1 // SPDX-License-Identifier: GPL-2.0-or-later
4  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
9  *  PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
18 #include <linux/dma-direct.h>
27 #include <asm/code-patching.h>
33 unsigned long long memory_limit;
35 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
38 pgprot_t __phys_mem_access_prot(unsigned long pfn, unsigned long size,  in __phys_mem_access_prot()
62 int __weak create_section_mapping(unsigned long start, unsigned long end,  in create_section_mapping()
65 	return -ENODEV;  in create_section_mapping()
68 int __weak remove_section_mapping(unsigned long start, unsigned long end)  in remove_section_mapping()
70 	return -ENODEV;  in remove_section_mapping()
78 	start = (unsigned long)__va(start);  in arch_create_linear_mapping()
81 				    params->pgprot);  in arch_create_linear_mapping()
86 		return -EFAULT;  in arch_create_linear_mapping()
96 	start = (unsigned long)__va(start);  in arch_remove_linear_mapping()
117 	unsigned long end_pfn = PFN_UP(start + size);  in update_end_of_memory_vars()
122 		high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;  in update_end_of_memory_vars()
126 int __ref add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,  in add_pages()
145 	unsigned long start_pfn = start >> PAGE_SHIFT;  in arch_add_memory()
146 	unsigned long nr_pages = size >> PAGE_SHIFT;  in arch_add_memory()
160 	unsigned long start_pfn = start >> PAGE_SHIFT;  in arch_remove_memory()
161 	unsigned long nr_pages = size >> PAGE_SHIFT;  in arch_remove_memory()
191 	unsigned long spfn, epfn, prev = 0;  in mark_nonram_nosave()
213  * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be
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
222 static unsigned long max_zone_pfns[MAX_NR_ZONES];
225  * paging_init() sets up the page tables - in fact we've already done this.
229 	unsigned long long total_ram = memblock_phys_mem_size();  in paging_init()
233 	unsigned long v = __fix_to_virt(FIX_KMAP_END);  in paging_init()
234 	unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN);  in paging_init()
243 	printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",  in paging_init()
244 	       (unsigned long long)top_of_ram, total_ram);  in paging_init()
246 	       (long int)((top_of_ram - total_ram) >> 20));  in paging_init()
249 	 * Allow 30-bit DMA for very limited Broadcom wifi chips on many  in paging_init()
259 				      1UL << (zone_dma_bits - PAGE_SHIFT));  in paging_init()
275 	 * a 4-bit field for slices.  in mem_init()
281 	 * Some platforms (e.g. 85xx) limit DMA-able memory way below  in mem_init()
282 	 * 4G. We force memblock to bottom-up mode to ensure that the  in mem_init()
283 	 * memory allocated in swiotlb_init() is DMA-able.  in mem_init()
285 	 * back to to-down.  in mem_init()
299 		unsigned long pfn, highmem_mapnr;  in mem_init()
314 	 * functions.... do it here for the non-smp case.  in mem_init()
317 		(mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1;  in mem_init()
367 			res->name = "System RAM";  in add_system_ram_resources()
368 			res->start = start;  in add_system_ram_resources()
374 			res->end = end - 1;  in add_system_ram_resources()
375 			res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;  in add_system_ram_resources()
389  * Access has to be given to non-kernel-ram areas as well, these contain the
392 int devmem_is_allowed(unsigned long pfn)  in devmem_is_allowed()