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v6.8
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  PowerPC version
  4 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
  5 *
  6 *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
  7 *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
  8 *    Copyright (C) 1996 Paul Mackerras
  9 *  PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
 10 *
 11 *  Derived from "arch/i386/mm/init.c"
 12 *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
 13 */
 14
 
 
 
 
 
 
 
 
 
 
 15#include <linux/memblock.h>
 16#include <linux/highmem.h>
 
 
 17#include <linux/suspend.h>
 18#include <linux/dma-direct.h>
 19
 20#include <asm/swiotlb.h>
 
 
 
 
 
 
 
 
 
 21#include <asm/machdep.h>
 22#include <asm/rtas.h>
 23#include <asm/kasan.h>
 24#include <asm/svm.h>
 25#include <asm/mmzone.h>
 26#include <asm/ftrace.h>
 27#include <asm/code-patching.h>
 28#include <asm/setup.h>
 29#include <asm/fixmap.h>
 
 
 30
 31#include <mm/mmu_decl.h>
 32
 
 
 
 
 
 33unsigned long long memory_limit;
 
 
 
 
 
 
 
 34
 35unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
 36EXPORT_SYMBOL(empty_zero_page);
 
 
 
 
 37
 38pgprot_t __phys_mem_access_prot(unsigned long pfn, unsigned long size,
 39				pgprot_t vma_prot)
 40{
 41	if (ppc_md.phys_mem_access_prot)
 42		return ppc_md.phys_mem_access_prot(pfn, size, vma_prot);
 43
 44	if (!page_is_ram(pfn))
 45		vma_prot = pgprot_noncached(vma_prot);
 46
 47	return vma_prot;
 48}
 49EXPORT_SYMBOL(__phys_mem_access_prot);
 50
 51#ifdef CONFIG_MEMORY_HOTPLUG
 52static DEFINE_MUTEX(linear_mapping_mutex);
 53
 54#ifdef CONFIG_NUMA
 55int memory_add_physaddr_to_nid(u64 start)
 56{
 57	return hot_add_scn_to_nid(start);
 58}
 59EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
 60#endif
 61
 62int __weak create_section_mapping(unsigned long start, unsigned long end,
 63				  int nid, pgprot_t prot)
 64{
 65	return -ENODEV;
 66}
 67
 68int __weak remove_section_mapping(unsigned long start, unsigned long end)
 69{
 70	return -ENODEV;
 71}
 72
 73int __ref arch_create_linear_mapping(int nid, u64 start, u64 size,
 74				     struct mhp_params *params)
 75{
 
 
 76	int rc;
 77
 
 
 78	start = (unsigned long)__va(start);
 79	mutex_lock(&linear_mapping_mutex);
 80	rc = create_section_mapping(start, start + size, nid,
 81				    params->pgprot);
 82	mutex_unlock(&linear_mapping_mutex);
 83	if (rc) {
 84		pr_warn("Unable to create linear mapping for 0x%llx..0x%llx: %d\n",
 85			start, start + size, rc);
 86		return -EFAULT;
 87	}
 88	return 0;
 
 
 89}
 90
 91void __ref arch_remove_linear_mapping(u64 start, u64 size)
 
 92{
 
 
 
