71 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			71 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * xtensa mmu stuff
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|  *
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|  * Extracted from init.c
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|  */
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| #include <linux/percpu.h>
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| #include <linux/init.h>
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| #include <linux/string.h>
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| #include <linux/slab.h>
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| #include <linux/cache.h>
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| 
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| #include <asm/tlb.h>
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| #include <asm/tlbflush.h>
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| #include <asm/mmu_context.h>
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| #include <asm/page.h>
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| 
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| DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
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| 
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| void __init paging_init(void)
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| {
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| 	memset(swapper_pg_dir, 0, PAGE_SIZE);
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| }
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| 
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| /*
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|  * Flush the mmu and reset associated register to default values.
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|  */
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| void __init init_mmu(void)
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| {
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| 	/* Writing zeros to the <t>TLBCFG special registers ensure
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| 	 * that valid values exist in the register.  For existing
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| 	 * PGSZID<w> fields, zero selects the first element of the
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| 	 * page-size array.  For nonexistent PGSZID<w> fields, zero is
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| 	 * the best value to write.  Also, when changing PGSZID<w>
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| 	 * fields, the corresponding TLB must be flushed.
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| 	 */
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| 	set_itlbcfg_register(0);
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| 	set_dtlbcfg_register(0);
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| 	flush_tlb_all();
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| 
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| 	/* Set rasid register to a known value. */
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| 
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| 	set_rasid_register(ASID_USER_FIRST);
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| 
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| 	/* Set PTEVADDR special register to the start of the page
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| 	 * table, which is in kernel mappable space (ie. not
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| 	 * statically mapped).  This register's value is undefined on
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| 	 * reset.
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| 	 */
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| 	set_ptevaddr_register(PGTABLE_START);
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| }
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| 
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| struct kmem_cache *pgtable_cache __read_mostly;
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| 
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| static void pgd_ctor(void *addr)
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| {
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| 	pte_t *ptep = (pte_t *)addr;
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| 	int i;
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| 
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| 	for (i = 0; i < 1024; i++, ptep++)
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| 		pte_clear(NULL, 0, ptep);
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| 
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| }
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| 
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| void __init pgtable_cache_init(void)
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| {
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| 	pgtable_cache = kmem_cache_create("pgd",
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| 			PAGE_SIZE, PAGE_SIZE,
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| 			SLAB_HWCACHE_ALIGN,
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| 			pgd_ctor);
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| }
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