v4.19.13 snapshot.
diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c
new file mode 100644
index 0000000..5bf9443
--- /dev/null
+++ b/arch/arm/mm/ioremap.c
@@ -0,0 +1,499 @@
+/*
+ * linux/arch/arm/mm/ioremap.c
+ *
+ * Re-map IO memory to kernel address space so that we can access it.
+ *
+ * (C) Copyright 1995 1996 Linus Torvalds
+ *
+ * Hacked for ARM by Phil Blundell <philb@gnu.org>
+ * Hacked to allow all architectures to build, and various cleanups
+ * by Russell King
+ *
+ * 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 the ARM 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 <linux/sizes.h>
+
+#include <asm/cp15.h>
+#include <asm/cputype.h>
+#include <asm/cacheflush.h>
+#include <asm/early_ioremap.h>
+#include <asm/mmu_context.h>
+#include <asm/pgalloc.h>
+#include <asm/tlbflush.h>
+#include <asm/system_info.h>
+
+#include <asm/mach/map.h>
+#include <asm/mach/pci.h>
+#include "mm.h"
+
+
+LIST_HEAD(static_vmlist);
+
+static struct static_vm *find_static_vm_paddr(phys_addr_t paddr,
+ size_t size, unsigned int mtype)
+{
+ struct static_vm *svm;
+ struct vm_struct *vm;
+
+ list_for_each_entry(svm, &static_vmlist, list) {
+ vm = &svm->vm;
+ if (!(vm->flags & VM_ARM_STATIC_MAPPING))
+ continue;
+ if ((vm->flags & VM_ARM_MTYPE_MASK) != VM_ARM_MTYPE(mtype))
+ continue;
+
+ if (vm->phys_addr > paddr ||
+ paddr + size - 1 > vm->phys_addr + vm->size - 1)
+ continue;
+
+ return svm;
+ }
+
+ return NULL;
+}
+
+struct static_vm *find_static_vm_vaddr(void *vaddr)
+{
+ struct static_vm *svm;
+ struct vm_struct *vm;
+
+ list_for_each_entry(svm, &static_vmlist, list) {
+ vm = &svm->vm;
+
+ /* static_vmlist is ascending order */
+ if (vm->addr > vaddr)
+ break;
+
+ if (vm->addr <= vaddr && vm->addr + vm->size > vaddr)
+ return svm;
+ }
+
+ return NULL;
+}
+
+void __init add_static_vm_early(struct static_vm *svm)
+{
+ struct static_vm *curr_svm;
+ struct vm_struct *vm;
+ void *vaddr;
+
+ vm = &svm->vm;
+ vm_area_add_early(vm);
+ vaddr = vm->addr;
+
+ list_for_each_entry(curr_svm, &static_vmlist, list) {
+ vm = &curr_svm->vm;
+
+ if (vm->addr > vaddr)
+ break;
+ }
+ list_add_tail(&svm->list, &curr_svm->list);
+}
+
+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);
+
+void __check_vmalloc_seq(struct mm_struct *mm)
+{
+ unsigned int seq;
+
+ do {
+ seq = init_mm.context.vmalloc_seq;
+ memcpy(pgd_offset(mm, VMALLOC_START),
+ pgd_offset_k(VMALLOC_START),
+ sizeof(pgd_t) * (pgd_index(VMALLOC_END) -
+ pgd_index(VMALLOC_START)));
+ mm->context.vmalloc_seq = seq;
+ } while (seq != init_mm.context.vmalloc_seq);
+}
+
+#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
+/*
+ * 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 1MB 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_1M - 1));
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmdp;
+
+ flush_cache_vunmap(addr, end);
+ pgd = pgd_offset_k(addr);
+ pud = pud_offset(pgd, addr);
+ pmdp = pmd_offset(pud, addr);
+ do {
+ pmd_t pmd = *pmdp;
+
+ if (!pmd_none(pmd)) {
+ /*
+ * Clear the PMD from the page table, and
+ * increment the vmalloc sequence so others
+ * notice this change.
+ *
+ * Note: this is still racy on SMP machines.
+ */
+ pmd_clear(pmdp);
+ init_mm.context.vmalloc_seq++;
+
+ /*
+ * 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 += PMD_SIZE;
+ pmdp += 2;
+ } while (addr < end);
+
+ /*
+ * Ensure that the active_mm is up to date - we want to
+ * catch any use-after-iounmap cases.
+ */
+ if (current->active_mm->context.vmalloc_seq != init_mm.context.vmalloc_seq)
+ __check_vmalloc_seq(current->active_mm);
+
+ 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;
+ pud_t *pud;
+ pmd_t *pmd;
+
+ /*
+ * Remove and free any PTE-based mapping, and
+ * sync the current kernel mapping.