 93	int ret;
 94
 
 
 95	/* Remove htab bolted mappings for this section of memory */
 96	start = (unsigned long)__va(start);
 97
 98	mutex_lock(&linear_mapping_mutex);
 99	ret = remove_section_mapping(start, start + size);
100	mutex_unlock(&linear_mapping_mutex);
101	if (ret)
102		pr_warn("Unable to remove linear mapping for 0x%llx..0x%llx: %d\n",
103			start, start + size, ret);
104
105	/* Ensure all vmalloc mappings are flushed in case they also
106	 * hit that section of memory
107	 */
108	vm_unmap_aliases();
109}
110
111/*
112 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
113 * updating.
114 */
115static void update_end_of_memory_vars(u64 start, u64 size)
116{
117	unsigned long end_pfn = PFN_UP(start + size);
118
119	if (end_pfn > max_pfn) {
120		max_pfn = end_pfn;
121		max_low_pfn = end_pfn;
122		high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
123	}
124}
125
126int __ref add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
127		    struct mhp_params *params)
128{
129	int ret;
130
131	ret = __add_pages(nid, start_pfn, nr_pages, params);
132	if (ret)
133		return ret;
134
135	/* update max_pfn, max_low_pfn and high_memory */
136	update_end_of_memory_vars(start_pfn << PAGE_SHIFT,
137				  nr_pages << PAGE_SHIFT);
138
139	return ret;
140}
141
142int __ref arch_add_memory(int nid, u64 start, u64 size,
143			  struct mhp_params *params)
144{
145	unsigned long start_pfn = start >> PAGE_SHIFT;
146	unsigned long nr_pages = size >> PAGE_SHIFT;
147	int rc;
148
149	rc = arch_create_linear_mapping(nid, start, size, params);
150	if (rc)
151		return rc;
152	rc = add_pages(nid, start_pfn, nr_pages, params);
153	if (rc)
154		arch_remove_linear_mapping(start, size);
155	return rc;
156}
157
158void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
159{
160	unsigned long start_pfn = start >> PAGE_SHIFT;
161	unsigned long nr_pages = size >> PAGE_SHIFT;
162
163	__remove_pages(start_pfn, nr_pages, altmap);
164	arch_remove_linear_mapping(start, size);
165}
166#endif
167
168#ifndef CONFIG_NUMA
169void __init mem_topology_setup(void)
170{
171	max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
172	min_low_pfn = MEMORY_START >> PAGE_SHIFT;
173#ifdef CONFIG_HIGHMEM
174	max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
175#endif
176
177	/* Place all memblock_regions in the same node and merge contiguous
178	 * memblock_regions
179	 */
180	memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
181}
182
183void __init initmem_init(void)
184{
 
 
185	sparse_init();
186}
187
188/* mark pages that don't exist as nosave */
189static int __init mark_nonram_nosave(void)
190{
191	unsigned long spfn, epfn, prev = 0;
192	int i;
193
194	for_each_mem_pfn_range(i, MAX_NUMNODES, &spfn, &epfn, NULL) {
195		if (prev && prev < spfn)
196			register_nosave_region(prev, spfn);
197
198		prev = epfn;
 
 
 
 
 
199	}
200
201	return 0;
202}
203#else /* CONFIG_NUMA */
204static int __init mark_nonram_nosave(void)
205{
206	return 0;
207}
208#endif
209
210/*
211 * Zones usage:
212 *
213 * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be
214 * everything else. GFP_DMA32 page allocations automatically fall back to
215 * ZONE_DMA.
216 *
217 * By using 31-bit unconditionally, we can exploit zone_dma_bits to inform the
218 * generic DMA mapping code.  32-bit only devices (if not handled by an IOMMU
219 * anyway) will take a first dip into ZONE_NORMAL and get otherwise served by
220 * ZONE_DMA.
221 */
222static unsigned long max_zone_pfns[MAX_NR_ZONES];
223
224/*
225 * paging_init() sets up the page tables - in fact we've already done this.
226 */
227void __init paging_init(void)
228{
229	unsigned long long total_ram = memblock_phys_mem_size();
230	phys_addr_t top_of_ram = memblock_end_of_DRAM();
231
232#ifdef CONFIG_HIGHMEM
233	unsigned long v = __fix_to_virt(FIX_KMAP_END);
234	unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN);
235
236	for (; v < end; v += PAGE_SIZE)
237		map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */
 
238
 
239	map_kernel_page(PKMAP_BASE, 0, __pgprot(0));	/* XXX gross */
240	pkmap_page_table = virt_to_kpte(PKMAP_BASE);
 
 
 
