path: root/lib/ioremap.c (plain)
blob: e04366171cba5370078845a88f6c3f0e70a67fe2

1	/*
2	* Re-map IO memory to kernel address space so that we can access it.
3	* This is needed for high PCI addresses that aren't mapped in the
4	* 640k-1MB IO memory area on PC's
5	*
6	* (C) Copyright 1995 1996 Linus Torvalds
7	*/
8	#include <linux/vmalloc.h>
9	#include <linux/mm.h>
10	#include <linux/sched.h>
11	#include <linux/io.h>
12	#include <linux/export.h>
13	#include <asm/cacheflush.h>
14	#include <asm/pgtable.h>
15	#ifdef CONFIG_AMLOGIC_DEBUG_FTRACE_PSTORE
16	#include <linux/moduleparam.h>
17	#include <linux/amlogic/debug_ftrace_ramoops.h>
18	#endif
19
20	#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
21	static int __read_mostly ioremap_pud_capable;
22	static int __read_mostly ioremap_pmd_capable;
23	static int __read_mostly ioremap_huge_disabled;
24
25	static int __init set_nohugeiomap(char *str)
26	{
27	ioremap_huge_disabled = 1;
28	return 0;
29	}
30	early_param("nohugeiomap", set_nohugeiomap);
31
32	void __init ioremap_huge_init(void)
33	{
34	if (!ioremap_huge_disabled) {
35	if (arch_ioremap_pud_supported())
36	ioremap_pud_capable = 1;
37	if (arch_ioremap_pmd_supported())
38	ioremap_pmd_capable = 1;
39	}
40	}
41
42	static inline int ioremap_pud_enabled(void)
43	{
44	return ioremap_pud_capable;
45	}
46
47	static inline int ioremap_pmd_enabled(void)
48	{
49	return ioremap_pmd_capable;
50	}
51
52	#else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
53	static inline int ioremap_pud_enabled(void) { return 0; }
54	static inline int ioremap_pmd_enabled(void) { return 0; }
55	#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
56
57	static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
58	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
59	{
60	pte_t *pte;
61	u64 pfn;
62
63	pfn = phys_addr >> PAGE_SHIFT;
64	pte = pte_alloc_kernel(pmd, addr);
65	if (!pte)
66	return -ENOMEM;
67	do {
68	BUG_ON(!pte_none(*pte));
69	set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
70	pfn++;
71	} while (pte++, addr += PAGE_SIZE, addr != end);
72	return 0;
73	}
74
75	static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
76	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
77	{
78	pmd_t *pmd;
79	unsigned long next;
80
81	phys_addr -= addr;
82	pmd = pmd_alloc(&init_mm, pud, addr);
83	if (!pmd)
84	return -ENOMEM;
85	do {
86	next = pmd_addr_end(addr, end);
87
88	if (ioremap_pmd_enabled() &&
89	((next - addr) == PMD_SIZE) &&
90	IS_ALIGNED(phys_addr + addr, PMD_SIZE) &&
91	pmd_free_pte_page(pmd, addr)) {
92	if (pmd_set_huge(pmd, phys_addr + addr, prot))
93	continue;
94	}
95
96	if (ioremap_pte_range(pmd, addr, next, phys_addr + addr, prot))
97	return -ENOMEM;
98	} while (pmd++, addr = next, addr != end);
99	return 0;
100	}
101
102	static inline int ioremap_pud_range(pgd_t *pgd, unsigned long addr,
103	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
104	{
105	pud_t *pud;
106	unsigned long next;
107
108	phys_addr -= addr;
109	pud = pud_alloc(&init_mm, pgd, addr);
110	if (!pud)
111	return -ENOMEM;
112	do {
113	next = pud_addr_end(addr, end);
114
115	if (ioremap_pud_enabled() &&
116	((next - addr) == PUD_SIZE) &&
117	IS_ALIGNED(phys_addr + addr, PUD_SIZE) &&
118	pud_free_pmd_page(pud, addr)) {
119	if (pud_set_huge(pud, phys_addr + addr, prot))
120	continue;
121	}
122
123	if (ioremap_pmd_range(pud, addr, next, phys_addr + addr, prot))
124	return -ENOMEM;
125	} while (pud++, addr = next, addr != end);
126	return 0;
127	}
128
129	#ifdef CONFIG_AMLOGIC_DEBUG_FTRACE_PSTORE
130	bool is_normal_memory(pgprot_t p)
131	{
132	#if defined(CONFIG_ARM)
133	return ((pgprot_val(p) & L_PTE_MT_MASK) == L_PTE_MT_WRITEALLOC);
134	#elif defined(CONFIG_ARM64)
135	return (pgprot_val(p) & PTE_ATTRINDX_MASK) == PTE_ATTRINDX(MT_NORMAL);
136	#else
137	#error "Unuspported architecture"
138	#endif
139	}
140	#endif
141
142	int ioremap_page_range(unsigned long addr,
143	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
144	{
145	pgd_t *pgd;
146	unsigned long start;
147	unsigned long next;
148	int err;
149
150	BUG_ON(addr >= end);
151
152	start = addr;
153	phys_addr -= addr;
154	pgd = pgd_offset_k(addr);
155	do {
156	next = pgd_addr_end(addr, end);
157	err = ioremap_pud_range(pgd, addr, next, phys_addr+addr, prot);
158	if (err)
159	break;
160	} while (pgd++, addr = next, addr != end);
161
162	flush_cache_vmap(start, end);
163	#ifdef CONFIG_AMLOGIC_DEBUG_FTRACE_PSTORE
164	if (need_dump_iomap() && !is_normal_memory(prot))
165	pr_err("io__map <va:0x%08lx-0x%08lx> pa:0x%lx,port:0x%lx\n",
166	start, end, (unsigned long)phys_addr,
167	(unsigned long)pgprot_val(prot));
168	#endif
169	return err;
170	}
171	EXPORT_SYMBOL_GPL(ioremap_page_range);
172