1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
4*4882a593Smuzhiyun */
5*4882a593Smuzhiyun
6*4882a593Smuzhiyun #include <linux/vmalloc.h>
7*4882a593Smuzhiyun #include <linux/init.h>
8*4882a593Smuzhiyun #include <linux/module.h>
9*4882a593Smuzhiyun #include <linux/io.h>
10*4882a593Smuzhiyun #include <linux/mm.h>
11*4882a593Smuzhiyun #include <linux/slab.h>
12*4882a593Smuzhiyun #include <linux/cache.h>
13*4882a593Smuzhiyun
arc_uncached_addr_space(phys_addr_t paddr)14*4882a593Smuzhiyun static inline bool arc_uncached_addr_space(phys_addr_t paddr)
15*4882a593Smuzhiyun {
16*4882a593Smuzhiyun if (is_isa_arcompact()) {
17*4882a593Smuzhiyun if (paddr >= ARC_UNCACHED_ADDR_SPACE)
18*4882a593Smuzhiyun return true;
19*4882a593Smuzhiyun } else if (paddr >= perip_base && paddr <= perip_end) {
20*4882a593Smuzhiyun return true;
21*4882a593Smuzhiyun }
22*4882a593Smuzhiyun
23*4882a593Smuzhiyun return false;
24*4882a593Smuzhiyun }
25*4882a593Smuzhiyun
ioremap(phys_addr_t paddr,unsigned long size)26*4882a593Smuzhiyun void __iomem *ioremap(phys_addr_t paddr, unsigned long size)
27*4882a593Smuzhiyun {
28*4882a593Smuzhiyun phys_addr_t end;
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun /* Don't allow wraparound or zero size */
31*4882a593Smuzhiyun end = paddr + size - 1;
32*4882a593Smuzhiyun if (!size || (end < paddr))
33*4882a593Smuzhiyun return NULL;
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun /*
36*4882a593Smuzhiyun * If the region is h/w uncached, MMU mapping can be elided as optim
37*4882a593Smuzhiyun * The cast to u32 is fine as this region can only be inside 4GB
38*4882a593Smuzhiyun */
39*4882a593Smuzhiyun if (arc_uncached_addr_space(paddr))
40*4882a593Smuzhiyun return (void __iomem *)(u32)paddr;
41*4882a593Smuzhiyun
42*4882a593Smuzhiyun return ioremap_prot(paddr, size, PAGE_KERNEL_NO_CACHE);
43*4882a593Smuzhiyun }
44*4882a593Smuzhiyun EXPORT_SYMBOL(ioremap);
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun /*
47*4882a593Smuzhiyun * ioremap with access flags
48*4882a593Smuzhiyun * Cache semantics wise it is same as ioremap - "forced" uncached.
49*4882a593Smuzhiyun * However unlike vanilla ioremap which bypasses ARC MMU for addresses in
50*4882a593Smuzhiyun * ARC hardware uncached region, this one still goes thru the MMU as caller
51*4882a593Smuzhiyun * might need finer access control (R/W/X)
52*4882a593Smuzhiyun */
ioremap_prot(phys_addr_t paddr,unsigned long size,unsigned long flags)53*4882a593Smuzhiyun void __iomem *ioremap_prot(phys_addr_t paddr, unsigned long size,
54*4882a593Smuzhiyun unsigned long flags)
55*4882a593Smuzhiyun {
56*4882a593Smuzhiyun unsigned int off;
57*4882a593Smuzhiyun unsigned long vaddr;
58*4882a593Smuzhiyun struct vm_struct *area;
59*4882a593Smuzhiyun phys_addr_t end;
60*4882a593Smuzhiyun pgprot_t prot = __pgprot(flags);
61*4882a593Smuzhiyun
62*4882a593Smuzhiyun /* Don't allow wraparound, zero size */
63*4882a593Smuzhiyun end = paddr + size - 1;
64*4882a593Smuzhiyun if ((!size) || (end < paddr))
65*4882a593Smuzhiyun return NULL;
66*4882a593Smuzhiyun
67*4882a593Smuzhiyun /* An early platform driver might end up here */
68*4882a593Smuzhiyun if (!slab_is_available())
69*4882a593Smuzhiyun return NULL;
70*4882a593Smuzhiyun
71*4882a593Smuzhiyun /* force uncached */
72*4882a593Smuzhiyun prot = pgprot_noncached(prot);
73*4882a593Smuzhiyun
74*4882a593Smuzhiyun /* Mappings have to be page-aligned */
75*4882a593Smuzhiyun off = paddr & ~PAGE_MASK;
76*4882a593Smuzhiyun paddr &= PAGE_MASK_PHYS;
77*4882a593Smuzhiyun size = PAGE_ALIGN(end + 1) - paddr;
78*4882a593Smuzhiyun
79*4882a593Smuzhiyun /*
80*4882a593Smuzhiyun * Ok, go for it..
81*4882a593Smuzhiyun */
82*4882a593Smuzhiyun area = get_vm_area(size, VM_IOREMAP);
83*4882a593Smuzhiyun if (!area)
84*4882a593Smuzhiyun return NULL;
85*4882a593Smuzhiyun area->phys_addr = paddr;
86*4882a593Smuzhiyun vaddr = (unsigned long)area->addr;
87*4882a593Smuzhiyun if (ioremap_page_range(vaddr, vaddr + size, paddr, prot)) {
88*4882a593Smuzhiyun vunmap((void __force *)vaddr);
89*4882a593Smuzhiyun return NULL;
90*4882a593Smuzhiyun }
91*4882a593Smuzhiyun return (void __iomem *)(off + (char __iomem *)vaddr);
92*4882a593Smuzhiyun }
93*4882a593Smuzhiyun EXPORT_SYMBOL(ioremap_prot);
94*4882a593Smuzhiyun
95*4882a593Smuzhiyun
iounmap(const volatile void __iomem * addr)96*4882a593Smuzhiyun void iounmap(const volatile void __iomem *addr)
97*4882a593Smuzhiyun {
98*4882a593Smuzhiyun /* weird double cast to handle phys_addr_t > 32 bits */
99*4882a593Smuzhiyun if (arc_uncached_addr_space((phys_addr_t)(u32)addr))
100*4882a593Smuzhiyun return;
101*4882a593Smuzhiyun
102*4882a593Smuzhiyun vfree((void *)(PAGE_MASK & (unsigned long __force)addr));
103*4882a593Smuzhiyun }
104*4882a593Smuzhiyun EXPORT_SYMBOL(iounmap);
105