241#endif /* CONFIG_HIGHMEM */
242
243	printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",
244	       (unsigned long long)top_of_ram, total_ram);
245	printk(KERN_DEBUG "Memory hole size: %ldMB\n",
246	       (long int)((top_of_ram - total_ram) >> 20));
247
248	/*
249	 * Allow 30-bit DMA for very limited Broadcom wifi chips on many
250	 * powerbooks.
251	 */
252	if (IS_ENABLED(CONFIG_PPC32))
253		zone_dma_bits = 30;
254	else
255		zone_dma_bits = 31;
256
257#ifdef CONFIG_ZONE_DMA
258	max_zone_pfns[ZONE_DMA]	= min(max_low_pfn,
259				      1UL << (zone_dma_bits - PAGE_SHIFT));
260#endif
261	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
262#ifdef CONFIG_HIGHMEM
263	max_zone_pfns[ZONE_HIGHMEM] = max_pfn;
264#endif
265
266	free_area_init(max_zone_pfns);
267
268	mark_nonram_nosave();
269}
270
271void __init mem_init(void)
272{
273	/*
274	 * book3s is limited to 16 page sizes due to encoding this in
275	 * a 4-bit field for slices.
276	 */
277	BUILD_BUG_ON(MMU_PAGE_COUNT > 16);
278
279#ifdef CONFIG_SWIOTLB
280	/*
281	 * Some platforms (e.g. 85xx) limit DMA-able memory way below
282	 * 4G. We force memblock to bottom-up mode to ensure that the
283	 * memory allocated in swiotlb_init() is DMA-able.
284	 * As it's the last memblock allocation, no need to reset it
285	 * back to to-down.
286	 */
287	memblock_set_bottom_up(true);
288	swiotlb_init(ppc_swiotlb_enable, ppc_swiotlb_flags);
289#endif
290
291	high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
292
293	kasan_late_init();
294
295	memblock_free_all();
296
297#ifdef CONFIG_HIGHMEM
298	{
299		unsigned long pfn, highmem_mapnr;
300
301		highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT;
302		for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
303			phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT;
304			struct page *page = pfn_to_page(pfn);
305			if (memblock_is_memory(paddr) && !memblock_is_reserved(paddr))
306				free_highmem_page(page);
307		}
308	}
309#endif /* CONFIG_HIGHMEM */
310
311#if defined(CONFIG_PPC_E500) && !defined(CONFIG_SMP)
312	/*
313	 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up
314	 * functions.... do it here for the non-smp case.
315	 */
316	per_cpu(next_tlbcam_idx, smp_processor_id()) =
317		(mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1;
318#endif
319
 
320#ifdef CONFIG_PPC32
321	pr_info("Kernel virtual memory layout:\n");
322#ifdef CONFIG_KASAN
323	pr_info("  * 0x%08lx..0x%08lx  : kasan shadow mem\n",
324		KASAN_SHADOW_START, KASAN_SHADOW_END);
325#endif
326	pr_info("  * 0x%08lx..0x%08lx  : fixmap\n", FIXADDR_START, FIXADDR_TOP);
327#ifdef CONFIG_HIGHMEM
328	pr_info("  * 0x%08lx..0x%08lx  : highmem PTEs\n",
329		PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
330#endif /* CONFIG_HIGHMEM */
331	if (ioremap_bot != IOREMAP_TOP)
332		pr_info("  * 0x%08lx..0x%08lx  : early ioremap\n",
333			ioremap_bot, IOREMAP_TOP);
334	pr_info("  * 0x%08lx..0x%08lx  : vmalloc & ioremap\n",
335		VMALLOC_START, VMALLOC_END);
336#ifdef MODULES_VADDR
337	pr_info("  * 0x%08lx..0x%08lx  : modules\n",
338		MODULES_VADDR, MODULES_END);
339#endif
340#endif /* CONFIG_PPC32 */
341}
342
343void free_initmem(void)
344{
345	ppc_md.progress = ppc_printk_progress;
346	mark_initmem_nx();
 
347	free_initmem_default(POISON_FREE_INITMEM);
348	ftrace_free_init_tramp();
349}
350
351/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
352 * System memory should not be in /proc/iomem but various tools expect it
353 * (eg kdump).
354 */
355static int __init add_system_ram_resources(void)
356{
357	phys_addr_t start, end;
358	u64 i;
359
360	for_each_mem_range(i, &start, &end) {
361		struct resource *res;
 
