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
30 #include <mm/mmu_decl.h>
31
32 unsigned long long memory_limit;
33
34 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
35 EXPORT_SYMBOL(empty_zero_page);
36
phys_mem_access_prot(struct file * file,unsigned long pfn,unsigned long size,pgprot_t vma_prot)37 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
38 unsigned long size, pgprot_t vma_prot)
39 {
40 if (ppc_md.phys_mem_access_prot)
41 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot);
42
43 if (!page_is_ram(pfn))
44 vma_prot = pgprot_noncached(vma_prot);
45
46 return vma_prot;
47 }
48 EXPORT_SYMBOL(phys_mem_access_prot);
49
50 #ifdef CONFIG_MEMORY_HOTPLUG
51 static DEFINE_MUTEX(linear_mapping_mutex);
52
53 #ifdef CONFIG_NUMA
memory_add_physaddr_to_nid(u64 start)54 int memory_add_physaddr_to_nid(u64 start)
55 {
56 return hot_add_scn_to_nid(start);
57 }
58 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
59 #endif
60
create_section_mapping(unsigned long start,unsigned long end,int nid,pgprot_t prot)61 int __weak create_section_mapping(unsigned long start, unsigned long end,
62 int nid, pgprot_t prot)
63 {
64 return -ENODEV;
65 }
66
remove_section_mapping(unsigned long start,unsigned long end)67 int __weak remove_section_mapping(unsigned long start, unsigned long end)
68 {
69 return -ENODEV;
70 }
71
arch_create_linear_mapping(int nid,u64 start,u64 size,struct mhp_params * params)72 int __ref arch_create_linear_mapping(int nid, u64 start, u64 size,
73 struct mhp_params *params)
74 {
75 int rc;
76
77 start = (unsigned long)__va(start);
78 mutex_lock(&linear_mapping_mutex);
79 rc = create_section_mapping(start, start + size, nid,
80 params->pgprot);
81 mutex_unlock(&linear_mapping_mutex);
82 if (rc) {
83 pr_warn("Unable to create linear mapping for 0x%llx..0x%llx: %d\n",
84 start, start + size, rc);
85 return -EFAULT;
86 }
87 return 0;
88 }
89
arch_remove_linear_mapping(u64 start,u64 size)90 void __ref arch_remove_linear_mapping(u64 start, u64 size)
91 {
92 int ret;
93
94 /* Remove htab bolted mappings for this section of memory */
95 start = (unsigned long)__va(start);
96
97 mutex_lock(&linear_mapping_mutex);
98 ret = remove_section_mapping(start, start + size);
99 mutex_unlock(&linear_mapping_mutex);
100 if (ret)
101 pr_warn("Unable to remove linear mapping for 0x%llx..0x%llx: %d\n",
102 start, start + size, ret);
103
104 /* Ensure all vmalloc mappings are flushed in case they also
105 * hit that section of memory
106 */
107 vm_unmap_aliases();
108 }
109
110 /*
111 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
112 * updating.
113 */
update_end_of_memory_vars(u64 start,u64 size)114 static void update_end_of_memory_vars(u64 start, u64 size)
115 {
116 unsigned long end_pfn = PFN_UP(start + size);
117
118 if (end_pfn > max_pfn) {
119 max_pfn = end_pfn;
120 max_low_pfn = end_pfn;
121 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
122 }
123 }
124
add_pages(int nid,unsigned long start_pfn,unsigned long nr_pages,struct mhp_params * params)125 int __ref add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
126 struct mhp_params *params)
127 {
128 int ret;
129
130 ret = __add_pages(nid, start_pfn, nr_pages, params);
131 if (ret)
132 return ret;
133
134 /* update max_pfn, max_low_pfn and high_memory */
135 update_end_of_memory_vars(start_pfn << PAGE_SHIFT,
136 nr_pages << PAGE_SHIFT);
137
138 return ret;
139 }
140
arch_add_memory(int nid,u64 start,u64 size,struct mhp_params * params)141 int __ref arch_add_memory(int nid, u64 start, u64 size,
142 struct mhp_params *params)
143 {
144 unsigned long start_pfn = start >> PAGE_SHIFT;
145 unsigned long nr_pages = size >> PAGE_SHIFT;
146 int rc;
147
