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1/*
2 * linux/arch/arm/mm/nommu.c
3 *
4 * ARM uCLinux supporting functions.
5 */
6#include <linux/module.h>
7#include <linux/mm.h>
8#include <linux/pagemap.h>
9#include <linux/io.h>
10#include <linux/memblock.h>
11
12#include <asm/cacheflush.h>
13#include <asm/sections.h>
14#include <asm/page.h>
15#include <asm/setup.h>
16#include <asm/mach/arch.h>
17
18#include "mm.h"
19
20void __init arm_mm_memblock_reserve(void)
21{
22 /*
23 * Register the exception vector page.
24 * some architectures which the DRAM is the exception vector to trap,
25 * alloc_page breaks with error, although it is not NULL, but "0."
26 */
27 memblock_reserve(CONFIG_VECTORS_BASE, PAGE_SIZE);
28}
29
30void __init sanity_check_meminfo(void)
31{
32}
33
34/*
35 * paging_init() sets up the page tables, initialises the zone memory
36 * maps, and sets up the zero page, bad page and bad page tables.
37 */
38void __init paging_init(struct machine_desc *mdesc)
39{
40 bootmem_init();
41}
42
43/*
44 * We don't need to do anything here for nommu machines.
45 */
46void setup_mm_for_reboot(char mode)
47{
48}
49
50void flush_dcache_page(struct page *page)
51{
52 __cpuc_flush_dcache_area(page_address(page), PAGE_SIZE);
53}
54EXPORT_SYMBOL(flush_dcache_page);
55
56void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
57 unsigned long uaddr, void *dst, const void *src,
58 unsigned long len)
59{
60 memcpy(dst, src, len);
61 if (vma->vm_flags & VM_EXEC)
62 __cpuc_coherent_user_range(uaddr, uaddr + len);
63}
64
65void __iomem *__arm_ioremap_pfn(unsigned long pfn, unsigned long offset,
66 size_t size, unsigned int mtype)
67{
68 if (pfn >= (0x100000000ULL >> PAGE_SHIFT))
69 return NULL;
70 return (void __iomem *) (offset + (pfn << PAGE_SHIFT));
71}
72EXPORT_SYMBOL(__arm_ioremap_pfn);
73
74void __iomem *__arm_ioremap_pfn_caller(unsigned long pfn, unsigned long offset,
75 size_t size, unsigned int mtype, void *caller)
76{
77 return __arm_ioremap_pfn(pfn, offset, size, mtype);
78}
79
80void __iomem *__arm_ioremap(unsigned long phys_addr, size_t size,
81 unsigned int mtype)
82{
83 return (void __iomem *)phys_addr;
84}
85EXPORT_SYMBOL(__arm_ioremap);
86
87void __iomem *__arm_ioremap_caller(unsigned long phys_addr, size_t size,
88 unsigned int mtype, void *caller)
89{
90 return __arm_ioremap(phys_addr, size, mtype);
91}
92
93void __iounmap(volatile void __iomem *addr)
94{
95}
96EXPORT_SYMBOL(__iounmap);
1/*
2 * linux/arch/arm/mm/nommu.c
3 *
4 * ARM uCLinux supporting functions.
5 */
6#include <linux/module.h>
7#include <linux/mm.h>
8#include <linux/pagemap.h>
9#include <linux/io.h>
10#include <linux/memblock.h>
11#include <linux/kernel.h>
12
13#include <asm/cacheflush.h>
14#include <asm/cp15.h>
15#include <asm/sections.h>
16#include <asm/page.h>
17#include <asm/setup.h>
18#include <asm/traps.h>
19#include <asm/mach/arch.h>
20#include <asm/cputype.h>
21#include <asm/mpu.h>
22#include <asm/procinfo.h>
23
24#include "mm.h"
25
26unsigned long vectors_base;
27
28#ifdef CONFIG_ARM_MPU
29struct mpu_rgn_info mpu_rgn_info;
30#endif
31
32#ifdef CONFIG_CPU_CP15
33#ifdef CONFIG_CPU_HIGH_VECTOR
34unsigned long setup_vectors_base(void)
35{
36 unsigned long reg = get_cr();
37
38 set_cr(reg | CR_V);
39 return 0xffff0000;
40}
41#else /* CONFIG_CPU_HIGH_VECTOR */
42/* Write exception base address to VBAR */
43static inline void set_vbar(unsigned long val)
44{
45 asm("mcr p15, 0, %0, c12, c0, 0" : : "r" (val) : "cc");
46}
47
48/*
49 * Security extensions, bits[7:4], permitted values,
50 * 0b0000 - not implemented, 0b0001/0b0010 - implemented
51 */
52static inline bool security_extensions_enabled(void)
53{
54 /* Check CPUID Identification Scheme before ID_PFR1 read */
55 if ((read_cpuid_id() & 0x000f0000) == 0x000f0000)
56 return !!cpuid_feature_extract(CPUID_EXT_PFR1, 4);
57 return 0;
58}
59
60unsigned long setup_vectors_base(void)
61{
62 unsigned long base = 0, reg = get_cr();
63
64 set_cr(reg & ~CR_V);
65 if (security_extensions_enabled()) {
66 if (IS_ENABLED(CONFIG_REMAP_VECTORS_TO_RAM))
67 base = CONFIG_DRAM_BASE;
68 set_vbar(base);
69 } else if (IS_ENABLED(CONFIG_REMAP_VECTORS_TO_RAM)) {
70 if (CONFIG_DRAM_BASE != 0)
71 pr_err("Security extensions not enabled, vectors cannot be remapped to RAM, vectors base will be 0x00000000\n");
72 }
73
74 return base;
75}
76#endif /* CONFIG_CPU_HIGH_VECTOR */
77#endif /* CONFIG_CPU_CP15 */
78
79void __init arm_mm_memblock_reserve(void)
80{
81#ifndef CONFIG_CPU_V7M
82 vectors_base = IS_ENABLED(CONFIG_CPU_CP15) ? setup_vectors_base() : 0;
83 /*
84 * Register the exception vector page.