+ */
+ unmap_area_sections(virt, size);
+
+ pgd = pgd_offset_k(addr);
+ pud = pud_offset(pgd, addr);
+ pmd = pmd_offset(pud, addr);
+ do {
+ pmd[0] = __pmd(__pfn_to_phys(pfn) | type->prot_sect);
+ pfn += SZ_1M >> PAGE_SHIFT;
+ pmd[1] = __pmd(__pfn_to_phys(pfn) | type->prot_sect);
+ pfn += SZ_1M >> PAGE_SHIFT;
+ flush_pmd_entry(pmd);
+
+ addr += PMD_SIZE;
+ pmd += 2;
+ } while (addr < end);
+
+ return 0;
+}
+
+static int
+remap_area_supersections(unsigned long virt, unsigned long pfn,
+ size_t size, const struct mem_type *type)
+{
+ unsigned long addr = virt, end = virt + size;
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+
+ /*
+ * Remove and free any PTE-based mapping, and
+ * sync the current kernel mapping.
+ */
+ unmap_area_sections(virt, size);
+
+ pgd = pgd_offset_k(virt);
+ pud = pud_offset(pgd, addr);
+ pmd = pmd_offset(pud, addr);
+ do {
+ unsigned long super_pmd_val, i;
+
+ super_pmd_val = __pfn_to_phys(pfn) | type->prot_sect |
+ PMD_SECT_SUPER;
+ super_pmd_val |= ((pfn >> (32 - PAGE_SHIFT)) & 0xf) << 20;
+
+ for (i = 0; i < 8; i++) {
+ pmd[0] = __pmd(super_pmd_val);
+ pmd[1] = __pmd(super_pmd_val);
+ flush_pmd_entry(pmd);
+
+ addr += PMD_SIZE;
+ pmd += 2;
+ }
+
+ pfn += SUPERSECTION_SIZE >> PAGE_SHIFT;
+ } while (addr < end);
+
+ return 0;
+}
+#endif
+
+static void __iomem * __arm_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;
+ phys_addr_t paddr = __pfn_to_phys(pfn);
+
+#ifndef CONFIG_ARM_LPAE
+ /*
+ * High mappings must be supersection aligned
+ */
+ if (pfn >= 0x100000 && (paddr & ~SUPERSECTION_MASK))
+ return NULL;
+#endif
+
+ type = get_mem_type(mtype);
+ if (!type)
+ return NULL;
+
+ /*
+ * Page align the mapping size, taking account of any offset.
+ */
+ size = PAGE_ALIGN(offset + size);
+
+ /*
+ * Try to reuse one of the static mapping whenever possible.
+ */
+ if (size && !(sizeof(phys_addr_t) == 4 && pfn >= 0x100000)) {
+ struct static_vm *svm;
+
+ svm = find_static_vm_paddr(paddr, size, mtype);
+ if (svm) {
+ addr = (unsigned long)svm->vm.addr;
+ addr += paddr - svm->vm.phys_addr;
+ return (void __iomem *) (offset + addr);
+ }
+ }
+
+ /*
+ * Don't allow RAM to be mapped with mismatched attributes - this
+ * causes problems with ARMv6+
+ */
+ if (WARN_ON(pfn_valid(pfn) && mtype != MT_MEMORY_RW))
+ return NULL;
+
+ area = get_vm_area_caller(size, VM_IOREMAP, caller);
+ if (!area)
+ return NULL;
+ addr = (unsigned long)area->addr;
+ area->phys_addr = paddr;
+
+#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
+ if (DOMAIN_IO == 0 &&
+ (((cpu_architecture() >= CPU_ARCH_ARMv6) && (get_cr() & CR_XP)) ||
+ cpu_is_xsc3()) && pfn >= 0x100000 &&
+ !((paddr | size | addr) & ~SUPERSECTION_MASK)) {
+ area->flags |= VM_ARM_SECTION_MAPPING;
+ err = remap_area_supersections(addr, pfn, size, type);
+ } else if (!((paddr | size | addr) & ~PMD_MASK)) {
+ area->flags |= VM_ARM_SECTION_MAPPING;
+ err = remap_area_sections(addr, pfn, size, type);
+ } else
+#endif
+ err = ioremap_page_range(addr, addr + size, paddr,
+ __pgprot(type->prot_pte));
+
+ if (err) {
+ vunmap((void *)addr);
+ return NULL;
+ }
+
+ flush_cache_vmap(addr, addr + size);
+ return (void __iomem *) (offset + addr);
+}
+
+void __iomem *__arm_ioremap_caller(phys_addr_t phys_addr, size_t size,
+ unsigned int mtype, void *caller)
+{
+ phys_addr_t 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 __arm_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 *