148 rc = arch_create_linear_mapping(nid, start, size, params);
149 if (rc)
150 return rc;
151 rc = add_pages(nid, start_pfn, nr_pages, params);
152 if (rc)
153 arch_remove_linear_mapping(start, size);
154 return rc;
155 }
156
arch_remove_memory(u64 start,u64 size,struct vmem_altmap * altmap)157 void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
158 {
159 unsigned long start_pfn = start >> PAGE_SHIFT;
160 unsigned long nr_pages = size >> PAGE_SHIFT;
161
162 __remove_pages(start_pfn, nr_pages, altmap);
163 arch_remove_linear_mapping(start, size);
164 }
165 #endif
166
167 #ifndef CONFIG_NUMA
mem_topology_setup(void)168 void __init mem_topology_setup(void)
169 {
170 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
171 min_low_pfn = MEMORY_START >> PAGE_SHIFT;
172 #ifdef CONFIG_HIGHMEM
173 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
174 #endif
175
176 /* Place all memblock_regions in the same node and merge contiguous
177 * memblock_regions
178 */
179 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
180 }
181
initmem_init(void)182 void __init initmem_init(void)
183 {
184 sparse_init();
185 }
186
187 /* mark pages that don't exist as nosave */
mark_nonram_nosave(void)188 static int __init mark_nonram_nosave(void)
189 {
190 unsigned long spfn, epfn, prev = 0;
191 int i;
192
193 for_each_mem_pfn_range(i, MAX_NUMNODES, &spfn, &epfn, NULL) {
194 if (prev && prev < spfn)
195 register_nosave_region(prev, spfn);
196
197 prev = epfn;
198 }
199
200 return 0;
201 }
202 #else /* CONFIG_NUMA */
mark_nonram_nosave(void)203 static int __init mark_nonram_nosave(void)
204 {
205 return 0;
206 }
207 #endif
208
209 /*
210 * Zones usage:
211 *
212 * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be
213 * everything else. GFP_DMA32 page allocations automatically fall back to
214 * ZONE_DMA.
215 *
216 * By using 31-bit unconditionally, we can exploit zone_dma_bits to inform the
217 * generic DMA mapping code. 32-bit only devices (if not handled by an IOMMU
218 * anyway) will take a first dip into ZONE_NORMAL and get otherwise served by
219 * ZONE_DMA.
220 */
221 static unsigned long max_zone_pfns[MAX_NR_ZONES];
222
223 /*
224 * paging_init() sets up the page tables - in fact we've already done this.
225 */
paging_init(void)226 void __init paging_init(void)
227 {
228 unsigned long long total_ram = memblock_phys_mem_size();
229 phys_addr_t top_of_ram = memblock_end_of_DRAM();
230
231 #ifdef CONFIG_HIGHMEM
232 unsigned long v = __fix_to_virt(FIX_KMAP_END);
233 unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN);
234
235 for (; v < end; v += PAGE_SIZE)
236 map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */
237
238 map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */
239 pkmap_page_table = virt_to_kpte(PKMAP_BASE);
240 #endif /* CONFIG_HIGHMEM */
241
242 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",
243 (unsigned long long)top_of_ram, total_ram);
244 printk(KERN_DEBUG "Memory hole size: %ldMB\n",
245 (long int)((top_of_ram - total_ram) >> 20));
246
247 /*
248 * Allow 30-bit DMA for very limited Broadcom wifi chips on many
249 * powerbooks.
250 */
251 if (IS_ENABLED(CONFIG_PPC32))
252 zone_dma_bits = 30;
253 else
254 zone_dma_bits = 31;
255
256 #ifdef CONFIG_ZONE_DMA
257 max_zone_pfns[ZONE_DMA] = min(max_low_pfn,
258 1UL << (zone_dma_bits - PAGE_SHIFT));
259 #endif
260 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
261 #ifdef CONFIG_HIGHMEM
262 max_zone_pfns[ZONE_HIGHMEM] = max_pfn;
263 #endif
264
265 free_area_init(max_zone_pfns);
266
267 mark_nonram_nosave();
268 }
269
mem_init(void)270 void __init mem_init(void)
271 {
272 /*
273 * book3s is limited to 16 page sizes due to encoding this in
274 * a 4-bit field for slices.
