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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#include <linux/kernel.h>
 12
 13#include <asm/cacheflush.h>
 14#include <asm/sections.h>
 15#include <asm/page.h>
 16#include <asm/setup.h>
 17#include <asm/traps.h>
 18#include <asm/mach/arch.h>
 19#include <asm/cputype.h>
 20#include <asm/mpu.h>
 21#include <asm/procinfo.h>
 22
 23#include "mm.h"
 24
 25#ifdef CONFIG_ARM_MPU
 26struct mpu_rgn_info mpu_rgn_info;
 27
 28/* Region number */
 29static void rgnr_write(u32 v)
 30{
 31	asm("mcr        p15, 0, %0, c6, c2, 0" : : "r" (v));
 32}
 33
 34/* Data-side / unified region attributes */
 35
 36/* Region access control register */
 37static void dracr_write(u32 v)
 38{
 39	asm("mcr        p15, 0, %0, c6, c1, 4" : : "r" (v));
 40}
 41
 42/* Region size register */
 43static void drsr_write(u32 v)
 44{
 45	asm("mcr        p15, 0, %0, c6, c1, 2" : : "r" (v));
 46}
 47
 48/* Region base address register */
 49static void drbar_write(u32 v)
 50{
 51	asm("mcr        p15, 0, %0, c6, c1, 0" : : "r" (v));
 52}
 53
 54static u32 drbar_read(void)
 55{
 56	u32 v;
 57	asm("mrc        p15, 0, %0, c6, c1, 0" : "=r" (v));
 58	return v;
 59}
 60/* Optional instruction-side region attributes */
 61
 62/* I-side Region access control register */
 63static void iracr_write(u32 v)
 64{
 65	asm("mcr        p15, 0, %0, c6, c1, 5" : : "r" (v));
 66}
 67
 68/* I-side Region size register */
 69static void irsr_write(u32 v)
 70{
 71	asm("mcr        p15, 0, %0, c6, c1, 3" : : "r" (v));
 72}
 73
 74/* I-side Region base address register */
 75static void irbar_write(u32 v)
 76{
 77	asm("mcr        p15, 0, %0, c6, c1, 1" : : "r" (v));
 78}
 79
 80static unsigned long irbar_read(void)
 81{
 82	unsigned long v;
 83	asm("mrc        p15, 0, %0, c6, c1, 1" : "=r" (v));
 84	return v;
 85}
 86
 87/* MPU initialisation functions */
 88void __init sanity_check_meminfo_mpu(void)
 89{
 
 
 90	phys_addr_t phys_offset = PHYS_OFFSET;
 91	phys_addr_t aligned_region_size, specified_mem_size, rounded_mem_size;
 92	struct memblock_region *reg;
 93	bool first = true;
 94	phys_addr_t mem_start;
 95	phys_addr_t mem_end;
 96
 97	for_each_memblock(memory, reg) {
 98		if (first) {
 99			/*
100			 * Initially only use memory continuous from
101			 * PHYS_OFFSET */
102			if (reg->base != phys_offset)
103				panic("First memory bank must be contiguous from PHYS_OFFSET");
104
105			mem_start = reg->base;
106			mem_end = reg->base + reg->size;
107			specified_mem_size = reg->size;
108			first = false;
109		} else {
110			/*
111			 * memblock auto merges contiguous blocks, remove
112			 * all blocks afterwards in one go (we can't remove
113			 * blocks separately while iterating)
114			 */
115			pr_notice("Ignoring RAM after %pa, memory at %pa ignored\n",
116				  &mem_end, &reg->base);
117			memblock_remove(reg->base, 0 - reg->base);
118			break;
119		}
120	}
 
 
 
