71 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			71 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
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| /*
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|  * highmem.h: virtual kernel memory mappings for high memory
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|  *
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|  * PowerPC version, stolen from the i386 version.
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|  *
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|  * Used in CONFIG_HIGHMEM systems for memory pages which
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|  * are not addressable by direct kernel virtual addresses.
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|  *
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|  * Copyright (C) 1999 Gerhard Wichert, Siemens AG
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|  *		      Gerhard.Wichert@pdb.siemens.de
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|  *
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|  *
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|  * Redesigned the x86 32-bit VM architecture to deal with
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|  * up to 16 Terrabyte physical memory. With current x86 CPUs
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|  * we now support up to 64 Gigabytes physical RAM.
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|  *
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|  * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
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|  */
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| 
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| #ifndef _ASM_HIGHMEM_H
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| #define _ASM_HIGHMEM_H
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| 
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| #ifdef __KERNEL__
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| 
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| #include <linux/interrupt.h>
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| #include <asm/cacheflush.h>
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| #include <asm/page.h>
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| #include <asm/fixmap.h>
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| 
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| extern pte_t *pkmap_page_table;
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| 
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| /*
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|  * Right now we initialize only a single pte table. It can be extended
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|  * easily, subsequent pte tables have to be allocated in one physical
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|  * chunk of RAM.
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|  */
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| /*
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|  * We use one full pte table with 4K pages. And with 16K/64K/256K pages pte
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|  * table covers enough memory (32MB/512MB/2GB resp.), so that both FIXMAP
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|  * and PKMAP can be placed in a single pte table. We use 512 pages for PKMAP
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|  * in case of 16K/64K/256K page sizes.
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|  */
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| #ifdef CONFIG_PPC_4K_PAGES
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| #define PKMAP_ORDER	PTE_SHIFT
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| #else
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| #define PKMAP_ORDER	9
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| #endif
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| #define LAST_PKMAP	(1 << PKMAP_ORDER)
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| #ifndef CONFIG_PPC_4K_PAGES
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| #define PKMAP_BASE	(FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1))
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| #else
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| #define PKMAP_BASE	((FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1)) & PMD_MASK)
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| #endif
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| #define LAST_PKMAP_MASK	(LAST_PKMAP-1)
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| #define PKMAP_NR(virt)  ((virt-PKMAP_BASE) >> PAGE_SHIFT)
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| #define PKMAP_ADDR(nr)  (PKMAP_BASE + ((nr) << PAGE_SHIFT))
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| 
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| #define flush_cache_kmaps()	flush_cache_all()
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| 
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| #define arch_kmap_local_set_pte(mm, vaddr, ptep, ptev)	\
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| 	__set_pte_at(mm, vaddr, ptep, ptev, 1)
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| #define arch_kmap_local_post_map(vaddr, pteval)	\
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| 	local_flush_tlb_page(NULL, vaddr)
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| #define arch_kmap_local_post_unmap(vaddr)	\
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| 	local_flush_tlb_page(NULL, vaddr)
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| 
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| #endif /* __KERNEL__ */
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| 
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| #endif /* _ASM_HIGHMEM_H */
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