 
362
363		res = kzalloc(sizeof(struct resource), GFP_KERNEL);
364		WARN_ON(!res);
365
366		if (res) {
367			res->name = "System RAM";
368			res->start = start;
369			/*
370			 * In memblock, end points to the first byte after
371			 * the range while in resourses, end points to the
372			 * last byte in the range.
373			 */
374			res->end = end - 1;
375			res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
376			WARN_ON(request_resource(&iomem_resource, res) < 0);
377		}
378	}
379
380	return 0;
381}
382subsys_initcall(add_system_ram_resources);
383
384#ifdef CONFIG_STRICT_DEVMEM
385/*
386 * devmem_is_allowed(): check to see if /dev/mem access to a certain address
387 * is valid. The argument is a physical page number.
388 *
389 * Access has to be given to non-kernel-ram areas as well, these contain the
390 * PCI mmio resources as well as potential bios/acpi data regions.
391 */
392int devmem_is_allowed(unsigned long pfn)
393{
394	if (page_is_rtas_user_buf(pfn))
395		return 1;
396	if (iomem_is_exclusive(PFN_PHYS(pfn)))
397		return 0;
398	if (!page_is_ram(pfn))
399		return 1;
400	return 0;
401}
402#endif /* CONFIG_STRICT_DEVMEM */
403
404/*
405 * This is defined in kernel/resource.c but only powerpc needs to export it, for
406 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed.
407 */
408EXPORT_SYMBOL_GPL(walk_system_ram_range);
v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  PowerPC version
  4 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
  5 *
  6 *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
  7 *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
  8 *    Copyright (C) 1996 Paul Mackerras
  9 *  PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
 10 *
 11 *  Derived from "arch/i386/mm/init.c"
 12 *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
 13 */
 14
 15#include <linux/export.h>
 16#include <linux/sched.h>
 17#include <linux/kernel.h>
 18#include <linux/errno.h>
 19#include <linux/string.h>
 20#include <linux/gfp.h>
 21#include <linux/types.h>
 22#include <linux/mm.h>
 23#include <linux/stddef.h>
 24#include <linux/init.h>
 25#include <linux/memblock.h>
 26#include <linux/highmem.h>
 27#include <linux/initrd.h>
 28#include <linux/pagemap.h>
 29#include <linux/suspend.h>
 30#include <linux/hugetlb.h>
 31#include <linux/slab.h>
 32#include <linux/vmalloc.h>
 33#include <linux/memremap.h>
 34
 35#include <asm/pgalloc.h>
 36#include <asm/prom.h>
 37#include <asm/io.h>
 38#include <asm/mmu_context.h>
 39#include <asm/pgtable.h>
 40#include <asm/mmu.h>
 41#include <asm/smp.h>
 42#include <asm/machdep.h>
 43#include <asm/btext.h>
 44#include <asm/tlb.h>
 45#include <asm/sections.h>
 46#include <asm/sparsemem.h>
 47#include <asm/vdso.h>
 
 
 48#include <asm/fixmap.h>
 49#include <asm/swiotlb.h>
 50#include <asm/rtas.h>
 51
 52#include <mm/mmu_decl.h>
 53
 54#ifndef CPU_FTR_COHERENT_ICACHE
 55#define CPU_FTR_COHERENT_ICACHE	0	/* XXX for now */
 56#define CPU_FTR_NOEXECUTE	0
 57#endif
 58
 59unsigned long long memory_limit;
 60bool init_mem_is_free;
 61
 62#ifdef CONFIG_HIGHMEM
 63pte_t *kmap_pte;
 64EXPORT_SYMBOL(kmap_pte);
 65pgprot_t kmap_prot;
 66EXPORT_SYMBOL(kmap_prot);
 67
 68static inline pte_t *virt_to_kpte(unsigned long vaddr)
 69{
 70	return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr),
 71			vaddr), vaddr), vaddr);
 72}
 73#endif
 74
 75pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
 76			      unsigned long size, pgprot_t vma_prot)
 77{
 78	if (ppc_md.phys_mem_access_prot)
 79		return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot);
 80
 81	if (!page_is_ram(pfn))
 82		vma_prot = pgprot_noncached(vma_prot);
 83
 84	return vma_prot;
 85}
 86EXPORT_SYMBOL(phys_mem_access_prot);
 87
 88#ifdef CONFIG_MEMORY_HOTPLUG
 
 89
 90#ifdef CONFIG_NUMA
 91int memory_add_physaddr_to_nid(u64 start)
 92{
 93	return hot_add_scn_to_nid(start);
 94}
 