+__arm_ioremap_pfn(unsigned long pfn, unsigned long offset, size_t size,
+ unsigned int mtype)
+{
+ return __arm_ioremap_pfn_caller(pfn, offset, size, mtype,
+ __builtin_return_address(0));
+}
+EXPORT_SYMBOL(__arm_ioremap_pfn);
+
+void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t,
+ unsigned int, void *) =
+ __arm_ioremap_caller;
+
+void __iomem *ioremap(resource_size_t res_cookie, size_t size)
+{
+ return arch_ioremap_caller(res_cookie, size, MT_DEVICE,
+ __builtin_return_address(0));
+}
+EXPORT_SYMBOL(ioremap);
+
+void __iomem *ioremap_cache(resource_size_t res_cookie, size_t size)
+ __alias(ioremap_cached);
+
+void __iomem *ioremap_cached(resource_size_t res_cookie, size_t size)
+{
+ return arch_ioremap_caller(res_cookie, size, MT_DEVICE_CACHED,
+ __builtin_return_address(0));
+}
+EXPORT_SYMBOL(ioremap_cache);
+EXPORT_SYMBOL(ioremap_cached);
+
+void __iomem *ioremap_wc(resource_size_t res_cookie, size_t size)
+{
+ return arch_ioremap_caller(res_cookie, size, MT_DEVICE_WC,
+ __builtin_return_address(0));
+}
+EXPORT_SYMBOL(ioremap_wc);
+
+/*
+ * Remap an arbitrary physical address space into the kernel virtual
+ * address space as memory. Needed when the kernel wants to execute
+ * code in external memory. This is needed for reprogramming source
+ * clocks that would affect normal memory for example. Please see
+ * CONFIG_GENERIC_ALLOCATOR for allocating external memory.
+ */
+void __iomem *
+__arm_ioremap_exec(phys_addr_t phys_addr, size_t size, bool cached)
+{
+ unsigned int mtype;
+
+ if (cached)
+ mtype = MT_MEMORY_RWX;
+ else
+ mtype = MT_MEMORY_RWX_NONCACHED;
+
+ return __arm_ioremap_caller(phys_addr, size, mtype,
+ __builtin_return_address(0));
+}
+
+void *arch_memremap_wb(phys_addr_t phys_addr, size_t size)
+{
+ return (__force void *)arch_ioremap_caller(phys_addr, size,
+ MT_MEMORY_RW,
+ __builtin_return_address(0));
+}
+
+void __iounmap(volatile void __iomem *io_addr)
+{
+ void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
+ struct static_vm *svm;
+
+ /* If this is a static mapping, we must leave it alone */
+ svm = find_static_vm_vaddr(addr);
+ if (svm)
+ return;
+
+#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
+ {
+ struct vm_struct *vm;
+
+ vm = find_vm_area(addr);
+
+ /*
+ * 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.
+ */
+ if (vm && (vm->flags & VM_ARM_SECTION_MAPPING))
+ unmap_area_sections((unsigned long)vm->addr, vm->size);
+ }
+#endif
+
+ vunmap(addr);
+}
+
+void (*arch_iounmap)(volatile void __iomem *) = __iounmap;
+
+void iounmap(volatile void __iomem *cookie)
+{
+ arch_iounmap(cookie);
+}
+EXPORT_SYMBOL(iounmap);
+
+#ifdef CONFIG_PCI
+static int pci_ioremap_mem_type = MT_DEVICE;
+
+void pci_ioremap_set_mem_type(int mem_type)
+{
+ pci_ioremap_mem_type = mem_type;
+}
+
+int pci_ioremap_io(unsigned int offset, phys_addr_t phys_addr)
+{
+ BUG_ON(offset + SZ_64K - 1 > IO_SPACE_LIMIT);
+
+ return ioremap_page_range(PCI_IO_VIRT_BASE + offset,
+ PCI_IO_VIRT_BASE + offset + SZ_64K,
+ phys_addr,
+ __pgprot(get_mem_type(pci_ioremap_mem_type)->prot_pte));
+}
+EXPORT_SYMBOL_GPL(pci_ioremap_io);
+
+void __iomem *pci_remap_cfgspace(resource_size_t res_cookie, size_t size)
+{
+ return arch_ioremap_caller(res_cookie, size, MT_UNCACHED,
+ __builtin_return_address(0));
+}
+EXPORT_SYMBOL_GPL(pci_remap_cfgspace);
+#endif
+
+/*
+ * Must be called after early_fixmap_init
+ */
+void __init early_ioremap_init(void)
+{
+ early_ioremap_setup();
+}