121
122	/*
123	 * MPU has curious alignment requirements: Size must be power of 2, and
124	 * region start must be aligned to the region size
125	 */
126	if (phys_offset != 0)
127		pr_info("PHYS_OFFSET != 0 => MPU Region size constrained by alignment requirements\n");
128
129	/*
130	 * Maximum aligned region might overflow phys_addr_t if phys_offset is
131	 * 0. Hence we keep everything below 4G until we take the smaller of
132	 * the aligned_region_size and rounded_mem_size, one of which is
133	 * guaranteed to be smaller than the maximum physical address.
134	 */
135	aligned_region_size = (phys_offset - 1) ^ (phys_offset);
136	/* Find the max power-of-two sized region that fits inside our bank */
137	rounded_mem_size = (1 <<  __fls(specified_mem_size)) - 1;
138
139	/* The actual region size is the smaller of the two */
140	aligned_region_size = aligned_region_size < rounded_mem_size
141				? aligned_region_size + 1
142				: rounded_mem_size + 1;
143
144	if (aligned_region_size != specified_mem_size) {
145		pr_warn("Truncating memory from %pa to %pa (MPU region constraints)",
146				&specified_mem_size, &aligned_region_size);
147		memblock_remove(mem_start + aligned_region_size,
148				specified_mem_size - aligned_region_size);
149
150		mem_end = mem_start + aligned_region_size;
151	}
152
153	pr_debug("MPU Region from %pa size %pa (end %pa))\n",
154		&phys_offset, &aligned_region_size, &mem_end);
155
156}
157
158static int mpu_present(void)
159{
160	return ((read_cpuid_ext(CPUID_EXT_MMFR0) & MMFR0_PMSA) == MMFR0_PMSAv7);
161}
162
163static int mpu_max_regions(void)
164{
165	/*
166	 * We don't support a different number of I/D side regions so if we
167	 * have separate instruction and data memory maps then return
168	 * whichever side has a smaller number of supported regions.
169	 */
170	u32 dregions, iregions, mpuir;
171	mpuir = read_cpuid(CPUID_MPUIR);
172
173	dregions = iregions = (mpuir & MPUIR_DREGION_SZMASK) >> MPUIR_DREGION;
174
175	/* Check for separate d-side and i-side memory maps */
176	if (mpuir & MPUIR_nU)
177		iregions = (mpuir & MPUIR_IREGION_SZMASK) >> MPUIR_IREGION;
178
179	/* Use the smallest of the two maxima */
180	return min(dregions, iregions);
181}
182
183static int mpu_iside_independent(void)
184{
185	/* MPUIR.nU specifies whether there is *not* a unified memory map */
186	return read_cpuid(CPUID_MPUIR) & MPUIR_nU;
187}
188
189static int mpu_min_region_order(void)
190{
191	u32 drbar_result, irbar_result;
192	/* We've kept a region free for this probing */
193	rgnr_write(MPU_PROBE_REGION);
194	isb();
195	/*
196	 * As per ARM ARM, write 0xFFFFFFFC to DRBAR to find the minimum
197	 * region order
198	*/
199	drbar_write(0xFFFFFFFC);
200	drbar_result = irbar_result = drbar_read();
201	drbar_write(0x0);
202	/* If the MPU is non-unified, we use the larger of the two minima*/
203	if (mpu_iside_independent()) {
204		irbar_write(0xFFFFFFFC);
205		irbar_result = irbar_read();