85 * some architectures which the DRAM is the exception vector to trap,
86 * alloc_page breaks with error, although it is not NULL, but "0."
87 */
88 memblock_reserve(vectors_base, 2 * PAGE_SIZE);
89#else /* ifndef CONFIG_CPU_V7M */
90 /*
91 * There is no dedicated vector page on V7-M. So nothing needs to be
92 * reserved here.
93 */
94#endif
95 /*
96 * In any case, always ensure address 0 is never used as many things
97 * get very confused if 0 is returned as a legitimate address.
98 */
99 memblock_reserve(0, 1);
100}
101
102void __init adjust_lowmem_bounds(void)
103{
104 phys_addr_t end;
105 adjust_lowmem_bounds_mpu();
106 end = memblock_end_of_DRAM();
107 high_memory = __va(end - 1) + 1;
108 memblock_set_current_limit(end);
109}
110
111/*
112 * paging_init() sets up the page tables, initialises the zone memory
113 * maps, and sets up the zero page, bad page and bad page tables.
114 */
115void __init paging_init(const struct machine_desc *mdesc)
116{
117 early_trap_init((void *)vectors_base);
118 mpu_setup();
119 bootmem_init();
120}
121
122/*
123 * We don't need to do anything here for nommu machines.
124 */
125void setup_mm_for_reboot(void)
126{
127}
128
129void flush_dcache_page(struct page *page)
130{
131 __cpuc_flush_dcache_area(page_address(page), PAGE_SIZE);
132}
133EXPORT_SYMBOL(flush_dcache_page);
134
135void flush_kernel_dcache_page(struct page *page)
136{
137 __cpuc_flush_dcache_area(page_address(page), PAGE_SIZE);
138}
139EXPORT_SYMBOL(flush_kernel_dcache_page);
140
141void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
142 unsigned long uaddr, void *dst, const void *src,
143 unsigned long len)
144{
145 memcpy(dst, src, len);
146 if (vma->vm_flags & VM_EXEC)
147 __cpuc_coherent_user_range(uaddr, uaddr + len);
148}
149
150void __iomem *__arm_ioremap_pfn(unsigned long pfn, unsigned long offset,
151 size_t size, unsigned int mtype)
152{
153 if (pfn >= (0x100000000ULL >> PAGE_SHIFT))
154 return NULL;
155 return (void __iomem *) (offset + (pfn << PAGE_SHIFT));
156}
157EXPORT_SYMBOL(__arm_ioremap_pfn);
158
159void __iomem *__arm_ioremap_caller(phys_addr_t phys_addr, size_t size,
160 unsigned int mtype, void *caller)
161{
162 return (void __iomem *)phys_addr;
163}
164
165void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t, unsigned int, void *);
166
167void __iomem *ioremap(resource_size_t res_cookie, size_t size)
168{
169 return __arm_ioremap_caller(res_cookie, size, MT_DEVICE,
170 __builtin_return_address(0));
171}
172EXPORT_SYMBOL(ioremap);
173
174void __iomem *ioremap_cache(resource_size_t res_cookie, size_t size)
175 __alias(ioremap_cached);
176
177void __iomem *ioremap_cached(resource_size_t res_cookie, size_t size)
178{
179 return __arm_ioremap_caller(res_cookie, size, MT_DEVICE_CACHED,
180 __builtin_return_address(0));
181}
182EXPORT_SYMBOL(ioremap_cache);
183EXPORT_SYMBOL(ioremap_cached);
184
185void __iomem *ioremap_wc(resource_size_t res_cookie, size_t size)
186{
187 return __arm_ioremap_caller(res_cookie, size, MT_DEVICE_WC,
188 __builtin_return_address(0));
189}
190EXPORT_SYMBOL(ioremap_wc);
191
192#ifdef CONFIG_PCI
193
194#include <asm/mach/map.h>
195
196void __iomem *pci_remap_cfgspace(resource_size_t res_cookie, size_t size)
197{
198 return arch_ioremap_caller(res_cookie, size, MT_UNCACHED,
199 __builtin_return_address(0));
200}
201EXPORT_SYMBOL_GPL(pci_remap_cfgspace);
202#endif
203
204void *arch_memremap_wb(phys_addr_t phys_addr, size_t size)
205{
206 return (void *)phys_addr;
207}
208
209void __iounmap(volatile void __iomem *addr)
210{
211}
212EXPORT_SYMBOL(__iounmap);
213
214void (*arch_iounmap)(volatile void __iomem *);
215
216void iounmap(volatile void __iomem *addr)
217{
218}
219EXPORT_SYMBOL(iounmap);