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/machdep.h>
21 #include <asm/rtas.h>
22 #include <asm/kasan.h>
23 #include <asm/svm.h>
24 #include <asm/mmzone.h>
25
26 #include <mm/mmu_decl.h>
27
28 unsigned long long memory_limit;
29 bool init_mem_is_free;
30
31 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
32 EXPORT_SYMBOL(empty_zero_page);
33
phys_mem_access_prot(struct file * file,unsigned long pfn,unsigned long size,pgprot_t vma_prot)34 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
35 unsigned long size, pgprot_t vma_prot)
36 {
37 if (ppc_md.phys_mem_access_prot)
38 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot);
39
40 if (!page_is_ram(pfn))
41 vma_prot = pgprot_noncached(vma_prot);
42
43 return vma_prot;
44 }
45 EXPORT_SYMBOL(phys_mem_access_prot);
46
47 #ifdef CONFIG_MEMORY_HOTPLUG
48 static DEFINE_MUTEX(linear_mapping_mutex);
49
50 #ifdef CONFIG_NUMA
memory_add_physaddr_to_nid(u64 start)51 int memory_add_physaddr_to_nid(u64 start)
52 {
53 return hot_add_scn_to_nid(start);
54 }
55 #endif
56
create_section_mapping(unsigned long start,unsigned long end,int nid,pgprot_t prot)57 int __weak create_section_mapping(unsigned long start, unsigned long end,
58 int nid, pgprot_t prot)
59 {
60 return -ENODEV;
61 }
62
remove_section_mapping(unsigned long start,unsigned long end)63 int __weak remove_section_mapping(unsigned long start, unsigned long end)
64 {
65 return -ENODEV;
66 }
67
arch_create_linear_mapping(int nid,u64 start,u64 size,struct mhp_params * params)68 int __ref arch_create_linear_mapping(int nid, u64 start, u64 size,
69 struct mhp_params *params)
70 {
71 int rc;
72
73 start = (unsigned long)__va(start);
74 mutex_lock(&linear_mapping_mutex);
75 rc = create_section_mapping(start, start + size, nid,
76 params->pgprot);
77 mutex_unlock(&linear_mapping_mutex);
78 if (rc) {
79 pr_warn("Unable to create linear mapping for 0x%llx..0x%llx: %d\n",
80 start, start + size, rc);
81 return -EFAULT;
82 }
83 return 0;
84 }
85
arch_remove_linear_mapping(u64 start,u64 size)86 void __ref arch_remove_linear_mapping(u64 start, u64 size)
87 {
88 int ret;
89
90 /* Remove htab bolted mappings for this section of memory */
91 start = (unsigned long)__va(start);
92
93 mutex_lock(&linear_mapping_mutex);
94 ret = remove_section_mapping(start, start + size);
95 mutex_unlock(&linear_mapping_mutex);
96 if (ret)
97 pr_warn("Unable to remove linear mapping for 0x%llx..0x%llx: %d\n",
98 start, start + size, ret);
99
100 /* Ensure all vmalloc mappings are flushed in case they also
101 * hit that section of memory
102 */
103 vm_unmap_aliases();
104 }
105
arch_add_memory(int nid,u64 start,u64 size,struct mhp_params * params)106 int __ref arch_add_memory(int nid, u64 start, u64 size,
107 struct mhp_params *params)
108 {
109 unsigned long start_pfn = start >> PAGE_SHIFT;
110 unsigned long nr_pages = size >> PAGE_SHIFT;
111 int rc;
112
113 rc = arch_create_linear_mapping(nid, start, size, params);
114 if (rc)
115 return rc;
116 rc = __add_pages(nid, start_pfn, nr_pages, params);
117 if (rc)
118 arch_remove_linear_mapping(start, size);
119 return rc;
120 }
121
arch_remove_memory(u64 start,u64 size,struct vmem_altmap * altmap)122 void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
123 {
124 unsigned long start_pfn = start >> PAGE_SHIFT;
125 unsigned long nr_pages = size >> PAGE_SHIFT;
126
127 __remove_pages(start_pfn, nr_pages, altmap);
128 arch_remove_linear_mapping(start, size);