206		irbar_write(0x0);
207	}
208	isb(); /* Ensure that MPU region operations have completed */
209	/* Return whichever result is larger */
210	return __ffs(max(drbar_result, irbar_result));
211}
212
213static int mpu_setup_region(unsigned int number, phys_addr_t start,
214			unsigned int size_order, unsigned int properties)
215{
216	u32 size_data;
217
218	/* We kept a region free for probing resolution of MPU regions*/
219	if (number > mpu_max_regions() || number == MPU_PROBE_REGION)
220		return -ENOENT;
221
222	if (size_order > 32)
223		return -ENOMEM;
224
225	if (size_order < mpu_min_region_order())
226		return -ENOMEM;
227
228	/* Writing N to bits 5:1 (RSR_SZ)  specifies region size 2^N+1 */
229	size_data = ((size_order - 1) << MPU_RSR_SZ) | 1 << MPU_RSR_EN;
230
231	dsb(); /* Ensure all previous data accesses occur with old mappings */
232	rgnr_write(number);
233	isb();
234	drbar_write(start);
235	dracr_write(properties);
236	isb(); /* Propagate properties before enabling region */
237	drsr_write(size_data);
238
239	/* Check for independent I-side registers */
240	if (mpu_iside_independent()) {
241		irbar_write(start);
242		iracr_write(properties);
243		isb();
244		irsr_write(size_data);
245	}
246	isb();
247
248	/* Store region info (we treat i/d side the same, so only store d) */
249	mpu_rgn_info.rgns[number].dracr = properties;
250	mpu_rgn_info.rgns[number].drbar = start;
251	mpu_rgn_info.rgns[number].drsr = size_data;
252	return 0;
253}
254
255/*
256* Set up default MPU regions, doing nothing if there is no MPU
257*/
258void __init mpu_setup(void)
259{
260	int region_err;
261	if (!mpu_present())
262		return;
263
264	region_err = mpu_setup_region(MPU_RAM_REGION, PHYS_OFFSET,
265					ilog2(memblock.memory.regions[0].size),
266					MPU_AP_PL1RW_PL0RW | MPU_RGN_NORMAL);
267	if (region_err) {
268		panic("MPU region initialization failure! %d", region_err);
269	} else {
270		pr_info("Using ARMv7 PMSA Compliant MPU. "
271			 "Region independence: %s, Max regions: %d\n",
272			mpu_iside_independent() ? "Yes" : "No",
273			mpu_max_regions());
274	}
275}
276#else
277static void sanity_check_meminfo_mpu(void) {}
278static void __init mpu_setup(void) {}
279#endif /* CONFIG_ARM_MPU */
280
281void __init arm_mm_memblock_reserve(void)
282{
283#ifndef CONFIG_CPU_V7M
284	/*
285	 * Register the exception vector page.
286	 * some architectures which the DRAM is the exception vector to trap,
287	 * alloc_page breaks with error, although it is not NULL, but "0."
288	 */
289	memblock_reserve(CONFIG_VECTORS_BASE, 2 * PAGE_SIZE);
290#else /* ifndef CONFIG_CPU_V7M */
291	/*
292	 * There is no dedicated vector page on V7-M. So nothing needs to be
293	 * reserved here.
294	 */
295#endif
296}
297
298void __init sanity_check_meminfo(void)
299{
300	phys_addr_t end;
301	sanity_check_meminfo_mpu();
302	end = memblock_end_of_DRAM();
303	high_memory = __va(end - 1) + 1;
304	memblock_set_current_limit(end);
 
