| /* |
| * 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> |
| |
| #include "physaddr.h" |
| |
| /* |
| * Fix up the linear direct mapping of the kernel to avoid cache attribute |
| * conflicts. |
| */ |
| int ioremap_change_attr(unsigned long vaddr, unsigned long size, |
| enum page_cache_mode pcm) |
| { |
| unsigned long nrpages = size >> PAGE_SHIFT; |
| int err; |
| |
| switch (pcm) { |
| case _PAGE_CACHE_MODE_UC: |
| default: |
| err = _set_memory_uc(vaddr, nrpages); |
| break; |
| case _PAGE_CACHE_MODE_WC: |
| err = _set_memory_wc(vaddr, nrpages); |
| break; |
| case _PAGE_CACHE_MODE_WB: |
| err = _set_memory_wb(vaddr, nrpages); |
| break; |
| } |
| |
| return err; |
| } |
| |
| static int __ioremap_check_ram(unsigned long start_pfn, unsigned long nr_pages, |
| void *arg) |
| { |
| unsigned long i; |
| |
| for (i = 0; i < nr_pages; ++i) |
| if (pfn_valid(start_pfn + i) && |
| !PageReserved(pfn_to_page(start_pfn + i))) |
| return 1; |
| |
| WARN_ONCE(1, "ioremap on RAM pfn 0x%lx\n", start_pfn); |
| |
| return 0; |
| } |
| |
| /* |
| * 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, enum page_cache_mode pcm, void *caller) |
| { |
| unsigned long offset, vaddr; |
| resource_size_t pfn, last_pfn, last_addr; |
| const resource_size_t unaligned_phys_addr = phys_addr; |
| const unsigned long unaligned_size = size; |
| struct vm_struct *area; |
| enum page_cache_mode new_pcm; |
| pgprot_t prot; |
| int retval; |
| void __iomem *ret_addr; |
| int ram_region; |
| |
| /* 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.. |
| */ |
| /* First check if whole region can be identified as RAM or not */ |
| ram_region = region_is_ram(phys_addr, size); |
| if (ram_region > 0) { |
| WARN_ONCE(1, "ioremap on RAM at 0x%lx - 0x%lx\n", |
| (unsigned long int)phys_addr, |
| (unsigned long int)last_addr); |
| return NULL; |
| } |
| |
| /* If could not be identified(-1), check page by page */ |
| if (ram_region < 0) { |
| pfn = phys_addr >> PAGE_SHIFT; |
| last_pfn = last_addr >> PAGE_SHIFT; |
| if (walk_system_ram_range(pfn, last_pfn - pfn + 1, NULL, |
| __ioremap_check_ram) == 1) |
| return NULL; |
| } |
| /* |
| * Mappings have to be page-aligned |
| */ |
| offset = phys_addr & ~PAGE_MASK; |
| phys_addr &= PHYSICAL_PAGE_MASK; |
| size = PAGE_ALIGN(last_addr+1) - phys_addr; |
| |
| retval = reserve_memtype(phys_addr, (u64)phys_addr + size, |
| pcm, &new_pcm); |
| if (retval) { |
| printk(KERN_ERR "ioremap reserve_memtype failed %d\n", retval); |
| return NULL; |
| } |
| |
| if (pcm != new_pcm) { |
| if (!is_new_memtype_allowed(phys_addr, size, pcm, new_pcm)) { |
| printk(KERN_ERR |
| "ioremap error for 0x%llx-0x%llx, requested 0x%x, got 0x%x\n", |
| (unsigned long long)phys_addr, |
| (unsigned long long)(phys_addr + size), |
| pcm, new_pcm); |
| goto err_free_memtype; |
| } |
| pcm = new_pcm; |
| } |
| |
| prot = PAGE_KERNEL_IO; |
| switch (pcm) { |
| case _PAGE_CACHE_MODE_UC: |
| default: |
| prot = __pgprot(pgprot_val(prot) | |
| cachemode2protval(_PAGE_CACHE_MODE_UC)); |
| break; |
| case _PAGE_CACHE_MODE_UC_MINUS: |
| prot = __pgprot(pgprot_val(prot) | |
| cachemode2protval(_PAGE_CACHE_MODE_UC_MINUS)); |
| break; |
| case _PAGE_CACHE_MODE_WC: |
| prot = __pgprot(pgprot_val(prot) | |
| cachemode2protval(_PAGE_CACHE_MODE_WC)); |
| break; |
| case _PAGE_CACHE_MODE_WB: |
| break; |
| } |
| |
| /* |
| * Ok, go for it.. |
| */ |
| area = get_vm_area_caller(size, VM_IOREMAP, caller); |
| if (!area) |
| goto err_free_memtype; |
| area->phys_addr = phys_addr; |
| vaddr = (unsigned long) area->addr; |
| |