129 }
130 #endif
131
132 #ifndef CONFIG_NUMA
mem_topology_setup(void)133 void __init mem_topology_setup(void)
134 {
135 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
136 min_low_pfn = MEMORY_START >> PAGE_SHIFT;
137 #ifdef CONFIG_HIGHMEM
138 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
139 #endif
140
141 /* Place all memblock_regions in the same node and merge contiguous
142 * memblock_regions
143 */
144 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
145 }
146
initmem_init(void)147 void __init initmem_init(void)
148 {
149 sparse_init();
150 }
151
152 /* mark pages that don't exist as nosave */
mark_nonram_nosave(void)153 static int __init mark_nonram_nosave(void)
154 {
155 unsigned long spfn, epfn, prev = 0;
156 int i;
157
158 for_each_mem_pfn_range(i, MAX_NUMNODES, &spfn, &epfn, NULL) {
159 if (prev && prev < spfn)
160 register_nosave_region(prev, spfn);
161
162 prev = epfn;
163 }
164
165 return 0;
166 }
167 #else /* CONFIG_NUMA */
mark_nonram_nosave(void)168 static int __init mark_nonram_nosave(void)
169 {
170 return 0;
171 }
172 #endif
173
174 /*
175 * Zones usage:
176 *
177 * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be
178 * everything else. GFP_DMA32 page allocations automatically fall back to
179 * ZONE_DMA.
180 *
181 * By using 31-bit unconditionally, we can exploit zone_dma_bits to inform the
182 * generic DMA mapping code. 32-bit only devices (if not handled by an IOMMU
183 * anyway) will take a first dip into ZONE_NORMAL and get otherwise served by
184 * ZONE_DMA.
185 */
186 static unsigned long max_zone_pfns[MAX_NR_ZONES];
187
188 /*
189 * paging_init() sets up the page tables - in fact we've already done this.
190 */
paging_init(void)191 void __init paging_init(void)
192 {
193 unsigned long long total_ram = memblock_phys_mem_size();
194 phys_addr_t top_of_ram = memblock_end_of_DRAM();
195
196 #ifdef CONFIG_HIGHMEM
197 unsigned long v = __fix_to_virt(FIX_KMAP_END);
198 unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN);
199
200 for (; v < end; v += PAGE_SIZE)
201 map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */
202
203 map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */
204 pkmap_page_table = virt_to_kpte(PKMAP_BASE);
205 #endif /* CONFIG_HIGHMEM */
206
207 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",
208 (unsigned long long)top_of_ram, total_ram);
209 printk(KERN_DEBUG "Memory hole size: %ldMB\n",
210 (long int)((top_of_ram - total_ram) >> 20));
211
212 /*
213 * Allow 30-bit DMA for very limited Broadcom wifi chips on many
214 * powerbooks.
215 */
216 if (IS_ENABLED(CONFIG_PPC32))
217 zone_dma_bits = 30;
218 else
219 zone_dma_bits = 31;
220
221 #ifdef CONFIG_ZONE_DMA
222 max_zone_pfns[ZONE_DMA] = min(max_low_pfn,
223 1UL << (zone_dma_bits - PAGE_SHIFT));
224 #endif
225 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
226 #ifdef CONFIG_HIGHMEM
227 max_zone_pfns[ZONE_HIGHMEM] = max_pfn;
228 #endif
229
230 free_area_init(max_zone_pfns);
231
232 mark_nonram_nosave();
233 }
234
mem_init(void)235 void __init mem_init(void)
236 {
237 /*
238 * book3s is limited to 16 page sizes due to encoding this in
239 * a 4-bit field for slices.
240 */
241 BUILD_BUG_ON(MMU_PAGE_COUNT > 16);
242
243 #ifdef CONFIG_SWIOTLB
244 /*
245 * Some platforms (e.g. 85xx) limit DMA-able memory way below
246 * 4G. We force memblock to bottom-up mode to ensure that the
247 * memory allocated in swiotlb_init() is DMA-able.