 
 
 
 
 
 
 
305}
306
307/*
308 * paging_init() sets up the page tables, initialises the zone memory
309 * maps, and sets up the zero page, bad page and bad page tables.
310 */
311void __init paging_init(const struct machine_desc *mdesc)
312{
313	early_trap_init((void *)CONFIG_VECTORS_BASE);
314	mpu_setup();
315	bootmem_init();
316}
317
318/*
319 * We don't need to do anything here for nommu machines.
320 */
321void setup_mm_for_reboot(void)
322{
323}
324
325void flush_dcache_page(struct page *page)
326{
327	__cpuc_flush_dcache_area(page_address(page), PAGE_SIZE);
328}
329EXPORT_SYMBOL(flush_dcache_page);
330
331void flush_kernel_dcache_page(struct page *page)
332{
333	__cpuc_flush_dcache_area(page_address(page), PAGE_SIZE);
334}
335EXPORT_SYMBOL(flush_kernel_dcache_page);
336
337void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
338		       unsigned long uaddr, void *dst, const void *src,
339		       unsigned long len)
340{
341	memcpy(dst, src, len);
342	if (vma->vm_flags & VM_EXEC)
343		__cpuc_coherent_user_range(uaddr, uaddr + len);
344}
345
346void __iomem *__arm_ioremap_pfn(unsigned long pfn, unsigned long offset,
347				size_t size, unsigned int mtype)
348{
349	if (pfn >= (0x100000000ULL >> PAGE_SHIFT))
350		return NULL;
351	return (void __iomem *) (offset + (pfn << PAGE_SHIFT));
352}
353EXPORT_SYMBOL(__arm_ioremap_pfn);
354
355void __iomem *__arm_ioremap_caller(phys_addr_t phys_addr, size_t size,
356				   unsigned int mtype, void *caller)
357{
358	return (void __iomem *)phys_addr;
359}
360
361void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t, unsigned int, void *);
362
363void __iomem *ioremap(resource_size_t res_cookie, size_t size)
364{
365	return __arm_ioremap_caller(res_cookie, size, MT_DEVICE,
366				    __builtin_return_address(0));
367}
368EXPORT_SYMBOL(ioremap);
369
370void __iomem *ioremap_cache(resource_size_t res_cookie, size_t size)
371{
372	return __arm_ioremap_caller(res_cookie, size, MT_DEVICE_CACHED,
373				    __builtin_return_address(0));
374}
375EXPORT_SYMBOL(ioremap_cache);
376
377void __iomem *ioremap_wc(resource_size_t res_cookie, size_t size)
378{
379	return __arm_ioremap_caller(res_cookie, size, MT_DEVICE_WC,
380				    __builtin_return_address(0));
381}
382EXPORT_SYMBOL(ioremap_wc);
383
384void __iounmap(volatile void __iomem *addr)
 
385{
 
386}
387EXPORT_SYMBOL(__iounmap);
388
389void (*arch_iounmap)(volatile void __iomem *);
390
391void iounmap(volatile void __iomem *addr)
392{
393}
394EXPORT_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/sections.h>
 15#include <asm/page.h>
 16#include <asm/setup.h>
 17#include <asm/traps.h>
 18#include <asm/mach/arch.h>
 19#include <asm/cputype.h>
 20#include <asm/mpu.h>
 21#include <asm/procinfo.h>
 22
 23#include "mm.h"
 24
 25#ifdef CONFIG_ARM_MPU
 26struct mpu_rgn_info mpu_rgn_info;
 27
 28/* Region number */
 29static void rgnr_write(u32 v)
 30{
 31	asm("mcr        p15, 0, %0, c6, c2, 0" : : "r" (v));
 32}
 33
 34/* Data-side / unified region attributes */
 35
 36/* Region access control register */
 37static void dracr_write(u32 v)
 38{
 39	asm("mcr        p15, 0, %0, c6, c1, 4" : : "r" (v));
 40}
 41
 42/* Region size register */
 43static void drsr_write(u32 v)
 44{
 45	asm("mcr        p15, 0, %0, c6, c1, 2" : : "r" (v));
 46}
 47
 48/* Region base address register */
 49static void drbar_write(u32 v)
 50{
 51	asm("mcr        p15, 0, %0, c6, c1, 0" : : "r" (v));
 52}
 53
 54static u32 drbar_read(void)
 55{
 56	u32 v;
 57	asm("mrc        p15, 0, %0, c6, c1, 0" : "=r" (v));
 58	return v;
 59}
 60/* Optional instruction-side region attributes */
 61
 62/* I-side Region access control register */
 63static void iracr_write(u32 v)
 64{
 65	asm("mcr        p15, 0, %0, c6, c1, 5" : : "r" (v));
 66}
 67
 68/* I-side Region size register */
 69static void irsr_write(u32 v)
 70{
 71	asm("mcr        p15, 0, %0, c6, c1, 3" : : "r" (v));
 72}
 73
 74/* I-side Region base address register */
 75static void irbar_write(u32 v)
 76{
 77	asm("mcr        p15, 0, %0, c6, c1, 1" : : "r" (v));
 78}
 79
 80static unsigned long irbar_read(void)
 81{
 82	unsigned long v;
 83	asm("mrc        p15, 0, %0, c6, c1, 1" : "=r" (v));
 84	return v;
 85}
 86
 87/* MPU initialisation functions */
 88void __init sanity_check_meminfo_mpu(void)
 89{
 90	int i;
 91	struct membank *bank = meminfo.bank;
 92	phys_addr_t phys_offset = PHYS_OFFSET;
 93	phys_addr_t aligned_region_size, specified_mem_size, rounded_mem_size;
 94
 95	/* Initially only use memory continuous from PHYS_OFFSET */
 96	if (bank_phys_start(&bank[0]) != phys_offset)
 97		panic("First memory bank must be contiguous from PHYS_OFFSET");
 98
 99	/* Banks have already been sorted by start address */
100	for (i = 1; i < meminfo.nr_banks; i++) {
101		if (bank[i].start <= bank_phys_end(&bank[0]) &&
102		    bank_phys_end(&bank[i]) > bank_phys_end(&bank[0])) {
103			bank[0].size = bank_phys_end(&bank[i]) - bank[0].start;
 