 95#endif
 96
 97int __weak create_section_mapping(unsigned long start, unsigned long end, int nid)
 
 98{
 99	return -ENODEV;
100}
101
102int __weak remove_section_mapping(unsigned long start, unsigned long end)
103{
104	return -ENODEV;
105}
106
107int __ref arch_add_memory(int nid, u64 start, u64 size,
108			struct mhp_restrictions *restrictions)
109{
110	unsigned long start_pfn = start >> PAGE_SHIFT;
111	unsigned long nr_pages = size >> PAGE_SHIFT;
112	int rc;
113
114	resize_hpt_for_hotplug(memblock_phys_mem_size());
115
116	start = (unsigned long)__va(start);
117	rc = create_section_mapping(start, start + size, nid);
 
 
 
118	if (rc) {
119		pr_warn("Unable to create mapping for hot added memory 0x%llx..0x%llx: %d\n",
120			start, start + size, rc);
121		return -EFAULT;
122	}
123	flush_dcache_range(start, start + size);
124
125	return __add_pages(nid, start_pfn, nr_pages, restrictions);
126}
127
128void __ref arch_remove_memory(int nid, u64 start, u64 size,
129			     struct vmem_altmap *altmap)
130{
131	unsigned long start_pfn = start >> PAGE_SHIFT;
132	unsigned long nr_pages = size >> PAGE_SHIFT;
133	struct page *page = pfn_to_page(start_pfn) + vmem_altmap_offset(altmap);
134	int ret;
135
136	__remove_pages(page_zone(page), start_pfn, nr_pages, altmap);
137
138	/* Remove htab bolted mappings for this section of memory */
139	start = (unsigned long)__va(start);
140	flush_dcache_range(start, start + size);
 
141	ret = remove_section_mapping(start, start + size);
142	WARN_ON_ONCE(ret);
 
 
 
143
144	/* Ensure all vmalloc mappings are flushed in case they also
145	 * hit that section of memory
146	 */
147	vm_unmap_aliases();
 
148
149	if (resize_hpt_for_hotplug(memblock_phys_mem_size()) == -ENOSPC)
150		pr_warn("Hash collision while resizing HPT\n");
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
151}
152#endif
153
154#ifndef CONFIG_NEED_MULTIPLE_NODES
155void __init mem_topology_setup(void)
156{
157	max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
158	min_low_pfn = MEMORY_START >> PAGE_SHIFT;
159#ifdef CONFIG_HIGHMEM
160	max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
161#endif
162
163	/* Place all memblock_regions in the same node and merge contiguous
164	 * memblock_regions
165	 */
166	memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
167}
168
169void __init initmem_init(void)
170{
171	/* XXX need to clip this if using highmem? */
172	sparse_memory_present_with_active_regions(0);
173	sparse_init();
174}
175
176/* mark pages that don't exist as nosave */
177static int __init mark_nonram_nosave(void)
178{
179	struct memblock_region *reg, *prev = NULL;
 
 
 
 
 
180
181	for_each_memblock(memory, reg) {
182		if (prev &&
183		    memblock_region_memory_end_pfn(prev) < memblock_region_memory_base_pfn(reg))
184			register_nosave_region(memblock_region_memory_end_pfn(prev),
185					       memblock_region_memory_base_pfn(reg));
186		prev = reg;
187	}
 