248 * As it's the last memblock allocation, no need to reset it
249 * back to to-down.
250 */
251 memblock_set_bottom_up(true);
252 if (is_secure_guest())
253 svm_swiotlb_init();
254 else
255 swiotlb_init(0);
256 #endif
257
258 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
259 set_max_mapnr(max_low_pfn);
260
261 kasan_late_init();
262
263 memblock_free_all();
264
265 #ifdef CONFIG_HIGHMEM
266 {
267 unsigned long pfn, highmem_mapnr;
268
269 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT;
270 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
271 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT;
272 struct page *page = pfn_to_page(pfn);
273 if (!memblock_is_reserved(paddr))
274 free_highmem_page(page);
275 }
276 }
277 #endif /* CONFIG_HIGHMEM */
278
279 #if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP)
280 /*
281 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up
282 * functions.... do it here for the non-smp case.
283 */
284 per_cpu(next_tlbcam_idx, smp_processor_id()) =
285 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1;
286 #endif
287
288 #ifdef CONFIG_PPC32
289 pr_info("Kernel virtual memory layout:\n");
290 #ifdef CONFIG_KASAN
291 pr_info(" * 0x%08lx..0x%08lx : kasan shadow mem\n",
292 KASAN_SHADOW_START, KASAN_SHADOW_END);
293 #endif
294 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP);
295 #ifdef CONFIG_HIGHMEM
296 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n",
297 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
298 #endif /* CONFIG_HIGHMEM */
299 if (ioremap_bot != IOREMAP_TOP)
300 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n",
301 ioremap_bot, IOREMAP_TOP);
302 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n",
303 VMALLOC_START, VMALLOC_END);
304 #ifdef MODULES_VADDR
305 pr_info(" * 0x%08lx..0x%08lx : modules\n",
306 MODULES_VADDR, MODULES_END);
307 #endif
308 #endif /* CONFIG_PPC32 */
309 }
310
free_initmem(void)311 void free_initmem(void)
312 {
313 ppc_md.progress = ppc_printk_progress;
314 mark_initmem_nx();
315 init_mem_is_free = true;
316 free_initmem_default(POISON_FREE_INITMEM);
317 }
318
319 /*
320 * System memory should not be in /proc/iomem but various tools expect it
321 * (eg kdump).
322 */
add_system_ram_resources(void)323 static int __init add_system_ram_resources(void)
324 {
325 phys_addr_t start, end;
326 u64 i;
327
328 for_each_mem_range(i, &start, &end) {
329 struct resource *res;
330
331 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
332 WARN_ON(!res);
333
334 if (res) {
335 res->name = "System RAM";
336 res->start = start;
337 /*
338 * In memblock, end points to the first byte after
339 * the range while in resourses, end points to the
340 * last byte in the range.
341 */
342 res->end = end - 1;
343 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
344 WARN_ON(request_resource(&iomem_resource, res) < 0);
345 }
346 }
347
348 return 0;
349 }
350 subsys_initcall(add_system_ram_resources);
351
352 #ifdef CONFIG_STRICT_DEVMEM
353 /*
354 * devmem_is_allowed(): check to see if /dev/mem access to a certain address
355 * is valid. The argument is a physical page number.
356 *
357 * Access has to be given to non-kernel-ram areas as well, these contain the
358 * PCI mmio resources as well as potential bios/acpi data regions.
359 */
devmem_is_allowed(unsigned long pfn)360 int devmem_is_allowed(unsigned long pfn)
361 {
362 if (page_is_rtas_user_buf(pfn))
363 return 1;
364 if (iomem_is_exclusive(PFN_PHYS(pfn)))
365 return 0;
366 if (!page_is_ram(pfn))
367 return 1;
368 return 0;
369 }
370 #endif /* CONFIG_STRICT_DEVMEM */
371
372 /*
373 * This is defined in kernel/resource.c but only powerpc needs to export it, for
374 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed.
375 */
376 EXPORT_SYMBOL_GPL(walk_system_ram_range);
377