 
 
 
 
 
 
104		} else {
105			pr_notice("Ignoring RAM after 0x%.8lx. "
106			"First non-contiguous (ignored) bank start: 0x%.8lx\n",
107				(unsigned long)bank_phys_end(&bank[0]),
108				(unsigned long)bank_phys_start(&bank[i]));
 
 
 
 
109			break;
110		}
111	}
112	/* All contiguous banks are now merged in to the first bank */
113	meminfo.nr_banks = 1;
114	specified_mem_size = bank[0].size;
115
116	/*
117	 * MPU has curious alignment requirements: Size must be power of 2, and
118	 * region start must be aligned to the region size
119	 */
120	if (phys_offset != 0)
121		pr_info("PHYS_OFFSET != 0 => MPU Region size constrained by alignment requirements\n");
122
123	/*
124	 * Maximum aligned region might overflow phys_addr_t if phys_offset is
125	 * 0. Hence we keep everything below 4G until we take the smaller of
126	 * the aligned_region_size and rounded_mem_size, one of which is
127	 * guaranteed to be smaller than the maximum physical address.
128	 */
129	aligned_region_size = (phys_offset - 1) ^ (phys_offset);
130	/* Find the max power-of-two sized region that fits inside our bank */
131	rounded_mem_size = (1 <<  __fls(bank[0].size)) - 1;
132
133	/* The actual region size is the smaller of the two */
134	aligned_region_size = aligned_region_size < rounded_mem_size
135				? aligned_region_size + 1
136				: rounded_mem_size + 1;
137
138	if (aligned_region_size != specified_mem_size)
139		pr_warn("Truncating memory from 0x%.8lx to 0x%.8lx (MPU region constraints)",
140				(unsigned long)specified_mem_size,
141				(unsigned long)aligned_region_size);
142
143	meminfo.bank[0].size = aligned_region_size;
144	pr_debug("MPU Region from 0x%.8lx size 0x%.8lx (end 0x%.8lx))\n",
145		(unsigned long)phys_offset,
146		(unsigned long)aligned_region_size,
147		(unsigned long)bank_phys_end(&bank[0]));
 
