1 // SPDX-License-Identifier: GPL-2.0-or-later <<
2 /* 1 /*
3 * OpenRISC ioremap.c !! 2 * This file is subject to the terms and conditions of the GNU General Public
>> 3 * License. See the file "COPYING" in the main directory of this archive
>> 4 * for more details.
4 * 5 *
5 * Linux architectural port borrowing liberall !! 6 * (C) Copyright 1995 1996 Linus Torvalds
6 * others. All original copyrights apply as p !! 7 * (C) Copyright 2001, 2002 Ralf Baechle
7 * declaration. <<
8 * <<
9 * Modifications for the OpenRISC architecture <<
10 * Copyright (C) 2003 Matjaz Breskvar <phoenix <<
11 * Copyright (C) 2010-2011 Jonas Bonn <jonas@s <<
12 */ 8 */
13 !! 9 #include <linux/export.h>
>> 10 #include <asm/addrspace.h>
>> 11 #include <asm/byteorder.h>
>> 12 #include <linux/ioport.h>
>> 13 #include <linux/sched.h>
>> 14 #include <linux/slab.h>
14 #include <linux/vmalloc.h> 15 #include <linux/vmalloc.h>
>> 16 #include <linux/mm_types.h>
15 #include <linux/io.h> 17 #include <linux/io.h>
16 #include <linux/pgtable.h> !! 18 #include <asm/cacheflush.h>
17 #include <asm/pgalloc.h> <<
18 #include <asm/fixmap.h> <<
19 #include <asm/bug.h> <<
20 #include <linux/sched.h> <<
21 #include <asm/tlbflush.h> 19 #include <asm/tlbflush.h>
>> 20 #include <ioremap.h>
>> 21
>> 22 #define IS_LOW512(addr) (!((phys_addr_t)(addr) & (phys_addr_t) ~0x1fffffffULL))
>> 23 #define IS_KSEG1(addr) (((unsigned long)(addr) & ~0x1fffffffUL) == CKSEG1)
>> 24
>> 25 static int __ioremap_check_ram(unsigned long start_pfn, unsigned long nr_pages,
>> 26 void *arg)
>> 27 {
>> 28 unsigned long i;
>> 29
>> 30 for (i = 0; i < nr_pages; i++) {
>> 31 if (pfn_valid(start_pfn + i) &&
>> 32 !PageReserved(pfn_to_page(start_pfn + i)))
>> 33 return 1;
>> 34 }
22 35
23 extern int mem_init_done; !! 36 return 0;
>> 37 }
24 38
25 /* 39 /*
26 * OK, this one's a bit tricky... ioremap can !! 40 * ioremap_prot - map bus memory into CPU space
27 * initialized (early serial console does this !! 41 * @phys_addr: bus address of the memory
28 * for its mapping. No userspace pages will e !! 42 * @size: size of the resource to map
29 * is initialized so this applies only to kern !! 43 *
30 * this is called before memory is initialized !! 44 * ioremap_prot gives the caller control over cache coherency attributes (CCA)
31 * the memblock infrastructure. <<
32 */ 45 */
33 !! 46 void __iomem *ioremap_prot(phys_addr_t phys_addr, unsigned long size,
34 pte_t __ref *pte_alloc_one_kernel(struct mm_st !! 47 unsigned long prot_val)
35 { 48 {
36 pte_t *pte; !! 49 unsigned long flags = prot_val & _CACHE_MASK;
>> 50 unsigned long offset, pfn, last_pfn;
>> 51 struct vm_struct *area;
>> 52 phys_addr_t last_addr;
>> 53 unsigned long vaddr;
>> 54 void __iomem *cpu_addr;
>> 55
>> 56 cpu_addr = plat_ioremap(phys_addr, size, flags);
>> 57 if (cpu_addr)
>> 58 return cpu_addr;
>> 59
>> 60 phys_addr = fixup_bigphys_addr(phys_addr, size);
>> 61
>> 62 /* Don't allow wraparound or zero size */
>> 63 last_addr = phys_addr + size - 1;
>> 64 if (!size || last_addr < phys_addr)
>> 65 return NULL;
>> 66
>> 67 /*
>> 68 * Map uncached objects in the low 512mb of address space using KSEG1,
>> 69 * otherwise map using page tables.
>> 70 */
>> 71 if (IS_LOW512(phys_addr) && IS_LOW512(last_addr) &&
>> 72 flags == _CACHE_UNCACHED)
>> 73 return (void __iomem *) CKSEG1ADDR(phys_addr);
>> 74
>> 75 /* Early remaps should use the unmapped regions til' VM is available */
>> 76 if (WARN_ON_ONCE(!slab_is_available()))
>> 77 return NULL;
>> 78
>> 79 /*
>> 80 * Don't allow anybody to remap RAM that may be allocated by the page
>> 81 * allocator, since that could lead to races & data clobbering.
>> 82 */
>> 83 pfn = PFN_DOWN(phys_addr);
>> 84 last_pfn = PFN_DOWN(last_addr);
>> 85 if (walk_system_ram_range(pfn, last_pfn - pfn + 1, NULL,
>> 86 __ioremap_check_ram) == 1) {
>> 87 WARN_ONCE(1, "ioremap on RAM at %pa - %pa\n",
>> 88 &phys_addr, &last_addr);
>> 89 return NULL;
>> 90 }
37 91
38 if (likely(mem_init_done)) { !! 92 /*
39 pte = (pte_t *)get_zeroed_page !! 93 * Mappings have to be page-aligned
40 } else { !! 94 */
41 pte = memblock_alloc(PAGE_SIZE !! 95 offset = phys_addr & ~PAGE_MASK;
42 if (!pte) !! 96 phys_addr &= PAGE_MASK;
43 panic("%s: Failed to a !! 97 size = PAGE_ALIGN(last_addr + 1) - phys_addr;
44 __func__, PAGE_S !! 98
>> 99 /*
>> 100 * Ok, go for it..
>> 101 */
>> 102 area = get_vm_area(size, VM_IOREMAP);
>> 103 if (!area)
>> 104 return NULL;
>> 105 vaddr = (unsigned long)area->addr;
>> 106
>> 107 flags |= _PAGE_GLOBAL | _PAGE_PRESENT | __READABLE | __WRITEABLE;
>> 108 if (ioremap_page_range(vaddr, vaddr + size, phys_addr,
>> 109 __pgprot(flags))) {
>> 110 free_vm_area(area);
>> 111 return NULL;
45 } 112 }
46 113
47 return pte; !! 114 return (void __iomem *)(vaddr + offset);
>> 115 }
>> 116 EXPORT_SYMBOL(ioremap_prot);
>> 117
>> 118 void iounmap(const volatile void __iomem *addr)
>> 119 {
>> 120 if (!plat_iounmap(addr) && !IS_KSEG1(addr))
>> 121 vunmap((void *)((unsigned long)addr & PAGE_MASK));
48 } 122 }
>> 123 EXPORT_SYMBOL(iounmap);
49 124
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