188	return 0;
189}
190#else /* CONFIG_NEED_MULTIPLE_NODES */
191static int __init mark_nonram_nosave(void)
192{
193	return 0;
194}
195#endif
196
197/*
198 * Zones usage:
199 *
200 * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be
201 * everything else. GFP_DMA32 page allocations automatically fall back to
202 * ZONE_DMA.
203 *
204 * By using 31-bit unconditionally, we can exploit ARCH_ZONE_DMA_BITS to
205 * inform the generic DMA mapping code.  32-bit only devices (if not handled
206 * by an IOMMU anyway) will take a first dip into ZONE_NORMAL and get
207 * otherwise served by ZONE_DMA.
208 */
209static unsigned long max_zone_pfns[MAX_NR_ZONES];
210
211/*
212 * paging_init() sets up the page tables - in fact we've already done this.
213 */
214void __init paging_init(void)
215{
216	unsigned long long total_ram = memblock_phys_mem_size();
217	phys_addr_t top_of_ram = memblock_end_of_DRAM();
218
219#ifdef CONFIG_PPC32
220	unsigned long v = __fix_to_virt(__end_of_fixed_addresses - 1);
221	unsigned long end = __fix_to_virt(FIX_HOLE);
222
223	for (; v < end; v += PAGE_SIZE)
224		map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */
225#endif
226
227#ifdef CONFIG_HIGHMEM
228	map_kernel_page(PKMAP_BASE, 0, __pgprot(0));	/* XXX gross */
229	pkmap_page_table = virt_to_kpte(PKMAP_BASE);
230
231	kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
232	kmap_prot = PAGE_KERNEL;
233#endif /* CONFIG_HIGHMEM */
234
235	printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",
236	       (unsigned long long)top_of_ram, total_ram);
237	printk(KERN_DEBUG "Memory hole size: %ldMB\n",
238	       (long int)((top_of_ram - total_ram) >> 20));
239
 
 
 
 
 
 
 
 
 
240#ifdef CONFIG_ZONE_DMA
241	max_zone_pfns[ZONE_DMA]	= min(max_low_pfn,
242				      1UL << (ARCH_ZONE_DMA_BITS - PAGE_SHIFT));
243#endif
244	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
245#ifdef CONFIG_HIGHMEM
246	max_zone_pfns[ZONE_HIGHMEM] = max_pfn;
247#endif
248
249	free_area_init_nodes(max_zone_pfns);
250
251	mark_nonram_nosave();
252}
253
254void __init mem_init(void)
255{
256	/*
257	 * book3s is limited to 16 page sizes due to encoding this in
258	 * a 4-bit field for slices.
259	 */
260	BUILD_BUG_ON(MMU_PAGE_COUNT > 16);
261
262#ifdef CONFIG_SWIOTLB
263	swiotlb_init(0);
 
 
 
 
 
 
 
 
264#endif
265
266	high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
267	set_max_mapnr(max_pfn);
 
 
268	memblock_free_all();
269
270#ifdef CONFIG_HIGHMEM
271	{
272		unsigned long pfn, highmem_mapnr;
273
274		highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT;
275		for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
276			phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT;
277			struct page *page = pfn_to_page(pfn);
278			if (!memblock_is_reserved(paddr))
279				free_highmem_page(page);
280		}
281	}
282#endif /* CONFIG_HIGHMEM */
283
284#if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP)
285	/*
286	 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up
287	 * functions.... do it here for the non-smp case.
288	 */
289	per_cpu(next_tlbcam_idx, smp_processor_id()) =
290		(mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1;
291#endif
292
293	mem_init_print_info(NULL);
294#ifdef CONFIG_PPC32
295	pr_info("Kernel virtual memory layout:\n");
296#ifdef CONFIG_KASAN
297	pr_info("  * 0x%08lx..0x%08lx  : kasan shadow mem\n",
298		KASAN_SHADOW_START, KASAN_SHADOW_END);
299#endif
300	pr_info("  * 0x%08lx..0x%08lx  : fixmap\n", FIXADDR_START, FIXADDR_TOP);
301#ifdef CONFIG_HIGHMEM
302	pr_info("  * 0x%08lx..0x%08lx  : highmem PTEs\n",
303		PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
304#endif /* CONFIG_HIGHMEM */
305	if (ioremap_bot != IOREMAP_TOP)
306		pr_info("  * 0x%08lx..0x%08lx  : early ioremap\n",
307			ioremap_bot, IOREMAP_TOP);
308	pr_info("  * 0x%08lx..0x%08lx  : vmalloc & ioremap\n",
309		VMALLOC_START, VMALLOC_END);
 
 
 
 
310#endif /* CONFIG_PPC32 */
311}
312
313void free_initmem(void)
314{
315	ppc_md.progress = ppc_printk_progress;
316	mark_initmem_nx();
317	init_mem_is_free = true;
318	free_initmem_default(POISON_FREE_INITMEM);
 