148
149}
150
151static int mpu_present(void)
152{
153	return ((read_cpuid_ext(CPUID_EXT_MMFR0) & MMFR0_PMSA) == MMFR0_PMSAv7);
154}
155
156static int mpu_max_regions(void)
157{
158	/*
159	 * We don't support a different number of I/D side regions so if we
160	 * have separate instruction and data memory maps then return
161	 * whichever side has a smaller number of supported regions.
162	 */
163	u32 dregions, iregions, mpuir;
164	mpuir = read_cpuid(CPUID_MPUIR);
165
166	dregions = iregions = (mpuir & MPUIR_DREGION_SZMASK) >> MPUIR_DREGION;
167
168	/* Check for separate d-side and i-side memory maps */
169	if (mpuir & MPUIR_nU)
170		iregions = (mpuir & MPUIR_IREGION_SZMASK) >> MPUIR_IREGION;
171
172	/* Use the smallest of the two maxima */
173	return min(dregions, iregions);
174}
175
176static int mpu_iside_independent(void)
177{
178	/* MPUIR.nU specifies whether there is *not* a unified memory map */
179	return read_cpuid(CPUID_MPUIR) & MPUIR_nU;
180}
181
182static int mpu_min_region_order(void)
183{
184	u32 drbar_result, irbar_result;
185	/* We've kept a region free for this probing */
186	rgnr_write(MPU_PROBE_REGION);
187	isb();
188	/*
189	 * As per ARM ARM, write 0xFFFFFFFC to DRBAR to find the minimum
190	 * region order
191	*/
192	drbar_write(0xFFFFFFFC);
193	drbar_result = irbar_result = drbar_read();
194	drbar_write(0x0);
195	/* If the MPU is non-unified, we use the larger of the two minima*/
196	if (mpu_iside_independent()) {
197		irbar_write(0xFFFFFFFC);
198		irbar_result = irbar_read();
199		irbar_write(0x0);
200	}
201	isb(); /* Ensure that MPU region operations have completed */
202	/* Return whichever result is larger */
203	return __ffs(max(drbar_result, irbar_result));
204}
205
206static int mpu_setup_region(unsigned int number, phys_addr_t start,
207			unsigned int size_order, unsigned int properties)
208{
209	u32 size_data;
210
211	/* We kept a region free for probing resolution of MPU regions*/
212	if (number > mpu_max_regions() || number == MPU_PROBE_REGION)
213		return -ENOENT;
214
215	if (size_order > 32)
216		return -ENOMEM;
217
218	if (size_order < mpu_min_region_order())
219		return -ENOMEM;
220
221	/* Writing N to bits 5:1 (RSR_SZ)  specifies region size 2^N+1 */
222	size_data = ((size_order - 1) << MPU_RSR_SZ) | 1 << MPU_RSR_EN;
223
224	dsb(); /* Ensure all previous data accesses occur with old mappings */
225	rgnr_write(number);
226	isb();
227	drbar_write(start);
228	dracr_write(properties);
229	isb(); /* Propagate properties before enabling region */
230	drsr_write(size_data);
231
232	/* Check for independent I-side registers */
233	if (mpu_iside_independent()) {
234		irbar_write(start);
235		iracr_write(properties);
236		isb();
237		irsr_write(size_data);
238	}
239	isb();
240
241	/* Store region info (we treat i/d side the same, so only store d) */
242	mpu_rgn_info.rgns[number].dracr = properties;
243	mpu_rgn_info.rgns[number].drbar = start;
244	mpu_rgn_info.rgns[number].drsr = size_data;
245	return 0;
246}
247
248/*
249* Set up default MPU regions, doing nothing if there is no MPU
250*/
251void __init mpu_setup(void)
252{
253	int region_err;
254	if (!mpu_present())
255		return;
256
257	region_err = mpu_setup_region(MPU_RAM_REGION, PHYS_OFFSET,
258					ilog2(meminfo.bank[0].size),
259					MPU_AP_PL1RW_PL0RW | MPU_RGN_NORMAL);
260	if (region_err) {
261		panic("MPU region initialization failure! %d", region_err);
262	} else {
263		pr_info("Using ARMv7 PMSA Compliant MPU. "