| if (kernel_map_sync_memtype(phys_addr, size, pcm)) |
| goto err_free_area; |
| |
| if (ioremap_page_range(vaddr, vaddr + size, phys_addr, prot)) |
| goto err_free_area; |
| |
| ret_addr = (void __iomem *) (vaddr + offset); |
| mmiotrace_ioremap(unaligned_phys_addr, unaligned_size, ret_addr); |
| |
| /* |
| * Check if the request spans more than any BAR in the iomem resource |
| * tree. |
| */ |
| WARN_ONCE(iomem_map_sanity_check(unaligned_phys_addr, unaligned_size), |
| KERN_INFO "Info: mapping multiple BARs. Your kernel is fine."); |
| |
| return ret_addr; |
| err_free_area: |
| free_vm_area(area); |
| err_free_memtype: |
| free_memtype(phys_addr, phys_addr + size); |
| return NULL; |
| } |
| |
| /** |
| * ioremap_nocache - map bus memory into CPU space |
| * @phys_addr: 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_MODE_UC : _PAGE_CACHE_MODE_UC_MINUS; |
| * |
| * Till we fix all X drivers to use ioremap_wc(), we will use |
| * UC MINUS. |
| */ |
| enum page_cache_mode pcm = _PAGE_CACHE_MODE_UC_MINUS; |
| |
| return __ioremap_caller(phys_addr, size, pcm, |
| __builtin_return_address(0)); |
| } |
| EXPORT_SYMBOL(ioremap_nocache); |
| |
| /** |
| * ioremap_wc - map memory into CPU space write combined |
| * @phys_addr: 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(resource_size_t phys_addr, unsigned long size) |
| { |
| if (pat_enabled) |
| return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_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_MODE_WB, |
| __builtin_return_address(0)); |
| } |
| EXPORT_SYMBOL(ioremap_cache); |
| |
| void __iomem *ioremap_prot(resource_size_t phys_addr, unsigned long size, |
| unsigned long prot_val) |
| { |
| return __ioremap_caller(phys_addr, size, |
| pgprot2cachemode(__pgprot(prot_val)), |
| __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. */ |
| p = find_vm_area((void __force *)addr); |
| |
| 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(phys_addr_t phys) |
| { |
| unsigned long start = phys & PAGE_MASK; |
| unsigned long offset = phys & ~PAGE_MASK; |
| unsigned long vaddr; |
| |
| /* If page is RAM, we can use __va. Otherwise ioremap and unmap. */ |
| if (page_is_ram(start >> PAGE_SHIFT)) |
| return __va(phys); |
| |
| vaddr = (unsigned long)ioremap_cache(start, PAGE_SIZE); |
| /* Only add the offset on success and return NULL if the ioremap() failed: */ |
| if (vaddr) |
| vaddr += offset; |
| |
| return (void *)vaddr; |
| } |
| |
| void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr) |
| { |
| if (page_is_ram(phys >> PAGE_SHIFT)) |
| return; |
| |
| iounmap((void __iomem *)((unsigned long)addr & PAGE_MASK)); |
| return; |
| } |
| |
| 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)]; |
| } |
| |
| bool __init is_early_ioremap_ptep(pte_t *ptep) |
| { |
| return ptep >= &bm_pte[0] && ptep < &bm_pte[PAGE_SIZE/sizeof(pte_t)]; |
| } |
| |
| void __init early_ioremap_init(void) |
| { |
| pmd_t *pmd; |
| |
| #ifdef CONFIG_X86_64 |
| BUILD_BUG_ON((fix_to_virt(0) + PAGE_SIZE) & ((1 << PMD_SHIFT) - 1)); |
| #else |
| WARN_ON((fix_to_virt(0) + PAGE_SIZE) & ((1 << PMD_SHIFT) - 1)); |
| #endif |
| |
| early_ioremap_setup(); |
| |
| 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: |
| */ |
| #define __FIXADDR_TOP (-PAGE_SIZE) |
| BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT) |
| != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT)); |
| #undef __FIXADDR_TOP |
| 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_set_fixmap(enum fixed_addresses idx, |
| phys_addr_t 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); |
| } |