
| printk(KERN_INFO "early_ioremap(%08lx, %08lx) [%d] => ", |
| phys_addr, size, nesting); |
| dump_stack(); |
| } |
| |
| /* Don't allow wraparound or zero size */ |
| last_addr = phys_addr + size - 1; |
| if (!size || last_addr < phys_addr) { |
| WARN_ON(1); |
| return NULL; |
| } |
| |
| if (nesting >= FIX_BTMAPS_NESTING) { |
| WARN_ON(1); |
| return NULL; |
| } |
| early_ioremap_nested++; |
| /* |
| * Mappings have to be page-aligned |
| */ |
| offset = phys_addr & ~PAGE_MASK; |
| phys_addr &= PAGE_MASK; |
| size = PAGE_ALIGN(last_addr) - phys_addr; |
| |
| /* |
| * Mappings have to fit in the FIX_BTMAP area. |
| */ |
| nrpages = size >> PAGE_SHIFT; |
| if (nrpages > NR_FIX_BTMAPS) { |
| WARN_ON(1); |
| return NULL; |
| } |
| |
| /* |
| * Ok, go for it.. |
| */ |
| idx0 = FIX_BTMAP_BEGIN - NR_FIX_BTMAPS*nesting; |
| idx = idx0; |
| while (nrpages > 0) { |
| early_set_fixmap(idx, phys_addr); |
| phys_addr += PAGE_SIZE; |
| --idx; |
| --nrpages; |
| } |
| if (early_ioremap_debug) |
| printk(KERN_CONT "%08lx + %08lx\n", offset, fix_to_virt(idx0)); |
| |
| return (void *) (offset + fix_to_virt(idx0)); |
| } |
| |
| void __init early_iounmap(void *addr, unsigned long size) |
| { |
| unsigned long virt_addr; |
| unsigned long offset; |
| unsigned int nrpages; |
| enum fixed_addresses idx; |
| int nesting; |
| |
| nesting = --early_ioremap_nested; |
| if (WARN_ON(nesting < 0)) |
| return; |
| |
| if (early_ioremap_debug) { |
| printk(KERN_INFO "early_iounmap(%p, %08lx) [%d]\n", addr, |
| size, nesting); |
| dump_stack(); |
| } |
| |
| virt_addr = (unsigned long)addr; |
| if (virt_addr < fix_to_virt(FIX_BTMAP_BEGIN)) { |
| WARN_ON(1); |
| return; |
| } |
| offset = virt_addr & ~PAGE_MASK; |
| nrpages = PAGE_ALIGN(offset + size - 1) >> PAGE_SHIFT; |
| |
| idx = FIX_BTMAP_BEGIN - NR_FIX_BTMAPS*nesting; |
| while (nrpages > 0) { |
| early_clear_fixmap(idx); |
| --idx; |
| --nrpages; |
| } |
| } |
| |
| void __this_fixmap_does_not_exist(void) |
| { |
| WARN_ON(1); |
| } |