264			 "Region independence: %s, Max regions: %d\n",
265			mpu_iside_independent() ? "Yes" : "No",
266			mpu_max_regions());
267	}
268}
269#else
270static void sanity_check_meminfo_mpu(void) {}
271static void __init mpu_setup(void) {}
272#endif /* CONFIG_ARM_MPU */
273
274void __init arm_mm_memblock_reserve(void)
275{
276#ifndef CONFIG_CPU_V7M
277	/*
278	 * Register the exception vector page.
279	 * some architectures which the DRAM is the exception vector to trap,
280	 * alloc_page breaks with error, although it is not NULL, but "0."
281	 */
282	memblock_reserve(CONFIG_VECTORS_BASE, PAGE_SIZE);
283#else /* ifndef CONFIG_CPU_V7M */
284	/*
285	 * There is no dedicated vector page on V7-M. So nothing needs to be
286	 * reserved here.
287	 */
288#endif
289}
290
291void __init sanity_check_meminfo(void)
292{
293	phys_addr_t end;
294	sanity_check_meminfo_mpu();
295	end = bank_phys_end(&meminfo.bank[meminfo.nr_banks - 1]);
296	high_memory = __va(end - 1) + 1;
297}
298
299/*
300 * early_paging_init() recreates boot time page table setup, allowing machines
301 * to switch over to a high (>4G) address space on LPAE systems
302 */
303void __init early_paging_init(const struct machine_desc *mdesc,
304			      struct proc_info_list *procinfo)
305{
306}
307
308/*
309 * paging_init() sets up the page tables, initialises the zone memory
310 * maps, and sets up the zero page, bad page and bad page tables.
311 */
312void __init paging_init(const struct machine_desc *mdesc)
313{
314	early_trap_init((void *)CONFIG_VECTORS_BASE);
315	mpu_setup();
316	bootmem_init();
317}
318
319/*
320 * We don't need to do anything here for nommu machines.
321 */
322void setup_mm_for_reboot(void)
323{
324}
325
326void flush_dcache_page(struct page *page)
327{
328	__cpuc_flush_dcache_area(page_address(page), PAGE_SIZE);
329}
330EXPORT_SYMBOL(flush_dcache_page);
331
332void flush_kernel_dcache_page(struct page *page)
333{
334	__cpuc_flush_dcache_area(page_address(page), PAGE_SIZE);
335}
336EXPORT_SYMBOL(flush_kernel_dcache_page);
337
338void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
339		       unsigned long uaddr, void *dst, const void *src,
340		       unsigned long len)
341{
342	memcpy(dst, src, len);
343	if (vma->vm_flags & VM_EXEC)
344		__cpuc_coherent_user_range(uaddr, uaddr + len);
345}
346
347void __iomem *__arm_ioremap_pfn(unsigned long pfn, unsigned long offset,
348				size_t size, unsigned int mtype)
349{
350	if (pfn >= (0x100000000ULL >> PAGE_SHIFT))
351		return NULL;
352	return (void __iomem *) (offset + (pfn << PAGE_SHIFT));
353}
354EXPORT_SYMBOL(__arm_ioremap_pfn);
355
356void __iomem *__arm_ioremap_pfn_caller(unsigned long pfn, unsigned long offset,
357			   size_t size, unsigned int mtype, void *caller)
358{
359	return __arm_ioremap_pfn(pfn, offset, size, mtype);
360}
361
362void __iomem *__arm_ioremap(phys_addr_t phys_addr, size_t size,
363			    unsigned int mtype)
 
 
 
 
 
 
 
 
364{
365	return (void __iomem *)phys_addr;
 
366}
367EXPORT_SYMBOL(__arm_ioremap);
368
369void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t, unsigned int, void *);
 
 
 
 
 
370
371void __iomem *__arm_ioremap_caller(phys_addr_t phys_addr, size_t size,
372				   unsigned int mtype, void *caller)
373{
374	return __arm_ioremap(phys_addr, size, mtype);
375}
 
376
377void (*arch_iounmap)(volatile void __iomem *);
378
379void __arm_iounmap(volatile void __iomem *addr)
380{
381}
382EXPORT_SYMBOL(__arm_iounmap);