diff options
Diffstat (limited to 'arch/unicore32/mm/ioremap.c')
-rw-r--r-- | arch/unicore32/mm/ioremap.c | 242 |
1 files changed, 0 insertions, 242 deletions
diff --git a/arch/unicore32/mm/ioremap.c b/arch/unicore32/mm/ioremap.c deleted file mode 100644 index 46a64bd6156a..000000000000 --- a/arch/unicore32/mm/ioremap.c +++ /dev/null @@ -1,242 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * linux/arch/unicore32/mm/ioremap.c - * - * Code specific to PKUnity SoC and UniCore ISA - * - * Copyright (C) 2001-2010 GUAN Xue-tao - * - * Re-map IO memory to kernel address space so that we can access it. - * - * This allows a driver to remap an arbitrary region of bus memory into - * virtual space. One should *only* use readl, writel, memcpy_toio and - * so on with such remapped areas. - * - * Because UniCore only has a 32-bit address space we can't address the - * whole of the (physical) PCI space at once. PCI huge-mode addressing - * allows us to circumvent this restriction by splitting PCI space into - * two 2GB chunks and mapping only one at a time into processor memory. - * We use MMU protection domains to trap any attempt to access the bank - * that is not currently mapped. (This isn't fully implemented yet.) - */ -#include <linux/module.h> -#include <linux/errno.h> -#include <linux/mm.h> -#include <linux/vmalloc.h> -#include <linux/io.h> - -#include <asm/cputype.h> -#include <asm/cacheflush.h> -#include <asm/mmu_context.h> -#include <asm/pgalloc.h> -#include <asm/tlbflush.h> -#include <linux/sizes.h> - -#include <mach/map.h> -#include "mm.h" - -/* - * Used by ioremap() and iounmap() code to mark (super)section-mapped - * I/O regions in vm_struct->flags field. - */ -#define VM_UNICORE_SECTION_MAPPING 0x80000000 - -int ioremap_page(unsigned long virt, unsigned long phys, - const struct mem_type *mtype) -{ - return ioremap_page_range(virt, virt + PAGE_SIZE, phys, - __pgprot(mtype->prot_pte)); -} -EXPORT_SYMBOL(ioremap_page); - -/* - * Section support is unsafe on SMP - If you iounmap and ioremap a region, - * the other CPUs will not see this change until their next context switch. - * Meanwhile, (eg) if an interrupt comes in on one of those other CPUs - * which requires the new ioremap'd region to be referenced, the CPU will - * reference the _old_ region. - * - * Note that get_vm_area_caller() allocates a guard 4K page, so we need to - * mask the size back to 4MB aligned or we will overflow in the loop below. - */ -static void unmap_area_sections(unsigned long virt, unsigned long size) -{ - unsigned long addr = virt, end = virt + (size & ~(SZ_4M - 1)); - pgd_t *pgd; - - flush_cache_vunmap(addr, end); - pgd = pgd_offset_k(addr); - do { - pmd_t pmd, *pmdp = pmd_offset((pud_t *)pgd, addr); - - pmd = *pmdp; - if (!pmd_none(pmd)) { - /* - * Clear the PMD from the page table, and - * increment the kvm sequence so others - * notice this change. - * - * Note: this is still racy on SMP machines. - */ - pmd_clear(pmdp); - - /* - * Free the page table, if there was one. - */ - if ((pmd_val(pmd) & PMD_TYPE_MASK) == PMD_TYPE_TABLE) - pte_free_kernel(&init_mm, pmd_page_vaddr(pmd)); - } - - addr += PGDIR_SIZE; - pgd++; - } while (addr < end); - - flush_tlb_kernel_range(virt, end); -} - -static int -remap_area_sections(unsigned long virt, unsigned long pfn, - size_t size, const struct mem_type *type) -{ - unsigned long addr = virt, end = virt + size; - pgd_t *pgd; - - /* - * Remove and free any PTE-based mapping, and - * sync the current kernel mapping. - */ - unmap_area_sections(virt, size); - - pgd = pgd_offset_k(addr); - do { - pmd_t *pmd = pmd_offset((pud_t *)pgd, addr); - - set_pmd(pmd, __pmd(__pfn_to_phys(pfn) | type->prot_sect)); - pfn += SZ_4M >> PAGE_SHIFT; - flush_pmd_entry(pmd); - - addr += PGDIR_SIZE; - pgd++; - } while (addr < end); - - return 0; -} - -void __iomem *__uc32_ioremap_pfn_caller(unsigned long pfn, - unsigned long offset, size_t size, unsigned int mtype, void *caller) -{ - const struct mem_type *type; - int err; - unsigned long addr; - struct vm_struct *area; - - /* - * High mappings must be section aligned - */ - if (pfn >= 0x100000 && (__pfn_to_phys(pfn) & ~SECTION_MASK)) - return NULL; - - /* - * Don't allow RAM to be mapped - */ - if (pfn_valid(pfn)) { - WARN(1, "BUG: Your driver calls ioremap() on\n" - "system memory. This leads to architecturally\n" - "unpredictable behaviour, and ioremap() will fail in\n" - "the next kernel release. Please fix your driver.\n"); - return NULL; - } - - type = get_mem_type(mtype); - if (!type) - return NULL; - - /* - * Page align the mapping size, taking account of any offset. - */ - size = PAGE_ALIGN(offset + size); - - area = get_vm_area_caller(size, VM_IOREMAP, caller); - if (!area) - return NULL; - addr = (unsigned long)area->addr; - - if (!((__pfn_to_phys(pfn) | size | addr) & ~PMD_MASK)) { - area->flags |= VM_UNICORE_SECTION_MAPPING; - err = remap_area_sections(addr, pfn, size, type); - } else - err = ioremap_page_range(addr, addr + size, __pfn_to_phys(pfn), - __pgprot(type->prot_pte)); - - if (err) { - vunmap((void *)addr); - return NULL; - } - - flush_cache_vmap(addr, addr + size); - return (void __iomem *) (offset + addr); -} - -void __iomem *__uc32_ioremap_caller(unsigned long phys_addr, size_t size, - unsigned int mtype, void *caller) -{ - unsigned long last_addr; - unsigned long offset = phys_addr & ~PAGE_MASK; - unsigned long pfn = __phys_to_pfn(phys_addr); - - /* - * Don't allow wraparound or zero size - */ - last_addr = phys_addr + size - 1; - if (!size || last_addr < phys_addr) - return NULL; - - return __uc32_ioremap_pfn_caller(pfn, offset, size, mtype, caller); -} - -/* - * 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. - */ -void __iomem * -__uc32_ioremap_pfn(unsigned long pfn, unsigned long offset, size_t size, - unsigned int mtype) -{ - return __uc32_ioremap_pfn_caller(pfn, offset, size, mtype, - __builtin_return_address(0)); -} -EXPORT_SYMBOL(__uc32_ioremap_pfn); - -void __iomem * -__uc32_ioremap(unsigned long phys_addr, size_t size) -{ - return __uc32_ioremap_caller(phys_addr, size, MT_DEVICE, - __builtin_return_address(0)); -} -EXPORT_SYMBOL(__uc32_ioremap); - -void __uc32_iounmap(volatile void __iomem *io_addr) -{ - void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr); - struct vm_struct *vm; - - /* - * If this is a section based mapping we need to handle it - * specially as the VM subsystem does not know how to handle - * such a beast. We need the lock here b/c we need to clear - * all the mappings before the area can be reclaimed - * by someone else. - */ - vm = find_vm_area(addr); - if (vm && (vm->flags & VM_IOREMAP) && - (vm->flags & VM_UNICORE_SECTION_MAPPING)) - unmap_area_sections((unsigned long)vm->addr, vm->size); - - vunmap(addr); -} -EXPORT_SYMBOL(__uc32_iounmap); |