275 */
276 BUILD_BUG_ON(MMU_PAGE_COUNT > 16);
277
278 #ifdef CONFIG_SWIOTLB
279 /*
280 * Some platforms (e.g. 85xx) limit DMA-able memory way below
281 * 4G. We force memblock to bottom-up mode to ensure that the
282 * memory allocated in swiotlb_init() is DMA-able.
283 * As it's the last memblock allocation, no need to reset it
284 * back to to-down.
285 */
286 memblock_set_bottom_up(true);
287 swiotlb_init(ppc_swiotlb_enable, ppc_swiotlb_flags);
288 #endif
289
290 kasan_late_init();
291
292 memblock_free_all();
293
294 #ifdef CONFIG_HIGHMEM
295 {
296 unsigned long pfn, highmem_mapnr;
297
298 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT;
299 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
300 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT;
301 struct page *page = pfn_to_page(pfn);
302 if (memblock_is_memory(paddr) && !memblock_is_reserved(paddr))
303 free_highmem_page(page);
304 }
305 }
306 #endif /* CONFIG_HIGHMEM */
307
308 #if defined(CONFIG_PPC_E500) && !defined(CONFIG_SMP)
309 /*
310 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up
311 * functions.... do it here for the non-smp case.
312 */
313 per_cpu(next_tlbcam_idx, smp_processor_id()) =
314 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1;
315 #endif
316
317 #ifdef CONFIG_PPC32
318 pr_info("Kernel virtual memory layout:\n");
319 #ifdef CONFIG_KASAN
320 pr_info(" * 0x%08lx..0x%08lx : kasan shadow mem\n",
321 KASAN_SHADOW_START, KASAN_SHADOW_END);
322 #endif
323 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP);
324 #ifdef CONFIG_HIGHMEM
325 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n",
326 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
327 #endif /* CONFIG_HIGHMEM */
328 if (ioremap_bot != IOREMAP_TOP)
329 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n",
330 ioremap_bot, IOREMAP_TOP);
331 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n",
332 VMALLOC_START, VMALLOC_END);
333 #ifdef MODULES_VADDR
334 pr_info(" * 0x%08lx..0x%08lx : modules\n",
335 MODULES_VADDR, MODULES_END);
336 #endif
337 #endif /* CONFIG_PPC32 */
338 }
339
free_initmem(void)340 void free_initmem(void)
341 {
342 ppc_md.progress = ppc_printk_progress;
343 mark_initmem_nx();
344 free_initmem_default(POISON_FREE_INITMEM);
345 ftrace_free_init_tramp();
346 }
347
348 /*
349 * System memory should not be in /proc/iomem but various tools expect it
350 * (eg kdump).
351 */
add_system_ram_resources(void)352 static int __init add_system_ram_resources(void)
353 {
354 phys_addr_t start, end;
355 u64 i;
356
357 for_each_mem_range(i, &start, &end) {
358 struct resource *res;
359
360 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
361 WARN_ON(!res);
362
363 if (res) {
364 res->name = "System RAM";
365 res->start = start;
366 /*
367 * In memblock, end points to the first byte after
368 * the range while in resourses, end points to the
369 * last byte in the range.
370 */
371 res->end = end - 1;
372 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
373 WARN_ON(request_resource(&iomem_resource, res) < 0);
374 }
375 }
376
377 return 0;
378 }
379 subsys_initcall(add_system_ram_resources);
380
381 #ifdef CONFIG_STRICT_DEVMEM
382 /*
383 * devmem_is_allowed(): check to see if /dev/mem access to a certain address
384 * is valid. The argument is a physical page number.
385 *
386 * Access has to be given to non-kernel-ram areas as well, these contain the
387 * PCI mmio resources as well as potential bios/acpi data regions.
388 */
devmem_is_allowed(unsigned long pfn)389 int devmem_is_allowed(unsigned long pfn)
390 {
391 if (page_is_rtas_user_buf(pfn))
392 return 1;
393 if (iomem_is_exclusive(PFN_PHYS(pfn)))
394 return 0;
395 if (!page_is_ram(pfn))
396 return 1;
397 return 0;
398 }
399 #endif /* CONFIG_STRICT_DEVMEM */
400
401 /*
402 * This is defined in kernel/resource.c but only powerpc needs to export it, for
403 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed.
404 */
405 EXPORT_SYMBOL_GPL(walk_system_ram_range);
406