319}
320
321/*
322 * This is called when a page has been modified by the kernel.
323 * It just marks the page as not i-cache clean.  We do the i-cache
324 * flush later when the page is given to a user process, if necessary.
325 */
326void flush_dcache_page(struct page *page)
327{
328	if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
329		return;
330	/* avoid an atomic op if possible */
331	if (test_bit(PG_arch_1, &page->flags))
332		clear_bit(PG_arch_1, &page->flags);
333}
334EXPORT_SYMBOL(flush_dcache_page);
335
336void flush_dcache_icache_page(struct page *page)
337{
338#ifdef CONFIG_HUGETLB_PAGE
339	if (PageCompound(page)) {
340		flush_dcache_icache_hugepage(page);
341		return;
342	}
343#endif
344#if defined(CONFIG_PPC_8xx) || defined(CONFIG_PPC64)
345	/* On 8xx there is no need to kmap since highmem is not supported */
346	__flush_dcache_icache(page_address(page));
347#else
348	if (IS_ENABLED(CONFIG_BOOKE) || sizeof(phys_addr_t) > sizeof(void *)) {
349		void *start = kmap_atomic(page);
350		__flush_dcache_icache(start);
351		kunmap_atomic(start);
352	} else {
353		__flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT);
354	}
355#endif
356}
357EXPORT_SYMBOL(flush_dcache_icache_page);
358
359void clear_user_page(void *page, unsigned long vaddr, struct page *pg)
360{
361	clear_page(page);
362
363	/*
364	 * We shouldn't have to do this, but some versions of glibc
365	 * require it (ld.so assumes zero filled pages are icache clean)
366	 * - Anton
367	 */
368	flush_dcache_page(pg);
369}
370EXPORT_SYMBOL(clear_user_page);
371
372void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
373		    struct page *pg)
374{
375	copy_page(vto, vfrom);
376
377	/*
378	 * We should be able to use the following optimisation, however
379	 * there are two problems.
380	 * Firstly a bug in some versions of binutils meant PLT sections
381	 * were not marked executable.
382	 * Secondly the first word in the GOT section is blrl, used
383	 * to establish the GOT address. Until recently the GOT was
384	 * not marked executable.
385	 * - Anton
386	 */
387#if 0
388	if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0))
389		return;
390#endif
391
392	flush_dcache_page(pg);
393}
394
395void flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
396			     unsigned long addr, int len)
397{
398	unsigned long maddr;
399
400	maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK);
401	flush_icache_range(maddr, maddr + len);
402	kunmap(page);
403}
404EXPORT_SYMBOL(flush_icache_user_range);
405
406/*
407 * System memory should not be in /proc/iomem but various tools expect it
408 * (eg kdump).
409 */
410static int __init add_system_ram_resources(void)
411{
412	struct memblock_region *reg;
 
413
414	for_each_memblock(memory, reg) {
415		struct resource *res;
416		unsigned long base = reg->base;
417		unsigned long size = reg->size;
418
419		res = kzalloc(sizeof(struct resource), GFP_KERNEL);
420		WARN_ON(!res);
421
422		if (res) {
423			res->name = "System RAM";
424			res->start = base;
425			res->end = base + size - 1;
 
 
 
 
 
426			res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
427			WARN_ON(request_resource(&iomem_resource, res) < 0);
428		}
429	}
430
431	return 0;
432}
433subsys_initcall(add_system_ram_resources);
434
435#ifdef CONFIG_STRICT_DEVMEM
436/*
437 * devmem_is_allowed(): check to see if /dev/mem access to a certain address
438 * is valid. The argument is a physical page number.
439 *
440 * Access has to be given to non-kernel-ram areas as well, these contain the
441 * PCI mmio resources as well as potential bios/acpi data regions.
442 */
443int devmem_is_allowed(unsigned long pfn)
444{
445	if (page_is_rtas_user_buf(pfn))
446		return 1;
447	if (iomem_is_exclusive(PFN_PHYS(pfn)))
448		return 0;
449	if (!page_is_ram(pfn))
450		return 1;
451	return 0;
452}
453#endif /* CONFIG_STRICT_DEVMEM */
454
455/*
456 * This is defined in kernel/resource.c but only powerpc needs to export it, for
457 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed.
458 */
459EXPORT_SYMBOL_GPL(walk_system_ram_range);